Патент USA US2553827

May 22, 1951
HYDRAULIC
C, H. MARTIN
`2,553,826
POWER TRANSMISSION FOR USE WITH ROTATABLE
ENGINE DRIVEN POWER TAKE-OFF SHAF‘TS
Filed Feb. 15, 1947
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2 Sheets-Sheet 1
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May 22,V 1951
HYDRAULIC
C. H. MARTIN
2,553,826
POWER TRANSMISSION FOR USE WITH ROTATABLE
ENGINE DRIVEN POWER TAKE-OFF SHAFTS
Filed Feb. l5, 1947
2 Sheets-Sheet 2
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Patented May 22, 1951
Arre
«UNITED ST'lES
2,553,826
HYDRAULIC POWER TRANSMISSION FÜR
USE WITH >ROTA'ÑABLIEI 'ENGINE-DRIVEN
POWER TAKE-OFF SHAFTS
Charles H. Martin, Huntington V‘ll’ark, Calif., as
signor, by mesne assignments, to Farm-Aid
Implement Company, Norwalk, Calif., a corpo
ration ci’ ACalifornia
Application February 15, 1947, Serial No. y'728,815
2 Claims.
(Cl. 60--54'.5)
l
clutch, thereby eliminating the need for the
usual'valves.
Another object is to provide a hydraulic power
transmission device in which the generation of
working implements connected thereto, and Ul pressure is automatically stopped and held at the
end of the power stroke so that the system is pro
which provides a means for converting thepower
tected against the development of excessive pres
vof an engine-driven rotating shaft into hydraulic
sures without relying on pressure relief by-pass
power and then utilizing such'hydraulic power to
valves.
actuate a remote power lift on the implement.
’Still another object of the invention is the pro
Specifically, the present invention was designed
vision of a hydraulic power lift device embodying
for use on the small, four-wheel drive, personnel
means whereby the implements may be -dropped
carrying vehicle developed for the military serv
quickly to ground-working position.
-ices and known popularly as the “,ieep.” vBecause
These objects are achieved in the present in
of its light weight, four-wheel drive, and gen
vention by the provisionv of a vreversible gear
erally rugged construction, the jeep has been `
transmission which 'is adapted to be connected
found to be ’ideally suited for use on small farms
to the power take-oil shaft to be driven thereby
las a utility'vehicle, and is extensively employed
and which is operative to drive a piston :axially
as a tractor to pullground working implements
within ua `master cylinder ‘to displace fluid con
of all kinds. The versatility `oi the postwar jeep
has been enhanced still further by the addition oi 20 tained therein. The displaced fluid is conveyed
through a line to the working cylinder of a re
an engine-driven power take-oil shaft, making it
mote hydraulic power lift or other ‘operating
possible to drive equipment such as saws, thresh
mechanism to Vactuate -the same, and operation'of
ers, hammermills, air compressors, and the like.
-the device is accomplished‘by engaging one of-two
There is one shortcoming of the jeep, however,
Yclutches to drive the piston in one direction or
and that’is its lack 'of any provision for the actu
'the other. A valve is provided in the system for
ation of >hydraulic power lift equipment on 'the
lay-passing hydraulic fluid from 'the wor-king 4cyl
implement. As aresult, implements designed for
inder to a reservoir tank when it is desired »to drop
the jeep have generally'been'limited to manually
the implements quickly to ground-working posi
operated lifting levers or mechanical lifts utiliz
tion. In this way', fluid inthe working cylinder
ing wheel-driven half-revolution clutches, neither `
can be displacd more rapidly by the piston than
0f which is as satisfactory for certain classes of
if it weredrawn onc by the master cylinder, vthereequipment as the hydraulic power lift.
by permitting a fast return of the working piston
One of the principal objects of the present lin
with a correspondingly quick drop of'the imple
vention, therefore, is "to provide a new and im- ‘
ments carried thereby. The flud in the reservoir
proved hydraulic power transmission device ‘
tank is then drawn into the master cylinder
adapted to be mounted on ra propelling ‘vehicle
through a ycheck valve.
