Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS FOR CONVERTING TORQUE
The present invention relates to apparatus for converting
torque and especially, but not exclusively, to apparatus for
converting a relatively small input torque into a greater output
torque.
In many applications, especially where a torque is applied
manually using a hand tool, difficulty is experienced in attempting
to provide adequate torque. One application of conveniently
converting a lower input torque to a higher output torque is to,
allow apparatus or machinery which could not previously be manually
driven by application of force in a single rotary motion, to be more
easily driven.
According to a first aspect of the present invention, there is
provided apparatus for converting torque so that a relatively small
input torque is converted to a greater output torque, the apparatus
including: an input portion adapted to receive an input torque an
input gear connected to the input portion; an output gear; and an
output portion, adapted to provide an output torque, connected to
the output gear, wherein the input gear interacts directly with the
output gear.
According to a second aspect of the present invention, there
is provided an apparatus for converting torque so that a relatively
small input torque is converted to a greater output torque, the
apparatus including: an input portion adapted to receive an input
torque; an input gear connected to the input portion; an output
gear; and an output portion, adapted to provide an output torque,
connected to the output gear, wherein the output gear is directly
connected to the output portion and unable to rotate with respect
thereto.
Preferably, the input portion is adapted to be directly
rotated by a manually operated tool. Alternatively, the input
portion may be rotated by other means, for example, a servomotor,
which may provide a predetermined torque.
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Preferably, the input portion is unable to rotate relative to
the input gear.
Preferably, the apparatus includes an interior cavity in which
the input gear is located. Preferably, the interior cavity is
defined at least partially by the output gear.
Preferably, the apparatus for converting torque includes a
plurality of input portions, which are connected to respective input
gears.
Preferably, each of the input gears interacts with the output
gear .
Preferably, the input gears) is (are) retained in position
relative to a housing portion of the apparatus.
According to a third aspect of the present invention, there is
provided apparatus for converting torque so that a relatively small
input torque is converted to a greater output torque, the apparatus
including: a first input portion adapted to receive an input torque;
a first input gear connected to the first input portion; a second
input portion adapted to receive an input torque; a second input
gear connected to the second input portion; an output gear; and an
output portion adapted to provide an output torque, connected to the
output gear, wherein a given input torque applied to the first input
portion provides a greater output torque at the output portion than
does the same torque applied to the second input portion.
Preferably, at least one of the first and second input
portions is adapted to output a torque when an input torque is input
into the other of the first and second input portions.
Preferably, the output portion is also adapted to receive an
input torque, causing an output torque at the or each input portion.
Preferably, the apparatus for converting torque further
includes a third input portion adapted to receive an input torque,
and a third input gear connected to the third input portion, wherein
a given input torque applied to the third input portion provides a
greater output torque at the output portion than does the same
torque applied to the first or second input portion.
Preferably, at least one of the input portions is adapted to
be directly rotated by a manually operated tool.
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Preferably, the input portions are unable to rotate relative
to their respective input gear.
Preferably, the input portions) and input gears) are parts
of an input gear member.
Preferably, the output gear is unable to rotate relative to
the output portion.
Preferably, the output portion and output gear are parts of an
output gear member.
Preferably, the input gears) is (are) generally cylindrical.
Preferably, the or each input gear includes a number of teeth
on an external surface thereof.
Preferably, the output gear is generally cylindrical.
Preferably, the output gear includes a number of teeth on an
internal surface thereof.
Preferably, the apparatus includes an interior cavity in which
the input , gear ( s ) i s ( are ) located .
Preferably, the interior cavity is defined at least partially
by the output gear.
Preferably, the output gear has an axis of rotation and the
output portion is located generally radially inwardly of the output
gear.
Preferably, a flange portion extends between the output gear
and the output portion.
Preferably, there is provided a direct drive input portion for
directly driving the output portion.
Preferably, the, or at least one of the input gears) drives
at least one supplementary drive gear, which acts with the input
gear to drive the output gear.
Preferably, there is provided at least one idler gear between
said input gear and said supplementary drive gear.
Preferably, said idler gear serves to provide a complementary
direction of rotation of the input gear and the supplementary drive
gear.
Preferably, the input gear is retained in position relative to
a housing portion of the apparatus.
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Preferably, the housing portion is an input end housing
portion.
Preferably, the input gear is journalled in the housing
portion.
The input gear may be journalled relative to a location
member.
The location member may be within the output gear.
Preferably, the input gears) is (are) rotatable and retained
in position relative to the housing portion of the apparatus.
Preferably, the apparatus includes at least one portion for
attachment of a bracing member for bracing at least a portion of the
torque multiplier against rotation in use.
Preferably, the apparatus includes at least one socket for
receipt of an attachment portion of a bracing member.
Preferably, the at least one socket includes a cavity' formed
in the housing portion of the apparatus.
Alternatively, the socket may be formed separately and
attached to the housing portion of the apparatus.
Preferably, the input portions are adapted to receive tools of
different sizes.
Preferably, the output portion of the apparatus may be used to
receive an input torque, causing an output torque at the or each
input portion.
Preferably, the apparatus is housed in a drum, the drum
including attachment means for attaching a base to the drum.
Features stated to be preferable above may be in relation to
the first, second and/or third aspects of the present invention.
According to a fourth aspect of the present invention, there
is provided apparatus for converting torque so that an input torque
is converted to a suitable form for driving a device which requires
reciprocal motion as an input, the apparatus including: a mounting
plate for mounting to the device; a pivot coupling; a cam mounted to
the mounting plate via the pivot coupling; and a force transmission
member which includes a cam following surface, wherein the force
transmission member is for connection to a part of the device which
requires reciprocal motion as an input; and wherein, in use, a
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torque applied to the cam causes movement of the force transmission
member suitable for providing reciprocal motion as an input to the
device.
Preferably, in use, torque is applied to the cam via the pivot
coupling.
Preferably, the cam is substantially circular.
Preferably, the cam is substantially disc-shaped.
Preferably, the cam rotates eccentrically.
Preferably, the cam following surface is generally circular.
Preferably, the apparatus includes a cover plate.
Preferably, the cover plate is, in use, located generally
parallel to the mounting plate.
Preferably, the cam and cam following surface are located, in
use, between the mounting plate and the cover plate.
Preferably, the apparatus includes supports, which extend
between the cover plate and the mounting plate.
Preferably, the apparatus further includes portions shaped
suitably for attachment to the device.
Preferably, the apparatus is adapted for use with a winch of
the type of which requires reciprocal motion of a lever in order to
operate the winch so as to pull a cable through the winch.
Preferably, the mounting plate includes mounting members
suitable for mounting an apparatus according to any of the first,
second or third aspects of the invention to the apparatus.
According to a fifth aspect of the present invention, there is
provided apparatus for mounting a device to .a plate, the apparatus
including: a plurality of brackets arranged to be spaced apart on
the plate, at least one bracket including an aperture or slot for
receipt of an elongate member therein; and an elongate member for
said bracket, wherein the elongate member is adapted to be
accommodated in the aperture or slot of the bracket and to be able
to move along its own axis through the aperture or slot of the
bracket; and wherein at least one fastening means is provided
associated with the elongate member so that adjustment of the
fastening means adjusts the axial position of the elongate member
with respect to the bracket; and wherein the elongate member is
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adapted for engagement with a complementary portion on the device to
be mounted so that when the elongate member is forced towards the
apparatus by adjustment of the respective fastening member, the
device is secured to the plate by the elongate member and the
elongate member is retained in position by the fastening member.
Preferably, a plurality of elongate members and respective
fasteners are provided.
Preferably, the one or more elongate members each include a
generally cylindrical threaded portion.
Preferably, the one or more elongate members each include a
section, which is square in cross-section, for insertion into a
complementary square cross-section socket on the device.
Preferably, the one or more fastening members are nuts.
Preferably, the one or more fastening members are wing nuts.
Preferably, rotation of the one or more fastening members
about the axis of the associated elongate member causes axial
movement of the fastening member.
Preferably, the plate is a cover plate of a torque converter
in accordance with the fourth aspect of the present invention.
Preferably, the device is an apparatus in accordance with any
one of the first, second or third aspects of the present invention.
According to a sixth aspect of the invention, there is
provided an apparatus for converting torque so that an input torque
is converted to a different output torque, the apparatus including:
an input portion adapted to receive an input torque; an input gear
connected to the input portion; an output gear; and an output
portion, adapted to provide an output torque, connected to the
output gear, wherein the input gear interacts directly with the
output gear.
According to a seventh aspect of the invention, there is
provided an apparatus for converting torque so that an input torque
is converted to a different output torque, the apparatus including:
an input portion adapted to receive an input torque; an input gear
connected to the input portion; an output gear; and an output
portion, adapted to provide an output torque, connected to the
output gear, wherein the output gear is directly connected to the
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output portion and unable to rotate with respect thereto.
According to an eighth aspect of the invention, there is
provided an apparatus for converting torque so that an input torque
is converted to a different output torque, the apparatus including a
first input portion adapted to receive an input torque, a first
input gear connected to the first input portion, a second input
portion adapted to receive an input torque, a second input gear
connected to the second input portion, an output gear, and an output
portion adapted to provide an output torque connected to the output
gear, wherein a given input torque applied to the first input
portion provides a greater output torque at the output portion than
does the same torque applied to the second input portion.
