US2393410A

US2393410A - Hollow hydraulic jack

Info

Publication number: US2393410A
Application number: US459256A
Authority: US
Inventors: William S Pine
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-09-22
Filing date: 1942-09-22
Publication date: 1946-01-22
Anticipated expiration: 1963-01-22

Description

W. S. PINE I Jan. 22, 1946.

HoLLow HYDRAULIC JACK Filed sept. 22 1942 Patented Jan.f22, 1946 UNITED STATES PATENT OFFICE v HOLLOW HYDRAULIC JACK William S.`Pine, Southgate, Calif.

Application September 22, 1942, Serial No; 459,256

I (Cl. 30g-.34)

2 Claims.

My invention relates to a hydraulic jack and particularly to a jack of this class for drawing two or more members relative to each other.r

An important object oi' this invention is 'to provide a simple and eillcient hydraulic jack which will serve as an ordinary jack for raising objects above and also upwardly from below the Jack; and which will also serve for drawing two or more members together, or for withdrawing A further object of this invention is to provide I simple and efcient means for transferring the liquid from the reservoir'into the compresison chamber. l

An important object of this invention, also, is

to provide a novel and efilcient method of constructing and finishing. the adjacent surfaces of two concentric cylinders for a jack of this class. and in which there is provided a narrow annular cylindrical spaceA of 'considerable depth therebetween.

' A further important object of this invention is to provide novel, simple and economical means A of variously sealing the'liquidof the hydraulic jack against escape.y and toV provide especially tight joints between mutually reciprocating cylindricalparts to withstand unusually high fluid pressure, and provide novel and effective means-v of securing the sealing means in place.

- With these and other objects in view, as will appear hereinafter, I havedevised` a hydraulic jack of this class having certain novel features of construction, combination and arrangement Fig. 3 is a sectional elevation thereof taken through-3 3 of Fig. l;

Fig. 4 is an enlarged'fragmentary sectional view showing the sealing means between the plunger and the cap of the cylinder;

Fig. 5 is an other enlarged fragmentary slightly exploded sectional vview showing particularly the means for forcing the sealing leather against thewall of a relatively movable member; and

Fig. 6 is an end view of the head of the pump plunger taken through 6 3 of Fig. 3.

The enclosing housing of my hydraulic 'jack consists of an outer cylinder I, an inner concentric cylinder 2, and a thick head 3 connecting the lower ends of said cylinders, which head v forms the base of the jack. The space between the cylinders I and 2 provides a relatively narrow annular compartment or annular cylindricalv space A into which extends the lower portion of the moving or extensible member of my jack, which is the plunger. This moving member consists oi an annular piston 4 which has at its radially inner portion an upwardly extending tubular piston rod or shank 5. The upper end of the tubular piston rod portion has an axial opening 5* which is smaller in diameter than the main portion of the piston rod, forming a shoulder 5b which is adapted to engage the upper end .of t e inner cylinder 2 for limiting the lower posi ion of the piston. The diameter of the opening I5* is substantially the same as the inside The upper.

diaineter of the inner cylinder 2.` en/d of the space between the outer cylinder I and the tubular piston rod is enclosed by a cap 6;' which is screwed over the upper end of the outer cylinder. The main enclosure member of my jack, con- `sisting of the cylinders I and 2 and the base 3, is f made by forming the cylinder I and the base 3 as one member, machining the inner cylindrical wall of the cylinder I, machining the exterior surface of a tubular member to form the cylinder 2,

of parts and portions, as will be hereinafter described in detail, and particularly set forth in the appended claims, reference being had to the ac.

companying-.drawlng and to the characters ofy reference thereon, which form a part of this application, in which:

Fig. l is a top view of my hydraulic jack in" a I preferred form, portions thereof being broken away to facilitate the illustration;

Fig. 2 is a fragmentary side elevation thereof, also showing portions broken away and in section, the sectional portion being taken through 2--2 o! Fig. l;

and then welding or otherwise securing the lower end of the cylinder 2 into a corresponding hole in the base 3, as indicated by B in Fig. 3.

The piston rod 5 and the piston 4 fit loosely in the space A, and the tubular piston rod extends loosely through the axial portion of the cap 6. There'are, however, provided means in connection with the piston and cylinders, means for A sealingthe respective joints between said members.

At the lower end or face of the piston is secured a sealing leather 1 which is of inverted U-shaped cross-section, the outer leg or flange 1a engaging 2 I f aaeauo the inner wall of the outer cylinder while the inner leg or flange 1b engages the outer surface of the inner cylinder. This sealing leather is secured in place by an annular retaining ring or plate 8 located within the hollow portion ofthe sealing leather, the annular retaining ring being secured to the lower face of the piston by screws 9.

