US2503478A - Hydraulic jack construction - Google Patents

Description

April 11, 1950 E. P. GRIME 2,503,478

HYDRAULIC JACK CONSTRUCTION Filed July 9, 1945 dim-05:5

latented Apr. 11, 1950 UNITED STATES PATENT OFFICE HYDRAULIC JACK CONSTRUCTION Edward P. Grime, Los Angeles, Calif.

Application July 9, 1945, Serial No. 603,905

2 Claims.

My invention relates to hydraulic jack constructions. The objects of my invention are:

First, to provide a jack construction employing hydraulic force to efiect its operation, and wherein the jack pump is encased in and protected by the hydraulic fluid reservoir.

Second, to provide a jack construction of this character, wherein a particularly simple yet effective means is provided to vent the hydraulic fluid reservoir as fluid is moved into and out of the reservoir.

Third, to provide a jack construction which employs the pump unit itself as a tension bolt for holding the parts of the reservoir together so that the entire structure is particularly simple and compact.

Fourth, to provide a jack construction which incorporates a novel handle device for actuating its pump unit, the handle device also serving as a pry tool to facilitate removal of railroad axle bearings.

Fifth, to provide a jack construction which has wide range of application, but is particularly suitable to facilitate the removal and servicing of railroad car axle bearings.

With the above and other objects in view as may appear hereinafter, reference is directed to the accompanying drawings in which:

Fig. 1 is a partial elevational, partial sectional view of my jack construction.

Fig. 2 is a fragmentary and idealized sectional view of a railroad car axle bearing and adjacent parts illustrating the manner in which my jack and handle device are employed.

Fig. 3 is an elevational view of the combined handle device and pry tool.

Fig. 4 is a fragmentary section of the sectional view of the reservoir cover, showing a modified vent means.

My jack construction is mounted on a base I, preferably a casting. The base is provided with an upwardly directed annular boss 2 which defines the lower end of the reservoir for the hydraulic fluid.

Within the reservoir boss 2 is an upwardly directed integral boss which forms a pump housing 3. The pump housing is provided with a threaded socket l which is concentric with respect to the reservoir boss 2. Seated in the lower end of the socket 4 is a valve block 5. The valve block is in the form of a cylinder preferably spaced slightly from the walls of the socket 4 and provided with an intake valve 6 and a discharge valve I and associated passages.

The passage for the discharge valve 1 extends axially from the upper to the lower end of the valve block and communicates with a recess 8 formed in the bottom of the socket 4. The recess 8 communicates With a discharge passage 9 extending through the base I and communicating with the jack cylinder to be described hereinafter.

The passage for the intake valve 6 communicates between the upper side of the valve block 5 and a side wall thereof. Suitable ports I!) communicate between the socket 4 and the exterior of the pump housing but within the reservoir boss 2.

A bypass II is provided between the recess 8 and the ports or supply passages I0. The bypass II is controlled by a relief valve I2 preferably comprising a ball check valve and a suitable locking pin, the latter extending through a packing gland I3 so that the relief valve may be locked closed or permitted to open.

A pump cylinder I4 is screwthreaded into the socket 4 and seats against the upper end of the valve block 5 so that the valve block in turn seats against the base of the socket 4. The pump cylinder I4 is provided with a bore communicating with the intake valve 6 and discharge valve I. The upper end of the pump cylinder :4 is likewise threaded and receives a flanged collar IS. A cylindrical shell H3 seats on the reservoir boss 2 and is provided with a cover ll. The flange of the collar I5 is adapted to bear against the cover [7 to secure the parts of the reservoir in place so that the pump cylinder I4 and collar I5 form in efiect a tension bolt.

The pump cylinder I4 is equipped with a piston I8 and piston rod I9. The rod I9 extends upwardly through the collar I5 and is surrounded by packing 20 and a packing nut 2 I. The packing nut extends to at least a point slightly below the under side of the cover IT. A small vent opening 22 is provided in the collar I5 immediately under the cover ll, the vent opening being covered by the threads of the packing nut. The threaded connection between the packing nut and collar has sufficient clearance that a labyrinth passage is formed between the interior and exterior of the reservoir so that air may move into the reservoir as the fluid is pumped therefrom and air is permitted to escape from the reservoir as fluid returns. At the same time, no appreciable loss of hydraulic fluid occurs.