Embodiments of the invention will now be described, by way of
example only, with reference to the accompanying drawings in which:
Fig. 1 is a perspective view of an embodiment of apparatus for
converting torque in accordance with an aspect of the present
invention;
Fig. 2 is an alternative perspective view of the embodiment of
Fig. 1;
Fig. 3 is a plan view and partial cross section of the
embodiment of Figs. 1 and 2;
Fig. 4 is a side elevation of the embodiment of Figs. 1 to 3;
Fig. 5 is and alternative side elevation of the embodiment of
Figs. 1 to 4;
Fig. 6 is a cross sectional view on I-I of Fig.3;
Fig. 7 is a cross sectional view on II-II of Fig.3;
Fig. 8 is a cross sectional view on III-III of Fig.4;
Fig. 9 is a cross sectional view on IV-IV of Fig.3;
Fig. 10 is a plan view of an element, in the form of an input
end housing of the embodiment of Figs. 1 to 9;
Fig. 11 is a side view of the element of Fig. 10;
Fig. 12 is a perspective view of the element of Fig. 10~
Fig. 13 is a plan view of an element, in the form of an output
end housing of the embodiment of Figs. 1 to 9;
Fig. 14 is a side view of the element of. Fig. 13;
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Fig. 15 is a perspective view of the element of Fig. 13;
Fig. 16 is a plan view of an element, in the form of an output
gear assembly of the embodiment of Figs. 1 to 9;
Fig. 17 is a side view of the element of Fig. 13;
Fig. 18 is a perspective view of the element of Fig. 13;
Figs. 19(a), 20(a) and 21(a) are side views of three
respective input gear members of the embodiment of Figs. 1 to 9;
Figs . 19 (b) , 20 (b) and 21 (b) are respective plan views of the
members of Figs. 19(a), 20(a) and 21(a);
Figs. 19 (c) , 20 (c) and 21 (c) are respective perspective views
of the members of Figs. 19(a), 20(a) and 21(a);
Fig. 22 is a schematic side view showing the inside of an
embodiment of apparatus for converting torque in accordance with an
aspect of the present invention, connected to a winch;
Fig. 23 is a schematic side view showing the outside of the
embodiment of Fig 22 with the torque converter held in place;
Fig. 24 is a schematic cross section corresponding to XII-XII
of Fig 23;
Figs. 25 and 26 show alternative structures for an element
shown in Figs. 23 and 24;
Fig. 27 is a schematic cross section of an alternative
embodiment according to an aspect of the invention;
Fig. 28 is a plan view in partial cross section of Fig. 27;
Fig. 29 is a cross section of an apparatus of an alternative
embodiment according to an aspect of the invention;
Fig. 30 is a cross section of the apparatus of Fig. 29
illustrating a further use of the apparatus;
Fig. 31 is a cross section of the apparatus of Fig. 29
illustrating another use of the apparatus;
Fig. 32 is a cross section of the apparatus of Fig. 27
illustrating an alternative use of the apparatus;
Fig. 33 is a schematic cross section of an alternative
embodiment according to an aspect of the invention including a
vertically extending socket;
Fig. 34 is a plan view of Fig. 33;
Fig. 35 is a side view of Fig. 33;
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Fig. 36 is a schematic cross section of an alternative
embodiment according to an aspect of the invention including a
radially extending socket;
Fig. 37 is a plan view of Fig. 36;
Fig. 38 is a schematic cross section of an alternative
embodiment according to an aspect of the invention including a
single input gear member, which acts as a sun gear;
Fig. 39 is a plan view of Fig. 38;
Figs. 40a and 40b are schematic cross sections of an
alternative embodiment according to an aspect of the invention;
Figs. 41a and 41b are schematic cross sections of alternative
embodiments according to Figs. 40a and 40b, further including a
direct drive input;
Fig. 42 is a schematic cross section of an alternative
embodiment according to an aspect of the invention;
Fig. 43 is a plan view in partial cross section of Fig. 42;
Fig. 44 is a plan view in partial cross section of an
alternative embodiment of Fig. 42 and 43;
Figs. 45a and 46a are schematic cross sections of alternative
embodiments according to an aspect of the invention including a
radially extending socket;
Figs. 45b and 46b are plan views of Figs. 45a and 46a
respectively;
Fig. 47 is a plan view of an alternative embodiment according
to an aspect of the invention including three radial sockets;
Fig. 48 is a schematic cross section of an alternative
embodiment according to an aspect of the invention including a
torque input directly connected to a sun gear;
Fig. 49 is a plan view of Fig. 48;
Fig. 50 is a schematic cross section of an alternative
embodiment according to Fig. 49 including a torque input directly
driving one of the planetary drive directional correction gears;
Fig. 51 is a plan view of Fig. 50;
Fig. 52 is a schematic cross section of an alternative
embodiment according to an aspect of the invention including a
selectable friction drive mechanism;
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Fig. 53 is a plan view of an alternative embodiment according
to an aspect of the invention including a friction drive mechanism;
Fig. 54 is a schematic cross section of an alternative
embodiment according to Fig. 52 further including a direct drive
input;
Fig. 55 is a schematic cross section of an alternative
embodiment according to Fig. 52 adapted for use with wheel nuts;
Figs. 56 to 64 are plan views of alternative gear arrangements
according to embodiments of the invention;
Fig. 65 is a schematic cross section of an alternative
embodiment according to the invention including two torque
multiplication stages;
Fig 66 is a plan view of a possible gear arrangement for the
torque multiplier of Fig. 65;
Fig. 67 is a schematic cross section of an alternative
embodiment according to the invention including three torque
multiplication stages;
Fig. 68 is a schematic cross section of an alternative
embodiment according to the invention including four torque
multiplication stages;
Figs. 69a and 69b are a schematic cross section and plan view
respectively of an alternative torque multiplier including two
torque multiplication stages;
Fig 70 is a plan view of a possible gear arrangement for the
second stage of a torque multiplier;
Fig. 71 is schematic cross section of an~ alternative
embodiment according to the invention including two torque
multiplication stages and single direction friction drives;
Figs. 72a through 72e show schematic cross-sections of
alternative embodiments according to the invention in the form of a
spanner and torque multipliers for use in combination with the
spanners;
Figs. 73a, b and c show extension handles for use with
apparatus of various embodiments of aspects of the invention;
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Fig. 74 is a schematic cross section of an alternative
embodiment according to the invention in the form of a spanner
including a locking member;
Fig. 75 is perspective view of an alternative embodiment
according to the invention;
Fig. 76 is perspective cross sectional view of an alternative
embodiment according to the invention;
Fig. 77a is a semi-transparent view of an alternative
embodiment according to the invention; and
Figs. 77b to 77f show various cross-sectional views of the
embodiment of Fig. 77a.
Referring now to Figs. 1 to 9, a preferred embodiment of an
apparatus for converting torque in accordance with an aspect of the
present invention is in the form of a torque multiplier, generally
designated 1. The torque multiplier is generally cylindrical in
form, in this embodiment having a radius approximately equal to its
axial length, and includes a generally cylindrical wall 3, an input
end 5, shown uppermost in Figs. 1 and 2, and an output end 6, shown
at the bottom in Figs. 1 and 2. The input end 5 and the portion of
the generally cylindrical wall 3 which is closer to the input end 5,
are formed largely by a generally half-cylindrical input end housing
30. The output end 6 and the portion of the generally cylindrical
wall 3 which is closest to the output end 6, is formed by a
generally half-cylindrical output end housing 40.
As shown in detail in Figs. 10 to 12, and as also shown in
Figs. 1 to 9, an input end housing 30 is provided in the form of a
disc-like plate, having a thickness about half as great as its
radius. The input end housing 30 has a generally planar, radially
extending, input end surface 30A, and an axially short generally
cylindrical surface 30B which forms an input end part of the
generally cylindrical wall 3.
The input end housing 30 has first to fourth axially oriented
generally circular apertures 31 to 34, respectively, provided
therethrough. The first to third generally circular apertures 31 to
33 are angularly spaced apart and are disposed close to the
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periphery of the input end housing 30. The fourth generally
circular aperture 34, is disposed at the centre of the input end
housing 30. The input end housing 30 further includes first to
third radially extending sockets 36 to 38 respectively, each of
which has an opening in the generally cylindrical surface 30B of the
input end housing 30. The first to third radially extending sockets
36 to 38 are angularly spaced about the input end housing 30, and
are generally square in cross section.
As is best shown in Figs. 13 to 15, the output end housing 40
includes a generally circular, generally planar, radially extending,
end housing portion 40A, which has a generally circular aperture 42
provided centrally therein. The output end housing 40 further
includes an axially short generally cylindrical end housing portion
40B, which forms an output end part of the generally cylindrical
wall 3 .
