US2415684A - Jack and jiggle jack - Google Patents

Description

Feb. 11,1941 AR iER 2,4155% JACK AND JIGGLE JACK Filed April 8, 1945 ,7 Sheets-Sheet l IHHIIIIIHII M. GARANCHER JACKJWD JIGGLE'JACK I Filed April s, 1943 Feb. 11, 1947.

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JACK AND JIGGLE JACK Filed April 8, 1943 v 7 Sheets-Sheet 5 Feb. 11, 1947. R 2,415,684

JACK AND JIGGLE JACK Filed April 8, 1945' 7 Sheets-Sheet 7 7/1651 gwpajnfilr 1 W, W 6% Patented Feb. 11, 1947 JACK AND JIGGLE JACK Marcel Garancher, Chicago, 111., assignor to Stewart-Warner Corporation, Chicago, Ill., a corporation of Virginia Application April 8, 1943, Serial No. 482,242

9 Claims.

This invention relates to an air operated jack and jiggle jack for use with vehicles.

One object of this invention is to provide a jack which will collapse to small dimensions and which can be used wherever air pressure is available for lifting the vehicle, or a part thereof, and holding it in its lifted position, or for lifting and lowering the chassis of the vehicle repeatedly and automatically for the purpose of freeing up the spring shackle bearings and for assisting in working grease into such bearings.

Another object of my invention is to provide a jack which can be readily adjusted by hand to a position to contact with the part of the vehicle to be lifted and thereafter be operated by air pressure to raise and lower the vehicle part with which the jack has been connected.

: Another object of my invention is to provide means for causing the jack to jiggle with a stroke less than that of which the jack is capable when used only for hoisting.

Another object of my invention is to provide a jack'in which the movable parts are suitably protected against dirt which frequently falls upon the jack from the vehicle.

Still other objects and features of my invention will appear from the following specification and drawings, in which like parts are designated by like characters throughout the several views.

My invention is illustrated in the accompanying drawings, in which Fig. 1 is a plan view of the top of the jack;

Fig. 2 is a vertical sectional view showing the jack in its fully collapsed condition;

Fig. 3 is a fragmentary section taken on the line 33 of Fig. 1;

Fig. 4 is a vertical sectional view showing the two jack extension members adjusted into their raised positions;

Fig. 5 is a horizontal sectional view taken on the line 55 of Fi 2;

Fig. 6 is a horizontal section taken on the line |i6 of Fig. 2;

Fig. '7 is a horizontal section taken on the line of Fig. 2;

Fig. 8 is a horizontal section taken on the line 88 of Fig. 2;

Fig. 9 is a horizontal section taken on the line 9-9 of Fig. 2;

v Fig. 10 is an enlarged fragmentary vertical section taken through the center of the valve mechanism for the jack;

Fig. 11 is a horizontal section taken on the line of Fig. 2;

Fig. 12 is a vertical section taken on the line |2|2 of Figs. 10 and 11;

Fig. 13 is a vertical section taken on the line |3--|3 of Fig. 10;

Fig. 14 is a horizontal section taken on the line |4-|4 of Fig. 10;

Fig. 15 is a vertical section taken on the line |5|5 of Fig. 10;

Fig. 16 is a horizontal section taken on the line Iii-l6 of Fig. 10; and

Fig. 1'7 is a fragmentary vertical section of the 'jackshowing the slide valve in the position in drical housing 2| at the top of which a guide ring 22 is mounted and held in place partly within and partly upon the upper end of the cylindri- Cal ho si 2| by means of a pair of arcuate clamps 24 and 25 drawn together about the periphery of the cylinder 2| and guide ring '22 by means of bolts 26 and 21. The cylindrical housing 2| is provided with a groove 29 near its upper end, into which correspondingly shaped portions of .the clamps 24 and 25 project, and the guide ring 22 is provided with a shoulder 30, above which portions of the clamp members 24 and 25 abut, thus holding the guide ring 22 and the cylindrical housing 2| firmly together against a very high pressure, which may be applied to the under side of the ring when the jack is in its uppermost position under the influence of high air pressure. A partition 3| extends across the cylinder 2 I and is suitably welded in place to form the lower cylinder head.

