Note: Descriptions are shown in the official language in which they were submitted.
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Description
Coupling Apparatus
Technical Field
This invention relates to a coupling apparatus
and more particularly to a coupling apparatus that is
utilized to quickly couple and uncouple a variety of
work implements to the support arm of a vehicle.
Background Art
In the operation of an earthmoving vehicle
such as an excavator, it is a common occurrence to
encounter different types of materials and digging
conditions. As a result, specialized buckets have been
designed to be utilized in a specifi type of soil or
for a specific type of digging operation. Therefore it
is not uncommon for an operator of an excavator to
switch from one bucket to another to perform a variety
of operations.
The excavator bucket linkage commonly includes
a support arm or stick, and a bucket rotation linkage
that is mounted to the stick. The bucket is mounted at
one point to the stick and at another point to the
rotation linkage. A pair of pivot pin assemblies are
positioned within aligned bores formed between the
bucket and excavator linkage at each mounting point.The
pin assemblies are mounted within their respective
bores with an interEerence fit or press fit. ~emoval
and replacement of the pin assemblies requires a good
deal of time and specialized equipment in most
instances. Therefore frequent changes between work
implements can be very costly in terms of machine down
time. On the other hand, if an implement is not
changed because of the time required to do so, the work
efficiency of the machine is sacrificed.
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To alleviate the aforementioned problem,
quick-disconnect mountings oE various types have been
developed. While many of the current designs function
to quickly connect and disconnect the various types of
implements to an excavator linkage, their construction
has created a compromise in the work efficiency of the
implement. In some instances, as in U.S. Patent
4,187,050 issued on February 5, 1980 to Gail G. Barbee
and assigned to the assignee of the subject
application, an adapting bracket is connected to the
excavator linkage where a conventional implement such
as a bucket would normally be attached. The bracket is
provided with a connecting arrangement that engages a
number of work implements that have been specifically
designed for attachment to the bracket. This results
in an alteration in the geometry of the excavator
linkage. Since the bucket is no longer connected
directly to the stick, its point of rotation, or
tipping radius, about its connection to the mounting
bracket is offset from that of a conventional bucket.
The geometry of the bucket linkage is specifically
calculated to apply the optimum force available from an
actuating cylinder to the tip of the bucket where the
teeth will penetrate the earth. Movement of the point
of bucket rotation upsets this condition and the amount
of digging force applied to the bucket is greatly
reduced.
Other so-called "quick couplingn devices
require the use o~` a bracket assembly that have a pair
of upstanding sidewalls that extend between the end of
the stick and the bucket rotation linkage. Pivot pins
extend through bores in the end of the stick and
rotation linkage to mount the bracket assembly
thereto. The pivot pins or other bearing structure
such as a boss, extends from the outer surface of the
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sidewalls of the bracket to engage appropriately
contoured hinge plates of a bucket. Since the load
bearing structure is cantilevered Erom the sidewalls of
the bracket, the forces are not directly transferred
from the hinge plates of the work implement to the
sidewalls of the bracket. Because the sidewalls of the
bracket assembly serve only as support for the load
bearing structure, very substantial structural members
must be positioned laterally between the sidewalls to
strengthen the bracket assemb]y. The laterally
extending structure also provides support for a locking
device that is centrally disposed between the
sidewalls. The locking device is needed to secure the
bucket to the bracket assembly. Since the locking
device is offset from the connection between the pivot
bracket and the bucket, the forces created during a
digging operation are amplified as they are transferred
from the pivot pins, through the bracket structure and
to the locking device. This requires the locking
device, as well as the lateral structural members, to
be of very substantial size and weight to accommodate
such severe loading. As a result, the entire weight of
the bracket assembly and attached bucket is far greater
than that of a conventional bucket. The additional
weight works as a great disadvantage to the operation
of a vehicle. Each pound of additional weight reduces
the capacity of the bucket by a pound. Also, for each
additional pound at the bucket, an additional two
pounds must be added to the counterweight at the
opposite end of the vehicle. Two designs of this type
are disclosed in U.S. Patent 3,556,323 issued on
January 19, 1971 to Damian M. Hermmermann and U.S.
Patent 4,214,840 issued on July 29, 1980 to John H.
Beales.
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The present invention is directed to
overcoming one or more of the problems as set forth
above.
Disclosure of the Invention
In one aspect of the invention a coupling
apparatus for use between a pair of support arms
having distal ends and a work implement is disclosed.
