Note: Descriptions are shown in the official language in which they were submitted.
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"Tooth and Adaptor Assembly"
Field of the Invention
This invention relates particularly to the mining and construction industries
and the
use of earthmoving and similar machinery used in those industries. More
particularly this invention relates to the wear components, namely the
replaceable
wear teeth on the excavator and the mode in which they are secured thereto.
Background Art
Within the mining and construction industries machinery such as excavators and
front end loaders are used to move debris for various purposes. This machinery
is often used in an extremely abrasive environment resulting in extreme wear
on
components.
The machinery often has a bucket having several teeth extending from its
leading
edge. These teeth experience substantial wear and may need to be replaced
daily in some environments.
To reduce downtime in replacing the teeth, various configurations have been
developed which use an adaptor secured to the bucket of the machine, a tooth
releasably retained on the adaptor and a locking mechanism to retain the tooth
to
the adaptor.
These configurations have been numerous. However, the configurations put
forward to date are not without disadvantages. For instance, various
configurations utilise a pin as the locking mechanism to secure the tooth to
the
adaptor. These pins are often exposed to the same environment the tooth is
exposed, requiring that they be very secure with respect to the assembly so
that
they are not accidentally dislodged during use. Typically in order to meet
this
requirement, a large force is then required to dislodge the pin when the tooth
is to
be removed. Furthermore, the pins exposure to the environment can result in
damage to the pin rendering it even more difficult to dislodge.
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Other configurations are complex in shape, often having large areas of metal
extending beyond the main body of the tooth. These shapes can be difficult to
cast and may result in the build up of stresses within the adaptor or tooth
during
casting, creating weak points within the components. Also, the extra metal
does
not always contribute to extending the wear life of the tooth and hence adds
unnecessary weight to the assembly.
Also, complementary shapes to those of the tooth also need to be cast in the
adaptor, typically in the form of grooves or indents. These grooves and
indents
are typically used to receive the locking mechanism within, which co-acts with
the
two components. The cross section of 'the adaptor must therefore change
significantly to accommodate these complimentary shapes, resulting in
concentrations of stress during manufacture and service of the corriponent.
Some configurations put forward in the past require a hole passing through the
adaptor. This obviously weakens the structure and induces areas of stress
within
the component.
The reference to the abovementioned prior art is for the purposes of
background
only and is not, and should not be taken as, an acknowledgement or any form of
suggestion that the prior art forms part of the general knowledge.
It is an object of this invention to provide a tooth and adaptor assembly
which
20, incorporates a locking mechanism which can be removed from the assembly
with
minimal force.
Disclosure of the Invention
The present invention provides a tooth and adaptor assembly for use on
earthmoving machinery, the assembly comprising:
an adaptor adapted to be secured to a bucket or like component on
earthmoving machinery, the adaptor comprising a nose at one end having
a front surface, an upper surface, a lower surface and two sidewalls, each
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sidewall having a first channel extending longitudinally, and a second
channel extending between the upper surface of the nose to the lower
surface such that it bisects the first channel;
a tooth adapted to be received over the nose of the adaptor, and releasably
secured thereto, the tooth comprising
a socket being defined by an opening, a rear surface, an upper wall,
a bottom wall and two sidewalls,
each sidewall incorporates a third channel extending between
the upper wall and bottom wall and being at an angle
complementary to the second channel of the nose, such that
when assembled, the second channel and third channel co-
operate to define an enclosure, each sidewall also has an
inwardly projecting elongate protrusion adapted to be slidingly
received in the first channel of the adaptor nose during
assembly, and an inwardly projecting tab adjacent the
opening and in longitudinal alignment with the elongate
protrusion, the third channel separating the elongate
protrusion and tab,
the upper wall having two apertures therethrough, each
aperture aligning with the respective third channel;
a locking mechanism for locking the tooth to the adaptor, the locking
mechanism being adapted to be received through the apertures, each
locking mechanism having a projection,
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of both the upper wall and bottom wall of
the
socket engages the upper surface and lower surface of the nose, the locking
mechanism can then be inserted into the enclosure defined by the second
channel and third channel through the aperture, whereby the projection of the
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locking mechanism moves inwardly with respect to the locking mechanism as it
enters the enclosure, the locking mechanism moving towards its normal extended
position when the projection aligns with the first channel wherein the
assembly is
in a locked condition.
