US1880732A - Hydraulic jack - Google Patents

Description

Oct. 4, 1932. H. w. BOLENS HYDRAULIC JACK 2 Sheets-Sheet 1 Filed April 2, 1928 Oct. 4, 1932- H. w. BOLENS HYDRAULI C JACK 2 Sheets-Sheet 2 Filed April 2, 1928 INVENTOR.

A TTORNEY.

Patented oee 4, 1932 may w. non-ans, or mar wasrrmo'rox, vnsooram K HYDRAULIC JACK Application ma April 2,1988. Serial 10.288385.

This invention relates to an im rovement in hydraulic jacks especially, alt oughnot Along with this advantage the lifting mech- 1 anism is so. constructed and so organized with the jack as to have little or no overturning moment whereby the jack possesses a very high stability.

Another object of the invention resides 1n the provision of a hydraulic jack of thisv character of the type having hydraulically operable lifting mechanism and a handle connected thereto and carrying the pump for actuating the lift mechanism and wherein provision is made for preventing ingress of any appreciable quantity of the oil or other operating fluid employed into the handle and for draining from the handle any oil that may find its way thereinto.

Another object is to provide a hydraulic jack of this character having novel knockdown operating mechanism for the pump which multiplies the power applied to the pump and to the jack to facilitate the lifting of heavy objects such as heavy motor trucks or the like and yet is foldable into a compact space so as to be conveniently stored in the tool box of the vehicle, under a seat thereof, or in a similar place.

A further object of the invention is to provide a hydraulic jack having these advantages and capacities and which isof simple 'and durable construction, reliable and efiective in operation, and easy and comparatively inexpensive to manufacture. 46 Other objects and advantages reside in certain novel features of the construction, ar-

rangement and combination. of parts which will be hereinafter more fully described and particularly pointed out in the appended ,claims,and reference being had to the accompanying drawings forming a part of this specification, and-in which:

Figure 1 is a view in side elevation showing a hydraulic jack. constructed in accordance with the present invention;

Figure 2 is a fragmentary view in side elevation showing another type of handle and operating means that may be employed for the pump of the jack;

Figure 3 is a view in horizontal section taken on line 3-3 of Fi re 1;

Figure 4 is a detalview in section taken on line 4-4 of Figure 1;

Figure 5 is a view taken partly in section on line 5-5 of Figure 3, but having a num ber of the elements of the jack shown partly or wholly in elevation for the sake of simplicity in illustration;

Figure 6- is a detail view of the operating lever of Figure 1, the lever and associated 7 parts being shown in top plan;

Figure 7 is a view taken on line 7-7 of Figure 3, parts being broken away and parts being shown in elevation for the sake of simplicity in illustration, the handle in Figure :5 7 being swung up to a vertical-position;

Figure 8 is a somewhat enlarged view in transverse vertical section taken in the plane of line 88 of Figure 7; and

Figure 9 is a fragmentary detail sectional view similar to Figure 8 but showing a different position'of the parts to illustrate the action of the trip rod in unseating the valves and in blocking the opening in the mounting member. c

Referring to the drawings, it will be seen that a hydraulic jack embodying the present mventioncomprises a base 1 carryin the hydraulicall operable lift mechanism esignated genera ly at 2 and also a swivelled handle {5 clgntaming the pump 4 for operating the ac v I The hydraulically operable lift mechanism includes an inner or jack cylinder 5 having its lower. end threaded into a recess provided therefor in the base 1 as indicated at 6 -(see Figure 7). Surrounding the inner cylinder 5 andm spaced relation thereto is an outer or reservoir cyhnder 7 having its lower end bevelled and ground or machined to engage and box 14 provided in the head 9.

Lifting means is carried by the rod 13 of the piston 12 and may include a lift screw 15 engaged in a threaded socket 155 provided in the upper end of the piston rod (see Figure 5). The upper endof the lift screw is reduced and releasably secured as at 16 to a lifting shoe 17. While the shoe 17 may be taken off for purposes of assembly and disassembly preferably it is rigidly secured to the upper end of the screw 15 when the jack is in use. By turning this shoe 17 the screw 15' may be rotated-in its threadedbearing 15' and caused to project above the upper end of the piston rod 13 to the extent necessary for engaging relatively high objects. By turning the screw 15 to cause it to move down into the socket of the piston rod 13 the shoe 17 is appropriately lowered.