and driven by the engine thereof to provide a
The above and other objects and advantages
lsource of fluid pressure for actuating 'hydraulic
of the‘invention will become apparent to those
equipment on the vehicle or implement.
skilled in the art upon consideration of the fol
Another important object of the invention is
lowing detailed descriptionof the preferred-em
to Lprovide a self-containedvpower lift 4mechanism
bodiment thereof, reference being had to the
which'is adapted to be driven from the power
`drawings in which:
take-off shaft of a `jeep or other .automotive Ve
Figure l is a partially sectioned schematic
hicle, and which vrequires-no structural alteration
drawing oi a hydraulic power transmission mech
.of the vehicleor its transmission system.
anism embodying the principles of the invention;
Figure 2 is an enlarged vertical section, taken
Another object rof the .invention is to provide
aidevice -for l„generating fluid pressure, in which
through the gear box of the same;
Figure 3 is a sectional view, taken along the
the fluid is vacted upon only during the power
line 3-3 of Figure 2;
stroke »and is not constantly circulated with re
Figure ‘l is a sectional view taken along lthe
sultant loss of power, asin prior devices.
line ê-Al of Figure 2;
A -further »object of the invention is to provide
Figure 5 is a fragmentary top plan View ofthe
>a-device of the class described in which the gen
linkage arrangement for stopping the operation
eration of fluid pressure -for the power stroke is
started or `stopped by engaging or disengaging'a 55 of the device >at theeend of the power stroke; and
The present invention relates generally to hy
draulic power transmission devices, and more
particularly to a device which is adapted to be
>mounted on an automotive vehicle having ground
2,553,826
3
4
Figure 6 is an enlarged sectional view of the
vaive which is connected to the fluid line and
al' ñxed thereto between the bearings 40 and 44,
said sprocket being connected by a chain S3 to
which permits the implements to drop quickly to
their operative, ground-working position.
The purpose of the sprocket drive 6l, 68, 69 is
a‘ driven sprocket 55 mounted on the tube 5l.
In the drawings, the rear end of the body of
the vehicie to which the device is attached is des
ignated by the reference numeral lil, and project
to drive the tube 5I in one direction from the
torque tube 37, while the gears 46, 55 serve to
ing rearwardly therefrom is a splined power take
off shaft H which is driven from the engine of
the vehicle, The hydraulic power transmission
the front torque tube 35, both torque tubes being
device of the invention comprises a gear box I2
which is adapted to be mounted on the vehicle
clutches 3Q and 35. Thus the piston I5 can be
driven toward the rear end of the master cylin
body [email protected] by brackets i3; a master cylinder I4
having a piston i5 connected to the gearing in
the box i2 to be moved thereby; and a working
cylinder i6 which is connected by a flexible hy
draulic line l? to the master cylinder. A piston
lil in the cylinder le is operatively connected to
der M by engaging one of the clutches 34, 35 to
rotate the tube 5i in one direction, or toward the
front end of the master cylinder by engaging the
other clutch. Rearward movement of the piston
I5 causes a positive displacement of the fluid
contained in the rear end of the master cylinder
mechanism on the implement (not shown) to ac
i4, and this displaced fluid is transmitted
through the line Il to the right hand end of the
tuate the same.
