Au@ 27, 1935.
o'. F. KUHLMAN -
2,012,430
LIFTING JACK
Filed May 5l, 1934
mv NToR
05042 ?î abz/wmv
Patented Aug. 27, 1935
UNITED STATES PATENT orties
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2,012,430
LIFTING JACK
Oscar F. Kuhlman, York, Pa., assigner to Ameri
can Chain Company, Inc., Bridgeport, Conn.,
a corporation of New York
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Application yMay 31, 1934, serial> No. 728,250
8 Claims. (ci. :zar-89)>
The present invention ’relates to lifting ’jacks
and more particularly to jacks of the 'type adapt
ed to raise both front wheels oi an automobile
simultaneously.
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An object of the invention‘is to'provide> a jack
adapted particularly for use with automobiles
having so-called “knee-action” front Wheels, that
is, wheels which are individually sprung‘and ca
pable of individual vertical motion with respect
to the chassis.
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Heretofore jacks have been designed to engage
a chassis at a point midway between the front
wheels, but inthe case of knee-action structures
such application of the jack would result Vinitially
in merely expanding the springs as`1they were
relieved of the weight of the chassis and the
wheels would not leave the ground until the chas
sis was raised beyond the limit of expansion oi’
the springs. This necessitates operating the jack
20 to a much higher elevation than with cars `not
425
30
wheel,l which "links’are hinged to the chassis.
Each lower pair of links carries a seat member
i4 for‘the lower end of `a coil spring i5, the upper
end of which bears against a suitable seat i5 car- `10
ried by the chassis. Thus, each wheel ís free to
swing vertically with respect to the chassis inde
pendently of the other Wheel, such vertical move
ment effecting expansion or contraction of the
spring I5 associated with said wheel.
,
i5
It will be obvious that when a jack is applied
to the chassis inthe usual manner it will lift the
weight of the chassis oiî the springs it permit
ting the latter to expand, and the wheels will re
having the >knee-action, which entails useless'ef
main on the ground until the entire spring ex- 20
pansion has taken place or until some stop is en
fort, and in some cases the jacks are .incapable
of operating to a sufficient height to lift the knee
countered, such, for instance, as bottoming of the
shock absorbers commonly provided on. the front
action wheels oir the ground.
wheels.
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An object of the present invention is to ‘provide
a jack adapted to engage the knee-action mecha
nism instead of the chassis, so that when the jack
is operated it will lift the wheels off the ground
without having first to allow for ‘elongation of the
springs.
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Another object of the invention is to provide `a
dual rest-plate which may be substituted for the
ordinary rest plate of a jack, said dual rest-,plate
having a wide span so as to engage such part
of the knee-action mechanism as will insure lift
ing of the wheels from the ground without the
necessity of taking up elongation of the springs.
Another object of the invention is to provide
a dual rest-plate having individual work supports
or chairs pivotally mounted so that they will
adapt themselves individually to the knee-action
mechanism which they support.
Other objects and advantages of my invention
Will appear in the following description of a pre
ferred embodiment and thereafter the novelty
and scope of the invention will be pointed out
in the claims.
In the accompanying drawing;
Figure 1 is a view in perspective of a jack pro
50 vided with a dual rest-plate supporting the front
end of a car having knee action front wheels;
Fig. 2 is a view in longitudinal section of the
dual rest-plate, the section being taken on the
line 2-2 of Fig. 3; and
55
“Knee-action” mechanism varies with differ
`ent'makes of cars, but a typical knee-action link
age may be seen in Fig. l. The car, fragmentally
shown in said ñgure, has a chassis lo to which
front wheelsY I `I are connected by suitable links. `5
`There are `two lower links i2‘and i3 for each
y
Fig. 3 is a top plan view of the dual rest-plate.
The jack l1, shown in Fig. 1, may be of stand- 25
»ard make, having a plunger or lifting arm i8
adapted to support the usual rest-plate. As
Shown in Fig. 1 the lifting arm is bifurcated at
its upper end and a socket member i9 is em
braced between the arms, being pivoted thereto 30
by means of trunnions (not shown) so that the
socket member is capable of movement about a
horizontal axis. The socket member has a verti
cal socket or bore 20 therethrough adapted tore
ceive a stud projecting from the bottom of the 35
rest plate.
Instead of the ordinary rest-plate which is
adapted to engage a very limited portion of the
chassis, I provide a dual rest-plate indicated gen
erally by the reference numeral 2i. This dual 40
rest-plate, as shown clearly in
2 and 3, com
prises a beam formed of a pair of arms 22. A
central block 23 connects these arms in parallel
and mutually spaced relation. This block has a
downwardly projecting stud 24 which is turned 45
to ñt the socket 2 so that the rest plate may
swivel with respect to the socket member. The
beam provides suflicient reach to engage the
spring seats I4 or such other parts of the knee
50
action mechanism as would be most suitable.
