US1805588A - Hydraulic jack - Google Patents

Description

MaY 19,-19311- R. E. MANLEf y v 1,805,588

- HYDRAULIC JACK `Filed Jan. 5, 192e 4 sheets-shed 1 i mi R. E. MANLEY HYDRAULIC. JACK IMay 19, 1931.

4 Sheds-Sheet 2 x6 Y A 1g/Q /y .MAQ

Filed Jan. 5, 1926 .lle

May 19, 1931.

R. E. MAN LEY HYDRAULIC JACK FiledvJan. 5, 1,926y 4 Sheets-Sheet 5,

My 19; 1931- R. E. MANLl-:Y 1,805,588`

HYDRAULIC JACK Filed Jan. l511926 4 sheets-sheet 4 Patented May 19,1931

vUNITED. STATES- PATENT' OFFICE ROBERT E. MAYNLEY, F YORK, PENNSYLVANIA., ASSIGNR TU MANLEY MANUFACTUR- ING COMPANY, OF YORK, PENNSYLVANIA, A CORPORATION OF' DELAWARE HYDRAULIC JACK Application led January 5, 1926.A Serial No. 79,435.

rlhis invention relates to automobile jacks, and has for its principal .object the provision of a substantially fool-proof hydraulic jack havinga high lift..

A further object of the present invention lies in the provision of a jack which can accommodate itself to avery small clearance, is simple to operate, and yet has sufficient capacity to raise a vehicle or othervload to a satisfactory height. A still further object of this invention is to provide a hydraulic jack which will be leak proof So as not to spill the "oil on the floor. 'Other objects of the invention will be apparent from the following description and claims. Y

Of all piecesv of garage equipment it is believed the jack is most subject to abuse, and it is therefore essential that an automobile jack be made as near fool-proof as possible,l

and particularly as regards to some means for preventing a thoughtless person' from applying destructive power after the jack has been run to its maximum height, or when the lifting portion of the jack has encountered a load beyond the possibilities of the jack.4

With the present popularity of the balloon tire it has become quite necessary that a garage jack shall have a very low clearance and it is equally essential that theY jack must be capable of taking a very heavy pleasure car to a rather greater height than required with high pressure tires. It is also rather important that the j ack should not be too heavy,

' but `yet should be apable of lowering the larger cars with ease and dispatch, preferably without manipulating the lever which raises the car. Y

ln the drawings: Figure 1 is a side elevation. Figure 2 -is a longitudinal Figure 3 is a plan view. Figure 4 is a transverse section Online 4`4 of Figure 3.

Figure 5 is a. longitudinal cross section on line 5 5 of Figure 3. Y

`Figure 6 is a plan view partly broken away cross section.-

of the connecting casting.

Figure 7 is a transverse view thru the axis of the saddle. f'

at the other end by the rear axle 15, which is secured in each of the rear brackets 16 by a-set screw 17, the brackets 16 each being permanently fastened to both the upper and the lower bars 10 and 1l respectively by means of rivets such as 18. Supported by the side bars 10 and 11 on each side are two'large castings 20 and 21, the former being for the tank and pump while the latter, the front casting 21 -forms the .cylinderin which the hydraulic piston or ram slides. The pump piston or plunger 22 is connected by a link 23 with a lever 24 pivoted to the shaft 25, the upper end of the lever forming an upright socket 27 to receive the tongue 28, which is fastened in the socket 27 by means ofthe usual binding bolt 29. The j ack is moved from place to place by means of the transverse grip bar or han'dle The main piston or ram 32 carries a wrist pin 30 fastened by a set screw 31. This wrist pin extends far beyond the'piston and projects between the top and bottom side bars 10 and 11 whereit is'pivoted at each side to the walking beams36 by means of links 38 each of which carries a lug 39 to which is sel cured a spring 40 attached at its free end to the frame, and tending to telescope the piston 32 into its cylinder 21. Y

The walking beams 36 are pivoted on the free ends of the upper shaft 40 which is mounted in brackets 42 which may be inte gral With'the casting 21. To these same brackets 42 are pivoted the drag links 44 having for their purpose the vertical positioning of the post 45 which carries at its top4 the usual saddle 46 to engage a load to be lifted.