The gear box i2 includes a generally rectangu~
lar housing 2D having bushings 2l at opposite
ends thereof, which serve as journals for a shaft
22. The shaft 22 projects forwardly through the
front wall of the housing 2E! and has a sprocket f
23 ñxed to its outer end, which is connected by
a chain 24 to a drive sprocket 25 mounted on the
splined power take-off shaft I l. Between the two
drive the tube 5i in the other direction from
rotatable in the same direction when connected
with the shaft 26 through their respective
working cylinder I6 to drive the piston I8 for
wardly. Since the working cylinder lâ is usually
connected to a power lift and is therefore loaded
in one direction only, it is not necessary to pro
vide for the application of fluid pressure to the
opposite side of the piston to return the same to
the right hand end of the cylinder I5. Fluid in
the right hand end of the working cylinder It is
placed under pressure from the load applied on
the piston i8 by the weight of the raised tools,
and is forced back through the line I1 as the
master cylinder piston le is moved to the left.
bushings 2l, the shaft 22 is enlarged in diameter
at 26 and splined at 21 and 28 to receive the cor LSU
respondingly splined hubs of the driving mem
bers 3B and 3| of clutches 32 and 33, respectively.
If it should be desirable to have a two-way
The two clutches 32, 33 are shown illustratively
power stroke of the working piston I8, it is neces
as cone clutches, but it will be understood, of
course, that any other form of clutch might be 35 sary only to provide another line connecting the
left hand end of the master cylinder I4 with the
used with equal advantage. The clutch driv
left hand end of the working cylinder I5; addy
ing members 3G, 3! are slidable on their splines
another cup to each of the pistons facing toward
21, 28 for movement into and out of engagement
the left so that the pistons will hold pressure
with driven members 3d and 35 which are fixedly
mounted on tOrque tubes 35i and 3l'. The torque 40 from either direction; and fill both sides of both
cylinders with hydraulic fluid.
tubes 36, 3l are rotatably mounted end to end on
the enlarged portion 25 of the shaft, and are
Selective engagement of the clutches 30, 3l is
effected through a lever 13 which is pivoted at
supported at their adjacent ends in ball bear
ings fli) which are held in a common bearing
'I4 on an upstanding bracket ‘I5 on the top cover
support member 4l extending transversely across 45 plate 'I6 of the housing 2b. At its bottom end, the
the housing 25) from one wall to the other. The
front torque tube 35 is additionally supported
lever 'i3 is provided with a pin ll which passes
through an elongated slot 'I3 formed in a bracket
8B ñxed to a bar 8i. The bar 8| is disposed on
by a ball bearing 42 mounted in a support mem
the inside of the housing 2i) and the bracket 8€!
ber 43, while the rear torque tube 3l is held by a
ball bearing 5.4 mounted in a support member 45. 50 projects upwardly therefrom through a slot 32
in the cover plate. The bar 8l is slidably held
Fixedly mounted on the front torque tube 3S
against the bottom surface of the plate 'I6 by two
between the bearings ¿le and 42 is a gear 46 which
longitudinally spaced guide brackets 83 and 84,
meshes with a companionate gear [email protected] mounted
and the ends of the bar are bent downwardly and
on a tubular shaft 5i disposed below the shaft
25 and parallel thereto. The tubular shaft 5l is 55 provided with forks 8l’ which engage annular
grooves 85 and Bü in the clutch driving members
journaled at its ends in bushings 52 and 53 which
3D, 3i, respectively. Thus, when the lever 13 is
are mounted in the end walls of the housing 2S,
shifted forwardly to the position indicated in
and is provided with an internal thread 54 ex
dot-dash lines at A, the bar 8! is moved rear
tending from one end to the other. Slidably dis
posed within the tube 5i and projecting from the 60 wardly, engaging the driving member 39 of
rear end thereof is a rod 55 having raised
clutch 32 with its driven member 34, while at
the same time, the driving member 3l of clutchv
threads 56 at its inner end which mesh with the
53 is separated still further from its driven mem
threads 54 of the tube. The rear end of the rod
ber. With the clutch 32 thus engaged, power
55 extends into the master cylinder iêi and is
provided with a threaded stud @El of reduced di 65 from the shaft 25 is transmitted to the front
torque tube 35 and through gears 46, 50 to drive
ameter. A circular plate 5i is mounted on the
stud 60 abutting against the shoulder formed
the tube 5l in one direction, causing the rod 55
at the junction of the stud with the rod, and
to be moved to the right, or left, depending upo'n
clamped between the plate 6i and a washer S2
the direction of rotation of the shaft 26 and the
is a cup 63 of leather or rubber, having a. rear 70 lead of threads 54. When the lever 13 is swung
wardly directed annular flange which bears
against the inside wall of the cylinder. A nut
rearwardly to the position indicated at B, how
54 is threaded on the stud 6i and serves to draw
gaged with its driven member 35, while the driv~
ing member 3Q of clutch 32 is separated from its
driven member 34. In this condition, power from
the washer E2 tight against the cup.