Supported on the beam at each end thereof is
a chair 25. Each chair is in the form of a plate
preferably having an upstanding rim 2t“ about a
part of its periphery.
Extending downwardly
from each plate are lugs 21 which are pivotally 55
2,012,430.r
2
connected to the arms 22 by means of a hinge
pin 23. As shown in Fig. 2, the chairs 25 are
supported slightly above the level of the arms 22
pads 2Q at the inner end of the plate, which nor
comprising a transverse beam mounted to swivel
with respect to said member, and a pair of chairs
mounted at opposite ends of the beam and adapted
to oscillate in the plane of the beam on axes lying
in a plane normal to the axis on which the beam
mally rests on the arms Z2, as .shown in Fig. 2.
swivels.
so that they are allowed limited oscillatory move
ment on the pins 2B. Each chair is formed with
However, the chairs may be oscillated to the posi
tion shown in Fig. l so as to adapt themselves to
10 the parts they engage.
y15
_
4. A lifting jack comprising a lifting member,
axis, a transverse beam having a swivel stud en
gaging the socket of said block, and a pair of
Vchairs pivotally mounted at opposite ends of said
the dual rest~`plate may be removed and replaced
with an ordinary single rest-plate which will
5. A lifting jack comprising a lifting member,
a socket block pivotally mounted in said member
and adapted to turn on a substantially horizon
tal axis, a transverse beam having a swivel stud
engaging the socket of said block, and a pair oi’
beam,vthe pivotal axes of the chairs lying in a
for lifting the knee-action wheels. At other times, ‘ plane normal to the axis of said stud.
linee-action mechanism.
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As applied to a car of the type shown in Fig. l,
the jack is maneuvered under the forward ’end of
the chassis until the chairs 25 are substantially
centered under the spring seats Eli-_k Then when
the jack is operated to raise the arm I8 said
25 spring seats will be lifted raising the Vwheels with
out any useless spring extension. The rims’ZE are
provided as safety means to retain the spring seats
20
in the chairs.
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While I have described a preferred embodiment
30 of my invention it will be understood that this is
to be taken as illustrative and not limitative and
that ï reserve the right to make various changes
in form, construction and arrangement of parts
without departing from the spirit and scope of
the following'claims.
I claim:
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l. A lifting jack having a lifting member and
a dual rest-plate carried thereby, said rest-plate
comprising a transverse beam mounted to swivel
40 with respect to said member on a substantially
vertical axis, and a pair of chairs mounted at
opposite ends of the beam and adapted to oscil
late in the plane of the beam on substantially
horizonal axes.
45
Ul
a socket block pivotally mounted in said member
and adapted to turn on a substantially horizontal
Preferably, the dual rest-plate is not made a
permanent part of the jack but is merely connect
ed thereto by inserting the pin or stud 24 into the
socket ZD whenever it is desired to adapt the jack
adapt the jack for use on cars not equipped with
35
a dual rest plate carried thereby, said rest plate
2. A lifting jack comprising a lifting member,
a socket block pivotally mounted in said mem
ber and adapted to turn on a horizontal axis, a
transverse beam removably mounted on said block
and having a swivel stud engaging the socket of
said block, and a pair of. chairs pivotally mount~
ed at opposite ends of said beam and having
limited oscillatory movement in the plane of said
beam.
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3. A liftingY jack having 'a lifting member, and
chairs pivotally mounted at opposite ends of said
beam, theY pivotal axes of the chairs lying in a
plane normal to the axis of said stud, said chairs
overlying the beam and being limited thereby in
their oscillatory movements.
6. As an article of manufacture, a rest plate
for axlifting jack, said rest plate comprising a
supporting'beam, chairs pivoted on the beam ad
jacent opposite ends thereof and adapted to swing
in the plane of the beam, and means at the center 30
of the beam for effecting a swivel connection of
the beam to the jack, the pivotal axes of the chairs
lying in a plane normal to the swivel axis of the
beam.
’7. As an article of manufacture, a rest plate for
a lifting jack, said rest plate comprising a .sup
porting beam, chairs pivoted on the beam ad
jacent opposite ends thereof, and means at the
center of the beam for effecting a swivel con
nection of the beam to the jack, the pivotal axes
of the chairs lying in a plane normal to the swivel
axis of. the beam, said chairs overlying the beam
and being limited thereby in their oscillatory
movements.
8. As an article of manufacture, a rest plate
for a lifting jack, said rest plate comprising a sup~
porting beam having
ce itral depending stud
adapted for swivel connection to the jack, a pair
of chairs pivoted respectively adjacent opposite
ends of the beam, the pivotal axes of the chairs ly« 50
ing in a plane normal to the axis cf said stud, and
cooperating means on the chairs and beam for
limiting oscillation of said chairs.
OSCAR F. KUHLMAN.