A pair of hinge plates are mounted on the work
implement and each defines a first and second
contoured receptacle that are spaced from one another.
A pair of connecting links having a generally uniform
length and width and first and second end portions
pivotally connected between said distal ends of said
support arms are configured for nesting engagement
within the first and second receptacles respectively.
A guide plate is secured to each hinge plate at a
location that is adjacent one of said first and second
receptacles to guide the first end portion of said
2~ connecting links into engagement with one of said
receptacles and to limit the axial movement of the
connecting links with respect to the hinge plates upon
completion of said engagement. A locking means is
associated with the connecting links for selectively
locking the end portions into engagement with said
receptacles with substantially the entire length and
width of each connecting link in direct, linear force
transmitting relation therewith. A first pin member
extends between the first end portions of the
respective connecting links to pivotally mount said
connecting links to one of said support arms and a
second pin member extends between the second end
portions of the connecting links to pivotally mount
the connecting links to the other of said support
arms, said first and second pin members being the only
structural connection between said connecting links.
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In another aspect of the invention a vehicle
having a support arm, a bucket defining a pair of
hinge plates that extend from said bucket in spaced
relation to each other, and a linkage arrangement
associated with said support arm and said bucket to
provide rotation of said buc]cet with respect to the
support arm is provided with an apparatus for rapidly
coupling and uncoupling said bucket and the support
arm. The coupling apparatus comprises a first
receptacle having a preselect:ed contour that is formed
in each of the hinge plates. A second receptacle
having a preselect~d contour is also formed in each of
the hinges plates and is spaced from the first
receptacle. A pair of connecting links having a first
end portion having a configuration sufficient for nest
engagement with the first receptacle, and a second end
portion having a configuration sufficient for nesting
engagement with the second receptacle is also
provided. Means for selectably locking the engagement
of the first and second end portions of the connecting
links with the first and second receptacles is also
included. A means for pivotally mounting the first
end portions of the connecting links to the support
arm and the second end portion of the connecting links
to the linkage arrangement is included, said means
being the only structure extending between the
connecting links. A guide plate is secured to each
hinge plate at a location that is adjacent one of said
first and second receptacles to guide the connecting
3~ links into engagement with the first and second
receptacles and to limit the axial movement of the
connecting links with respect to the hinge plates upon
completion of said engagement.
~2S~15;19
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In another aspect of the present invention a
coupling apparatus is provided for use between a pair
of support arms having distal ends and a work
implement. The coupling apparatus includes a pair of
hinge plates mounted on the work implement each of
which defines a pair of contoured receptacles that are
spaced from one another. A pair of connecting links
having first and second end portions are pivotally
connected between said distal ends of said support
arms and are configured for nesting engagement within
the receptaclesO A flange member having an angled
surface defined thereon is mounted to each of said
hinge plates. A wedge member having an angled surface
defined thereon and an elongated slot formed
therethrough is provided along with a fastening means
that is positioned within the elongated slot to secure
the wedge member to each of the connecting links for
selective movement of the angled surface of the wedge
member into and out of engagement with the angled
surface of the flange member.
In another aspect of the present invention a
coupling apparatus is provided for releasably mounting
a bucket member to a compound linkage arrangement that
2~ includes a stick member and a bucket rotation linkage
that is intended for use with a backhoeing excavator.
The coupling apparatus includes a pair of hinge plates
each of which have a pair of spaced receptacles
opening therefrom that are mounted on the bucket
member in a substantially rigid, non-deformable
relationship. A pair of connecting links is provided
for directly pivotally connecting said stick member
and said bucket rotation linkage to said hinge plates
said connecting links having a first and second end
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portion that is positionable to engage one oE the
respective hinge plates with substantially the entire
width of each end portion in direct, linear force
transmitting engagement with one of the respective
pairs of receptacles. A locking means is included for
selectively locking the connecting links into
engagement with the respective receptacles.