The rear torque tube 3l has a driving sprocket
ever, the driving member 3i of clutch 33 is en
[email protected]
5
vthe shaft 26 is transmitted through clutch v33
to the rear torque tube ‘31 and thence through
sprockets 61 and 69 to the tube 5I. Since the
sprocket SS turns in the saine direction as
sprocket (il, whereas gear 50 turns in the op
posite direction to gear d5, rotation of the tube
5| when driven by the sprockets is in the op
posite direction to that when driven by the gears.
With the tube 5i thus turning in the other di
rection, the rod 55 is moved in >the-opposite di
rection to that traveled when the drive is through
the gears.
In order to prevent the rod 55 from iturning
with the tube 5I, an arm 9i? Vis Aiixedly mounted
on the rod 55 between the housing 2Q and mas
ter cylinder It and projects upwardly therefrom.
The top end of the rod passes through an -elon
gated slot Si formed in a rearwardly projecting
bar 92 slidably mounted on the top surface of
the cover plate "lâ parallel to the rod 55. The
>bar 82 is slidably held by a guide bracket 9,3
-ñxed to the top surface of the plate 'Ië at its
rear edge, and projecting upwardly and for
wardly from the front end of the bar 92 is an arm
2li- which is connected by a pin 95 to the lever 'i3
above the pivot pin le.
In the illustrative form of the invention shown,
the rod 55 is caused to move to the right when
the lever 'i3 is shifted to position A, and as thc
e
the tank Hill and to _the yright hand end of the
master cylinder Iâ through 4a check valve iûiì.
The valve |32 may be of any desired type, and
is shown typically as comprising a housing ||û
having fluid passages provided therein which
vcommunicate with the lines I?i and Iûîi. Slid
ably disposed within the housing is a valve poppet
I II which is yieldingly held onto its seat by a
spring II2. At its upper end, the stem of the
valve poppet I I I is connected by a pin I I3 to one
arm of a bell-crank Hä which is pivoted at |I5
on a bracket Iliì on the valve housing. The up
wardly extending other arm of the bell crank is
connected to a push-pull rod |29 which extends
forwardly therefrom and is connected to one end
-of an equalizer bar I2I. The other end of the
equalizer bar is connected by a link I2?. to the
clutch lever 13. Pivotally connected to the equal
izer bar |2| between the rod [email protected] and link |22 is
a forwardly extending link |23 which is con
nected at its front end by a pin I 2t to a manually
operable control handle |725 pivoted at §26 on a
bracket I2? mounted on the vehicle body Iû.
The linkage arrangement described above en
ables the operator to shift the clutch lever '.13
back to position B and simultaneously open the
valve I€l2 Iby merely moving the one control
handle |25 rearwardly. The equalizer bar I 2|
distributes the control movement of the handle
master cylinder piston I5 approaches the end or" 30 |25 between the `clutch lever i3 and valve-actuat
ing-bell crank lill according 'to their respective
its travel in this direction, the arm âiì engages
the right hand end of the -slot “5| in bar 92. At
'this 4.point the lever 'I3 ¿ís'zpic'ked .up ’by >the arm
[email protected] and shifted forwardly to its :center >neutral
position, disengaging clutch 32 which„as pointed
out previously, is engaged when the lever is at
position A. With the power to the 'tubular-drive
shaft 5| thus cut oiî, piston I5 cornes to a stop
and `there is no further displacement of fluid
fromvthe right hand end of the master cylinder iii.