The piston for raising the jack comprises a circular disc 33, an abutting cup washer 34, a spring cup washer expander 35 and a cup shaped metallic protector and stop member 36, all held together by means of a hollow nut 31 threaded into the central opening through the plate 33 and having a shoulder 38 which clamps the metallic cup member 36, the sprin expander 35 and the cup washer 34 firmly together in the order named on the bottom of the circular piston disc 33.

A cylindrical piston rod 40 of a diameter to provide a working fit within the guide ring 22 is secured by means of a plurality of screws 4| to the upper face of the circular piston disc 33, the diameter of the piston rod 40 being somewhat less. than the internal diameter of the cylindrical housing 2!. Suitably welded, or otherwise 35 and 35.

. A ring 46 is secured within the upper end of,

the cylindrical piston rod 49 by a press fit against a shoulder 41 formed on the inner wall 'ofthe cylindrical piston rod 40. The opening through ring 46 has a greater diameter inone direction than it has in the direction at'90 degrees'thereto'; as shown in Fig. 9.

Extending through the opening? in the ri'ngf lliis a lifting member 48 having wings 49 and 59 registering with the elongated portions of the opening through the ring 46. The lifting memh'r 48 is i'n ole-rein 'o'fa slel/E the-ifoot-"M-of which rests upon the upper surface- 6f; the-piston plate 33.- The= foot*of-' the-sleeve 48 'is enlarged to the diameter of the inside of the cylindrical piston 'rdd iil. The-sleeve 4 8fisalso provided with a second set of wings 52 and '53,-sh"owrrin cross seenen' in Fig. 8; and looated subst'antially'mid way between the upper pair of wings 49 and 50 and the'fdottl "attire-bottom'ofthe sleeve 48.

The upper portion of the lifting-sleeve 48 1s internally threaded at 55 to receive a screw-56 carrying altits top-e rvolvable sn'o'e- 58- having a uewnw erdi projecting" stem 59 rotat ably mounted-within the cylindrica interior of the screw 56. The shore 58 is provided with a plurality; preferably four, of sm'all projectiohs 60 to prvnt "th'e'sho'e from slipping: olT ofa pertihnbf "a vehicle against" which it is pressin for crapper-jigging purposes. The stem 59 is'pr'ev'nted' from making acomplete revollition within "the 'screw- 55 by rrians off a" set screw 6! extends into a groove tz (Fig. 5) which is chi; only part way aroufid-tliestem '59. A ball as is pressed by a s ri g 61 againstthe inner serraee ofthe cylindrical screwifi 't'oprevnt a too ready-rotational movement of the stem 'li9 within thescrwifi.

A "metallic disc 69 (Fig. 6) is p'rovided with a toiigueflil extendmg irito'a'keyway H cut lengthwispf the lifting sleeve-4a. The periphery of the rri'et'allic disc '69 rests Io'oslyupon a shoulder l2g formed 'at thetop' of the inner 'wallfofithe cylindrical piston rod lil; the'metallicidisc '69-'be= irrgirot'atablelwith 'the lifting sleeve- 48 and rotatablewith'in" the cylindrical piston rod 405 An operator desiring to" place theiack under apart to be lifted rotates the shoe 58 by means of the projections-ffiile-thus raising the screw 56 within the'lifting'sleeve18 until thersl'ioe'fifi contacts the 'part' of the vehicle to be raised, or else until the'screw 560011'1'83 toth'e end of its movement. If at this time the'-shoe-58' is still a considerable distance' below the partof'the ve hicle on: which the raising-force is to be applied, theshoe"58 is'lifted byi han'du'ntil either the upper pairof wings and 50 is :raised above the upper surface of the ring 48, or if this is not high enough, then-until the lower pair of wings 52 and 53 is raised above the upper surface of the ring 46.

At on'e' of the two before" mentioned ralse'd p'ositions of the liftin sleeve 48'th'e operator rotates tlie sleeve 48through90 degrees to permit oneof the setSOf wings; eithr lflarid 50" 01*52 and 53,110 rest in depressrenssaer the same shape 4 as the wings formed in the opposite solid portions of the ring 46. The piston is now raised by the application of compressed air between the cup washer 34 and the cylinder head 3!, the lifting sleeve 48 being raised either by reason of the fact that its foot 5| rests upon the upper surface of the piston disc 33, or; by reason of the fact that one or the other of itspairs of wings 49 and 5B, or 52 and 53, rests upon the .solid portions of the rin 48, which rises with the piston rod 40.