In still another aspect of the present
invention a coupling apparat1ls is provided for
releasably mounting a bucket member to a compound
linkage arrangement. The coupling apparatus includes
a pair of hinge plates adapted to be mounted on the
bucket member in substantially rigid, non-deformable
relationship therewith. A means for directly
pivotally connecting said compound linkage arrangement
to said hinge plates is also provided. The connecting
means includes a pair of connecting links, each link
having a first and second end portion which is
positionable to engage one of the respective hinge
plates with their end portions aligned in direct,
linear force transmitting engagement therewith. First
and second pin members extend laterally between the
respective first and second end portions of the
connecting links to pivotally mount the connecting
links to the respective bucket and compound Iinkage
arrangement. The pin members are the sole
interconnection between said connecting links. ~n
engaging means simultaneously engages each connecting
link and its corresponding hinge plate to lock them
together. The engaging means is positioned in linear
relation to both the connecting link and the hinge
plate so that forces passing through the engaging
means are transmitted along a substantially linear
path.
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A coupling apparatus as set forth above
allows the operator of a vehicle to change from one
work implement to another in a very short period of
time. The connecting links engage the bucket at the
same location that a conventional bucket would be
pinned to the bucket linkage. Therefore, there is no
alteration in the geometry of the bucket linkage from
that of a conventional bucket:, thus the optimum
digging force is available to all of the various work
implements. Also, since there is no lateral structure
interposed between the connecting links, aside from
the pivot pins that connect the respective end
portions to the excavator linkage~ the weight of the
coupling apparatus is very little more than that of a
conventionally mounted work implement of the same
type. Further, since each connecting link is secured
directly to each o~ the respective hinge plates, the
working forces are directly transferred, in-line, from
on~ component to the other for more effective
distribution. Therefore
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it can be seen that a coupling apparatus is provided
that provides the capability of interchanging a
plurality of work implements in a ~uick and simple
manner without sacrificing the function of each work
implement.
Brief Description of the Drawings
Fig. 1 is a partially sectioned side view of
an excavator bucket having a coupling apparatus that
embodies the principles of the present invention;
Fig. 2 is a partial top view oE the coupling
apparatus as viewed along lines II-II in Fig. l;
Fig. 3 is a side view of the coupling
apparatus partially engaged with a bucket that is shown
with portions thereof broken away;
Fig. 4 is an enlarged, partially sectioned
side view of an alternate embodiment of a locking
apparatus;
Fig. 5 is an end view of the alternate locking
apparatus as viewed along lines V-V of Fig. 4; and
Fig. 6 is a top view of the alternate locking
apparatus as viewed along line VI-VI on Fig. 5.
Best Mode for Carrying Out the Invention
Referring to the drawings and more
particularly to Fig. 1, a coupling apparatus 10 is
shown that is utilized to attach a work implement 12,
such as an excavator bucket, to a vehicle (not shown).
The vehicle, in this instance, is an excavator or
backhoe that utilizes a compound linkage arrangement to
manipulate and load the bucket in a well known manner.
The linkage includes a support arm 14 which is commonly
referred to as a "stick", to which the bucket is
attached in a manner to be described hereinafter.
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The linkage includes a pair of connecting
links 16 that are positioned on opposite sides of a
distal end 18 of the stick 14. The connecting links 16
are generally of uniform thickness and are
boomerang-shaped to form a concave portion 20 and
terminate at first and second end portions 22 and 24.
The first end portion 22 is contoured so as to form a
generally round profile 26. The second end portion 24
also has a round profile 28 formed thereon. Each end
portion 22 and 24 deEines a bore 30 and 32,
respectively, and the bores 30 in the first end portion
22 are aligned with a bore that extends through the end
18 of the stick 14. As shown in Figs. 1 and 3, a first
pin member 36 is positioned in the aligned bores of the
connecting links and the stick to rotatably mount the
first end portions 22 of the connecting links 16 to the
stick 14. A retaining assembly 35 has a first portion
36 that engages one end of the first pin member 34 to
prevent relative rotation thereof with respect to the
connecting links 16. A second portion 38 of the
retaining assembly 35 engages the opposite end of the
first pin member and prevents axial movement of the pin
34 with respect to the connecting links 16.
A rotating means 40 is also associated with
the excavator linkage to provide movement of the
connecting links 16 about the first pin member 360 The
rotation means 40 includes a pair of idler links 42 and
a secondary support arm or power link 44 that extend
respectively from and are connected to the stick 14 and
the connecting links 16. The idler links 42 have a
first end portion 46 rotatably mounted to the stick 14
and the power link 44 has a first end portion 48 tFigs.