The input end housing 30 and output end housing 40 are
substantially rigidly connected together by interaction of
crenulated portions 49A, 49B, 49C, which extend axially from the
generally cylindrical output end housing portion 40B, with
respective complimentary recessed portions 39A, 39B, 39C in the
generally cylindrical surface 30B of the input end housing 30 (as
shown, for example, in Fig. 12). The crenulated portions are
secured to the recessed portions 35 by suitable fasteners such as
grub screws 48A, 48B, 48C (shown in Fig. 8).
Zocated in the central fourth aperture 34 (Fig. 12) of the
input end housing 30 is an axially extending direct drive input
portion 14, which is able to rotate relative to the input end
housing 30 and output end housing 40. The direct drive input
portion 14 (Fig. 1) includes a square drive cavity 14A, for receipt
of a driving portion of a driving tool. such as a square drive
ratchet wrench, suitable lever, or the like. The direct drive input
portion 14 forms part of an output gear member 24 of the torque
multiplier (Figs. 16 to 18) which further includes an axially
extending central shaft 17 which extends the axial length of the
torque multiplier 1 and terminates at the output end in an output
portion 16. In use, the output portion 16 extends out of the
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circular end housing portion 40A, through the central circular
aperture 42 (Fig 13), and, in this embodiment, terminates in a drive
portion, which is square in radial cross section so that it can
conveniently be used to drive tools with a suitable square-drive
connection. Because the direct drive input portion 14 and the
output portion 16 are directly and rigidly connected, it will be
appreciated that rotation of the direct drive,input portion 14 by a
given angular displacement will result in the same angular
displacement of the output portion 16.
Referring to Figures 1 to 9 once more, from a portion of the
central shaft 17 which is, in use, immediately inside the circular
output end housing portion 40A, a flange 18 extends radially
outwardly, substantially to the inside of the cylindrical end
housing portion 40B of the generally cylindrical wall 3. Extending
axially, and, in use, towards the input end 5 of the torque
multiplier 1, from the generally circular periphery of the flange
18, is a cylindrical output gear 19, which has a plurality of output
gear teeth 26 on a radially inner surface thereof. It will be
appreciated that in this embodiment the radius of the output gear 19
is only slightly smaller than the radius of the torque multiplier 1,
and the axial length of the output gear 19 is only slightly smaller
than the axial distance between the flange 18 and the input end
housing 30. As seen in Figs. 16 to 18, the flange 18, output gear
19 and gear teeth 26 are parts of the output gear member 24.
First to third input gears, 21 to 23 respectively, are
provided for interaction with the output gear 19. Each of the input
gears 21 to 23, has a plurality of input gear teeth 25, which
interlock, and drive (or could, if an input torque were applied to
the output portion 16, be driven by) the output gear teeth 26.
As is best shown in Figs. 19 (a) to 21 (c) , the input gears 21
to 23, are formed as parts of respective first to third input gear
members 27, 28, 29 and are thus rigidly connected to and in this
embodiment formed integrally with, respective generally cylindrical
first, second and third torque input portions, 11, 12, 13. In use,
the first, second and third torque input portions, 11, 12, 13 extend
axially through the respective first, second and third apertures 31,
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32, 33 (Fig 10) of the input end housing 30. The first, second and
third torque input portions, 11, 12, 13 each include a respective
square drive cavity 11A, 12A, 13A, for receipt of a driving portion
of a driving tool such as a square drive ratchet wrench, suitable
lever, or the like. Each input gear member 27, 28, 29 is retained
against radial movement relative to the input end housing 30 by
being journalled in the respective aperture 31, 32, 33 of the input
end housing 30 and is retained against axial movement by engagement
of respective radially extending external shoulders 11B, 12B, 13B,
of the input gear members 27, 28, 29 with respective internal
shoulders 31B, 32B, 33B of 30 the apertures 31, 32, 33 through which
they extend.
Each input gear member 27, 28, 29 is further rotatably
retained relative to the other input gear members, and against
significant radial movement relative to the output gear 19 and the
central shaft 17, by location of a respective axially extreme,
output end, circular lug (not shown) which is, in use, located in a
respective aperture, e.g. of a location plate 20 (Fig 9). The
location plate 20 is located between the input gears 21, 22, 23 and
the flange 18, and can rotate relative to the output gear member 24.
The location plate 20 thus includes a number of apertures,
namely one to journal an end lug of each of the (in this embodiment
three) input gears 21, 22, 23 and one to allow the central shaft 17
to pass therethrough. In the embodiment of Figs. 1 to 9, the
location plate 20 is optional, since the input gear members are
securely journalled in the axially thick input end housing 30. In
alternative embodiments, and/or where there are gear members, which
are not securely journalled in the housing, a location plate (or
other location member) may be of greater necessity.
As is best illustrated in Figs. 8 and 19 to 21, each of the
input gears 21, 22, 23 has a different number of input gear teeth
25, and in each case the number is considerably less than the number
of output gear teeth 26, so that a mechanical advantage, or torque
multiplication, proportional to the ratio of the number of teeth
will be provided (although some loss due to friction occurs) upon
rotation of the input portions 11, 12, 13. Using the embodiment of
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Figs. 1 to 9 a user may therefore select direct drive (torque
multiplication of unity) or a multiplication of three, four or six
(excluding frictional losses) by applying torque to the direct drive
'14, or the first second or third torque input portions 11, 12, 13
respectively. As can be seen in the embodiment of Figs. 1 to 9, the
first, second and third input gears 21, 22, 23 have twelve, eight
and six teeth respectively, and the output gear 19 has 36 teeth. It
will be appreciated that the input and output portions of the
apparatus of Figs. 1 to 21 may be used in the opposite role, that is
the apparatus may be driven from the output portion to the input
portion, in a case where the apparatus is to be used as a speed tool
rather than a torque multiplier. The apparatus may also be driven
from one of the inputs to another one of the other inputs.
It will be appreciated that, when using the torque multiplier
1 (other than on direct drive) the apparatus itself must be braced
against rotation. This bracing may be provided by connection of a
suitable bracing member (not shown) to one of the sockets 36, 37,
38. Provision of suitable connections, and most preferably sockets,
for attachment of one or more bracing members may be preferable to
forming the apparatus with a bracing bar integrally or permanently
connected, since a more compact and flexible apparatus results. In
one embodiment (described below) a torque multiplier is conveniently
attachable to other apparatus by use of such connections, in a way
which would not be practicable using a permanently attached bracing
bar .
Referring now to Figs. 22 to 26, a preferred embodiment of an
apparatus for converting torque in accordance with an aspect of the
present invention is in the form of a torque converter, generally
designated 50, for converting an input torque into a suitable form
for driving apparatus which requires reciprocal motion as an input.
A preferred application of the torque converter 50 is to drive an
apparatus often known as a TIRFORTM, GRIPHOISTTM or GREIFZUGTM machine.
Such machines, schematically indicated in Fig. 22 and generally
designated 60, are a type of winch or hoist which uses reciprocating
motion (indicated by the arrow in Fig. 22) of a manually operated
lever 61 to effectively pull a wire rope 62 through the TIRFORT"
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machine 60 (or, alternatively, to pull the TIRFORTM machine 60 along
a wire rope 62). Although extremely useful, TIRFORTM machines are
strenuous to use, since in order to operate under large loads a
considerable force must be applied to move the lever 61, often in an
inconvenient position.
Fig. 22 illustrates schematically, a preferred embodiment of
an apparatus, which allows application of a torque, that is a rotary
motion, to be used to drive a machine such as a TIRFORTM machine 60.
The apparatus includes a mounting plate 51, which is securely
attached to the machine 60. Mounted to the mounting plate 51 is, a
cam 52, which in this embodiment is substantially circular and
mounted eccentrically about a pivot coupling 53. The pivot coupling
53 includes a connection portion (not shown), such as, for example,
a square drive socket, and is rigidly connected to the cam 52, so
that rotation of the pivot coupling 53 causes the cam 52 to rotate
eccentrically. Surrounding the cam 52 is a first end, in the form
of a ring fitting 54, of a force transmission member 55. The ring
fitting 54 includes, at the radially inner part thereof, a
substantially circular cam following surface 56 for engagement with
the cam 52.
The force transmission member 55 has a second end 57, which,
in use, is pivotally attached to the lever 61 of the TIRFORTM machine
60. The force transmission member 55 also includes an intermediate
portion 58, between the first and second ends thereof, and where the
intermediate portion 58 connects to the ring fitting 54, the
intermediate portion 58 includes somewhat concave portions 58A to
allow compact design while helping to avoid undesirable interaction
or collision of the intermediate portion 58 with any edge of the
apparatus.
It will be appreciated that rotation of the pivot coupling 53
causes the cam 52 to rotate eccentrically and that this in turn
drives the cam following surface 56, causing the force transmission
member 55 to effect reciprocal motion of the lever 61.
For large loads it may not be practicable to apply adequate
torque manually to the pivot coupling 53 without some form of
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gearing or torque multiplication, and the torque multiplier of Figs
1 to 9 is well suited to such a use.
In a preferred embodiment a torque multiplier of the general
type illustrated in Figs 1 to 9 is securely (albeit indirectly)
connected to the mounting plate 51, and such an arrangement is
illustrated schematically in Fig. 23.
