Note: Descriptions are shown in the official language in which they were submitted.
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FIELD OF THE INVENTION
The present invention relates to a tool for removing bolts and nuts, and in
particular, a ratcheting tool
for bolt or nut removal, which is adjustable to accommodate varying sizes of
bolt heads and nuts.
BACKGROUND OF THE INVENTION
Various tools are used for tightening or loosening bolts and nuts. Two such
tools are an open-ended
wrench and a closed-ended wrench. Both types of wrenches have a specific
opening to accommodate
corresponding size bolt heads or nuts. In order to accommodate different sizes
of bolt heads or nuts,
one would need different wrenches having different corresponding opening
sizes.
One advancement over individual open-ended or closed-ended wrenches is an
adjustable spanner or
wrench having an adjustable opening to accommodate varying sizes of bolts or
nuts, depending on the
adjustment of the jaw opening.
An alternative design to open-ended, closed-ended and adjustable wrenches is a
socket wrench, which
includes a ratchet and a socket end for accepting a plurality of different
size interchangeable sockets.
Each socket is specifically dimensioned to accommodate a specific size bolt
head or nut. An advantage of
a socket wrench is its ratcheting feature which allows selective movement in
either a clockwise or
counterclockwise direction relative to the handle of the wrench thereby
providing for what is know in
the art as a "ratcheting action" to allow one to quickly loosen or tighten a
bolt or nut.
A disadvantage of conventional adjustable wrenches is that they do not provide
a ratcheting action.
Therefore, these wrenches do not allow one to quickly and easily tighten or
loosen a bolt or nut by
rotating the wrench over a desired arc or degree of rotation around the bolt
or nut. A disadvantage with
conventional socket wrenches is that, since the sockets are not adjustable,
one needs a specific socket
for each different size bolt or nut one wishes to adjust. Since bolts and nuts
come in variety of different
sizes including both English and metric units, one needs to have numerous
sockets at his or her disposal
in order to accommodate these different sizes of bolts and nuts.
Accordingly, there is a need in the art for an improved tool which provides
fast and easy bolt and nut
removal using an adjustable tool.
SUMMARY OF THE INVENTION
The present invention meets this need and others with a novel adjustable
ratchet head assembly, and a
novel ratchet wrench device.
The adjustable ratchet head assembly has first and second jaw members that are
connected using a
pinion shaft and a cogwheel shaft. The pinion shaft has oppositely threaded
end portions that engage
oppositely threaded pinion shaft receiving bores in a central section of each
jaw member. The cogwheel
shaft has oppositely threaded end portions that engage oppositely threaded
cogwheel shaft receiving
bores in a proximate end of each jaw member. The jaw members also have a
distal workpiece engaging
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end. Rotation of the pinion shaft and cogwheel shaft will cause the jaw
members to move toward or
away from each other. A pinion gear is concentric with and engages the pinion
shaft. A cogwheel gear is
concentric with and engages the cogwheel shaft, and is in driving engagement
with the pinion gear.
Thus, driving the cogwheel gear will cause rotation of the cogwheel shaft,
pinion gear and pinion shaft,
and will cause the jaw members to move toward or away from each other.
The proximate ends of the jaw members and the cogwheel shaft are received in a
diametrical jaw
member / cogwheel shaft receiving slot of a cylindrical ratchet head body. The
cylindrical ratchet head
body also has a ratchet gear around its circumference.
A handle assembly of the invention has a ratchet head receiving structure and
a pawl assembly. The
cylindrical ratchet head body is received in the handle assembly ratchet head
receiving structure. The
pawl assembly cooperates with the ratchet gear to allow rotation of the
ratchet head assembly with
respect to the handle assembly in one direction and to prevent rotation of the
ratchet head assembly in
the other direction.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail with reference to the
accompanying drawing, in
which:
FIG. 1 is a perspective view of an exemplary adjustable ratchet wrench device
according to the
invention;
FIG. 2 is an exploded view of the primary components of the adjustable ratchet
wrench device of FIG. 1;
FIG. 3a is a top view of selected parts of an exemplary ratchet head assembly,
pawl assembly, and
interior handle member according to various aspects of the invention (an
exemplary bottom handle
member is partially show in broken line representation);
FIG. 3b is a side view of the exemplary ratchet head assembly of FIG. 3a;
FIG. 3c is a bottom view of the exemplary ratchet head assembly of FIG. 3a;
FIG. 4 is a partial sectional view of an exemplary ratchet head assembly
according to an aspect of the
invention (for clarity of understanding, selected elements are shown in
section while other elements are
shown in plan); and
FIG. 5 is a perspective view of an exemplary hand grip member according to an
aspect of the invention.