2 and 3) rotatably mounted to the second end portions
24 of the connecting links 16. The bores 32 of the
second end portions 24 oE the connecting links 16 are
'12599~
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aligned with a bore 50 that extends through the first
end portion 48 of the power link 44. A second pin
member 52~ identical to the first pin member, is !
po~itioned within the aligned bores 32 and 50 to allow
relative rotation between the connecting links and the
power link. A second retaining assembly 53 has a Eirst
and second portion 54 and 55 (Fig. 2) that acts
identically to the retaining assembly 38 to secure the
second pin member 52 to the connecting links 16. The
power link 44 has a second end portion 56 that is
rotatably connected to a second end portion 58 of each
of the idler links 42. A hydraulic actuator, or
cylinder (not shown) has a first end portion 62, in
this instance the rod end, that is also connected to
the second end portions 56 and 58 of the respective
idler and power links 42 and 44. A second end of the
cylinder (not shown) is mounted to the stick 14 and
upon actuation of the cylinder, causes movement of the
rotation means 40 with respect to the stick 14 to pivot
the connecting links 16 about the first pin member 34.
The bucket 12 is provided with a pair of
mounting plates or hinge plates 64 that are laterally
spaced from each other across an upper portion 66 of
the bucket 12 and are secured thereto as by welding or
other suitable means. First and second receptacles 68
and 70 are formed in each of the hinge plates 64. The
first receptacle 68 is substantially semi-circular and
is open in a generally rearwardly facing direction, or
leftwardly facing as viewed in Figs. 1 and 3, with
respect to the bucket. The second receptacle 70 is
spaced rearwardly from the first receptacle 68 and is
configured so as to form a portion of a circle that is
greater than 90 degrees but less than 180 degrees. The
second receptacle 70 opens generally towards the first
receptacle 68. A reinforcement beam 72 having a
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generally triangular configuration extends laterally
across the bucket 12 between the hinge plates 64 and
deEines a convex protrusion 74 that is positioned
between the first and second receptacles. Being so
configured, the first receptacles 68 act as a socket to
receive the rounded profile 26 formed by the first end
portions 22 of the connecting links 16. Likewise, the
second receptacle 70 receives the portion of the
rounded profile 28 formed by the second end portions 24
oE the connecting links 16. When the end portions 22
and 24 of the connecting links 16 are engaged with the
receptacles 68 and 70, the axial positioning of the
connecting links is maintained by a plurality of guide
plates 76. The guide plates 76 are secured to an outer
surface 78 of the hinge plates 64 and are positioned to
cover the outer sides of each receptacle. Each guide
plate 76 has a flared portion 80 that extends outwardly
from the hinge plates and serves to guide the
connecting links into engagement with the receptacles.
The engagement between the end portions 22 and
24 of the connecting links 16 and the respective
receptacles 68 and 70 is maintained by a locking means
82 that is associated with each of the connecting links
and is shown best in Figs. 1 and 2. Each locking means
includes a hook-shaped flange 84 that extends upwardly
from each of the hinge plates 64. The flange 84 has an
angled portion 86 formed on a forwardly directed face
88 extending to the right as viewed in Eiys. 1 and 3.
A block-shaped wedge member 90 is positioned
on an upper surface 92 of the second end portions 24 of
each connecting link 16 in opposing and closely
adjacent relation to the angled portion 86 of the
flange 84 when the end portions 22 and 24 of the
connecting links 16 are nested within the respective
receptacles 68 and 70. Each wedge member 90 is secured
to the upper surface 92 of the connecting linlcs 16 by a
pair of threaded fasteners such as bolts 94. The bolts
94 are positioned in spaced relation to each other in a
vertically oriented, oblong slot 96 defined in the
wedge member 90. The length oE the slot 96 is greater
than the spacing between the bolts 94 and thereby
allows the movement of the wedge member 90 beyond a
rearward edge 98 of the connecting links 16 toward the
flange 84. The wedge member 90 also has a pair of
angled portions 100 and 101 formed on each end
thereof. The wedge member is positioned with the
angled portion 100 facing the angled portion 86 of the
flange member 84. A lug 102 extends from an outer side
104 of the wedge members 90 and may be utilized, along
with angled portion 101, to assist the movement of the
wedge members into or out of engagement with the flange
member 84.
Turning now to Figs. 4-6, an alternate locking
means 82' is disclosed. A pair of locking means 82' is
provided, one for each connecting link, and since they
are identical~ only- one will be described hereinafter.