Fig. 23 shows schematically a torque multiplier of the general
type illustrated in Figs 1 to 9, secured to a cover plate 70. The
cover plate 70 is, in use, secured to the mounting plate 51 by any
suitable means, and a preferred arrangement is shown schematically
in Fig. 24, and will be described below. The torque multiplier 1 is
secured to the cover plate 70 by first, second and third securing
members 7l, 72, 73, respectively. Each securing member 71, 72, 73
is elongate in form and includes a threaded shaft portion (72A, 73A
in Fig. 24) which extends from a first end of th'e securing member
approximately two thirds along the securing member, and which, in
use, is distal from the torque multiplier 1. Each securing member
71, 72, 73 also includes a square cross section portion (72B, 73B in
Fig. 24) constituting approximately the remaining third of its
length, for engagement in a respective socket 36, 37~, 38 of the
torque multiplier. Alternatively or additionally, a circular cross-
section portion may be provided.
In use, each securing member 71, 72, 73 is secured to the
cover plate 70, by retention in a respective bracket, 74, 75, 76.
The brackets 74, 75, 76 are preferably small plates upstanding from
the cover plate 70, each including an aperture through which the
respective securing member extends. The apertures may be circular
apertures, as illustrated in Fig. 25, or may be open slots 75A in
order to facilitate insertion of the securing members, as
illustrated in Fig. 26. The axial position of each securing member
71, 72, 73 is adjustable by operation of one or more associated nuts
78, which may be wing nuts, and which cooperate with the threaded
portions of the securing members 71, 72, 73 and which may bear
against the respective bracket 74, 75, 76 in order to position the
securing means 71, 72, 73.
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It will be appreciated that rotation of one of the nuts 78
causes axial movement of the nut 78 relative to the securing member
to which the nut 78 is attached. If the torque multiplier is
located so that its output 16 is connected to the connection portion
of the pivot coupling 53, the securing member 71, 72, 73 is inserted
in a socket of the torque multiplier and also in the~aperture or
slot of an associated bracket 74, 75, 76, then a given nut 78 can be
rotated so that it abuts its respective bracket 74, 75, 76, at which
its axial movement is stopped by the bracket 74, 75, 76. The
securing member is then effectively held in compression between the
bracket/nut and the torque multiplier. Providing securing members
on opposing sides of (or suitably spaced around) the torque
multiplier results in convenient and secure location of the torque
multiplier. When the nuts 78 are moved away from their brackets 74,
75, 76, the securing members can be moved axially, and thus easily
removed from the torque multiplier.
Tt should also be appreciated that in an alternative
embodiment, the torque multiplier could be secured by being abutted
against a suitably shaped fixed bracket on the plate and forced
toward the bracket by an elongate member. Thus, only one elongate
member and one socket on the torque multiplier might be necessary.
Referring now to Fig 24, the structure of the apparatus 50
will now be described. The apparatus 50 includes first and second
side supports 81, 82 which, in use, extend along the sides of the
TIRFORTM machine 60 and support the mounting plate 51 and the cover
plate 70. The side supports 80, 81 are spaced apart so that a given
TIRFORTM machine may fit therebetween. TIRFORTM machines typically
have small flanges 64 running along their edges, and the side
supports 80, 81 include, at their extremes, respective shoulders 82,
83 for engagement with the flanges 64. The shoulders 82, 83 are
secured to the flanges by suitable fasteners 85, 86, shown
schematically in Fig. 24, such as bolts, and, as seen in Fig. 24,
corresponding apertures are provided in the shoulders 83, 84 and in
the flanges 64. In the preferred embodiment access apertures (not
shown) are provided in the side supports 81, 82 in order to allow
access to fasteners, such as nuts, which may be located, in use,
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between the flanges 64 and the mounting plate 51. This type of
fastening is economical, secure, reversible, and requires minimal
modification of the TIRFORT" machine, although, of course,
alternative means of securing the apparatus 50 to the TIRFORTM
machine 60 including welding, clamping or the like may be suitable
alternatives depending on the circumstances.
The mounting plate 51, extends between the side supports 81,
82 and effectively supports the cam 52 and separates the cam 52 from
the TIRFORTM machine 60. The pivot coupling 53 is journalled in the
mounting plate 51. The side supports 81, 82 provide respective
upstanding rim portions 91, 92 and respective inwardly extending
ledge portions 93, 94 to support and locate the cover plate 70. The
upstanding rim portions 91, 92 extend in the direction of the
thickness of the cover plate 70 and are dimensioned so that the
cover plate 70 may sit flush between them. The ledge portions are
dimensioned so that appropriate fasteners (such as bolts -not shown)
may extend through the ledge portions 93, 94 and the cover plate 70
in order to secure the cover plate 70. The ledge portions 93, 94
are provided with means to allow such fastening, such as threaded
apertures, captive nuts, or the like.
Referring back to Figs 22 and 23, in order to increase the
stroke applied to the lever 61, the connection between the second
end of the force transmission member 55 and the lever 61 may include
a cam attached to the lever 61 and a cam follower forming the second
end of the force transmission member 55. The transmission member 55
may be connected to the lever 61 at a selected axial position on the
lever 61 to provide a selected mechanical advantage.
It will be appreciated that the torque converter 50,
especially in combination with the torque multiplier 1, provides a
convenient and useful means of converting a machine such as a
TIRFORTM machine from a machine which is labour intensive and
possibly cumbersome to operate using a reciprocal action, into one
which is much easier and more convenient to operate using a rotary
action. If desired, a powered driving device, for example, a power
tool such as an electric drill, might be suitable for applying the
required torque to the input of the torque multiplier 1.
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Fig. 27 and subsequent figures show embodiments of torque
multipliers in accordance with one or more aspects of the present
invention that are variations or alternative embodiments to the
embodiment illustrated in Figs. 1 to 9. Similarities with the
embodiment of Figs. 1. to 9 will be apparent to those skilled in the
art and will not be discussed in detail.
Fig. 27 is a cross-section of a torque~multiplier generally
designated 101 with a housing 130 in the form of a casing, rather
than including an input end housing as great in axial extent as the
input end housing 30 of the torque multiplier 1 of Figs. 1 to 9. An
input end 130A of the housing 130 includes one or more apertures 131
to allow respective input gear members 127 to extend from respective
torque input portions 111 thereof through the input end housing 130A
so that respective input gears 121 can interact with an output gear
119. The torque converter 101 includes a central output cylinder
117, which may be regarded as analogous to the central shaft 17 of
the embodiment of Figs 1 to 9, but which is generally cylindrical in
shape so that a continuous bore 135 extends through the centre of
the torque multiplier 101. This enables the torque multiplier 101
to be used to operate fasteners such as bolts on long threaded
shafts, such as those found in some designs of heat exchanger. In
use, the torque multiplier 101 may effectively travel along the
shaft with the fastener, with the shaft extending through the bore
135. In the illustrated embodiment, the cylinder 117 includes an
input end at which the central bore is square in cross-section to
allow it to be driven by a square drive tool, and an output end at
which the bore 135 is hexagonal in cross-section in order to allow
engagement with a fastener such as a nut, or an adaptor for
connection to such a fastener.
The torque multiplier 101 further includes a location member
120 in which input gear members 127 are journalled and, in this
embodiment, the location member 120 includes an output end location
plate 120A which includes apertures in which end lugs of the input
gear members 127 are journalled and an input end plate 120B which
includes portions which may bear against and assist in the location
of a part of the input gear member 127 intermediate a torque input
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portion 111 and the input gear 121 of each respective input gear
member 127. In the embodiment of Fig. 27, it will be appreciated
that the input end portion 130A of the casing 130 is not
sufficiently axially thick to include socket apertures therein.
Sockets 137 are thus provided as generally cylindrical members
having radially outwardly open bores which are square in cross-
section provided therein although they could be of circular cross-
section. The sockets 137 are attached to the input end housing 130A
by welding, or may be formed integrally therewith.
Fig. 28 is a plan view in partial cross-section of the
embodiment of Fig. 27 in which first, second and third sockets 136,
137, 138 are shown, and in which location of first to third input
gears 121, 122, 123, each providing a different number of teeth for
interaction with the output gear 119, can be seen. The torque
multiplier 101 includes first and second supplementary input drive
gears 171, 172 which are driven by the first input gear 121 via
first and second idler gears 181, 182. The supplementary input
gears 171, 172 engage the output gear 119 and thus help to
distribute the force applied to the output gear 119 when the first
input gear 121 is driven. The idler gears 181, 182 do not engage
the output gear 119, but ensure that the input gear 121 and
supplementary input gears 171, 172 rotate in the same direction in
use. The idler gears 181, 182, also allow the distribution of
torque received by the first input gear 121 to be shared across the
two supplementary input gears 171, 172 where a high input torque is
provided, and/or a low number of teeth are provided on the gears.
The supplementary input gears 171, 172 and idler gears 181, 182 are
journalled in the location member 120, and do not extend outside the
casing 130. The second and third input gears 122, 123 drive the
output gear 119 only, and do not have associated idler and
supplementary drive gears.