V In all of the various positions of elevation of the parts of the jack the screw 55 is held in axial alignment with the cylinder 2i by the threads 15;,

"in axial alignment with the cylinder 2| by its in the li'fti'rig 'sle'v'e48. The lifting sleeve is held circumferential foot 5!, and by the close fit of its upper portion within the opening through the ring i'fi; The piston rod is held in axial alignment with the cylinder 2| by means of the cupped plate 33; which contacts "the inner wall or the cylinder 2| at a low I point, and the" guide ring 22,- which coiitactsthe' piston rod 40 at a point always=somewhat remote-from the'point of contactof-themetalliccuptfi within the cylinder wall;

Provision in: the form of'on'e'or more grease nipples 1'3 communicating with a: circumferential' gre'ase passage 74 on the inner surface-of the guide ring 22 facilitates lubrication of the working surfaces of the guide'ring 22 and'the cylindrical piston'rod' lfll The' lifting stroke of thej'ack is the distance between the'upper surface of theoircularplate- 33 andth'e lower surface of the" guide ring'22} Because-mypneuznatic jackds arranged'forautomatic operation toraiseahd lower'the vehicle periodically, or'fo'rmanu'al operation toraise and lower the Vehicle at will, certain valve mechanisms are provi'ded fora'dmittingand relieving the air in accordance with the' desired operation.

Thaauto'matic valve mechanism as shownin Figs. I0, '11,:l-21andv1-7 comprises a; mechanism to be-here'inafter'fully described for moving a slide valve member 'l'i from/its lower position, shown in Fig.'10, to its upper-position; shown in'Fig. 17. This slidevalve member if includes a rectangular block with a; depression 18 milled into one side for completing or cutting err communicationbetween the passageways '19 and '86 drilled: through the polished faced, generally cylindricalplug 9|. The opposite sideof 'the'slide' valvem'ember 11' is provided with a-milled slot 82 out with" the axisof the miller in 'a pla'ne' at right angles tothe plane of theaxis of theunill'er with which-the depression 18 is cut. The purpose of the'depress'ionfl is-to forman' abutment against a circumferential ridge lit-formed between two circumferential: valleys 85 and 86 in the reciprocable operating'sleeve 88 (Figs. 11 and-:12) to'prevent-the'valve block' H from moving laterally across operating sleeve-88. Balls:89-and"90-pressed' into -thevalleys BE-or 86 by springs 92 and 93 serve to holdthereciprocableoperating sleeve 88,-and consequently the valve block ll, in either their upper or lower positions. Theinterior of-thereciprocable sleeve 88 is provided at its cehterwith an integratinwardly projecting ring 94 forming seats for the springs 95'an'd 96. The ends 'ofthe springs 95 and 96, remote from the ring 94, abut shoulders 91 and 98, respectively, carried by an operating rod99.

The springs 95 and were dfsu'ch' length that theyare continuously slightly. compressedb'etween the shoulders 91 and98 and'aire of such strength that when the operating rod 99 is moved downwardly, as will be hereinafter described, the reciprocable sleeve 88 will move with a snap movement from its upper position, in which the balls 89' and 90 rest in the valley 86, to its lower position in which the balls 89 and 99 rest in the The movement of the operating rod 99 from one position to the other will be most readily understood by reference to Figs. 2 and 17. The operating rod 99 extends upwardly through a packing gland I and into the spring housing 43 which is movable with the piston members of the jack. The upper end of the operating rod '99 is reduced in size providing a shoulder I02, upon which a movable abutment I03 and a spring I04 normally rest. The upper end of the spring I04 abuts the cap 44 at the upper end of the spring housing. The extreme upper end of the rod 99 carries a nut I of a size which will not pass through the opening in the movable spring abutment I03. 1

As the jack piston rises the spring I04 gradually elongates until the abutment I03 rests upon the circumferential stop I01 formed within the clamping nut 3?. Throughout that portion of the movement of the jack piston upwardly in advance of the contact of the movable spring abutment I03 with the stop I01, the spring I04, by its downward pressure on the operating rod 99, holds the reciprocable sleeve 88 in its lower position.

