U.S. patent number 3,608,930 [Application Number 04/859,755] was granted by the patent office on 1971-09-28 for hydraulic clamping apparatus for a side-shiftable mechanical digger.
This patent grant is currently assigned to Deere & Company. Invention is credited to Yves Loranchet, Pierre Moriceau.
United States Patent |
3,608,930 |
Moriceau , et al. |
September 28, 1971 |
**Please see images for:
( Certificate of Correction ) ** |
HYDRAULIC CLAMPING APPARATUS FOR A SIDE-SHIFTABLE MECHANICAL
DIGGER
Abstract
A mechanical digger support assembly has a boom-supporting slide
frame mounted for transverse sliding on a tractor-supported,
transverse main frame and hydraulically applied clamping apparatus
are provided for securing the slide frame against movement at
selected positions along the main frame.
Inventors: |
Moriceau; Pierre (Saran,
FR), Loranchet; Yves (Le Saumon, FR) |
Assignee: |
Deere & Company (Moline,
IL)
|
Family
ID: |
9032396 |
Appl.
No.: |
04/859,755 |
Filed: |
September 22, 1969 |
Foreign Application Priority Data
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Apr 15, 1969 [FR] |
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6911555 |
|
Current U.S.
Class: |
280/456.1;
414/695; 172/274; 37/379 |
Current CPC
Class: |
E02F
3/386 (20130101) |
Current International
Class: |
E02F
3/38 (20060101); E02F 3/36 (20060101); B60d
001/00 () |
Field of
Search: |
;280/456 ;172/274
;37/103 ;214/138 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
975,029 |
|
Nov 1964 |
|
GB |
|
1,169,734 |
|
Sep 1968 |
|
FR |
|
1,330,860 |
|
May 1963 |
|
FR |
|
Primary Examiner: Friaglia; Leo
Claims
We claim:
1. In a mechanical digger including a mobile vehicle, a transverse
main frame supported on the vehicle and having guide means
extending transversely therealong and a slide frame mounted for
movement along said guide means, the improvement comprising: said
guide means including first and second transverse surface means at
the upper forward and lower rear portions of said main frame, said
slide frame including first and second complementary surface means
respectively positioned for abutting engagement with said first and
second transverse surface means upon moving said slide frame to a
clamped position located upwardly and rearwardly relative to said
main frame and releasable clamping means mounted between said slide
frame and guide means and oriented for moving said slide frame to
said clamped position.
2. The invention defined in claim 1 wherein said clamping means is
oriented for moving the slide frame upwardly and rearwardly at an
angle of approximately 45.degree..
3. The invention defined in claim 2 wherein the clamping means
includes a clamping block having an angular recess at one end and
said guide means includes a complementary angular part received in
said recess.
4. The invention defined in claim 3 wherein the recess is right
angular.
5. The invention defined in claim 4 wherein the clamping means
includes hydraulic loading means.
6. The invention defined in claim 5 wherein the hydraulic loading
means includes a hydraulic piston having one end positioned for
applying a bearing force to said clamping block.
7. The invention defined in claim 6 wherein the clamping block and
hydraulic piston are mounted for relative crosswise movement.
8. The invention defined in claim 1 wherein said first and second
surface means of said guide means respectively include a transverse
rail at the upper forward portion of the main frame and a
transverse groove in the lower rear portion of the main frame and
said first and second complementary surfaces of said slide frame
respectively including a recess receiving said rail and a
projection received in said groove.
9. The invention defined in claim 8 wherein said groove opens
rearwardly and has a lip at its entrance and said projection has a
portion extending into said groove and over said lip, the lip
acting to retain the projection within the groove.
10. The invention defined in claim 9 wherein the projection is
removably fastened to the slide frame whereby it may be easily
disposed within the groove when assembling the main and slide
frames together.
11. The invention defined in claim 9, wherein said groove and lower
projection have complementary upper surfaces inclined upwardly and
rearwardly at approximately 45.degree. to the horizontal and the
lip has a vertical front surface.