In contrast with the prior art the present invention provides a configuration
which
is easy to cast, reducing regions of high stress. Furthermore, the locking
mechanism is fully enclosed, protecting it from the abrasive surroundings
which
could damage the mechanism and make removal extremely difficult.
As the locking mechanism is fully enclosed in the enclosure, there is no
chance
that the mechanism can be unintentionally dislodged and allow the tooth to be
removed from the adaptor, to expose the adaptor to the environment. As the
locking mechanism is protected, the forces required to retain the locking
mechanism are greatly reduced than prior art configurations, and hence
requires
minimal force to remove the locking mechanism, enabling quick change out time,
reducing the amount of downtime of the machinery.
Owing to the design of the present invention, the entire tooth is used as a
wear
protection element for the adaptor. Hence there is no additional weight added
to
the tooth which would not prolong its life.
Also, the shape of the tooth allows for easy casting, reducing areas of
increased
stress, which may cause failure of the assembly during service. This is true
for
the tooth but also for the adaptor. The simple shape of the nose of the
adaptor
represents minimal change to its cross sectional shape and allows the socket
of
the tooth to be manufactured such that it is snugly received on the nose.
The locking mechanism may comprise two pins.
Each pin may be adapted to be received in the respective aperture in the upper
wall of the tooth.
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Each pin may comprise a housing and a retaining clip which provides the
projection.
The retaining clip may be bonded to a resiliently flexible material.
The resiliently flexible material may be received in a recess of the housing.
The projection may extend beyond the boundary of the housing when the pin is
in
its normal condition.
The housing may be made of metal.
Preferably, when the tooth and adaptor are in an assembled condition, each pin
engages a front surface of the second channel closest to the front of the
nose,
with a portion of the retaining clip adjacent the projection engaging a rear
face of
the second channel adjacent either side of the first channel. When assembled,
neither the rear surface of the socket, nor the rear part of the tooth
adjacent the
socket opening engage the adaptor.
Preferably when in an assembled condition each pin does not protrude beyond
the upper wall or bottom wall of the tooth.
Preferably the front face of the adaptor nose is rectangular in shape.
Preferably the nose diverges outwardly, in a direction rearward of the front
face.
Preferably the upper surface and lower surface of the nose are curved.
Preferably the first channel of the adaptor extends from adjacent a front face
of
the nose rearwardly.
The first channel may be parallel with the path the tooth travels as the tooth
is
positioned upon the adaptor.
Preferably the second channel is substantially perpendicular to the first
channel.
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Preferably the second channel bisects the first channel.
Preferably the second channel has a wider portion adjacent the upper surface
which contracts as it approaches the first channel.
Preferably the portion of the second channel above the first channel is wider
near
the upper surface and has a inwardly raised ramp adjacent the first channel.
The
additional width of the second channel allows the pin to be easily positioned
within
the assembly. Once in this position, the fitter only needs to tap the pin,
forcing the
retaining clip to move inwardly with respect to the housing of the pin as it
engages
the ramp. Once the projection passes the ramp, the resilient nature of the pin
urges the retaining clip outwardly such that the assembly is in the locked
condition.
Preferably the tooth is a unitary member and provides the wear member.
Preferably the interior surfaces of the socket complement the surfaces of the
nose.
Preferably the upper wall and bottom wall of the tooth have a curved section
which protrudes beyond the sidewalls. The curved section adds further wear
protection to the adaptor.
Preferably the elongate protrusion extends between the third channel and the
rear
surface of the socket.
Preferably the third channel is substantially perpendicular to the protrusion.