It would be appreciated that, in use, the casing 130 is braced
against rotation by one or more bracing members located in one or
more of the sockets 136, 137, 138, and that the housing 130, input
gears 121, 122, 123, location member 120, idler gears 181, 182 and
supplementary input gears 171, 172 do not rotate about the axis of
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the torque multiplier 101 in use. The output cylinder 117 and
output gear 119 (which may be formed as a single element
constituting an output member) do rotate in normal use of the torque
multiplier.
Fig. 29 illustrates use of a torque multiplier 102 that is
similar to the torque multiplier 101 in operating a nut 192 on°a
threaded shaft 192. The torque multiplier of Fig. 29 can be
specifically designed to drive any size of nut allowing the threaded
shaft 192 to pass through the tool. This tool can travel down the
threaded shaft 192, as the nut 191 is moved down the shaft 192,
which makes it particularly suitable for use with heat exchanger
head plates, as discussed above.
t
Fig. 30 illustrates use of a torque multiplier 103 similar to
the torque multipliers 101, 102 in which a socket adaptor 150 is
used to drive a large nut 160 on a threaded shaft 161. The socket
adaptor 150 includes a driven portion 152, which is generally
cylindrical but which has an outer surface which is hexagonal in
cross section for engagement with the output of the torque
multiplier 103, and which is relatively radially small in extent and
which has a bore therethough for passage of the threaded shaft 161.
The socket adaptor 150 further includes a driving portion 154, which
has an internal surface 156 which defines a cavity which is
hexagonal in cross-section in order to accommodate the nut 160. The
driven portion 152 and driving portion 154 are connected by a
radially extending flange portion 153.
Fig. 31 shows the torque multiplier 103, in use, with a drive
adaptor 162. The drive adaptor is provided in order to provide a
square drive output for the torque multiplier 103. The driver
adaptor 162 is an elongate member, which is locatable in the drive
cylinder of the torque adaptor 103. The drive adaptor 162 includes
a driven portion which is hexagonal in cross-section and dimensioned
to co-operate with and to be driven by the drive cylinder of the
torque adaptor 103, and further includes a first square drive output
164, which is square in cross-section and which provides a 11~ inch
(approximately 32mm) drive at one end thereof and a second square
drive output 165, which provides a 1'~ inch (approximately 38mm)
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drive. The adaptor 162 is provided with ball detents for secure
connection to the torque multiplier 103 and to sockets or other
members that are to be driven. Also shown in Fig. 31 is an
alternative drive adaptor 166 which includes a central driven
portion, an end portion which provides a 1 inch (approximately 25mm)
drive 168 and a 3~ inch (approximately 19 mm) drive 169.
Although various cross-sectional shapes are referred to
herein, it will be appreciated that these are provided for
illustration only and many variations and alternatives will be
apparent to the skilled person.
Fig. 32 shows schematically an alternative in which the torque
multiplier 101 of Fig. 27 may be used to operate sockets via square
cross-section drive blocks 198, which may be driven by what is
nominally the drive or input portion of the output cylinder 117. It
will be appreciated that an output socket, for example socket 199 in
Fig. 32 can be driven on what is nominally the input side of the
torque converter 101. This may be useful where space is restricted.
The position of the socket 199 will, in use, tend to prevent a tool
inserted into the torque input portion 111 from being rotated by
360° but effective operation can be achieved by use of a ratchet
wrench or similar device through a limited angular range, with the
ratchet or similar mechanism enabling the wrench to be returned to
its original position without rotation of the torque input portion
111.
It will be appreciated that torque multipliers as described
above may be of great convenience in operating nuts on long rods in
devices such as heat exchangers where some previous devices have
been very expensive and cumbersome.
Figs. 33 to 35 show an alternative embodiment of a torque
multiplier in accordance with one or more aspects of the present
invention. The torque multiplier, generally designated 201,
includes a first torque input portion 211 which is geared to provide
a torque multiplication of approximately 3:1 and a direct drive
input portion 214. This embodiment of a torque multiplier 201
therefore differs from the previously illustrated embodiments by
having one direct drive and only one geared, torque input. This
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embodiment of a torque multiplier 201 further differs from some of
the other described embodiments in that an outer cylindrical wall of
an output gear member 224 provides the outer cylindrical wall of the
torque multiplier 201 and a flange 218 which forms part of the
output gear member 224 forms the output end of the housing. A
generally circular plate forms the input end housing 230 (Fig. 35)
and the input end housing 230 is retained in position relative to
the output gear member 224, but able to rotate relative thereto, by
a retention member 240. The retention member 240 has a first
portion 240A, which extends from a central part of the input end
housing to a periphery of the torque multiplier 201, a second
portion 240B, which extends axially along the outside of the
cylindrical portiow of the output gear member 224, a third portion
240C, which extends diametrically across the flange 218 of the
output gear member 224 and a fourth portion 240D, which extends
axially from the output end of the torque multiplier to the input
end of the torque multiplier along the cylindrical part of the
output gear member 224, where it is attached to a socket 236. Thus,
in use, the socket 236, input end housing 230, and retention member
240 do not rotate about the axis of the torque multiplier 201, but
the output gear member 224 including the flange 218 and an output
portion 216 do rotate about the axis of the torque multiplier 201.
Using the outer surface of the output gear member 224 as part of the
housing of the torque multiplier 201 may be useful to minimise the
weight of the device. It will be appreciated that the torque
multiplier is reversible and could be driven from the output portion
216 which would result in a 1:3 ratio to the output at the first
input portion 211.
Figs. 36 and 37 show an embodiment in which a socket 237 is
provided extending radially from an external wall, formed by
retention member 241. Such a configuration may be useful in some
circumstances but is generally not preferred since it increases the
radial size of the torque multiplier. It will be appreciated that
the retention member 241 in Figs. 36 and 37 is generally analogous
to the retention member 240 in Figs . 33 to 35, but is of slightly
different configuration, while still extending a significant way
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around the outside of the torque multiplier and rigidly fixing the
socket 237 to an input end housing 230A and rotatably retaining both
to the output gear member 224A. The embodiment of Figs. 36 and 37
has a single torque input 212, which will be understood by analogy
with other embodiments described herein. It will be appreciated
that the torque multiplier is reversible and could be driven from
the output portion 216, to the torque input 212, which would result
in a reversed ratio to that supplied by driving the single torque
input 212.
Figs. 38 and 39 shows schematically an embodiment having a
single input gear member 213 which acts as a sun gear and which
drives an output gear 244 via first and second planetary idler gears
251, 252 each of which drives respective first and second planetary
drive gears 253 to 256. In the preferred embodiment, the sun gear
has a diameter of approximately 400 of the diameter of the output
gear 244 giving a torque multiplication of approximately 2.5. For
example, in order to achieve an output ratio of 1:2.5, the sun gear
213 would be approximately 20mm in diameter, the planetary gears
idler and drive gears 251, 252, 253, 254, 255, 256 would be
approximately l5mm in diameter, and the output gear 244 would be
approximately 47.7mm in diameter
It will be appreciated that the torque multiplier is
reversible and could be driven from the output portion 216 which
would result in a reversed ratio to that supplied by driving the
single torque input 213.
Fig. 40a shows schematically a torque multiplier in which a
single off centre input gear member 261 engages an output gear 262
to give a torque multiplication of approximately 4. An external
toothed ring gear 263 is included concentric to and radially inside
the output gear 262. The ring gear 263 enables the input gear
member to drive a supplementary drive gear 264 which also drives the
output gear 262 and thereby helps to distribute the input force.
One or more generally annular location plates 265, 266, 267 are
provided in order to locate the gears relative to each other.
Again, the torque multiplier is reversible and could be driven from
the output portion 216, the input portion then providing the output
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from the converter, which would result in a reversed ratio to that
supplied by driving the single torque input 261.
Fig. 40b illustrates an embodiment similar to that of Fig. 40a
but includes a direct drive input 268 functioning in the same manner
described above with respect, for example, to Figs. 1 to 9.
Fig. 41a and 41b correspond to Figs. 40a and 40b respectively,
with the exception that casing 262 fully encloses the mechanism
within the apparatus, and the socket 237B is positioned
diametrically opposite the input gear member 261.
Figs. 42 and 43 illustrate a further embodiment of a torque
multiplier which will be understood with reference to the
description of the embodiment of Figs. 27 and 28, although it will
be appreciated that the embodiment of Figs. 42 and 43 has a central
shaft 117b, which can be engaged from each axial side of the
apparatus, rather than a drive cylinder (117 in Fig. 27). The
torque multiplier is reversible and could be driven from the output
portion 117b, which would result in a reversed ratio to that
supplied by driving the torque input in Fig 42. Additionally, no
second or third peripheral inputs are provided.
Fig. 44 illustrates a variation of the embodiment of Figs. 42
and 43 in that only a single socket 238 is provided.
Figs. 45a and 45b illustrate a further variation in which a
socket 238A is provided extending radially from a cylindrical side
of the torque multiplier.
Figs 46a and 46b correspond to the embodiment shown in Figs
45a and 45b respectively, with the exception that casing 2600
extends entirely around output gear 119, and socket 2620 is placed
diametrically opposite input 121.