12. The invention defined in claim 8 wherein said groove opens
downwardly and the projection is hooklike and projects upwardly
into the groove.
13. The invention defined in claim 12 wherein said main frame and
slide frame have complementary, vertical bearing pads at their
respective lower rear and lower front portions and wherein said
groove has a vertical front surface and a downwardly and rearwardly
inclined top surface which intersects the vertical surface and main
frame bearing pad to form an N-shape in cross section and wherein
the hooklike projection has complementary vertical front and
downwardly and rearwardly inclined top surfaces.
14. The invention defined in claim 13 wherein the respective bottom
and top surfaces of the groove and projection define an included
angle of approximately 45.degree. with the respective vertical
surfaces.
15. The invention defined in claim 8 wherein the rail is generally
rectangular in cross section and the recess is shaped complementary
to said rail.
16. The invention defined in claim 15 wherein said groove opens
rearwardly and has a lip at its entrance and said projection has a
portion extending into said groove and over said lip, the lip
acting to retain the projection within the groove.
17. The invention defined in claim 16 wherein the projection is
removably fastened to the slide frame whereby it may be easily
disposed within the groove when assembling the main and slide
frames together.
18. The invention defined in claim 17 wherein said groove and lower
projection have complementary upper surfaces inclined upwardly and
rearwardly at approximately 45.degree. to the horizontal and the
lip has a vertical front surface.
19. The invention defined in claim 15 wherein said groove opens
downwardly and the projection is hooklike and projects upwardly
into the groove.
20. The invention defined in claim 19 wherein said main frame and
slide frame have complementary, vertical bearing pads at their
respective lower rear and lower front portions and wherein said
groove has a vertical front surface and a downwardly and rearwardly
inclined top surface which intersects the vertical surface and main
frame bearing pad to form an N-shape in cross section and wherein
the hooklike projection has complementary vertical front and
downwardly and rearwardly inclined top surfaces.
21. The invention defined in claim 20 wherein the respective bottom
and top surfaces of the groove and projection define an included
angle of approximately 45.degree. with the respective vertical
surfaces.
22. In a mechanical digger including a mobile vehicle, a transverse
main frame supported on the vehicle and having guide means
extending transversely therealong and a slide frame mounted for
movement along said guide means, the improvement comprising:
releasable clamping means for selectively clamping the slide frame
to said main frame including a hydraulic cylinder and piston
carried by said slide frame, said piston being positioned for axial
movement towards and crosswise to said transverse main frame, a
clamping block carried by said slide frame having one side in
engagement with said guide means and the opposite side in axial
alignment with said piston and a bearing plate being positioned
between said clamping block and piston whereby pressurized
extension of said piston will result in a force being applied to
said clamping block to force it into clamping engagement with said
guide means.
23. The invention defined in claim 22 wherein the force-applying
end of said piston is spherical and wherein the mounting of the
clamping block and bearing plate permits the piston to move
crosswise relative to the clamping block and bearing plate.
24. The invention defined in claim 23 wherein the hydraulic piston
and cylinder is oriented at an acute angle with reference to the
horizontal.
25. The invention defined in claim 24 wherein said acute angle is
approximately 45.degree..
26. The invention defined in claim 24 wherein the clamping block
has an angular recess at said one side and said guide means
includes a complementary angular part received in said recess.
27. The invention defined in claim 26 wherein the recess is right
angular.
28. In a mechanical digger including a mobile vehicle, a transverse
main frame supported on the vehicle and having guide means
extending transversely therealong, and a slide frame mounted for
movement along said guide means, the improvement comprising:
releasable clamping means for selectively clamping the slide frame
to said main frame including at least one hydraulically loadable
piston carried by said slide frame, control valve means for
selectively connecting said piston to a source of fluid pressure or
to a fluid return including a valve bore intersected by axially
spaced supply and exhaust bores and having an inlet for connection
to a source of fluid pressure, said supply and exhaust bores being
respectively in fluid communication with said piston and return, a
first valve seat and check valve in said valve bore between said
inlet and supply bores and a second valve seat and check valve in
said valve bore between said supply and exhaust bore, bias means
urging said first and second check valves against the first and
second valve seats for preventing flow between the inlet and supply
bores and the supply and exhaust bores, respectively, said bias
means having a force lesser than the inlet pressure whereby the
first check valve will be unseated when subjected to inlet pressure
and means for simultaneously unseating said second check valve and
seating said first check valves whereby clamping fluid pressure is
exhausted from the piston.