The lifting mechanism also includes an inverted U-shaped supporting bar designated generally, at 18. and having a body portion 19 and downwardly extending parallel legs 20 integral with the ends of the body portion 19 and located adjacent diametrically opposite portions of the cylinders 5 and 7. The lower end of the le 20 are connected by a rim 20" which sli ably embraces the cylinder and aids in maintaining the legs 20 parallel to the axis of the cylinder. The body portion 19 is formed with a central opemng 21 I counter-sunk around its lower end'as at 22 to receive and ,abut against the upper end of the piston rod 13. The screw 15 passes loosely through the openin 21. If desired, the bod portion 19 may appropriately fastene to the piston rod 13 but the interfitting abutting relation described and shown in Figures 5 and '7, together with the action of retractile coil sprin 2 3 with which the jack is provided is sufliclent to maintain these parts properly assembled. As illustrated in igures 1, 5 and 7, the springs 23 have their upper ends connected to pins 24 ri 'd with the body portion 19 and projecting literally therefrom. The lower ends: of the springs 23 are connected with apertured ears 25 integral withthe base 1. These springs are under tension when the piston 12 is in it's lowermost position in the cylinder '5 and so operate to forcethe body'portion 19 of the sup.- porting bar 18 down onto the piston rod 13.

he primary function of these springs, however, is to automa'ticall retract or lower the lifting mechanism an piston 12when the 1,aso,7aa

fluid below the iston is permitted to flow out from beneath t e same.

- Each leg 20 isprovided with a vertical 'series of teeth 26 and with a lengthwise shoulder or guide 27-behind the teeth 26 (see Figures 1 and 3). An adjustablelifting lug 28 is provided and has a portion 29 so shaped and serrated as to be adapted to engage the axle or other part of an automobile or other similar motor vehicle. This lug 28 is also provided with a pair of supporting fingers 30 and a pair of retaining hooks 31, there being one supporting finger-for each series of teeth 26 and one retainin hook for each shoulder 27. Each finger30 ears on a selected tooth 26 and each retaining hook 31 engagesa portion of its shoulder 27 adjacent the tooth 26 engaged by the finger 30. When a load is placed on the lug 28 the lug tends to rock on the fingers 30 engaged by the teeth 26 but this rocking tendency is counteracted by the hooks 31. A consideration of this action and an inspection of Figure 1 of the drawings will make it clear that the fingers 30 exert a lateral or horizontal thrust to the right, as viewed in Figure 1, while the hooks 31 exert a lateral or horizontal thrust toward the left in Figure 1. While the lug 28 may be supported in a horizontal position preferably it is designed tobe angled slightly upwardly and outwardly from the le' s 20 when it is supported on an of the test of the legs. The ug is locate entirely within the outline or confines of the base. In other words, a perpendicular dropped from the outer extremity of the lug would'intersect the base as will be understood from Figures 1 and 3. This is made possible by the construction whereby the lug partially embraces the cylinder and is engaged with supporting means located mid-way between the ends of the base. With the lug 28 so supported on the base the jack has a very low overturning moment and thus has marked stability so that even very heavy loads applied on the lug 29 do not tend to tilt or overturn the jack.

At one end of the base a pair of lugs designated at 35 and 36 isprovlded (see Figures 3, 8 and 9). On these In a swingable mountin member designate generally at 37 is swivel ed or ivoted for movement about a horizontal axis. This mounting member carries the pump,4 and the operating and member 37 therein and receiving theadjacent end portions of 1 trunnions' 40 and 41, respectively.- The trunnion 41 also has a portion received in a recess 42 provided in the lug 36 and suitable washers 43 are provided between the ends of the trunnion 41 and the re in which it is fitted. The trunnion 40 has a portion there of fitted for axial adjustment in an en- I ing 44 formed in the lug35. Axial ad ust- Iiient of the trunnion 40 is'efiectedby a foljusted position by means of a lock nut 49 threadedly connected withthe, lug 35 and. bearing against a washer 'interposed between the lock nut and the follower. With this construction the connectin member 1s swivelled on the jack base but t 1e swivelled connection may be sufliciently tight to hold.

the connection member against accidental displacement in any an lar adjustment and of course is entirely Oll tight.

The hand operated pump 4 (see Figures 7 and 8) comprises 'a pump barrel 52-the lower end of. which is threaded into the connectin g member 37 as indicated at. 53. A plunger 54 is operatively fitted in the barrel 52 and is carried at the lower end of a plunger rod 55. The pump is enclosed in a combined housing and tubular handle section 56 also threadedly connected with the member 37 as indicated at 57. The upper endof this housing section 56 is closed by a packing arrangement 58 through which the plunger rod is slidably fitted. Above the packing 58 the combined housing and handle is reduced and I consists ofa smaller tubular section 59, the

lower end of which has a releasable'threaded connection with a coupling member 60 threaded into the lower housing section 56. This housing so constituted serves to encase the pump and its controls and also provides a handle for regulating the angular position of the pump.- The upper end portion of the plunger rod 55 is always above the packing '58 and is threaded into a combined coupling and guide 61 which has a socket 62 receiving a ball 63 carried at the lower end of an operating rod 64, slidably fitted in and projecting exteriorly of a bearing 65 in the housing section 59. The coupling 61 it provided with an entrance slot 67 to its socket 62 to permit of the assembly and disassembly of the ball 63 therewith. With this construction when the section 59 is unthreaded from the coupling 60 and the socket member 61 pulled out beyond the coupling60 the operating rod 64 and the section 59 may be tilted over to the side and the ball 63 pulled out of the socket 62. I