- When the jack piston has risen substantially to its uppermost position, the nut I95 on the upper end of the operating rod 99 encounters the upper surface of the movable spring abutment I03 pulling upwardly on the rod 99 and compressing the spring 96 until its pressure so far overbalances spring 95 that the reciprocable sleeve 89' snaps from its lower position to its upper position. Conversely, as the jack piston moves to its lower position, the shoulder I62 engages the under side of the spring pressed movable abutment I03 producing a downward movement of the operating rod 99, which compresses the spring 95 and elongates the spring 96 causing the reciprocable sleeve 88 to snap to its lower position. The automatic reciprocation of the piston takes place, therefore, as hereinafter described, between the top of the stroke of the piston and that partially contracted position in which the shoulder I02 contacts the movable abutment I03. The pressure of spring I94 is sufficient to trip the valve rod 99 but is insufficient to prevent the jack from fully retracting under its own weight when the air pressure is manually cut off and the relief valve is manually opened.

The reason for preventing the jack from moving to its fully contracted position during jiggling is that the jack must be placed by hand under the part to be jiggled and, therefore, will not always be tight between the ground and the part to be jiggled before the air is applied. If the jack returned to normal at the lower end of each jiggle stroke, it would be likely to work itself out from under the part being jiggled.

The passageways through which the compressed air is admitted to and relieved from the space beneath the cup washer 34 of the jack piston are most readily traced in Figs. to 16, in-

clusive. Air under pressureis'fed 'to'the lack through conduit IIO. A conical valve III operating on a seat II2 by means of a hand wheel II3 admits high pressure air into the pipe II5 communicating with the valve chamber II6. A double seated valve H8 in the chamber I29; provided with sealing rings I I9 and I20, is moved between its seats I2I and I22 by means of a shank I23 threaded in a packing gland nut I24 and provided at its outer end with a hand wheel I25. The function of the valve H8 is to change the jack from its mere hoisting function to its jiggling function; The valve H8 is shown in" Figs. 10 and 11 in the position for the hoisting function.

When the valve H8 is in its hoisting position, compressed air from the valve chamber I.I6 passes through drilled conduit I21 and lateral conduits I28 to the chamber I29 in which the valve II 8 operates. From the chamber I29 the air passes through the diagonally drilled conduit I30, shown in phantom in Figs. 11, 12, 13 and 14,- to the position in which this conduit communicates with the horizontal conduit I3 I', from which, the air passes upwardly through conduit I32 into the space below the cup piston 34, as most clearly illustrated in Fig. 12. The air passing through these passages causes the piston to rise until'the air is cut off by the rotation of the hand wheel I I3, or alternatively, until the jack piston reaches the top of its stroke, at which point the upper surface of the outer portion of the circular plate 33 contacts the under surface of the guide ring 22. When the lowering of the jack is desired, a valve I35 normally in contact with a seat I36 is opened by means ofthe relief hand wheel'I3I: permitting the air to escape from the under side of the piston by reverse flow through the same passages through which the air was admitted, thence through the diagonally drilled conduit I30, past the valve seat and valve I36 and I35, and to atmosphere through the drilled conduit I39. By moving the valve I35 only slightly from the seat I36 the lowering of the jack may be made very gradual, whereas by moving the valve I35 a substantial distance from its seat I36 the jack will be caused to lower quickly. I

When it is desired that the jack shall operate to jiggle a vehicle, the hand wheel I25 is rotated in a counter-clockwise direction until the sealing ring I20 presses against its seat I22 closing at this point the communication heretofore describedfor the passage of compresed air into the compartment I29 in which the valve II8 op-. erates. With the valve H8 in its jiggling position, compressed air is admitted by the rotation: of the hand wheel I I3 and the consequent movement of the valve III from its seat H2. The air thus admitted to the valve chamber II6 now passes through drilled conduit I9, thence through conduits I30, I3I and I32 to the under side of the piston.

When the jack piston is raised to the top of its stroke, the reciprocable sleeve 88 and its associated valve block 11 are moved to their upper po-' sition by means hereinbefore described, thus closingthe entrance to the drilled conduit I9 and connecting that conduit through the depression I8 in the valve block 17 with conduit 80, through which'the air now passes from the cylinder to the space within the bore of plug I42, into which is threaded a screw I43 from which the apex of its thread has been removed or omitted, as shown at I44, Fig. 10.