The protrusion may be parallel with the path the tooth travels as the tooth is
positioned upon the adaptor.
Preferably the elongate protrusion extends substantially parallel to the
longitudinal
axis of the tooth.
Preferably the third channel has a uniform cross section along its
longitudinal axis.
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Preferably the tab of the tooth is offset from the third channel. As a result
of the
offset, a recess may be provided by the first channel of the adaptor when the
adaptor is received in the tooth, the recess being defined by a portion of the
first
channel of the adaptor adjacent the second channel.
Preferably the projection from the pin is releasable retained in the recess to
hold
the pin in place when the assembly is in an assembled condition. In this state
the
assembly is in the locked condition.
Preferably the bottom wall of the tooth incorporates two apertures.
In one aspect of the invention each aperture in the bottom wall is aligned
with the
third channel and is of sufficient size to allow the respective pin to pass
through.
With this arrangement, the assembly can be disassembled by knocking the pin
through the aperture in the bottom wall.
In another aspect of the invention the apertures in the bottom wall are of
suitable
size such that the pins cannot pass therethrough. To remove each pin, a tool
may
be inserted through each aperture of the bottom wall to dislodge the pins,
allowing
the pin to be removed through the apertures in the upper wall.
The present invention further provides a tooth for use on an adaptor of
earthmoving machinery, the tooth being adapted to be received over a nose of
the
adaptor and releasably secured thereto, the tooth comprising:
a socket being defined by an opening, a rear surface, an upper wall, a
bottom wall and two sidewalls,
each sidewall incorporates a channel extending between the upper
wall and bottom wall, an inwardly projecting elongate protrusion and
an inwardly projecting tab adjacent the opening and in longitudinal
alignment with the elongate protrusion, the channel extending
between the elongate protrusion and tab,
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the upper wall having two apertures therethrough, each aperture
aligning with the respective channel;
the bottom wall having two apertures in alignment with those in the
upper wall;
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of both the upper wall and bottom wall of
the
socket engage the nose whereby the adaptor and each channel of the tooth
cooperate to provide an enclosure, a locking mechanism is then positioned
within
the enclosure such that a projection of the locking mechanism is received in a
recess provided by the adaptor, locking the tooth relative to the adaptor.
The present invention further provides a tooth and adaptor assembly for use on
earthmoving machinery, the assembly comprising:
an adaptor adapted to be secured to a bucket or like component on the
earthmoving machinery, the adaptor comprising a nose at one end having
a front surface, an upper surface, a lower surface and two sidewalls, each
sidewall having a first channel extending longitudinally, and a second
channel extending between the upper surface of the nose to the lower
surface such that it bisects the first channel;
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that a surface of a socket of the tooth engages the nose whereby
the second channel of the adaptor and the tooth co-operate to provide an
enclosure, a locking mechanism is then positioned within the enclosure such
that
a projection of the locking mechanism is received in a recess defined by the
first
channel, locking the tooth relative to the adaptor.
The present invention further provides a tooth and adaptor assembly for use on
earthmoving machinery, the assembly comprising:
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an adaptor adapted to be secured to a bucket or like component on
earthmoving machinery, the adaptor comprising a nose at one end having
a front surface, an upper surface, a lower surface and two sidewalls, at
least one sidewall having a first channel extending longitudinally, and a
second channel extending between the upper surface of the nose to the
lower surface such that it bisects the first channel;
a tooth adapted to be received over the nose of the adaptor, and releasably
secured thereto, the tooth comprising
a socket being defined by an opening, a rear surface, an upper wall,
a bottom wall and two sidewalls,
at least one sidewall, complementary to the at least one
sidewall of the adaptor, incorporates a third channel
extending between the upper wall and bottom wall and being
at an angle complementary to the second channel of the
nose, such that when assembled, the second channel and
third channel co-operate to define an enclosure,
the upper wall having at least one aperture therethrough, the
at least one aperture aligning with the third channel of the
sidewall;
the at least one sidewall having an inwardly projecting
elongate protrusion adapted to be slidingly received in the
first channel of the adaptor nose during assembly, and an
inwardly projecting tab adjacent the opening and in
longitudinal aiignment with the elongate protrusion, the third
channel separating the elongate protrusion and tab,
at least one locking mechanism for locking the tooth to the adaptor, the
locking mechanism being adapted to be received through the at least one
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aperture, the at least one locking mechanism having at least one
projection,
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of both the upper wall and bottom wall of
the
socket engages the upper surface and lower surface of the nose whereby the
second channel of the adaptor is in opposed relation to the third channel of
the
tooth, the locking mechanism is then positioned through the aperture into the
enclosure, whereupon the application of force, the projection of the locking
mechanism moves inwardly as it enters the enclosure, the locking mechanism
moves towards its normal condition whereby the projection aligns with the
first
channel wherein the assembly is in its locked condition.