Components in the alternate embodiment that are
identical to those previously described will be
indicated by the same reference numerals. The locking
25 means 82' includes a cylindrical member 106 that
defines a bore 108 that extends the entire length of
the cylindrical member 106. The cylindrical member is
secured to an outer surface 110 of each connecting link
16. An angled surface 112 is defined on a forward or
rightward end of the cylindrical member as viewed in
Fig. 4. A pin assembly 114 having a round body portion
116 is disposed within the bore 108 of the cylindrical
member 106 and has a first end 118 that defines a
relieved portion 120 along its circumference. A handle
35 or lever 122 is secured to a second or rearward end 124
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of the pin body 116 and extends from the pin body in a
direction normal thereto and is positioned adjacent the
angled surface 112 of the cylindrical member 106. The
lever 122 is retained in its position adjacent the
angled surface by a closure e]ement 126. The closure
element 126 forms a second angled surface 128 that
extends parallel to the anglecl surEace 112 of the
cylindrical member 106 and is spaced therefrom to form
a slot or track 130 in which the lever 122 may
traverse. The closure element 126 includes two
horizontally extending plates 132 and 134 that are
respectively secured to an upper and lower portion 136
and 138 of the cylindrical member 106 in parallel
relation to each other. A semi-circular rod member 140
is secured to each of the plates 132 and 134 and
extends therebetween at an angle to form the second
angled surface 128 as previously discussed. A
generally "L~ shaped retainer plate 142 is secured to
each of the horizontal plates 132 and 134. A threaded
fastener 144, such as a bolt, extends through one end
146 of the retainer plate 142 to secure the end 146 to
each of the plates 132 and 134. Only one threaded
fastener 144 is used to mount the retainer plates so as
to allow the retainer plate to pivot about the
fastener. As shown in Fig. 6, the retainer plate 142
may be pivoted toward and away from a position wherein
a leg 148 of the retainer plate extends across the slot
130 to block the movement of the lever 122 along the
slot. A protrusion 150 is formed on the leg 148 of the
retainer plate and it extends toward the respective
plates 132 and 134. A notch 152 is formed in each of
the plates 132 and 134 and receives the protrusion 150
and serves as a catch to selectively hold the position
of the retainer plates when they are positioned across
the slot 130.
ll -
A pin receiving member 154 is connected to
each of the hinge plates 64 at a location that is
closely adjacent to the first end portion 118 oE the
pin assembly 114. The pin receiving member 154
includes a bifurcated base member 156 that forms a pair
of uprights 158. A cap 160 spans the uprights 158 and
is secured thereto by threaded fasteners 162. The cap
and the uprights form a socket 164 that is sized to
receive the first end 118 of the pin assembly 114 in
load bearing engagement with a lower surface 166 of the
cap 160. A plurality of shims 168 may be utilized to
adjust the height of the cap with respect to the
uprights and the first end 118 of the pin assemby 114
to achieve a proper load bearing relationship between
the pin and the cap.
Industrial Applicability
When attaching a bucket or other work
implement 12 to a vehicle such as an excavator, the
support arm 14 is manipulated to bring the first end
portions 22 of the connecting links 16 into engagement
with the first receptacles 68, as shown in Fig. 3.
This is accomplished with the aid of the guide plates
76 which help to axially "steer" the movement of the
connecting links as they approach engagement with the
receptacles. After the first end portions 22 of the
connecting links are seated, the hydraulic cylinder of
the rotating means 40 is actuated to rotate the second
end portions 24 of the connecting links 16 into
engagement with the second receptacles 70. When the
connecting links are properly seated, the wedge members
90 which have been held in a position forward of the
rear edge 98 of the connecting links 16 are moved
rearwardly toward the flanges 84 formed on the hinge
plates 64. This movement may be accomplished by
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striking the angled portion 10] or the lugs 102 of the
wedge mernbers 90 with a hammer or similar tool. As the
wedge members 90 are moved toward the flanges 84, the
angled portion 100 of the wedge members 90 engages the
angled portion 86 of the flanges in face-to-face
relation. Under the urging of the hammer, the angled
portions 100 and 86 are forced into tighter engagement
with each other and thus the connecting links are urged
into tighter seating within the respective receptacles
68 and 70. When a tight engagement is achieved, the
bolts 94 may be tiyhtened to hold the wedge member 90
in position.