Fig. 47 shows a further variation with three peripheral torque
inputs 121, 122, 123 in addition to a central input 2628 and three
sockets 2622, 2624, 2626 for bracing members, which are
diametrically opposite the three peripheral inputs 121, 122, 123.
All three peripheral inputs 121, 122, 123 drive the internally
toothed output gear 119.
Figs. 48 and 49 illustrate a torque multiplier having a single
torque input portion 402 directly connected to a sun gear 401. The
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sun gear 401 drives first, second and third idler gears 403, 404,
405 each of which drives two of a total of six planetary drive gears
406 to 411. The planetary drive gears in turn drive an output gear
412, which, analogous to output gears in other embodiments, is
rigidly connected to an output 416. In the illustrated embodiment,
the ratio of teeth on the sun gear to the output gear is about
5.5:1, providing a corresponding torque multiplication. For
example, the sun gear 401 is 18mm in diameter and has 12 gear teeth,
first, second and third idler gears 403, 404, 405 have 24 teeth and
the six planetary drive gears 406 to 411 have 12 teeth, while the
output gear 412 has approximately 66 gear teeth.
The sun gear 401, idler gears 403, 404, 405 and planetary
drive gears 406 to 411 are retained in appropriate positions by
first and second location plates 413, 414. The purpose of the idler
gears 403, 404, 405 is to correct rotation to ,correspond with the
input rotation direction. Additionally, by having multiple idler
gears 403, 404, 405, engaged with the input gear 401, and multiple
planetary gears 406 to 411 engaged with each idler gear 403, 404,
405, the input force is distributed through multiple gears. The
input portion 402 is provided with an 0-ring seal 415 in order to
avoid entry of debris or fluid from the input side to the interior
of the torque multiplier. The input portion 402 is further provided
with a square drive cavity 417, which extends in the axial direction
of the torque multiplier, and also with a radial through-bore 418,
in this embodiment in the form of a circular 13mm aperture. The
through-bore 418 allows the torque input portion to be driven by
insertion of any appropriate lever or bar making the torque
multiplier more flexible in operation than it would be if it were
dependent upon provision of a square drive tool.
The apparent asymmetry in the sun gear 401 is intended to
illustrate only the meshing of the teeth of the sun gear 401 with
the teeth of the idler gear 404, and is not intended to indicate
asymmetry in the gear.
Figs. 50 and 51 show a variation of the embodiment of Figs. 48
and 49 in which a torque input 419 is provided to directly drive one
of the planetary drive gears. In the illustrated embodiment, it
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will be appreciated that the planetary drive gears and the sun gear
are of the same diameter, and have the same number of teeth, but
embodiments and variations in which a choice of torque
multiplications is available may be easily provided by providing a
driven sun gear and a driven planetary drive gear with different
sizes and different numbers of teeth. This will result in the
torque multiplier having two different torque outputs.
Fig. 52 illustrates an embodiment of a torque multiplier in
which a friction drive mechanism 420 is provided as part of the
torque input portion 421.
As shown in Fig. 53, the mechanism is of the type described in
US Patent No. 3621739, the contents of which are hereby incorporated
by reference. It will be appreciated that other drive mechanisms
could be used as alternatives, including conventional ratchet
wrenches or other friction drive heads. The embodiment of Fig. 52
(and indeed other embodiments) could be oil filled in order to
reduce friction via oil refill plug 4200, although in order to avoid
unnecessary weight and risk of leakage, a lubricating grease is
preferred.
Fig. 54 illustrates a variation of the embodiment of Fig. 52
and includes a direct drive input 422. The direct drive input is a
1:1 ratio and the torque input portion 421 is a suitably higher
ratio depending on the arrangement of the torque multiplier.
Fig. 55 illustrates a variation of the embodiment of Fig. 34,
which is a dedicated unit for operating wheel nuts and includes a
direct drive input 4280, a torque drive input 4290, oil refill plug
4220 and an output 423 which includes a cavity 424 which is
hexagonal in radial cross-section so that it can be directly fitted
onto a wheel nut 425. The wheel nut 425 could be of any type and is
shown attached to a wheel hub 4240 and a wheel rim 4250 for
completeness. Also shown is an extension bar 4230, which can be
fitted to the output 423 in the case where there is a confined space
in which to remove the nut 425. The torque drive input 4290
includes a hole 4270 which is adapted to receive a bar or rotating
tool [not shown] in order to turn the torque input drive 4290. The
torque drive input 4290 is hexagonal in cross-section, so that it
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can also be driven by a wheel brace or socket (not shown.). The
torque drive input 4290 further includes an 0-ring seal 4260 in
order to avoid entry of debris or fluid from the input side to the
interior of the torque multiplier.
In operation, if a nut from a vehicle wheel is required to be
removed, the torque multiplier is applied by placing the wheel nut
425 into cavity 423 or alternatively through the cavity of the
extension bar 4230 (then the torque multiplier is applied to the
extension bar). The torque drive input 4290 is then turned,
preferably by using a wheel brace or bar [not shown] through hole
4270 in order to loosen the nut 425. Once the nut 425 has been
loosened, the direct drive 4280 may then be used to remove the nut
425 from the wheel hub 4240 more quickly than would occur for the
same number of turns of the torque input drive 4290. It will be
appreciated that the output 423 may be of various different sizes
and/or different sized engaging portions or extensions, fitted to
the output 423 can be used.
Figs. 56 to 64 show arrangements of driven gears and idler
gears, which could be used in alternative embodiments of torque
converters. Each of the embodiments in Figs. 56 to 64 includes a
sun gear, generally designated 500. The sun gear can conveniently
be used to transmit motion from a cylindrical gear at one part of
the torque multiplier interior to a cylindrical gear at another part
of the torque multiplier interior, while minimising the number of
intermediate gears, and allowing a direct drive or central shaft to
pass through the interior of the sun gear. This allows effective
transmission of force in order to distribute the load and avoid or
reduce wear and/or damage to the gears while conveniently allowing a
central direct drive. The number of~idler gears and supplementary
drive gears may be selected to provide appropriate load distribution
for the purpose of the tool and the materials from which it is made.
Figs. 56a and 56b illustrate an exemplary gear arrangement for
a dual drive torque multiplier in order to provide equal load
distribution for both forward and reverse direction of the drives.
The dimensions of the gears may be of any suitable size in order to
provide the desired torque multiplication.
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As shown in Fig. 56a, the gear arrangement for the torque
multiplier includes an internally toothed ring gear 5090 (106mm
diameter) and an externally toothed sun gear 500 (54mm diameter)
concentric with ring gear 5090. Sun gear 500 is concentric with,
and free to rotate around, a direct drive input 5010, which is
integral with an output portion 5500, thereby providing a torque
multiplication of 1:1. The ring gear 5090 is also integral with the
output portion 5500. As best seen in Fig. 56b, the gear arrangement
further includes an externally toothed drive (input) gear 5040 and
two supplementary drive gears 5030, 5050 (all 20mm in diameter), the
teeth of which engage with the teeth of the ring gear 5090. Drive
gear 5040 is connected to a torque input 5020 having a torque
multiplication of 5:1 to the output portion. The gear arrangement
further includes first and second intermediate planetary gears 5100,
5110 (each 20mm diameter) connected between the drive gears 5030,
5040 and 5050 and sun gear 500. First intermediate planetary gear
5100 is connected between drive gears 5030, 5040 and sun gear 500
while second intermediate planetary gear 5110 is connected between
drive gears 5040, 5050 and sun gear 500. When the input drive gear
5040 is driven, it drives both the planetary gears 5100, 5110, which
drive the sun gear 500. By driving the sun gear 500, the force from
the input gear 5040 is spread to both the planetary gears 5100, 5110
equally, and to both supplementary drive gears 5030, 5050. Each of
the supplementary drive gears 5030, 5050 also drives the ring gear
5090, hence the output portion. Due to the symmetry of the
supplementary and planetary gears on either side of the drive gear
5040, equal distribution is obtained in both directions of rotation
of the drive gear 5040. The planetary gears 5100, 5110 also provide
directional correction so that input and output torques are in the
same direction.
Fig. 57 illustrates an exemplary gear arrangement for a
dual drive torque multiplier in order to proportion the drive load
in both the forward and reverse directions. The dimensions of the
gears may be of any suitable size in order to provide the desired
torque multiplication.
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The gear arrangement for the torque multiplier includes the
set up of internal gears described with reference to Figure 56
above, with the addition of a further planetary gear 5120, which is
engaged with the sun gear 500 and two associated supplementary drive
gears 5060, 5070, which are of equal size and are engaged between
the ring gear 5090 and further planetary gear 5120. The further
planetary gear 5120 is provided axially opposite the drive gear
5040, and is driven .via the sun gear 500 via its associated
supplementary gears 5060, 5070. The ring gear 5090 is also driven.
This further serves to distribute the input force received at the
drive gear 5040 around the ring gear 5090 with the four
supplementary drive gears. Once again, the symmetrical arrangement
of the gear in a plane through the axes of rotation of the input
drive gear 5040 and direct drive input 5010 allows equal loading in
both rotational directions.