The present invention further provides a tooth and adaptor assembly for use on
earthmoving machinery, the assembly comprising a tooth received on an adaptor,
the tooth being locked onto the adaptor by a locking mechanism, whereby the
locking mechanism comprises at least one pin received in an enclosure defined
by the tooth and the adaptor, the enclosure being such that the at least one
pin is
protected from the environment and can only be removed via an aperture through
which it is received into the enclosure.
The present invention still further provides a tooth and adaptor assembly for
use
on earthmoving machinery, the assembly comprising:
an adaptor adapted to be secured to a bucket or like component on the
earthmoving machinery, the adaptor comprising a nose at one end having
a front surface, an upper surface, a lower surface and two sidewalls, each
sidewall having a first channel extending longitudinally, and a second
channel extending between the upper surface of the nose to the lower
surface such that it bisects the first channel;
a tooth adapted to be received over the nose of the adaptor, and releasably
secured thereto, the tooth comprising
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a socket being defined by an opening, a rear surface, an upper wall,
a bottom wall and two sidewalls,
each sidewall incorporates a third channel extending between
the upper wall and bottom wall and being at an angle
complementary to the second channel of the nose, such that
when assembled, the second channel and third channel
define an enclosure,
the upper wall having two apertures therethrough, each
aperture aligning with the respective third channel on each
sidewall;
each sidewall has an inwardly projecting portion adapted to
be slidingly received in the first channel of the adaptor nose
during assembly,
a locking mechanism for locking the tooth to the adaptor, the locking
mechanism being adapted to be received through the apertures, each
locking mechanism having a projection,
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of the upper wall and bottom wall of the
socket
engages the upper surface and lower surface of the nose whereby the first
channel of the adaptor is in opposed relation to the third channel of the
tooth, the
locking mechanism is then positioned through the aperture into the enclosure,
whereupon the application of force, the projection of the locking mechanism
moves inwardly with respect to the locking mechanism as it enters the
enclosure,
the locking mechanism moves towards its normal condition when the projection
aligns with the first channel wherein the assembly is in its locked condition.
Preferably the portion is in the form of a tab adjacent the opening of the
socket.
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The present invention further provides a tooth for use on an adaptor of
earthmoving machinery, the tooth being adapted to be received over a nose of
the
adaptor, and releasably secured thereto, the tooth comprising:
a socket being defined by an opening, a rear surface, an upper wall, a
bottom wall and two sidewalls,
each sidewall incorporates a channel extending between the upper
wall and bottom wall,
the upper wall having two apertures therethrough, each aperture
aligning with the respective channel on an inner surface of each
sidewall;
the bottom wall having two apertures in alignment with those in the
upper wall;
the inner surface of each sidewall having an inwardly projecting
portion,
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of the upper wall and bottom wall of the
socket
engage the nose whereby the adaptor and each third channel of the tooth co-
operate to provide an enclosure, a locking mechanism is then positioned within
the enclosure such that a projection of the locking mechanism is received in a
recess defined by the adaptor, locking the tooth relative to the adaptor.
Preferably the portion is in the form of a tab adjacent the opening of the
socket.