29. The invention defined in claim 28 wherein the last-mentioned
means includes a pair of pistonlike members having opposed stems
and having head ends positioned against said first and second check
valves, said bias means including a coilspring disposed about said
stems and urging said pistonlike members oppositely, a check valve
unseating member positioned for engagement with that side of the
second check valve opposite said second pistonlike member, a
plunger axially shiftable in said bore and being operatively
associated with said valve unseating member for selectively
shifting it to unseat said second check valve and lever means
operatively associated with said plunger for selectively shifting
it axially toward said valve unseating member.
30. The invention defined in claim 29 wherein a coil spring having
a stiffness greater than the inlet pressure is positioned with
opposite ends in bearing relationship with the valve unseating
member and said plunger.
31. The invention defined in claim 30 wherein the lever means
includes a pivoted lever having a cam surface positioned so as to
contact and move the plunger axially after a predetermined rotation
of the lever.
32. The invention defined in claim 28 and further including a bore
joining said supply and exhaust bores and a relief valve means in
said bore for allowing escape of fluid pressure over a
predetermined value from the supply bore to the exhaust bore.
Description
BACKGROUND OF THE INVENTION
This invention relates to clamping apparatus and more specifically
relates to clamping apparatus embodied in a side-shiftable
mechanical digger or backhoe.
Such mechanical diggers ordinarily have a rigid upright main frame
which can be attached to the rear of a mobile vehicle, such as a
tractor, in a position transverse to the longitudinal central plane
of the vehicle. The frame carries a boom for supporting the digging
implement and the inner end of the boom is pivoted to an upright
swivel post or swing cylinder carried by a slide frame mounted on
the frame. The mechanical digger is generally operated by hydraulic
actuators which are connected to and pressurized by the hydraulic
system of the vehicle.
In order to operate the boom and digging implement in such a manner
as to work closely alongside an obstruction, such as a foundation
or a structural frame, the slide frame may be mounted for movement
along guide means, which form an integral part of the main frame,
so that the swivel post or swing cylinder may be moved to selected
positions along the frame. It is of course necessary to lock the
slide frame to the main frame to prevent sliding during operation
and for this purpose it is known to provide hydraulically applied
clamping means (see French Pat. No. 1,330,860 to Faucheux and U.S.
Pat. No. 3,405,823 to Williams). In these known clamping means, a
clamping block is connected directly to a piston carried by the
slide frame and the piston is hydraulically shiftable to apply the
block against the main frame. Thus, forces tending to shift the
slide frame act through the clamping block crosswise to the axis of
the piston and such forces are undesirable. Also, it has been found
that the overall main frame and slide frame configurations of these
known mechanical diggers do not permit fluid hose placements
allowing unobstructed transverse displacement of the slide frame.
Neither do they allow the main frame to be mounted closely to the
rear axle of the supporting vehicle so as to reduce the moment arm
tending to rotate the vehicle about its rear support wheels.
SUMMARY OF THE INVENTION
According to the present invention, there is provided improved
clamping apparatus for a side-shiftable mechanical digger.
An object of the invention is to provide a clamping block which is
applied by a hydraulically actuated piston which acts through an
intermediate bearing plate.
Another object of the invention is to arrange the piston and
clamping block on the slide frame for action at an angle of
approximately 45.degree. to the horizontal.
A further object is to provide respective complementary surfaces
for horizontal and vertical clamping in the form of a transverse
guide rail on top of the main frame which is received in a recess
on the slide frame and a transverse guide groove in the rear of the
main frame that receives a projection on the slide frame.
Still a further object is to provide a substantially right-angle
corner along the upper rear portion of the main frame and to
provide the clamping block with a complementary right-angle
recess.