DETAILED DESCRIPTION
As shown in FIG. 1, an exemplary embodiment of an adjustable ratchet wrench
device 10 according to
the invention has, generally, a handle assembly 12 and an adjustable ratchet
head assembly 14. Visible
elements of the handle assembly 12 include a handle section 16, a hand grip
member 18 covering a
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portion of the handle section 16, a top handle member 20, a bottom handle
member 21, a spacer
member 22, and a rotation direction lever 24 of a pawl assembly. Visible
elements of the ratchet head
assembly 14 include first and second opposing jaw members 26, 27, a pinion
shaft 28, a gear shield 30, a
protector cap 32, and a thumbwheel 34.
Driving the thumbwheel 34 will move the jaw members 26, 27 toward each other
or away from each
other, according to the direction of rotation of the thumbwheel 34. The jaw
members 26, 27 may be
moved away from each other to accommodate a bolt head or nut, and then moved
toward each other
to engage the bolt head or nut for tightening or loosening. The handle
assembly 12 holds the ratchet
head assembly 14 fixed in one direction of rotation, and allows the ratchet
head assembly 14 to freely
rotate in the other direction of rotation, so that the handle assembly 12 can
be brought back to recover
the stroke without removing the jaw members 26, 27 from the bolt head or nut.
The rotation direction
lever 24 determines whether ratchet head assembly 14 is fixed in the clockwise
or counter-clockwise
direction with respect to the handle assembly 12, and allows the direction to
be switched for tightening
or loosening of the bolt or nut.
FIG. 2 is an exploded view of the exemplary adjustable ratchet wrench device
10. The adjustable ratchet
head assembly 14 has first and second opposing jaw members 26, 27, a pinion
shaft 28 having a pinion
gear 36, a cogwheel shaft 38 having a cogwheel gear 40, a ratchet head body
42, a rotation pin 44, a
gear shield 46, and a protector cap 32. The handle assembly 12 has a top
handle member 20, a bottom
handle member 21, an interior handle member 50, a spacer member 22, and a pawl
assembly 52.
Each of the first and second opposing jaw members 26, 27 is an elongate
structure having a longitudinal
axis and having a distal end 56, 57, a central section 58, 59, and a proximate
end 60, 61. The distal end
56, 57 of each jaw member 26, 27 is the end that engages the bolt head, nut,
or other workpiece. Each
central section 58, 59 has a threaded pinion shaft receiving bore 62, 63 that
is perpendicular to the
longitudinal axis and extends through the member 26, 27. Each threaded pinion
shaft receiving bore 62,
63 is threaded in an opposite direction from the other pinion shaft receiving
bore 63, 62. Each proximate
end 60, 61 has a threaded cogwheel receiving bore 64, 65 that is parallel to
the pinion shaft receiving
bore 62, 63 and also extends through the member 26, 27. Each threaded cogwheel
receiving bore 64, 65
is also threaded in an opposite direction from the other cogwheel receiving
bore 65, 64.
The pinion shaft 28 has oppositely threaded end portions 66, 67 and a central
portion 68. The pinion
gear 36 is concentric with and engages the central portion 68 of the pinion
shaft 28 between the
oppositely threaded end portions 66, 67, such that when the pinion gear 36 is
driven, the pinion shaft 28
will rotate. The pinion gear 36 may be integral with the pinion shaft 28, or
may be otherwise fastened,
attached, affixed, joined, connected, or coupled to the pinion shaft 28. Each
of the pinion shaft
oppositely threaded end portions 66, 67 is received in and threadedly engaged
with a respective jaw
member threaded pinion shaft receiving bore 62, 63, such that rotation of the
pinion shaft 28 in the
pinion shaft receiving bores 62, 63 will cause the jaw members 26, 27 to move
toward or away from
each other.
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The cogwheel shaft 38 also has oppositely threaded end portions 70, 71 and a
central portion 72. The
cogwheel gear 40 is concentric with and engages the central portion 72 of the
cogwheel shaft 38
between the oppositely threaded end portions 70, 71, such that when the
cogwheel gear 40 is driven,
the cogwheel shaft 38 will rotate. The cogwheel gear 40 may be integral with
the cogwheel shaft 38, or
may be otherwise fastened, attached, affixed, joined, connected, or coupled to
the cogwheel shaft 28.
Additionally, the cogwheel shaft 38 has a rotation pin receiving bore 74
through a longitudinal axis of
the cogwheel shaft 38. Each of the cogwheel shaft oppositely threaded end
portions 70, 71 is received in
and threadedly engaged with a respective jaw member cogwheel shaft receiving
bore 64, 65, such that
rotation of the cogwheel shaft 38 in the cogwheel shaft receiving bores 64, 65
will cause the jaw
members 26, 27 to move toward or away from each other. The cogwheel shaft 38
and pinion shaft 28
have a parallel configuration and are perpendicular to the longitudinal axes
of the first and second
opposing jaw members 26, 27.