The present invention further yet provides a tooth and adaptor assembly for
use
on earthmoving machinery, the assembly comprising:
an adaptor adapted to be secured to a bucket or like component on the
earthmoving machinery, the adaptor comprising a nose at one end having
an upper surface, a lower surface and two sidewalls, at least one sidewall
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having a first channel extending longitudinally, and a second channel
extending between the upper surface and the lower surface such that it
bisects the first channel;
a tooth adapted to be received over the nose of the adaptor, and releasably
secured thereto, the tooth comprising
a socket being defined by an upper wall, a bottom wall and two
sidewalls,
at least one sidewall incorporates a third channel extending
between the upper wall and bottom wall and being at an
angle complementary to the second channel of the nose,
such that when assembled, the second channel and third
channel co-operate to define an enclosure, the at least one
sidewall also has an inwardly projecting protrusion adapted to
be slidingly received in the first channel of the adaptor nose
during assembiy,
the upper wall having at least one aperture therethrough,
aligned with the third channel;
at least one locking mechanism for locking the tooth to the adaptor, the
locking mechanism being adapted to be received through the aperture, the
at least one locking mechanism having at least one projection,
wherein during assembly the tooth is slidingly positioned over the nose of the
adaptor such that the inner surface of both the upper wall and bottom wall of
the
socket engages the upper surface and lower surface of the nose whereby the
second channel of the adaptor is in opposed relation to the third channel, the
locking mechanism can then be inserted into the enclosure through the
aperture,
whereby the projection of the locking mechanism moves inwardly with respect to
the locking mechanism as it enters the enclosure, the locking mechanism moving
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towards its normal extended position when the projection aligns with the first
channel wherein the assembly is locked together.
Brief Description of the Drawings
The invention will be better understood by reference to the following
description of
two embodiments of the invention, as shown in the accompanying drawings in
which:
Figure 1 is a rear perspective view of a tooth according to a first
embodiment of the invention;
Figure 2 is a cross sectional plan view of figure 1;
Figure 3 is a cross sectional side view of figure 1
Figure 4 is a cross sectional perspective view of figure 1 from a rear
position;
Figure 5 is a cross sectional perspective view of figure 1 from a forward
position;
Figure 6 is a view similar to figure 5 from an elevated position;
Figure 7 is a view similar to figure 4 from a lower position;
Figure 8 is an exploded view of section A as shown in figure 7;
Figure 9 is a front perspective view of an adaptor according to an
embodiment of the invention;
Figure 10 is a view similar to figure 9, but only showing the nose section;
Figure 11 is a cross sectional plan view of figure 10;
Figure 12 is a front view of figure 9;
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Figure 13 is a side view of figure 9;
Figure 14 is a bottom view of figure 9;
Figure 15 is a cross sectional view of a locking mechanism according to an
embodiment of the invention;
Figure 16 is a cross sectional view of the tooth received on the nose of the
adaptor, with the locking mechanism partially inserted in an enclosure;
Figure 17 is a view similar to figure 16 with the locking mechanism
positioned further in the enclosure;
Figure 18 is a view similar to figure 16 with the assembly in a locked
position.
Figure 19 is a view similar to figure 16 with the locking mechanism passing
through a bottom aperture;
Figure 20 is a rear perspective view of a tooth according to a second
embodiment of the invention;
Figure 21 is a cross sectional plan view of figure 20;
Figure 22 is a cross sectional view of the tooth according to the second
embodiment received on the nose of the adaptor, with the locking
mechanism partially inserted in an enclosure; and
Figure 23 is a view simiiar to figure 22 with the assembly in a locked
position.
Best Mode(s) for Carrying Out the Invention
Referring to the figures 1 to 19, the invention according to a first
embodiment of
the invention comprises a tooth and adaptor assembly 11 for use on earthmoving
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or similar machinery. The assembly 11 comprises an adaptor 21, having a first
end 23 adapted to receive a tooth 41, with a locking mechanism 71 being
received therein to lock the tooth 41 relative to the adaptor 21.