In order to secure' rigidity of the walking beam structure it is found convenient to bolt the two beams 36 together by means of a rod es while for the support 50 in the walking beams 36, and also has a pair of shorter trunnions 52 serving as a ivotal connection for the drag links 44 so t at, since the pivots 40 and 53 are directly above one another, the pivots 51 and 52 will likewise remain one directly above the other in view of the parallel relation maintained by the bars, the vertical distance between the two pivots of each pair being the same. r v o The upper portion of the tank casting 20 formsan oil reservoir 54 closed at the top by a cover 55 which should be moderately strong for while there is normally no pressure in theoil chamber the oil from the ram c linder is discharged back to the reservoir un er a ressure de ndent upon the weight of the ve 'cle which as been lifted. The corners of the vreservoir chamber walls arefilleted as at 56r to .provide suilicient metal to receive thevv screws 57 andthewalls are also thickened `where nry as by the boss 58 for examle, lto sup rt the various connections. vThe ower longitudinal rib 59 is merely for additional strength and is naturally optional.

The bottom of the tank casting 20 is formed by an inte al member 60 in which there is a cylindrica bore 61 snugly receiving the pump iston or plungiir 22, being in fact the cylinso er thereof. ball valve 62'held in place by the sprin 63 admits oil through the ports 64 and 65, guring the suction stroke of the plunger, 'but closes communication between the main tank body or reservoir 54 and the 3s plunger cylinder bore 61 during the power stroke. As the handle 33 is moved downward and rearward the lever 24 and link 23 move theplunger 22 inward, driving oil through the assrage 66 in the casting 67 and past a 40 chec valve 68 to the horizontal passage 69 and into the chamber 70 of the forward cylinder 21. -The piston 32 is provided with acup washer 72 substantially oil tight, so that as oil is driven into the chamber 70 the ram will 45 more forwardly (i. e. toward the saddle 46) carrying with it the wrist pin 30 vand consefiliently swinging the walking beams '36 about 't eir 'pivots 40 so as to raise the saddle or load support 46.` 5o A foot pedal80 pivoted at 8 1 .controls a rod 82 pivotally connected to the foot 4pedal as at 83, which rod passes through a bore 85 in the tank casting 20, and its free end terminates just short of a guide block 87 5,15 mounted in the forward vwall of\-the tank castings20, the block -being held in proper position with respect to the check body, by the'lock nuts 88 and 89. 'A spring 90 en.

the front wall of thetank castiii A20- also a collar 92fthreaded-on the ro 82 8 eoan so as to hold this rod yieldingly in contact l with aratherfshortcylindrica needle valve 95, the conical point ofl which seats in a similarly tred bore 96 in the guide piece 87 body of the needle valve slides the tank casting;

Vpiece 87.

freely in the cylindrical bore 97 at the front end 98 -of the guide iece anfd is constantly in contact with the rod 82 except momentarily when the spring is compressed by the foot pedal80. y 7

A nipple 100, preferably communicating with the stuiling box oove, connects the rear end of the piston c amber 70 of the tank chamber by means of a pipe 102 connected to the tank chamber by means of an ordinary 75 union 104, and thev ni ple 105 threaded into Tis arrangement is to prevent loss of oil as -find it advantageous to provide some arrangement, for while the three ,o il ooves 108 a low but a veryslight. leakage, t ere is always some le y or withoutrin and this leaked oil way back to t e tank by way of the pipe 102, there being norestriction to rearward flow in this pipe (there is no pressure in the tank) andthe pressure behindv the ram therefore drives the oil back' to the tank since it is not possible to escape through the stuffing box 109 closing the'end of the pump cylinder in the usual manner. 1