Another object is to provide a control valve for the hydraulic
clamping means which may be used with tractors having either open
or closed center hydraulic systems.
These and other objects will become apparent from the following
description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the tractor-mounted mechanical digger in
which the invention is embodied.
FIG. 2 is a sectional view of the main and slide frames clamped
together.
FIG. 3 is a view similar to FIG. 2 but showing the main and slide
frames in the unclamped condition.
FIG. 4 is a view similar to FIG. 2 but showing a modification of
the main and slide frames.
FIG. 5 is a view similar to FIG. 4 but showing the main and slide
frames in the unclamped condition.
FIG. 6 is a partial schematic and sectional view of the control
circuit and valve for controlling the clamp-applying pistons.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 shows a tractor 10 which
supports, adjacent the rear end thereof, a mechanical digger 12
through means of a transverse main frame 14 and a slide frame 16
supported at the rear of and on the main frame 14.
The slide frame 16 is generally U-shaped and has a web 18 with a
forwardly and upwardly inclined front face 19 and respective upper
and lower generally horizontal rearwardly extending arms 20, 22
which provide a mounting for a swing cylinder 24 which operates
about a vertical axis 26 and to which is connected one end of a
digger boom 28. A dipper stick 30 is pivotally connected to the
other end of the digger boom 28 and a bucket 32 is pivotally
connected to the dipper stick 30. Hydraulic actuators 34, 36 and 38
are provided for adjusting the boom, dipper stick and bucket
relative to each other.
Integral with the upper forward corner of the web 18 of the slide
frame 16 is a forward projection 40 which overlies the main frame
14 and carries a clamping mechanism. The clamping mechanism
includes a pair of identical, side-by-side mounted clamp-applying
pistons 42 and 44, having spherical ends 46 and 48, respectively,
received in a respective cylinder 50 and 52. Only the mounting for
the cylinder 50 is shown and it includes a bore 54 inclined
upwardly and rearwardly at approximately 45.degree. from the
horizontal at the juncture of the projection 40 with the web 18 of
the slide frame, the cylinder 50 being tightly received in the bore
54. The bottom of the bore 54 opens into a recess 56 that loosely
receives a clamping block 58. The block 58 has a planar upper
surface on which lies a bearing plate 60, against which bears the
spherical end 46 of the piston 42, the piston 42 being permitted to
shift crosswise relative to the bearing plate 60 and the clamping
block 58. The lower surface of the clamping block 58 has a
right-angle recess 62 which is slidable along and selectively
clampable against a right-angle corner 64 which forms a transverse
guide at the upper rear of the main frame 14.
The slide frame 16 is retained for sliding along and for clamping
engagement with the main frame 14 by means of complementary
counterfaces on the respective frames. These counterfaces take the
form of a transverse guide rail 70 at the top front of the main
frame 14 which is received in a recess 72 in the underside of the
projection 40 of the slide frame 16 and a guide groove 74 in the
lower rear of the main frame 14 into which is disposed a forward
projection 76 of the slide frame 16.
The guide rail 70 is generally rectangular in cross section with
forward, top and rear surfaces 78, 80 and 82 respectively, which
are opposed by forward, top and rear surfaces 84, 86 and 88 of the
recess 72. The guide rail 70 and recess 72 are dimensioned such
that a horizontal under surface 89 which extends from the recess 56
of the projection 40 to the recess 72 will rest upon a horizontal
surface 90 which extends from the corner 64 of the main frame 14 to
the guide rail 70, when the clamping block 58 is not applied as
shown in FIG. 3. Alternatively, the guide rail 70 and recess 72 may
be dimensioned so that the opposed upper surfaces 80 and 86 bear
against each other when the clamping block is not applied.
The groove 74 in the main frame 14 is joined to the corner 64 by a
rear surface 91 which generally parallels the front surface 19 of
the slide frame 16. The groove 74 has a generally vertical front
surface 92, a top surface 93 which inclines upwardly at
approximately 45.degree. to the horizontal to the rear surface 91,
a horizontal bottom surface 94 which terminates in a rear vertical
surface 96 which is in turn the front surface of an upright
retainer lip 98 at the groove entrance. The slide frame projection
76 has front, top, bottom and rear surfaces 100, 102, 104 and 106
respectively, which are opposed to the like surfaces of the groove.