Fig. 58 illustrates an exemplary gear arrangement for a dual
drive torque multiplier in order to proportion the drive load in
both the forward and reverse directions. The dimensions of the
gears may be of any suitable size in order to provide the desired
torque multiplication. The gear arrangement includes the gear
arrangement described with reference to Fig. 56 above; the elements
of Fig. 57 shared with Fig 56 are also shared with this arrangement.
However, in this arrangement, a single further supplementary drive
gear 5060 is provided axially opposite the drive gear 5040. The
further supplementary drive gear 5060 drives the ring gear 5090 and
is driven by the sun gear 500 via two equally sized planetary gears
5120, 5130 mounted between the further supplementary drive gear 5060
and the sun gear 500.
Fig. 59 illustrates an exemplary gear arrangement for a dual
drive torque multiplier in order to provide equal load distribution.
The dimensions of the gears may be of any suitable size in order to
provide the desired torque multiplication.
This arrangement includes a central sun gear 500, and a
concentric, internally toothed, ring gear 5090. Three planetary
gears 5100, 5101, 5102 are positioned, engaged with the sun gear
500, at equal separations around the sun gear 500. Each planetary
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gear 5100, 5101, 5102 is engaged with the ring gear 5090 via a pair
of drive gears. One of the drive gears 5040 is a primary drive
gear, which receives drive input, while the others are supplementary
drive gears. The primary drive gear 5040 drives the ring gear 5090
and also the engaged idler gear 5100. That idler gear 5100 drives
the first supplementary drive gear 5030 (which drives the ring gear
5090) and also drives the sun gear 500. The sun gear 500 drives the
other idler gears 5101, 5102, which in turn drive the further
supplementary drive gears 5050 to 5080, and thus the ring gear 5090.
Figs. 60, 61 and 62 illustrate exemplary gear arrangements for
a dual drive torque multiplier in order to provide equal load
distribution from the drive gears in both the forward and reverse
directions. In particular, the torque multiplier includes a sun
gear 500, which assists to even out the tool action. The dimensions
of the gears may be of any suitable size in order to provide the
desired torque multiplication. In these arrangements, in which the
internal gears area arranged in the same configurations as those
described with reference to Figs. 56, 57 and 59 above respectively,
the torque multiplication is 4:1, rather than the 5:1 shown in Fig.
56. In order to accomplish this, the relative sizes of the gears of
Fig. 56 are altered, while the interaction of the gears remains the
same. In this embodiment, the drive gears 5110, 5100 are
approximately 25mm in diameter and the sun gear is approximately
54mm in diameter.
Figs. 63 and 64 illustrate exemplary gear arrangements for a
dual drive torque multiplier. The dimensions of the gears may be of
any suitable size in order to provide the desired torque
multiplication.
The overall arrangement includes two arrangements as described
with reference to Fig. 56 above, mounted diametrically opposite
about the central sun gear 500, with the exception that only one of
the two arrangements can be driven, the other acts only as a
supplementary arrangement.
Fig. 65 illustrates a torque multiplier that includes two
separate torque multiplication stages. A first torque
multiplication stage, indicated as stage 1 in Fig. 65, may have an
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arrangement of gears as illustrated in Fig. 66. The first stage
shown in Fig. 66 includes a central driven sun gear 6000, which
drives three idler gears 6100, 6110, 6120. The three idler gears
6100 to 6120 each drive two planetary gears 6030 to 6060, set
symmetrically about a notional radius from the centre of the sun
gear 6000 through the centre of the respective idler gear 6100 to
6120. The planetary gears 6030 to 6060 drive an output ring gear
6090, which is integral with an output (520 in Fig. 65). A second
stage, indicated stage 2, is in isolation functionally similar to
embodiments of torque multipliers previously described. The output
of the second stage is connected to the input of the first stage.
It will be appreciated that rotation of the second stage input will
result in a two stage torque multiplication process so that if the
first stage (sun gear based) torque multiplication has a
multiplication factor of 5:1 and the second stage torque
multiplication has a multiplication factor of 4:1, a total torque
multiplication of approximately 20:1 will be achieved. It will
further be appreciated that by using the first stage input drive
510, only the torque multiplication corresponding to the first stage
will be achieved, so that in the illustrated embodiment, a user may
select a torque multiplication of 20:1 or of 5:1. It will further
be appreciated that the second stage torque multiplier could include
a number of torque input portions and could provide a choice of
torque multiplications, for example, 4:1, 5:1 and 6:1. This would
provide the two stage torque multiplier with four different inputs,
one of which could be selected to provide a torque multiplication of
5:1, 20:1, 25:1 or 30:1. Of course, other variations or options
could be provided. It will further be appreciated that more than
two stages could be built into a torque multiplier and Fig. 67
illustrates a three stage torque multiplier. The first and second
stages each give a torque multiplication of 5:1 and the third stage
gives a choice between a direct centre drive or torque inputs giving
a 3:1 or 4:1 torque multiplication. The first and third stages
correspond to the first and second stages described in relation to
Figs . 65 and 66 above, with the first stage being the same as the
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second stage. The total torque multiplication for the three-stage
device is selectably 25:1, 75:1 or 100:1.
It will be appreciated that having two or more stages allows
the torque multiplier to also act as a variable speed tool. For
example, the user could apply the torque multiplier to a nut that is
required to be removed from a bolt at a ratio of 100:1 in order to
initially displace the nut, then switch to a ratio of 75:1 to move
the nut along the thread of the bolt before switching to 25:1 as the
nut is reaching the end of the bolt, and the required torque is
lower. The torque multiplier could also be used as a speed tool
with a winch as described with reference to Figs. 22 to 26.
Alternatively, the use of multiple outputs together with or
instead of multiple inputs allows the torque multiplier tool to be
used as a step up speed tool. For example, if the output and. inputs
are used in reverse, the torque ratio will now be fractional from
input to output; however, the speed with be multiplied. With a tool
with ratios of 25:1, 50:1 and 100:1, six different speedltorque
ratios can be provided.
It will also be appreciated that use of the torque multiplier
as a speed tool is particularly effective with multiple stages due
to the large differences between ratios. However, the torque
multiplier may also be used as a speed tool with any df the
arrangements described in Figs. 1 to 64.
Fig. 68 illustrates a four stage torque multiplier, which is a
three stage multiplier as described with reference to Fig..67, with
an additional stage added before the output. The first, second and
third stages are the same as the first stage described with
reference to Figs. 65 and 66 above, each giving a torque
multiplication of 5:1. The fourth stage gives a choice between
direct centre drive or torque inputs giving a 4:1 or 3:1 torque
multiplication so that the total torque multiplication for the four
stage device is selectably 125:1, 375:1 or 500:1.
Figs. 69a and 69b illustrate an alternative two-stage torque
multiplier. The second stage, indicated as stage 2 in Fig. 69a is
functionally similar to the embodiments of torque multipliers
previously described. The first stage, indicated as stage 1 in fig.
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69a has an arrangement of gears as illustrated in Fig. 69b. In fig.
69a, the first and second stages give a torque multiplication of 5:1
and 4.5:1 respectively. The first and second stages are driven by
first and second input drives 690, 692. Rotation of first input
drive 690 rotates the first stage and results in a one-stage
multiplication of 4.5:1. Rotation of the second input drive 692
rotates the first stage, which, in turn, rotates the second stage
and results in a two-stage torque multiplication of 22.5:1 as
described above with reference to Fig. 65.
Fig. 69b illustrates the arrangement of gears for the first
stage of the torque multiplier of Fig. 69a. The first stage gear
assembly includes a toothed central sun gear 694, an annular double
sided ring gear 696 mounted concentric with the sun gear 694 and
which has teeth on both inner and outer sides. This enables
transmission of force effectively circumferentially about the first
stage of the torque multiplier. A circular outer gear 698 is also
provided, which is toothed on its internal side and mounted radially
outwardly from the ring gear 696 and is concentric to both the sun
gear 694 and the ring gear 696. All the gears are mounted to rotate
about a central axis passing through the notional centre of sun gear
694. The first stage gear assembly further includes internal
planetary drive gears 695 (located between the central sun gear 694
and the ring gear 696) and external planetary drive gears 697
(located between the double sided ring gear 696 and the circular
outer gear 698). The central sun gear 694 is driven directly by the
first input drive 690 or may be indirectly driven by the second
input drive 692 acting on the second stage. The central sun gear
694 drives the internal planetary drive gears 695, which in turn
drive the double sided ring gear 696. The double sided ring gear
696 drives the external planetary drive gears 697 which, in turn
drive the circular output gear 698 at a higher torque than the input
torque applied. The extent of the higher torque is determined by
the size and number of teeth of the various gears.
Fig. 70 shows a further alternative for gearing in a torque
multiplier, with three different torque ratios of 1:1, 2.5:1 and 5:1
within a single tool.
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Fig. 71 shows a two stage torque multiplier including single
direction friction drives to give a torque multiplication of 7:1 or
49:1 depending on whether the central torque input 530 or gear
torque input 540 is used.
Fig. 72a illustrates a torque multiplier generally designated
700 which is generally in the form of a spanner. The tool has an
output gear 702 in a portion corresponding to the spanner head. The
output gear includes a hexagonal cavity for attachment direct to a
nut or other suitable fastener and a square drive cavity 704 for
attachment to a square drive so that it can be driven by, or used to
drive, a wide range of tools and fasteners.