The connecting casting or check bod 67 is connected to t e guide member 87 (w ich as shown has a bore completely through it b means of a short straight pipe 110 threa e into the guide piece @fas at 112, this means furnishing the return assage for the oil from the chamber 70. load on the saddle 46 or the pull of the spring 40 orboth tend to cause the iiston 32 to move forwardly, in case the nee 1e valve 65 is free to move, as when tthe pedal 80 is pushed rearwardly at the top, in which case the oil passes from the chamber 70through the passageway 69, the passageway114 in the outstanding lug of the casting 67, throughthe passage 115 in the pipe 110, into 1de 87, and finally .into the tank 20 throug the opening 117 in the guide Leakage through the stuing box is prevente by providing an annular groove 121 -in the forward en d of the cylindrical chamber 60 and having this groovecommunicate with the ,tank 20 by means of a small vertical passage 123. There is no tendency for oil to flow into the groove 121from the tank chamber as the plunger 22 is solid and its rearend never passes the groove. This leakage preventingmeans, nd the quite similai \means at the forwarr? end ofth raincylinder are important features of the nt invention they; insure against the untidiness almost invariably associated with hydraulicjacksrof all types. suitable for garage use. Y f

It b'etnote'd that the check body 67 is threaded into the tank casting 20 as at 130 v and is also threaded into the forward'or rain" cylinder 21 as at 131, hence it isnecessary to ils provide some manner of adjustably mounting 113 s into the casting 67 as at`111, and threaded 95 izo the guide block 87 with respect to the check body 67. The check bodyv is tapped as at 111 to receive one end of the pipe 110 and the guide block 87 is also tapped at 112 to receive the other end of this short pipein order to assemble the device, consequently the guide block 87 must be free to move with respect to the tank castin I therefore make the threaded rear portion of the check body87 smaller than the hole 133 in the boss 58 of the tank casting which receives it so as to provide a loose ht. When the other parts of the device are properly assembled and in permanent position the two lock nuts are brought to bear against opposite sides of the boss 58 in the tank casting so as to make an absolutely oil tight joint, packing 135 provided in the usual manner. The small longitudinal rib 136`is optional but it is very convenient to strengthen this small block, particularly in viewl of the vertical discharge orifice 117.

The operation of the device is as follows `The jack as a whole is pulled from place to place by means of the tongue 28 which is prevented from moving rearwardly, that is, in a direction toward the load support, by'a stop member 137 bolted on the link 23 in such position as to engage the pipe spacer 138 so as to insure that the plunger or solid piston 22 shall never be withdrawn from its cylinder. 'In such position the jack may conveniently be pushed forward into position under the car to be raised. If i-t is necessaryA to shift the rear wheels sideways lthis can readily be accomplished by lowering the handle'33 until the end of the plunger engages the threaded end 130 of the check body 67. With the parts in such position a slight further lowering of the handle 33 permits the forward end of the jack to be swung about the front ground wheels 140 as a pivot, raising the much larger ground wheels 141 slightly off the ground. When desired the saddle 46 may be raised with respect to its threaded sleeve 50 by revolving it in the usual and well-known manner within the limit of length of its post 45.5 c

When in exactly. the position desired, the handle 33 is reciprocated, on the upward stroke drawing oil from the reservoir 54 thru the vertical passage 64vand past the ball 62 which readily yields downward against the spring 63 so as to allow the oil to pass thru the horizontal transverse opening 65 leading tothe pump cylinder 61. On the downward stroke of the handle33 and postor tongue 28 the solid piston or plunger 22 moves rearwardly that is toward the load, until a con-- venient lowest position is reached or in case of a long stroke until the cup'washer 150 strikes the tapered threaded rear end of the check body .67. i

Attention might `be invited at this point tc the construction of this cup Washer 150 which is offelt or any other material usual for the purpose except that it is held in place by a single'screw 151, tapped into the solid end of the plunger, this construction Ibeing veryladvantageous and eliminating the necessity of finishing the working face of the pump plunger. The oil from the pump cylinder is discharged thru the passage 66, from thence upward past the ball 68 into the horizontal passage 69 which is preferably coaxial with the ram cylinder.