Shown in figures 9 to 14 is the adaptor 21. The adaptor 21 has a second end 25
adapted to be secured to a bucket or like component on the earthmoving
machinery (not shown). The configuration of the second end 25 varies according
to its particular application.
The adaptor 21 comprises a nose 27 at the first end 23. The nose 27 diverges
outwardiy in a rearward direction from a front surface 29. The nose 27
comprises
an upper surface 31, a lower surface 33, both having a curved contour, and two
sidewalls 35.
Each sidewall 35 incorporates a first channel 37 extending longitudinally
along the
nose 27 rearward from the front surface 29, and a second channel 39 extending
between the upper surface 31 of the nose 27 to the lower surface 33 such that
it
bisects the first channel 37 and is substantially perpendicular thereto.
The portion of the second channel 39 above the first channel 37 comprises a
wider portion 41 than the lower part of the second channel 39, and a ramp 40
adjacent the first channel 37, as best shown in figures 10 and 13, for reasons
which are explained below.
Shown in figures 1 to 8, is the tooth 41. The tooth 41 is adapted to be
received
over the nose 27 of the adaptor 21, to be releasably secured thereto. The
tooth
41 comprises a socket 43 being defined by an opening 45, a rear surface 47, an
upper wall 49, a bottom wall 51 and two sidewalls 53. The shape of the socket
43
complements the surface of the nose 27 to provide a snug fit when the tooth 41
is
received on the adaptor 21.
Each sidewall 53 incorporates a third channel 55. The third channel 55 is
substantially parallel to the opening 45 such that when assembled, the second
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channel 39 of the nose 27 and third channel 55 co-operate to define an
enclosure
91.
The upper wall 49 has two apertures 57a therethrough. Each aperture 57a is in.
alignment with the respective third channel 55 on each sidewall 53.
The bottom wall 51 also has two apertures 57b. These apertures 57b are the
same size and in alignment with the two apertures 57a of the upper wall 49.
Each sidewall 53 also provides an inwardly projecting elongate protrusion 59
adapted to be slidingly received in the first channel 37 of the adaptor nose
27
during assembly of the tooth 41 and adaptor 21. The elongate protrusion 59
extends between the third channel 55 and the rear surface 47 of the socket 43,
and is substantially perpendicular to the third channel 55.
The inner surface of each sidewall 53 also provides a tab 61 protruding into
the
opening 45, and which is in longitudinal alignment with the elongate
protrusion 59.
The elongate protrusion 59 and tab 61 are separated by the third channel 55,
with the tab 61 being offset from the third channel 55, as best shown in
figures 7
and 8.
Referring to figure 15, the locking mechanism 71 comprises two pins 73 (only
one
shown), each being adapted to be received through aperture 57a in the upper
wall
49 of the tooth 41, and into the enclosure 91 during assembly.
Each pin 73 comprises a metal retaining clip 75 providing a projection 77. The
retaining clip 75 is bonded to a resiliently flexibly material 79, such as
polyurethane.
The resiliently flexible material 79 is received in a recess 81 of a metal
housing
83.
When the pin 73 is assembled, the projection 77 extends beyond the boundary of
the housing 83 when the pin 73 is in its normal condition.
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In use, the adaptor 21 is secured to a component of the earthmoving equipment,
such as a bucket, not shown. The adaptor 21 is typically welded to the bucket.
The adaptor 21 is protected from substantial wear by the tooth 41, which is
replaced as the tooth becomes worn or damage. As this is quite regular it is
important to have a tooth 41 which may easily and quickly be removed from the
adaptor 21.
Referring to figures 16 to 19, when assembling the tooth 41 to the adaptor 21,
the
socket 43 of the tooth 41 receives the nose 27 of the adaptor 21 such that the
tab
61 and elongate protrusion 59 align with, and are siidingly received in the
first
channel 37 of the nose 27. The tooth 41 continues to slide along the nose 27
until
the internal surfaces of the upper wall 49 and bottom wall 51 of the socket 43
engage the upper surface 31 and lower surface 33 of the nose 27 respectively,
at
which point the third channel 55 aligns with the second channel 39 to provide
an
enclosure 91.