needs, and takes care of the difference in their
operational movement. With the lever "i3 moved
back to position B, the >forward clutch 32 is
engaged, causing the piston l5 to begin its rela
‘tively slow rtravel toward the left. At the same
time, however, the simultaneous opening of the
valve |92 permits iiuid from the working cyl
inder Ile to empty yrapid-ly into the reservoir tank
IGA under'the pressuresexerted'by the implement
Since the arm 9i! Yis now engaged by the right
loaded piston IS, and as Va lresult the implements
hand end of the slot Él, the lever 'i3 is Aprevented
from moving to the left >or back toward ‘position
A, and the only direction of control movement
available is toward position B. When the lever
is swung over to position B, clutch 33 isengaged,
moving the rod 55 and piston I5 to the left. As
the piston I 5 approaches 'the end of its travel in
are dropped quickly to ground-engaging position.
The fluid discharged into the reservoir tank ’los
is then drawn into the master cylinder ill through
the >line it‘ii and check valve Ifile by the slow
.moving piston 'I5 until the latter reaches the
end of its travel.
When ‘the control handle i25 is pulled for
wardly, the lever 'i3 is shifted to position A to
this direction, the .arm ed engages. the left hand
end-of slot 9i and moves the lever i3 Jback to 50 .drive the piston .i5 rearwardly. Since the valve
.puppet I II is normally seated,'the bell crank i àß
.neutral position again to discngage the clutch and
is :prevented from rocking in acounterclockwise
bring the piston I5 to a stop. The pitch of the
direction, and the rod é2ll is therefore held sta
threads Sli is such that the driving connection
tionary. During rearward movement of the pis
between tube 5| and rod 55 is irreversible in
nature, and no amount of thrust by the piston 55 ton l5, fluid from the master cylinder is pre
vented from discharging into the reservoir tank
I5 on rod 55 will produce rotation of the tube 5|.
|34 by the check valve |36.
A by-pass arrangement is provided to permit
The operation and advantages oi the present
the fast return or” the working piston |8 to thc
invention are believed to be self-evident from the
right hand end of the cylinder I6 so that im
foregoing discussion. Since the fluid in the mas
plements may be dropped quicly from raised 60 ter cylinder lll is acted upon only during the
position to ground-working position. The func
power stroke when one of the clutches 32, 33 is
tion of this by-pass arrangement is to provide
engaged, there is no loss of power from constant
means for receiving the entire volume of fluid
circulation of the iiuid as in prior devices. The
displaced from the right hand end of the work 65 device may be used in one form as a self-con
ing cylinder by the implement-loaded piston and
tained hydraulic power transmission mechanism
holding the iiuid until the same has been drawn
in which the gear box I2, master cylinder It, and
into the master cylinder I4 by the relatively slow
working cylinder l5 are all integrally mounted
on an implement and the only connection with
moving piston I5. Accordingly, the »by-pass in
cludes a T-connection lili! which is connected 70 the vehicle is to the power take-on shaft II by
the sprockets 23, 25 and chain 24. Alternatively,
into the line Il and which has a branch line
the device may be used in another manner as a
It! leading to a valve |82. A line |03 extends
source of fluid pressure for working cylinders
from the valve H32 to the upper end of a res
mounted on several different implements, and
ervoir tank Itâ, with which it is connected. An
in this case the gear box I2 and master cylinder
other line Iüiì is connected to the lower end of
2,553,826
7
I4 would be mounted on the vehicle more or less
permanently and removed therefrom only when
required by convenience. When the device is
to be used in this manner, a quick detachable
fluid line coupling 9S may be provided at the dis
charge end of the master cylinder i4 to receive
a coupling member Sl on the line il', so that the
line may be quickly and easily connected to the
master cylinder. 'Such a coupling should pref
erably be of the type employing a double check
valve to prevent loss of fluid from either the cylin
der lâ or line il when the latter is disconnected.