By adjusting the screw I43 inwardly or 'outwardly, the length of the triangular ,passageway between the flat portions of, the threads :01 :the screw I43 anditheapex "of the threads 'inzthe plug M2 maybe :c-hanged'to'change the resistance or the flow of :air out ofthe cylinder; By this means the speed .of' lowering of the jack cylinder'may be regulated, whereas the speed of rise of the jack cylinder will, beiregulated by the adjustment of the hand wheel H3.

When the piston reaches a predetermined point 'in its downward movement, the sleeve 88 and valve block Tl are moved downwardly by themean's above described forputting the. bore 79 again into communication with the chamber 6 as shown in Fig. 10 for enabling the compressed air again to raise the piston. This alternate upward and downward movement of the piston continues normally -until the valve H8 is again moved toward-the left to the position as shown in Fig. 10.

It will be understoodithat the diameter of the cylinder and housing 2| will be'selectedin accordance with the weight of the vehicle to be lifted and the 'air pressure available; Inasmuch as my jack is intended primarily for use inautomobile service stations, the air pressure available will ordinarily be that provided for the inflation of automobile tires, usually held at about 100 pounds per squareinchin the service tank.

While I have shown and described particular embodiments of'my invention, it will be apparent tothose skilled in the art that numerous modifications and variations may be made without departing from the underlying principles of the invention. vI :thereforedesire, by the following claims, to include within the scope of the invention .all such modifications and variations by which substantially the results thereof may be obtained byzsubstantiahy the same or equivalent means.

.Having thus descr'ibedrny invention, -.what-I claim as new anddesire tosecure by Letters Patent of the United States is:

In a jack comprisinga cylinder with a pneumatica-lly operated piston therein, an air induction passageway leadingtosaid cylinder, 2. pressure supply valve and a: pressure release :va'lve controlling said'passageway and both operable at will, together with a manually operable 'valve having a chamber included vin :said'passageway, a pair of seats with which said valve :is alternatively .engageabl'e, and an automatic valve actuatedby the piston to cause said piston to rise and fall periodically, the engagement ofzsaid manually. operable valve with one of its -.seats serving to close passages vleadingfrom the valve chamber directly to said cylinder and :to.=open passages leading :irom said chamberato the :automatic valve 'to causes-said periodic movements of the: piston, and the engagement of .sai'dtvalye with the other of said seatssiserving to cut .ofi communication between said valve chamberzgand the automatic-waive andto openifthefpassages leading directly'to :said cylinder for 'placingth'e piston iu'nder control of said pressure supply and pressure release valves.

2. In a jack comprisinga cylinder with a pneumatically operated piston therein, an airunductionpassagewayleading to said cylinder, :8. pressure supply valve and a pressurerelease valve controlling said passageway'and 'both operable at will, together with a-manually operablewalve having a chamber :included 'in said passageway, a pair of seats with whichsaidnnanually operablewalve risralternaltively engageable, and an automatic valve actuated by the. piston within a; limited portion of its full range of :movementin-,the cylinder to .cause said piston'rto rise and fall periodically withinsuch limited :range, the en gagement of said; manually operable valv with one of said seats serving to closepassages leading fromzthe valve chamber directly to said cylinder and to open passages leading from said chamber to the -automatic valve to cause said -periodic movements. of the piston, and the engascmcntof said valve with the other of said seats vin cut ofi communication between the valve-chamberand the automatic valve and to open the passages leading directly to said cylinder for placing said piston-under control of said pressure supply and pressure release valves.

3. In a; jack, thecombination ofapiston movable vertically in acylinder, means providing' w chambers, means for feeding airunder pressure to oneof said chambers, means connecting the other. of said chambers with said cylinder underneath said piston, two separate connections -be-. tween :said two chambers, manually operable valve means for closing either ofsaid separateyconnections while leaving theotheropen, other valve means adapted in one operative position r cluse one of said connections and to :connectsaid other chamber with-an exhaust opening, and automatically operated means for moving ,saidlastnamed valve means. alternately into and out of said on operative position.