The oil behind-the ram 32 forces the latter toward the rear axle-215 and this movement swings the walking ,beams 36 about their pivoting shaft 40 by means of the transverse wrist pin 30 at the rear end of the ram. and

the two parallel links 38 which are pivot-ed to the walking beams at the lower ends of their short power arms while the load itself is carried at the free end of the longer load -carrying arms of the walking beams which load carrying arms are horizontal when they have moved roughly one third of their upward travel. The two'walking beams with their rigid cross connections 47-48-49'form a load carrying frame. Y

Should theram or the 'load support meet an obstacle beyond the strength of the jack 155 to the pipe 110, passage 115 in the guide block 87 and into the reservoir 541 thru the opening 117.

I find it desirable to make the capacity of the reservoir 54 just suficient to carry the load to the highest position desired, that is the cubic capacity of the reservoir shall 'exactly balance the cubic capacity of the chamber 70 at maximum movement of the ram plus the capacities of the various passageways. In case .it is preferred that the reservoir shall be able to hold an excess or reserve supply of oil some other means forlimiting the stroke of the ram must be provided so I have shown a positive stop at 158 which is engaged 1 by the wrist pin 30 ateach side-and thereby limits the movement of the ram on its working stroke. .l

To 'lower the load, the mechanic presses his foot against the upstanding lever 80` at the front of the truck and this withdraws the rod 82, compressing the spring 90 and allowing oil to pass from the ram cylinder 70 back to the reservoir 54 exactly as just described in connection with excess pressures. It should i be noted that theoperator can lower the load either very slightly or very slowly by pressmay take place in a very short period the action is always smooth even tho the pedal 80 is held to maximumy release position.l What I claim is 1. In a hydraulic jack having a ram, a ram `f cylinder, a pump, and a reservoir so connected that the pump draws fluid from the reservoir and forces it into said ram cylinder behind said ram, said reservoir having a lesscapacitythan the ram cylinder whereby the ram may not be driven out of` its cylinder by continual pumping. 2. In a hydraulic jack having a ram, a

Lacasse sageway between the ram and the reservoir,

a valve therein, adjustable resilient means i for closing the valve, and manually controlled means for releasing the valve from said resilient means to return fluid from the ram cylinder to the reservoir.

In testimony whereof I affix my signature.

' ROBERT E. MANLEY.

horizontal ram cylinder, a pump, and a reserv voir so connected that the pump draws fluid from the reservoir and forces it into said ram cylinder behind said ram, a stuiiing box cl`osf ing one end of the ram cylinder and forming an annular groove in said cylinder and a pipe extending outside of the cylinder for es-v tablishing free communication between said groove and said reservoir whereby fluid leakingaround the ram will be discharged through said ipe into the reservoir lwithout to the cylinder u tendenc to orce box pac Y 4 3. In a Jack, a wheeledtruck, a ram, a ram cylinder, a reservoir, a pump cylinder, a plunger therein, means connecting the pump cylinder with the ram cylinder and connecting the ram cylinder with the reservoir kand a spring pressedvalve normall closing communication between the ram cy inder and the reservoir but automatically releasable under excessive pressures.

4. The device of claim 3 in which manually operated means are provided for withdrawing the valve irrespective of pressure'.y

'5, lThe device of claim 3- plus yieldn means for holding the ram against the 'lui delivered intotheram cylinder by the ump, and manually controlled means opera. le at will to permlt said resilient means to empty lits way past the s tuing -the ram cylinder to lower the'jack.

6. In combination a reservolr-and' a-pump cylinder having three independent connectL ing passageways, one free, the second automatically discharging from the reservoir n suction stroke, and the third automatica ly operating from the cylinder to the reservoir upon excessive pres- 8. In a reservoir for a ram an sure in the c linder.

-7. 'The device ,of claim 6 in which the third passagewa may be manually Opened irrespective o pressure in the pump c linder.

check bod having a valved passageway therethru rom the pump to the ram, a pasv l Pump, a

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