While I have shown and described in some de
tail what I consider to be the preferred form
of my invention, it is to be unde-rstood that
changes may be made in the shape and arrange
ment of the several parts without departing from
the broad scope of the invention as deiined in
the appended claims.
8
said power lift device comprising a master cylin
der and piston, a working cylinder and piston, a
reversible drive mechanism operatively connected
with said power take-off shaft, a .screw threaded
member supported for rotation, a rod connected
at one end to the piston in said master cylinder
and having threaded connection with said screw
member, whereby said piston may be driven in
one direction or the other within the master cylin
der, a hydraulic line connecting one end of said
master cylinder with one end of said working
cylinder whereby fluid displaced by the move.1 ent
of the piston in the master cylinder is conveyed
to the working cylinder to move the piston there
in, said working piston being adapted to be con
nected to said implements to raise or lower the
same, a reservoir tank, valve means for by-pass
ing fluid from said hydraulic line to said reservoir
tank to permit the fast return of the implement
I claim:
20 loaded working piston, a check-valve controlled
1. A hydraulic power lift device for use with
return line from said reservoir tank to said master
a vehicle adapted to have ground-working im
plements mounted thereon for movement be
tween raised and lowered positions, and said
vehicle having an engine-driven power >take-oil
shaft, said power lift device comprising a mas
ter cylinder and piston, a working cylinder and
piston, reversible transmission means operatively
connected with said power take-01T shaft for driv
ing the piston in said master cylinder from one
end thereof to the other, a hydraulic line con
cylinder, said master cylinder drawing iiuid from
said reservoir tank until the piston has reached
the end of its return travel,
control means
operatively connected to both said reversible drive
mechanism and to said valve means whereby said
master cylinder piston is started on its return
stroke and said valve means is simultaneously
opened.
CHARLES H. MARTIN.
REFERENCES CITED
necting one end of said master cylinder with one
end of said working cylinder whereby fluid dis
placed by the movement of the piston in the mas
ter cylinder is conveyed to the working cylinder
rile of this patent:
to move the piston therein, said working piston
being adapted to be connected to said implements
Number
to raise or lower the same, a reservoir tank con
nected to said hydraulic line, valve means opera-
tive to by-pass fluid from said working cylinder
to said reservoir tank to permit the fast return
of the implement-loaded working piston, and a
check-valve controlled return line from said re
servoir tank to said master cylinder, said mas
ter cylinder drawing iiuid from said reservoir 45
tank until the piston has reached the end or”
its return travel.
2. A hydraulic power lift device i'or use with a
vehicle adapted to have ground-working imple
ments mounted thereon for movement between
raised and lowered positions, and said vehicle
having an engine-driven power take-off shaft,
The following references are of record in the
UNITED STATES PATENTS
Name
Date
865,201
1,439,304
1,754,688
1,885,936
1,983,884
2,252,482
2,322,133
2,361,326
2,433,990
2,481,477
2,487,699
Morton __________ __ Sept. 3,
Fraser __________ __ Dec. 19,
McFarlane ______ __ Api". 15,
Bowen ____________ __ Nov. 8,
Hele-Shaw ______ __ Dec. 11,
Gates ___________ _ Aug. 12,
Hettelsater ______ __ June 15,
Silver __________ __ Oct. 24,
Hardy __________ __ Jan. 6,
Peery __________ __ Sept. 6,
Fie‘gel ____________ __ Nov. 8,
1907
1922
1930
1932
1934
1941
1943
1944
1948
1949
1949
FOREIGN PATENTS
Number
41,164
440,087
Country
Date
Denmark ________ __ |Nov. 16, 1929
Germany ________ __ Jan. 28. 192'..7