In a cupped sealing leather of this type, the outer flange Ia normally engages tightly the inner surface of the outer cylinder. I have provided, however, a flexible and elastic vannular member I which is seated lwithin an annular groove 8a, this groove being provided in the bore of the retaining member. The central opening of the'flexible member I0 is bevelled at the upper portion and this bevelled portion engages the correspondingly bevelled lower edge of the cup or sealing leather 1. As the retaining member 8 is clamped in position, the elastic member I0 forces the inner flange of the cup leather against the outer face of the inner cylinder 2v designated A2, is the reservoir for the liquid formotivating the jack. In the cap 6 is provided a sealing ring Il for preventing escape ofthe liquid from the reservoir A2, particularly when' cross-section, the outer leg II being positioned at the bottom of a groove Ba, in the wall of the; bore of the cap, and the outer side of the other leg I Ib being positioned in engagement with the outer cylindrical surface `of the-piston rod 5. The inner leg I Ib terminates ina feather edge and is resiliently forcedi'a'gainst the piston rod, the dotted lines. in Fig'. iindlcati'ngthe normal shape of the innerleg.' of .the sealing ring before engaging thepiston rod. 1

The fluid of my jack is transferred from the reservoir A2 into the compression chamber A1 by a` pump mechanism placed preferably at the side of the outer cylinder I. This pumip mechanism consists essentially of a cylinder 2| and a plunger 22. The cylinder is shown as screwed at its lower end into a fitting 23 and the fitting 23 isV secured at its lower end in a threaded recess 24a of va base 24 secured' to and forming substantially a lateral extension of the base 3 of the jack. At the upper end of and around the plunger 22 is provided a stuffing box 25. The plunger is provided with an enlarged bifurcated head 22a which is 24b on the base 24.

At the exterior of the outer cylinder is provided a conduit 28 which may be made as a. part of the outer cylinder I. This conduit is connected at upper portion of the reservoir.

of the conduit 28 is connected by means'of a 70 transverse port 24c with tan;` annular channel at the lower and peripheral portionofthe threaded plug of the fittingv 23, the channel vbeing formed by a groove .2'3a at theglower end of the fitting. The fitting' 23 is providedwith two longitudinal 59 .engaging'the cap Banditliespiston 4.-

passages 2lb and'swgztheiormer'being positionedk at the side of the fittingandex'ndingffrom said annular channel to the upper end of tlrez-ttl'ns or to thev threaded recess receiving the lower end 5 of the cylinder 2i the other .passage 23 extends to pass into the cylinder 2l and the latter preventing a return of fiuid into the cylinder. The lower end of the passage 23c communicateswith a transverse passage 3 which communicates with the lower end of the annular compression chamber A1 through a port in the base 3. In this manner fluid is forceably transferred from the reservoir to the compression chamber.

The interior of the outer cylinder I is also connected with the conduit 28 by means of a small by-pass orifice 28", this orifice being positioned below thev port 28EL so as to prevent the lower end of the sealing leather 'I to be forced outwardly beyond the orice 28.

At the juncture ofthe conduit 28 and the horizontal passage 24 is provided a thimble screen 3l which may be inserted through 'an opening normally closed by a plug 32. At the lower end of vthe intake passage 23b is also provided a screen 30 In order to relieve the pressure within the compression chamber A1 and allow the liquid again to be transferred to the reservoir A, I have provided a release valve whichconsists of a ball 4I and arelease jscrew- 42. Theball 4I, when it is desiredztd'prevent the lreturn,offluid, is seated the jack is used in any other than an upright` Y position. This ring is also of inverted U-shaped viiends; inagibilit# isgrconnected with the annularlpa'ssage/ppwided 'by the channel 23a by means of an angularport 24f, as shown in Fig. 1. Thus, the liquidfin the `compression chamber of the jack-is returned tothe vvreservoir through the i c' r1; 'zs\-.-

- Tofacilitate `the return-,ofi'thei-pifston to its =lowered position, I have `provided -a 'compression coil spring ll within ,the reservoiry A, its ends ,usages-3, 24d,`24, 241, 23, 24e, yconduit 28 and vjackyis .constructed fora-drawing two memv` bers ltogfetlier, lor-forzraising objects from below i j For this reason, theinslde diameter rcylinder is relatively large, and the u al .o p ning 5, atthe upper end of the piston rod, iscorrespondingly large, To raise an ob- ',ject from below thejack, a rod 6i may be placed 'through .the axial' portion of the jack and the 'upper endmay be supported by a supporting disc a ,162, or ltheilike, on the -upper end of the piston rod, pivotally connected to the intermediate portion of an operating lever 26. The end of the operating lever is pivotally connected bya link 21 to a boss asshown in Fig. 3.

'I'hough I have shown and described a particular construction, combination and arrangement of parts and portions, I do not wish to bey limited to the same, but desire to include in the scope of my invention the construction, combination, and arrangement substantially as set forth in the ap pended claims'.l

, v,I claim:

1. A- machine of the class described, a. cylinder, a piston reciprocally mounted therein, a sealing leather member having a flange positioned against the face of the piston head and a second fiange engaging the cylinder wall, the edge oi the second flange being bevelled towards the first flange, an annular plate securing the rst ange to the piston, said plate' being provided in its side wall with an annular groove, and a flexible annular member mounted with a portion in the groove and extending with its other beyond the plate, the outer portionof the flexible member' being bevelled and"engaging the bevelled outer edge of the second flange for forcing said flange against the wall of the cylinder, said flexible annular member being positioned radially outwardly from the second `flange for resiliently contracting the diameter of the second flange around the wall of the cylinder. Y

2. A machine of the classdescribed, a cylinder,

a piston reciprocally mounted therein, a sealing 15 leather member having a flange positioned against the face of the piston head and a second flange engaging the cylinder wall, the edge-of the second flange being bevelled towards the rst flange, an annular plate securing the first flange to the piston, said plate being provided in its side wall with an annular groove, and an elastic annular member mounted with a portion in the groove and extending with its other portion beyond the plate, the outer portion of the elastic member being bevelled and engaging the bevelled outer edge of the second flange for forcing said flange against the wall of the cylinder, said elastic annular member being positioned radially outwardly from thesecondflange for resiliently contract ing the diameter of the sec'ond flange around the wall of the cylinder.