The pinion shaft receiving bores 62, 63, cogwheel shaft receiving bores 64,
65, pinion shaft 28, pinion
gear 36, cogwheel shaft 38 and cogwheel gear 40 are located and scaled such
that the cogwheel gear 40
engages the pinion gear 36. The cogwheel gear 40 is also referred to as a
"thumbwheel 34" because in
use, it is driven by a user's thumb to open and close the jaw members 26, 27.
When the user drives the
cogwheel gear / thumbwheel 40 (34), the parallel pinion shaft 28 and cogwheel
shaft 38 rotate and the
jaw members 26, 27 ride on the pinion shaft 28 and cogwheel shaft 38 toward or
away from each other.
Advantageously, the parallel pinion shaft 28 and cogwheel shaft 38 arrangement
provides smooth,
stable, even and easy adjustment of the jaw members 26, 27, and adds clamping
force to counter the
rotational moments created when the distal, workpiece engaging ends 56, 57 of
the jaws 26, 27 are
tightened around a bolt head, nut, or other workpiece. The gears and threads
are also selected to
maintain the jaw members 26, 27 in a proportional relationship. In the
exemplary embodiment, the
cogwheel gear 40 and threaded end portions 70, 71 of the cogwheel shaft 38
have a ratio with the
pinion gear 36 and threaded end portions 66, 67 of the pinion shaft 28 such
that one revolution of the
cogwheel gear 40 will advance the pinion gear 36 two revolutions.
As shown in FIG. 3a, FIG. 3b, FIG. 3c, and FIG. 4, the ratchet head body 42
has a generally cylindrical
body 76, a diametrical jaw member / cogwheel shaft receiving slot 78 for
receiving the proximate ends
60, 61 of the jaw members 26, 27 and the cogwheel shaft 38, a diametrical
cogwheel gear receiving slot
80 for receiving the cogwheel gear 40, a rotation pin 44 (shown in FIG. 2 and
in broken line
representation in FIG. 4), and a ratchet gear 84. The cogwheel gear receiving
slot 80 is transverse to the
jaw member / cogwheel shaft receiving slot 78. The ratchet head body 42 is
positioned around the
proximate ends 60, 61 of the jaw members 26, 27, the cogwheel shaft 38, and
the cogwheel gear 40
such that the proximate ends 60, 61 of the jaw members 26, 27 and the cogwheel
shaft 38 are received
in the jaw member / cogwheel shaft receiving slot 78, and such that the
cogwheel gear 40 is received in
the cogwheel gear receiving slot 80. A portion of the cogwheel gear 40
protrudes from the ratchet head
body 42 to act as a thumbwheel 34.
Shown in FIG. 2 and FIG. 4, the ratchet head body 42 also has a diametrical
rotation pin receiving bore
86 aligned with the jaw member / cogwheel shaft receiving slot 78 and with the
cogwheel shaft rotation
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pin receiving bore 74. The rotation pin 44 extends through the ratchet head
body rotation pin receiving
bore 86 and the cogwheel shaft rotation pin receiving bore 74 to rotatably
couple the cogwheel shaft 38
to the ratchet head body 42.
Shown in FIG. 2 through FIG. 4, the ratchet gear 84 engages the circumference
of the ratchet head body
5 42, such that jamming of the ratchet gear 84 will prevent rotation of the
ratchet head body 42. The
ratchet gear 84 may be integral with the ratchet head body 42, or may be
otherwise fastened, attached,
affixed, joined, connected, or coupled to the ratchet head body 42.
Additionally, the ratchet head body 42 has a diametrical gear shield receiving
bore 88 aligned with the
cogwheel gear receiving slot 80 along a lower portion of the ratchet head body
42, and a protector cap
lip receiving groove 90 positioned around a top portion of the ratchet head
body 42.
The gear shield member 46 is received in the openings of the ratchet head body
gear shield receiving
bore 88 on the inside of the cogwheel receiving slot 80. The gear shield
member 46 covers and protects
the cogs or teeth of the pinion gear 36 from damage from the workpiece or
other objects that may pass
between the jaw members 26, 27. In the exemplary embodiment, the gear shield
member 46 has a one-
piece construction and follows the curvature of the pinion gear 36. The gear
shield member 46 is
resilient, which allows it to be flexed such that its ends can be inserted
into the openings of the ratchet
head body shield receiving bore 88 on the inside of the cogwheel receiving
slot 80.