The lower end of the pump barrel 52 freely communicates through a port 7 0' with an intermediate portion of a-transverse passage 71 extending through the connecting member 37 and communicating at one end with'a port 72 in the trunnion 41. The port 72 communicates through a thimble screen 73 with a passage 74 extendingaxially through the lug 36 and in open communication with an inclined, assage 75 extending at an angle through t e lug 36 and base 1 and terminating at the bottom of the s ace 75 between the cylinders 5 and 7 whic provides a reservoir for the oil or other operating fluid employed (see Figure 7). The reservoir 7 5 communicates through a passage 76 in the cylinder head 9 with the interior of the upper end of the cylinder 5 above the iston 12.

The other end of the passage 1 communi cates through a thimble screen 78 with a port 79 provided .in the trunnion 40 and communicating with an axial passage 80 in the follower 45. The passage 80 communicates through radial ports 81 with an external annular groove 82 formed in the periphery of the follower 45 and sufliciently wide to be in communication in any adjustment of the follower with a passage 83 extending through the lug 35 and the base 1 into the space in the cylinder 5 below the piston 12.

The communication between one end of the passage 71 and the reservoir 7 5" and the upper end of the cylinder 5 is controlled by an intake ball valve 85 coacting with a seat 86 provided in the passage 71, the ball valve being held against its seat by means of a spider 87 slidably fitted in the passage 71 and having a 71. -'A coil spring 90 is interposed between the spiders87 and 89 and forces the spider 87 against the ball valve 85 and in turn forces.

the ball valve 85 against its seat 86. The pin 88 terminates in slightly spaced relation to a discharge ball valve 91 which coacts with a seat provided therefor around the port 79 of the trunnion 40 to control communication between'the other end of the passage and the lower end of the cylinder 5. A coil spring 92 engages the valve 91 to hold it against its seat. v

To provide for the release or unseating of the valves 85 and 91, a trip rod 95 is'provided and has its lower end slidabl fitted in a longitudinal opening 96 forme in the connecting member 37, intersecting the passage 71 andlocated on the side of intake valve 85 remote from the pump 4 (see Figures 8 and 9) j The lower portion of this trip rod 95 is formed with a cam or inclined surface 97 positioned to en gage and unseat the ball valve 85 when the trip-rod 95 is raised. When the ball valve 85 is unseated, it displaces the spider 87 and the pin 88 to the left as viewed i in Figure 8 and such displacement of the pin 88 causes the pin to engage the ball valve 91 and displace it from its seat, as shown in Figure 9. '.Above the cam 97 the release bar has a notch or'recess 97 affording the clearance necessary to permit the valve 85 to seat when the trip'rod95 is in its lowermost-position. l

At its upper end, the trip rod 95 is rovided with a lateral extension 98 a rture to slidably receive the plu er ro 55. The juncture of the plunger r0 and plunger 54 presents a shoulder 99 which, when the plunger rod is raised to its extreme upper position, is engageable with the lateral extension 98 of the trip rod 95 to raise the tri rod and cause it to unseat the valves. Ordinarily the trip rod is held in its lowermost and inactive position by means of a coil spring 100 encircling the plunger rod 55 and engaging the packing 58 at one end and the lateral extension 98 at its other end. A sleeve 101 loosely embraces the plunger rod 55 and is interposed between the plunger rod and the lower portion of the spring 100 to prevent the spring from buckling. The upper end of this sleeve 101 is bevelled off as at.101 to facilitate the sliding of the sleeve past the convolutions of the spring.

As will be understood from Figures 8 and 9,

the lower portion of the trip rod completely obstructs or blocks the opening 96 when the trip rod is raised so as to prevent the oil from flowing up into the housin 56. This obviates any possibilit of the oil leaking out when the jack is store The trip rod is provided with a lon 'tudnal draining groove 94 which bridges t e wall of the opening 96 when the trip rod islowered and permits any oil that may have found its way into the housing 56 to drain back into the passage 71. There is no tendency for the oil to flow through the o nin v96 into the housing 56 except when t e va ves are tripped and the springs 23 or load on the jack are forcing the ack piston 12 downto move the oil quickly ack into the reservoir and at such time the lower end of the draining groove 94 is drawn up out of'the passage 71 and closed b the wall of the opening 96 while the note 97" is .still within the confines of the opening 96 and consequently the opening 96 is completely blocked as shown in Figure 9.