Due to the offset of the tab 61 from the third channel 55, when the tooth 41
is
received on the adaptor 21, a portion of the first channel 37 provides a
recess 93
between the second channel 39 and the tab 61, for reasons which are detailed
below.
In order to lock the tooth 41 to the adaptor 21, each pin 73 is placed in the
enclosure 91 to be releasably retained therein. Each pin 73 is inserted
through
each aperture 57a and passes through the wider portion 41 of the second
channel
39 until the projection 77 of the pin 73 engages the ramp 40, as shown in
figure
17.
In order to move past the ramp 40 a relatively small force is applied to the
pin 73.
The ramp 40 forces the projection 77 inwardly with respect to the housing 83,
allowing the pin 73 to move further along the enclosure 91.
As the projection 77 passes over the ramp, 40, the projection 77 aligns with
the
recess 93 and is urged outwardly by the resilient nature of the flexible
material 79
until the projection 77 is received in the recess 93, as best shown in figure
18. In
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this position the rear surface 85 of each pin 73 engages a wall 38a of the
second
channel 39, whilst adjacent portions 78 of the projection 77 engage an opposed
wall 38b to wall 38a, maintaining the tooth 41 in good fitment relative to the
adaptor 21.
When each pin 73 is in position, the bottom and top of the pin 73 do not
protrude
beyond the upper and lower peripheries of the tooth 41, as best shown in
figure
18.
When disassembling the tooth from the adaptor, each pin 73 must first be
removed. In order to do so, a tool (not shown) is inserted into the apertures
57a
in the upper wall 49. A relatively small force is then applied to the pin 73
to force
the projection 77 inwardly to allow the pin to pass through apertures 57b in
the
bottom wall 51 of the tooth 41.
Figures 20 to 23 show a tooth 141 according to a second embodiment. Like
numbering is used on similar components as was used for describing the tooth
according to the first embodiment. In this embodiment, the configuration of
the
locking mechanism 71 and adaptor 21 remain the same as was described in the
first embodiment.
Similarly to the first embodiment, the tooth 141 of the second embodiment has
two apertures 57 through the upper wall 49. Each aperture 57 is in alignment
with
the respective third channel 55 on each sidewall 53.
The bottom wall 51 also has two apertures 58. These apertures 58 are smaller
in
size than the two apertures 57 of the upper wall 49, and are of suitable size
such
that the locking mechanism 71 is prevented from passing therethrough.
When each pin 73 is in position, the bottom of the pin 73 engages or is
adjacent
the bottom wall 51 of the tooth 41, whilst the top of the pin 73 is adjacent
or
substantially flush with the outer surface of the upper wall 49 of the tooth
41, as
best shown in figure 23.
CA 02576218 2007-02-02
WO 2006/012689 PCT/AU2005/001154
-20-
When disassembling the tooth 141 from the adaptor 21 each pin 73 must first be
removed. In order to do so, a tool (not shown) is inserted into the apertures
58 in
the bottom wall 51. A relatively small force is then applied to the pin 73 to
force
the projection 77 inwardly as it passes over the ramp 40. Once each pin 73 is
removed, the tooth 141 may easily be removed from the adaptor 21.
The configuration of the present invention protect the pin 73 from the
environment
and ensures the pins 73 are not knocked out or damaged during service. Due to
this configuration, the fit of the pins 73 relative to the tooth and adaptor
need not
be as robust as if the pins 73 were exposed. Hence the forces required to
insert
and remove the pins are relatively small when compared to those of other
available systems.
Throughout the specification, unless the context requires otherwise, the word
"comprise" or variations such as "comprises" or "comprising", will be
understood to
imply the inclusion of a stated integer or group of integers but not the
exclusion of
any other integer or group of integers.