The extended end of the piston rod I9 is provided with a yoke 23 which is pivotally secured to a lever 24. One end of the lever is connected by a link 25 to a bracket 26 provided on the 3 cover H. The other end of the lever 24 is adapted to receive a handle device 21.

The handle device 2'! comprises a tubular portion 28 and a pry member 29 at its extended end. The handle device not only serves to work the pump unit, but also serves as a prying tool to facilitate the removal of the railroad car axle journal or associated parts when the jack is employed to service railroad car journal boxes shown in ig. 2.

A jack cylinder 30 is welded or otherwise secured to the base I and extends upwardly therefrom alongside the reservoir. The jack cylinder 30 is provided with a piston 3| on which is mounted a stem or ram 32 which projects from the upper end of the jack cylinder. The jack cylinder is provided with a collar 33 which forms a guide for the ram, and shoulders 34 and 35 :are provided by the collar 33 and ram 32 respectively to limit upward movement thereof.

The ram 32 is preferably provided with external threads 36 occupying the portion of the ram which .protrudes from the jack cylinder. A lock nut -31 is employed which screwthreads freely on the ram and is employed to secure the ram in any extended position, so that in the event that the hydraulic pressure under the ram should fail or reduce in value, the ram will not settle back into the jack cylinder and lower the load which it is supporting.

With reference to Fig. 4, a separate vent means may be employed in place of the vent 22. This construction is particularly desirable if there is danger that the pump may occupy an inverted or tipped position for any length of time. The modified vent construction comprises a fitting 4| having a bore, the outer end of which'is threaded to receive a'knurl headed screw 42. The threaded shank of the screw 42, is provided with a longitudinal-bleeder43. Below the screw 42, the fitting 41 is provided with a porous plug 44 of packing material, located between perforated washers '45.

My jack has particular application in the servicingof railroad car journal boxes. In such use my jack is employed as follows: The jack is positioned so that the ram when raised, will engage the under side of the journal box A so that the journal box may be raised while the axle B remains supported by the car wheel C on the rail D. The journal bearing E which is in the form 'of a semi-cylindrical block, is then capable of being removed. This removal is facilitated by use of the pry member 29 which is inserted into a slot provided for the purpose in the bearing.

This jack ram is raised by operation of the pump unit, and is lowered by opening the relief valve 12.

It should be understood that while the particular embodiment of my jack shown in the drawings is adapted to the servicing of railroad car journal boxes, that the reservoir and pump arrangement wherein the reservoir forms a protective means for the pump and the pump in turn forms a tension element to hold the parts of the reservoir together, may be employed in associa tion with many types of jacks. In this regard, it should be noted that the pump with its reservoir and the hydraulic jack piston and cylinder, may be mounted on separate bases rather than on a commonbase.

Many other embodiments of the invention may be resorted to without departing from the spirit of the invention.

I claim:

1. A jack construction, comprising: a reservoir structure; a pump unit extending from end to end thereof and protected thereby said pump unit including a flow passage communicating with said reservoir a piston rod for said pump unit protruding from said reservoir; means for actuating said piston rod; a packing gland for said piston rod and incorporated in said pump unit, said packing gland including a threaded packing collar extending through an end of said reservoir structure; said pump unit having a vent opening in the interior of said reservoir structure communicating with the threads of said packing collar whereby said threads form a labyrinth passage for ingress and egress of air as said reservoir is emptied and filled with liquid.

2. A construction as set forth in claim 1 wherein said reservoir structure includes end and side members and said pump unit constitutes a tension element for securing the members of the reservoir structure together.

EDWARD P. GRIME.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 974,988 Northam Nov. 8, 1910 1,610,499 Dybens Dec. 14, 1926 1,667,759 White May 1, 1928 1,715,901 Countryman June 4, 1929 2,091,729 Countryman Aug. 31, 1937 2,283,593 Akins May 19, 1942

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