Similarly, best shown in FIG. 4, the protector cap 32 protects the top portion
of the ratchet head body
42 and the cogwheel gear 40. The protector cap 32 is sized to fit over the top
portion of the ratchet
head body 42, and has a concave upper wall. The protector cap 32 protects the
cogwheel gear 40,
provides comfort for the user's thumb, and provides an aesthetic benefit (i.e.
makes it "meaner
looking") to the ratchet wrench device 10. The protector cap 32 has a
cylindrical side wall 92 having an
inner surface 94. A lip 96 extends from the inner surface 94, and cooperates
with the protector cap lip
receiving groove 90 positioned around the top portion of the ratchet head body
42 to hold the protector
cap 32 to the ratchet head body 42.
Returning now to FIG. 2, the top handle member 20 and bottom handle member 21
have aligned ring
portions 98, 99 in spaced relation forming a ratchet head receiving structure.
The interior handle
member 50 and the spacer member 22 hold the top handle member 20 and bottom
handle member 21
in such spaced relation. The ratchet head body 42 is received within the
ratchet head receiving structure
with the ratchet gear 84 positioned in the space between the top handle member
ring portion 98 and
bottom handle member ring portion 99 such that the ratchet head assembly 14 is
rotatably coupled to
the handle assembly 12. The spacer member 22 has a height greater than the
width of the ratchet gear
84 to facilitate rotation of the ratchet head assembly 14 in the ratchet head
receiving structure of the
handle assembly 12.
Shown in FIG. 2 and FIG. 3a, the pawl assembly 52 cooperates with the ratchet
gear 84 to allow rotation
of the ratchet head assembly 14 with respect to the handle assembly 12 and to
prevent rotation of the
ratchet head assembly 14 in the other direction. The pawl assembly 52 has a
double pawl member 100,
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a rotation direction lever 24, and a biasing member 102. The double pawl
member 100 has opposed
pawls 104, 105 and a pivot pin 106 extending through or from top and bottom
surfaces of the double
pawl member 100. The pivot pin 106 extends through aligned holes 108, 109 in
the top handle member
20 and bottom handle member 21, respectively, to engage the double pawl member
100 and to pivot
one of the pawls 104, 105 against the ratchet gear 84. The pivot pin 106 may
engage the double pawl
member 100 through a flat spot or other irregular shape in the pin 106 which
acts on a mating opening
in the double pawl member 100. Alternatively, the pivot pin 106 may be
integral with the double pawl
member 100. The rotation direction lever 24 is attached to the portion of the
pivot pin 106 extending
through the hole 108 in the top handle member 20. The biasing member 102
applies a biasing force to
the double pawl member 100 to bias one of the opposed pawls 104, 105 against
the ratchet gear 84,
which jams the ratchet gear 84 in one direction of rotation, and allows
movement in the other direction
of rotation. Thus, the biasing member 102 holds the double pawl member 100 in
the selected
orientation until a changing force is applied to the rotation direction lever
24 to overcome the biasing
force and change the direction of allowable rotation of the ratchet head
assembly 14.
In the exemplary embodiment, the biasing member is a spring 110 and ball
bearing 112 assembly. The
spring 110 and ball bearing 112 assembly is positioned in a cavity 114 in the
interior handle member 50
adjacent the double pawl member 100. The double pawl member 100 has a head 116
and bearing
notches 118, 119 on either side of the head 116. The head 116 is opposed to
the opposed pawls 104,
105, in a substantially triangular arrangement. The spring 110 and ball
bearing 112 assembly cooperates
with the head 116 and bearing notches 118, 119 such that the ball bearing 112
is biased against the
double pawl member 100 in one of the bearing notches 118, 119 to provide the
biasing force.
The top handle member 20, bottom handle member 21, and interior handle member
50 are held
together by fasteners, such as rivets, as needed.
As shown in FIG. 1 and FIG. 5, the hand grip member 18 of the exemplary
embodiment is a boot that
slides over a portion of the handle section 16 of the handle assembly 12, to
provide ergonomic
adaptation of the ratchet wrench device 10 to a human hand. Advantageously,
the end of the hand grip
member 18 may contain a socket 120 for holding a tool bit.
Additionally, the words "right" and "left" may be added to the top handle
member 20 adjacent the
rotation direction lever 24 to provide a visual indication with the lever 24
pointing to the direction of
fixed rotation of the ratchet wrench device 10. Likewise, the words "open" and
"close" may be added to
the protector cap 32 to provide a visual indication of the rotation direction
of the thumbwheel 34 to
open and close the jaw members 26, 27.
Referring now to FIG. 2, the inner surfaces 122, 123 of the jaw members 26, 27
can be magnetized to
allow for positioning of a screw-driver bit for use of the device as a
standard screw driver.
Although the invention has been described in considerable detail with respect
to exemplary
embodiments, it will be apparent to those skilled in the art that the
invention is capable of numerous
modifications and variations without departing from the spirit and scope of
the claimed invention.