The projection 76 is releasably secured to the web 18 so that the
main frame 14 and slide frame 16 can be more easily assembled. This
connection can be made by screws (not shown) for example, and,
alternatively, the retainer lip 98 may be releasably secured to the
main frame 14 in a similar manner.
In a modified form of the invention illustrated in FIGS. 4 and 5, a
main frame 108 and a slide frame 110 are shown which are shaped
slightly differently and have differently disposed counterfaces at
their respective lower rear and lower front portions than the main
frame 14 and slide frame 16. Specifically, the main frame 108 has a
generally vertical rear surface 112 which merges into a lower
vertical bearing pad 114 and the slide frame 110 has a generally
vertical front surface 116 which merges into a lower vertical
bearing pad 118. A downwardly opening groove 120 at the lower rear
corner of the main frame 108 has a vertical front surface 122 which
forms an included angle of 45.degree. with a downwardly and
rearwardly inclined surface 124, that terminates at the bearing pad
118. The surfaces 122, 124 and the bearing pad 114 form a generally
N-shape and a hooklike projection 126 at the bottom corner of the
slide frame 110 has an opposed N-shaped outline formed by a
vertical front surface 128, a downwardly and rearwardly inclined
surface 130 and the bearing pad 118.
The main and slide frames 108 and 110 respectively, have a guide
rail 132 and upper forward projection 134 which are similar in
construction to the guide rail 70 and projection 40 of the main and
slide frames 14 and 16 and no further description is thought
necessary.
The various hydraulic functions of the mechanical digger 12 are
selectively actuated from a control console or valve housing 140
that is supported on the tractor 10 and covers a valve block 142 to
which is connected a feedline 144 and a return line 146. The manner
in which fluid is transferred from the valve block 142 to the
various functions is by connection means including a fluid hose 147
extending between the valve block 142 and the clamp-applying
pistons 42 and 44. A first set of hoses 148 interconnects the valve
block 142 with a first manifold block 149 carried by the slide
frame 16 and a second set of hoses 150 interconnects the block 149
with a second manifold block 152 carried by the boom 28. Further
hoses (not shown) connect the first manifold block 149 with the
swing cylinder 24 and the second manifold block 152 with the
hydraulic actuators 34, 36 and 38.
The valve block 142 includes a control valve 154 which may be used
with either closed or open center hydraulic systems, as is more
fully explained in the operation below. The control valve 154 is
provided for controlling the clamp-applying pistons 42 and 44, and
includes a valve body 156 in which is a valve bore 158 having an
inlet 160 to which is connected the feed line 144 via a conduit
162. Axially spaced along and intersecting the valve bore 158 are a
supply bore 164, connected to the hose 147, for supplying fluid to
the clamp-applying pistons 42 and 44, and an exhaust bore 166,
connected to the return line 146 via conduit 168. The supply and
exhaust bores 164 and 166, respectively, are interconnected by a
bore 170 in which is a valve seat 172 against which a safety or
relief valve 174 is biased, by a spring 176, to prevent flow from
the supply bore to the exhaust bore.
The valve bore 158 has a first valve seat 178 at the inlet 160. A
second valve seat 180 is defined by an annular shoulder 182
upstream from the intersection with the exhaust bore 166. A pair of
spherical check valves 184 and 186 are oppositely biased against
the seats 178 and 180, respectively, by a spring 188. Pistons 190
and 192 have respective stems 194 and 196, encircled by the spring
188, and head ends 198 and 200 against which the opposite ends of
the spring 188 are seated.