With this construction, when the plunger 54 is moved downwardly in the barrel 52, it forces the fluid, usually oil, down through the ports into the passage 71. The pressure of the fluid and the force of the s ring seats the valve 85but the pressure 0 the fluid unseats valve 91 to permit the fluid expelled b the pump to pass from the passage 71 throug the port 79, passage 80, port 81, groove 82,

' and. passage 83 into the lower end of the jack ing the piston 12 upwar of the plunger 54, the sprin 92 and the pressure combine to seat the va ve 91 but the succylinder 5 and beneath (piston 12, thus movly. On the upstroke tion induced. by the plunger 54 opens the valve 85 and draws the oil from the reservoir passage 71 past the valve 85 and up into the 'ump barrel through the port 70.

' v When it is desired to lower the piston, the

operating rod 64 is ulled outwardly as far as it will move there y actuating the tri rod 95 and unseating the valves 85 and 91 w ereupon the weight carried by the piston of the jack or the springs 23 or both operate to force the piston 12 down and to cause the After the piston 12 of the jack has been I elevated as far as it may be, continued opera-- tion of the pump will not resultin the buildin up of excessive pressures in the jack cylin der ,because of. the provision of a minute venting orifice in the inner cylinder 5 which permits theexcessive pressure to pass into the reservoir 7 5" and thence back to the pump.

To facilitate reciprocation of the operating rod 64 it may be provided with a transverse hand grip but where heavy loads are to be lifted'the operating means of Figure 1 is preferably employed and as shown consists of an operating lever 126 having one end bifurcated and fulcrumed as at 127 on a link 128 pivotally supported as at 129 in a slot formed at the outer end of a laterally extending lug 130 integral with a head or collar 131 replacing the guide 65 and shrunk or otherwise secured in the upper end of the handle section 59 and having an axial opening through which the operating rod 64 slidably extends. The lever 126 is pivotally connected to the outer end of the rod 64 by means of a removable pivot pin 132 extending throu h transverse pivot openings provided in t e lever and in the rod 64 and held against accidental displacement by a cotter pin 133. This arrangement permits the operating lever to be readily disconnected from the rod 64 and .folded with its link up against the handle section 59 when the jackis knocked down, as illustrated in dotted lines in Figure 1. To secure the parts in folded position a spring clip 134 is mounted on the handle section 59 and has its spring jaws designed to embrace and hold the lever 126, as illustrated in Figure 4. This is of especial advantage in connection with the character of combined handle and housing used whose sections may be disconnectedto permit the jackto be made into a compact bundle and-stored in the tool box, or under the seat, or the like.

The invention claimed is:

1. A hydraulic jack comprising hydraulically operable lift mechanism, a mounting member connected thereto, a pump carried by the mounting member, there being passages in the mounting member leading from the pump to the hydraulically operable lift mechanism, valve means in said passages constraining the pump, when operated, to elevate the hydraulically operable lift mecha- 65 ture.

nism, a trip cooperable with said valve means to permit the hydraulically operable lift mec anism to lower, a casing for the trip and pump, said mounting member having an openingthrough which the trip extends, said trip completely obstructing said opening when positioned to trip the valves, said trip having a drain groove bridging the wall of said openin when the trip is in inoperative position an blocked by the wall of the openmg when the trip is in operative position.

2. A hydraulic jack comprising a hydraulically operable lift mechanism, a mounting member connected thereto, a pump carried by 5 the mounting member, there being passages in the mounting member leading from the pump to the hydraulically operable lift mechanism, intake'and dischargecheck valves in -said passages forcausing the pump when '20 operated to elevate the hydraulically oper able lift mechanism, said mounting member having an opening on the side of the intake check valve remote from the pump, a trip for the valves extending through said opening,

a casing for the pump and trip carried by the mounting member, said trip being effective to close said opening when in position to trip the valves and permitting draining of the casing when in inoperative posi- 0 tion.

3. A knock-down operating mechanism for use in swinging a swingably mounted pump of a hydraulic jack and reciprocating the plunger rod thereof and comprising a tubular handle connected to the pump and having a detachable outer section, an operating element for the pump movable through the handle, a detachable connection between the operating element and the plunger rod releasable, only when the sections of the-handles' are detached, an operating lever fulcrumed on the detachable handle section, a releasable connection between the operating lever and the operating element, said operating lever being foldable up against the handle when disconnected from the operating element, and means for releasably securing the operating lever folded against the handle.

4. A knock-down operating mechanism for reciprocating the plunger rod of the pump of a hydraulic jack and comprising a handle, an operating element for the pump associated with the handle, a link pivotally supported on the handle and pivotally connected to the operating lever to provide a fulcrum therefor, a releasable connection between the operating lever and the operating element whereby said operating lever may be folded up against the handle when disconnected from the operating element, and means for releasably securing the operating element folded up against the'handle.

In witness whereof, I hereto afiix my signaiHARRY w. BoLEN's;

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