When detaching the bucket 12 from the
excavator, the process is basically reversed. The
bolts 94 are loosened, the wedge members 90 are moved
forwardly with the aid of a hammer striking the lugs
102, and the excavator linkage is manipulated to remove
the connecting links 16 from engagement with the
receptacles 68 and 70 in the hinge plates 64. It may
be seen that as this procedure is performed frequently
over a period of time, that substantial wear may occur
between the components. This wear is accommodated by
the face-to-face engagement of the respective angled
portions 86 and 100 of the flange 84 and the locking
means 82.
Turning now to Figs. 4-6, the operation of the
alternate embodiment oE the locking means 82' will ke
described. The initial operation of the excavator
linkage is identical to that previously set forth, when
bringing the connecting links 16 into engagement with
the receptacles 68 and 70 of the hinge plates 64. Once
the connecting links are properly seated, the lever 122
of the pin assembly 114 may be freed from its "storedn
position. This is accomplished by moving the retainer
plates 142 vertically away from the respective upper
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and lower plates 132 and 134 until the protrusions 150
of the retainer plates 142 clear the slots 152 in the
upper plates and lower plates 132 and 134. Having done
that, the retainer plates 142 may be rotated about
their mounting bolts 144 to a position that does not
obstruct the slots 130 as shown in phantom lines in
Yig. 6. ThereaEter the levers 122 of the individual
pin assembly 114 may then be grasped by the operator
and moved downwardly in their respective slot 130.
Since the slot is angled, the first (or rearward) end
118 of the pin body 118 is moved toward the pin
receiving member 154. It should be noted that during
the initial movement of the lever, the first end
portion 118 of the pin body 116 enters the socket 164
formed in the pin receiving member 1540 The relieved
portion 120 formed on the first end portion 118 is
positioned on the circumference in a manner that allows
a space between the pin body 116 and the lower surface
166 of the cap 160 as the pin body enters the socket.
As movement of the pin body continues, the relieved
portion is rotated away from its initial orientation
with the lower surface 166 of the cap, and the space
therebetween is reduced as the lever 122 is lowered.
When the lever has traversed the entire length of the
slot 130 to a position shown in phantom lines in Fig.
4, the pin body 116 has been entirely advanced and
rotated to a position wherein it is in load bearing
contact with the lower surface 166 of the cap member.
Upon the completion of pin engagement, the retainer
plates 142 may again be rotated back to their stored
position. The retainer plates 142 will be positioned
across the slot 13 and will cooperate with the lower
plate 134 to hold the handle against upward movement in
the slot 130. Release of the pin may occur by
3S reversing the above procedure. When disengaged, the
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position of the lever 122 is held against downward
movement in the slot 130 by the retainer plate 142 that
is associated with upper plate 132. As previously
discussed, the height of the cap 160 with respect to
the uprights 158 may be adjusted with the use of shims
168. The height may be set originally to compensate
for any manufacturing tolerances that may vary the
proper distance from bucket to bucket. The height may
also be adjusted later to compensate for wear. Also,
the relieved portion 120 on thle pin body 116
compensates for any dirt build-up that may occur during
operation and greatly eases the seating of the pin.
With a coupling apparatus 10 as disclosed, a
bucket may be mounted to the linkage arrangement of the
vehicle at the same points of attachment as that of a
conventional bucket. This is mainly due to the
configuration of the connecting links 16. Since the
connecting links are provided with the concave portion
20 they are able to nest very closely about the convex
portion 74 of the reinforcement beam 72. By doing so,
the distance between the teeth of the bucket and the
first pin member 34 about which the bucket rotates,
remains the same as that of a conventional bucket.
This distance is commonly referred to as the tip
radius, and since it remains unchanged, the optimum use
oE the available digging force that is provided by the
hydraulic cylinder also remains unchanged. Another
advantage resides in the absence of reinforcing
structure extending laterally between the connecting
links 16. The entire widths of the contoured first and
second end portions 22 and 24 are in load bearing
engagement with their respective receptacles 68 and
70. This allows the direct, in-line transmission oE
digging forces from the hinge plates 64 to the
connecting links 16 and vice versa, thus allowing the
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elimination of the reinforcing structure. The only
members that extend between the connecting links are
the first and second pin members 34 and 52 which serve
mainly as pivot mountings and not structural support.
This permits the normal operation of the bucket
rotating means 40 without having to conmpensate for any
interference with from additional structure. Also,
since there is very little structure added to that of a
conventional bucket, the weight increase and the
resulting loss of bucket capacity is minimal.
Other aspects, objects and advantages of this
invention can be obtained from a study of the drawings,
the disclosure and the appended claims.