To exhaust fluid pressurizing the pistons 42 and 44, it is
necessary to prevent further fluid from entering the supply bore
164 by seating the check valve 184 while simultaneously permitting
flow from the supply bore 164 to enter the exhaust bore 166 by
unseating the check valve 186. This is accomplished by structure
which includes a third piston or ram 202 having a head end 206 and
a stem 204 bearing against the check valve 186. A spring 208 has
opposite ends bearing against the head end 206 and a plunger 210
that is slidably mounted in the valve bore 158. A control lever 212
is pivoted on a pin 214 normal to the axis of the valve bore 158.
The lever includes a cam 216 engaging the plunger 210. To function
properly, the spring 208 must exert a force greater than the feed
pressure in order that plunger movement will be transferred through
the spring 208 to the piston 198 to unseat the check valve 186,
which in turn acts through the piston 206 to compress the spring
188 until the stem 196 engages the stem 194 of the piston 190,
which urges the check valve 184 tightly against the valve seat
178.
In operation of the embodiment illustrated in FIGS. 2 and 3, upon
exhausting the fluid pressure from the top of the cylinders 50 and
52, in a manner set forth below, the slide frame 16 will assume the
unclamped position of FIG. 2 wherein the undersurface 89 of the
projection 40 rests upon the upper surface 90 of the main frame 14.
The slide frame may then be displaced to a selected transverse
position by placing the bucket 32 on the ground and actuating the
actuator 38 in a manner well known in the art. Once the slide frame
16 is at a desired location, it may be secured by pressurizing the
top of the cylinders 50 and 52 by placing the control lever 212 in
the position illustrated in FIG. 6 wherein fluid under pressure in
the feed line 144, the conduit 162 and the inlet 160 holds the
check valve 184 off the seat 178 and at the same time securely
seats the check valve 186 against the seat 180, thus there is fluid
under pressure in the supply bore 16, the hose 147 and the
cylinders 50 and 52 and the pistons 42 and 44 are extended. If the
tractor 10 is provided with a closed center hydraulic system, as
soon as equal fluid pressure exists on the opposite sides of the
check valve 184, the spring 188 will act to seat the check valve
184 to interrupt flow through the inlet 160, the equal pressure
being possible due to the fact that in a closed center system the
delivery pump disconnects automatically as soon as a predetermined
pressure exists in the system. On the other hand, if the tractor 10
is provided with an open center hydraulic system, a system wherein
the pump delivers fluid pressure continuously, the safety or relief
valve 174 opens at a predetermined pressure to connect the supply
bore 164 with the exhaust bore via the bore 170.
Only the operation of the piston 42 is described, it being
understood that the operation of the piston 44 is identical. As the
piston 42 is extended, the spherical end 46 of the piston bears
against the bearing plate 60 to force the clamping block 58 against
the right-angle corner 64 of the main frame 14. The clamping force
being applied at approximately 45.degree. is divided into
substantially equal horizontal and vertical forces. The reaction to
the force applied by the piston 42 will cause the slide frame to
shift upwardly and rearwardly to the clamped position illustrated
in FIG. 2 wherein the respective forward surfaces 78 and 84 of the
guide rail 70 and recess 72 are in bearing engagement and the
respective top surfaces 93, 102 and rearward surfaces 96, 106 are
in engagement. It should be noted that as the slide frame 16 shifts
upwardly and rearwardly, the piston 42 moves crosswise relative to
the bearing plate 60 and the clamping block 58.
The main and slide frames 108 and 110 in the embodiments
illustrated in FIGS. 4 and 5 are clamped in a manner quite similar
to that described above, the only difference being that additional
clamping surface area is presented by the respective upper surfaces
124 and 130 of the groove 120 and the projection 126 and the
vertical bearing pads 114 and 118.
The clamping pressure to the pistons 42 and 44 may be released by
rotating the control lever 212 of the control valve 154 clockwise
whereupon the cam 216 will engage the plunger 206 and move the
plunger axially to urge the relatively stiff spring 208 against the
piston 202 and unseat the check valve 186 which will in turn be
moved axially enough to move the piston 192 against the piston 190
to seat the check valve 184, thus simultaneously preventing fluid
pressure into the supply bore 164 while allowing communication
between the supply and exhaust bores 164 and 166 via the valve bore
158.
* * * * *