In what would be the handle portion of a normal spanner, the
torque multiplier includes first and second input gears 706, 708.
The second input gear 708 is connected to the output gear 702 by an
idler gear 711. The first input gear is connected via three idler
gears 712, 713, 714 to the second idler gear. A number of screws
715 are illustrated which hold together the casing of the torque
multiplier. The first and second input gears 706, 708 are of
different diameters (and have different numbers of teeth) and both
are considerably smaller (and with fewer teeth) than the output gear
702. The input gears 706, 708 each have a respective square drive
cavity 709, 710. It will be appreciated that the number of idler
gears is provided so that a clockwise rotation of the input gear
706, 708 results in a clockwise rotation of the output gear 702. It
will further be appreciated that due to the size and numbers of
teeth of the gears, a torque multiplication is provided.
Furthermore, it will be appreciated that any torque multiplier of
the types described above could be used to drive one of the input
gears 706, 708 via respective cavities 709, 710 so as to provide a
multiple stage torque multiplying system as shown in Figs 72b, and
72c. A locking mechanism could be provided so that the torque
multiplier 700 could be used as a normal spanner. Alternatively or
additionally, a one-way drive mechanism could be incorporated into
the output gear in order to enhance utility.
Fig. 72d illustrates an alternative embodiment of a torque
multiplier in the general form of a spanner, having an extra pair of
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gears between the input and output gears to that shown in Fig. 72a,
and can receive a torque multiplier of the type discussed above and
shown in Fig. 72e. The output gear may be provided with a hexagonal
cross-sectional cavity and a suitable adaptor having an external
hexagonal shape and a square bore therethrough so as to act as an
adaptor between the hexagonal drive output gear and a square drive
system.
An extension handle may be attached to the torque multiplier
via a socket 730. The extension handle can be used to hinder
rotation of the torque multiplier during use. Figs. 73a, 73b and
73c show three possible extension handles that may be used. Each
has an engaging portion 735 that is insertable to engage with the
socket 730. The engaging portions 735 shown in Figs. 73a and 73c
are mounted on pivoting ends 740 by axles 745, to allow the handle
to extend away from the torque multiplier at various angles.
Additionally, the extension handle shown in Fig. 73a includes
further sockets 750, 755, which can receive an engaging portion from
a further extension handle, so as to provide additional leverage.
The extension handles discussed in relation to Fig 73 may be
used with any of the above described embodiments having one or more
sockets for receiving grounding, extension or bracing members.
Fig. 74 illustrates a locking member for the torque
multipliers of Figs. 72 and 73. A cylindrical torque multiplier
720, as described above in relation to any one of Figs 1 to 21, or
27 to 73, is also provided, together with a removable locking member
724, which joins the two torque multipliers 700, 720 against
relative rotation. The spanner torque multiplier 700 and
cylindrical~torque converter 720 include recesses 725 and 726 that
receive the removable locking member 724. In use, the removable
locking member 724 is inserted into recesses 725 and 726 in order to
stop relative movement of the torque multipliers 700, 720. The
removable locking member 724 is applied to prevent the cylindrical
torque multiplier 720 from rotating relative to the spanner torque
multiplier 700. The removable locking member 724 is held in
recesses 725 and 726 by any suitable means such as a ball and spring
mechanism or via magnetism. The removable locking member 724 also
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includes sockets 728, and an extension handle, as described above,
can be used to engage with the locking member 724, extending away
from the locking member 724, for bracing against rotation of the
combined multipliers 700, 720 when a torque is applied.
Fig. 75 illustrates an alternative .embodiment of a torque
multiplier in accordance with an aspect of the present invention.
The torque multiplier may operate in the same manner as described
above with reference to any of Figs. 1 to 21 or 27 to 73. The
torque multiplier 800 includes a drum 810 which houses the internal
components of the torque multiplier 800 and a base 820, which seals
drum 810. The drum 810 forms a cylinder closed at one end and open
at the other. The base 820 is configured to close the open end of
the drum 810 to seal the internal mechanisms [not shown] of the
torque multiplier 800 in the drum 810. The internal mechanisms may
be as described above with reference to any of Figs. 1 to 21 or 27
to 73 and are all mounted within the drum. As the internal
mechanisms are all mounted to the same mounting frame (i.e. the drum
810), relative positioning of the internal mechanisms is accurate
and not dependent on relative positions of two separate mounting
frames. The base 820 then simply provides a seal for the drum 810,
as the internal mechanisms are not mounted on the base.
The drum and base ,arrangement is more clearly shown in Fig.
76, which illustrates an exemplary two-stage torque multiplier
similar to those discussed above, in which the internal mechanisms
830 are all mounted within the drum 810. The drum 810 and base 820
may be connected by a thread and screw arrangement, via a weld or
another suitable connection to form a seal. Preferably the seal
between the drum 810 and the base 820 is waterproof. The drum 810
and base 820 may be made of aluminium and the aluminium may be
anodized.
The torque multiplier 800 of Figs. 75 and 76 further includes
inputs 801, 802 and 803, and an output 807 [not shown in Fig. 75] .
The inputs 801, 802 and 803 are of different sizes in order to be
able to receive different sized drivers or tools. Surrounding the
inputs 801, 802 and 803 on the outer edge of the drum 810 are
indentations 805. The indentations 805 on the outer edge of the
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drum 810 aid the user in gripping the torque converter for manual
rotation of the torque multiplier 800. The torque converter also
includes a socket 806 located adjacent to the outer edge of the drum
810 surrounding inputs 801, 802 and 803. The socket 806 is circular
in shape and is adapted to receive a bracing rod [not shown] for
bracing against rotation of the torque converter 800 while in use.
Alternatively, other shaped sockets may be provided. A circular
bracing socket is less expensive to machine during manufacture.
Although not shown, further sockets may be included along the outer
edge of the drum 810 to allow better leverage depending on which of
inputs 801, 802 or 803 are being used. The torque multiplier 800
may also be attached to the apparatus for converting torque as
described in Figs. 22 to 26 or 72 and 73.
In the present embodiment, an input torque at input 801 will
drive the output 807 at a ratio of 13:1, and will also drive the
other two inputs 802, 803, which can also be used as outputs for
different torque ratios.
Figs. 77a to 77f show a single-stage torque multiplier 7700
according to an embodiment of the invention. Fig. 77a shows a semi
transparent plan view of a generally cylindrical torque multiplier.
The torque multiplier 7700 has first second and third input portions
7702, 7704, 7706 arranged along a diameter of the cylinder. Fig.
77b shows an axial cross-section of the cylinder of Fig. 77a. The
first input portion 7702 drives an input gear 7712, which drives
idler gears 7714 and supplementary drive gears 7716. The drive and
supplementary drive gears 7712, 7716 drive an output ring gear 7718.
This drive arrangement is as described above with reference to, for
example, Fig. 28.
The third input portion 7706 drives input gear 7720; which
drives output gear 7718 directly, as described, for example, with
reference to Figs 1-9 above. The second input portion 7704 is
connected directly to an output portion (shown as 7728 in Fig. 77c),
which does not change the torque between input and output.
Figs. 77c through 77f show different cross-sections marked on
Fig. 77a. Fig. 77c shows that the cylinder is formed in a similar
manner to that described with reference to Figs. 75 and 76 above, in
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that a drum and base are provided, with all the gear mechanisms
mounted on the drum. Fig. 77c shows journaling 7722 of the second
input portion 7704 to hold it in place in the cylinder, while
allowing it to rotate, as well as base 7724, drum 7726 and output
portion 7728. Fig. 77d shows a retaining screw 7730, which connects
the drum to the base. Fig. 77e shows journaling 7732 on the first
and third input portions 7702, 7706.
In various embodiments of the torque converter described
above, a generally cylindrical unit is described with an input
offset from the cylindrical axis. One or more sockets are provided
into which a removable brace or support member can be inserted.
The brace member serves to hinder rotation of the apparatus
when an input torque is provided, and thus may be any shape and
configuration as is appropriate for the particular use of the
apparatus. In one embodiment, the brace member is a bar, which,
extends, at an angle, to the ground. As the input portion is
rotated in a first direction, by conservation of angular momentum,
the apparatus tries to rotate in the opposite direction. By
positioning the brace member so that the input torque causes
rotation of the apparatus acting partially upwardly about the end of
the brace member distal the apparatus, the weight of the apparatus
is supported by the rotation of the input portion. The tendency of
the apparatus to rotate about the distal end of the brace member
when an input torque is applied means that a separate support
member, acting vertically downwards against gravity, is not
required.
It has also been found that, when the axially offset input
portions are provided, the apparatus is more efficient when the
socket used by the brace member is axially opposite the input
portion in use. Therefore, where multiple axially offset input
portions are provided a socket may be provided axially opposite each
input portion.
It is to be understood that, if any prior art publication is
referred to herein, such reference does not constitute an admission
that the publication forms a part of the common general knowledge in
the art, in Australia or in any other country. Modifications and
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improvements may be incorporated without departing from the scope of
the present invention.