4. In-a jack, the combination ofapiston movable vertically in a. cylinder, means providing two chambers, means for feeding air under pressure to, One of said chambers, means connecting the other of said chambers with saidcylinderv underneath said piston, two separate connectionsbetween said two chambers, manually operable valve means in said other chamber ,for closing either of said separate connections while leaving the other open,,o,ther valve means in said, one chamber adapted in one operative position. to close one-of said separate connections and to connect said other chamber with an exhaust opening, and; automatically operated means for moving said last named valvemeans alternately-into and out of said one operative position.

5,. ,In a jack, thecombination of a .pistonmovable vertically in a cylinder, meansproviding two chambers, means for feeding air under pressure to. one. of said chambers, means connecting the other of said chambers with said cylinder :underneath said ,"piston, two separate connections :between said two chambers, manually operable valve means ,for closing either of said connections while leavingthe other open, other valve means adapted in onecoperativelposition to close one of said separate connections and to connect said other chamber withan exhaust opening, and meansactuated by the vertical movements .of said piston in opposite directions for moving/said last namcd valver means alternately into and out of said one operativeposition.

46. In a .jack, a pneumatically operated Lhollow piston, -a-.valve operating rod extending :into the hollow portion 'of the piston a spring surrounding the rod:and;abutting at one .end. against an abutmentifixed with respect to the.- piston, 13in abutment:movable with respect to .the piston against which the other end of the spring abuts, ;a :projection carried'jby the piston :upon .Whi'ChASflld movable abutment rests when 'the .spring:is in its condition of :g-reatestcxpansion, a :shoulder on-rtheryalve operating :rod for-engagement-mth the movable abutment-for moving. the valve operating rod downwardly when the piston moves downwardly to an intermediate position of its stroke, the said valve operating rod being provided with an enlargement for engagement with the upper side of said movable abutment when the piston rises to near the top of its stroke whereby the valve operating rod is moved upwardly, the shoulder on the valve operating rod serving to move the movable abutment relative to the piston when the piston is lowered beyond the intermediate position at which the shoulder on the piston rod engages the movable abutment.

7. In a jack, a piston for movement under air pressure, a cylinder in which said piston may be moved between upper and lower positions by the manual relief of the air pressure under said piston, an automatic valve operating rod, an abutment movable with the piston for'engagement with said valve operating rod to move the rod in one direction when the piston approaches the top of its stroke and to move the rod in the other direction when the piston arrives at an intermediate position in its stroke, the said automatic valve serving to admit the release air pressure from the under side of the said piston whereby the piston will reciprocate automatically between two positions less than the complete stroke of the piston, a spring carried by the piston and acting upOn said movable abutment to move the automatic valve operating rod in one of its directions, the lowering of the piston below the intermediate position in which the movable abutment engages the automatic valve operating rod serving to compress the spring.

8. In a jiggle jack, a pneumatically operated piston, a slide valve for alternately admitting and releasing air to and from the face of said piston, a pair of opposed springs pressing in opposite directions upon said slide valve in the line of its movement, a part of said slide valve provided with a pair of depressions, a ball which is spring pressed into one of said depressions when the slide valve is in one extreme position and into the other of said depressions when the slide valve is in its other extreme position, and operating means comprising a third spring moved by the piston upon a stroke in one direction for applying pressure on one of said opposed springs to cause the slide valve to move in one direction and moved upon a stroke in the other direction for applying pressure on the other of said opposed springs to cause the slide valve to move in the opposite direction.

In a jiggle jack, 3, pneumatically operated piston, a slide valve for alternately admitting and releasing air to and from the face of said piston, a pair of opposed springs pressing in opposite directions upon a part of said slide valve in the line of its movement, a part of said slide valve being provided with two vertically spaced pairs of oppositely disposed depressions, a pair of balls which are spring pressed toward one another into said depressions on the opposite sides ofsaid part of said slide valve when the slide valve is in one extreme position and into other of said depressions when the slide valve is in its other extreme position, and an operating member moved by the piston at an intermediate point in its downward stroke for applying pressure on one of said opposed springs to cause the slide valve to move in one direction and moved at about the end of the upward stroke of the piston for applying pressure on the other of said springs to cause the slide valve to move in the opposite direction, the said opposed springs permitting the slide valve to move from one position to the other with a snap movement.

MARCEL GARANCHER.

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

UNITED STATES PATENTS

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