US1852545A - Jack - Google Patents

Description

l. A. WEAVER April 5, 1932.

J ACK Filed May 11, 1929 5 Sheets-Sheet 1 April 5', 1932.

. I. A. WEAVER JACK Filed Maly 11. 1929 3 Sheets-Sheet l otent l 1932 STATES PATENT OFFIC ill. Wnnrnn, t3! SIPM'N'GI'IELF, ILLIIN' U18, ABSIGINOB 1'0 WEAVER. MANUFAUIUIE- Il'ilt'fil (90mm, 01'' SPBHWGIHIELD, ELINOIB, A CORPORATION 01" ILLINOIH Application allot flay ll,

'lllie present invention relates more particulorly to truck-j acke oi the hyclraulic type, the oererol features of novelty and improvement residing more or less in the structural I "r elierocteristics oi the mechanical elements eniplo yerinnol in their cooperation with one nnotlrer, one of the prime time oil the inven tion loeing the provision or 9; incl: of this type which in comperetirely simple in etruetnre, Willfiil possesses greet lilting power tor ite; nine rrntl "which can lie operetecl with relative ease enel Facility, other features oi advantage out which will ioecorne apparent from o eon eieleretion e present, preterreil emcliinent oi? the intention illnetraterl in the no eonrpnnying drawings, forming e art of thin e rreeilieetion, enrl throughout t e severel rierre out which lilre reierence ntlmernle have been employed to designate the see ports.

'"lreoe elretringe: irgnre l in n, eicle elevntion oil the irnprorerl ncl: showing the loerl-earlelle in 'll'l its lowermost position in flotterl in most elerntecl reletioni m lfilltt') F in plnn riew of the jTeclr ehown in ll, operating handle being trolcen ltrngrnentery entl elevation oil pnrtr were we l trorn line it control, "rertieel, longitnriinnl i e Figure in;

l more 8 is n fragmentary, lo llwine flee tion on on enlergecl ecele on the line it-F out Figure l; v

Figure '2" is o cross-section on enlncreheel ncnlc on line 1?'--l oi Figure't; T

Figure t in en elevation of the handle equipped enel o'l' tlre jock;

Figure 9 in on enlerget section of lineg9-9 figure 2;

til

tion on line ill-ill of El re tlgnml Figure 11 in on amplified. fietailssction ehowing the bell-valves controlling the oper-' etion oi the oil-pump.

By reference to these drawings, it will be l reg-ore ill in e we ifierl n rtiul x gm Mp upstanding, reto mngiprojections or loge 10 mm Io. QMWO.

permit oi its reinforcement at this point not to nllow tlle loaii saolrlle to descent to a greet or extent, not the enol oi the element 21 is somewhat flattened horirzsontall'y onol slottefl along its opposite sides to provicle upper anal lower terminal sections and Q5 which receive between them tlie aentral portion oin t3ll'0BS-llfll E26 pivoterl on an upright bolt 2'? ant enpplieol at ite opposite enols with eppro printe carrying- wheels 28, 28"

[in order to strengthen such pert oi the en plinnce, tile tu'hnlnr mern oer is proriclecl internelly with n reinforcing block or bar shopecl to conform to and bearing on the in nor, lower surface of tire element 21!, being welrlei, ri'veterl, or otherwise eecnrorl in no eition, enclr part 29 having a tilnrceteil encl prorirling two eere Fl end 552 osecl lietrreen tire ripper enel lower enrineee oi the leer Flt encl time nfiieeent inces of tire cylinfler eeetions end Q5, time pirotliolt 2?" extending thronglr registering apertures; in all live porter,

, ell no in elenrllt renown in Fignre l.

In order to maintain the seat or safldle always practically horizontal in all of its various degrees of elevation, a link 42 of proper Flt 49 therethrough normally closed by a screw 51, leading inwardly to the hall raceway 47 and of a size to permit the introduction or extraction of only one of such balls at a time,

provided the plug is removed for thatpura suitably-packed power-piston 73 adapted pose, the set of such balls also fitting in a concave, circular raceway 52 in the shank of a caster-yoke 53 in which a caster-wheel 54 is mountedto revolve in usual manner.

From this description, it will be clear that each one of such ball-bearings is completely protected from dirt and water and that the balls themselves act as a retaining means for the shank of the caster-wheel yoke in the recess provided in the supporting member 45.

In assembling these parts, the upright caster-wheel journal or stem is introduced into the vertical bearing in the bracket so that the two raceways are in register, whereupon the balls are inserted individually in succession through the aperture 49 until they have all been introduced into place, whereupon the plug 51'is inserted to prevent their unintentional removal.

This construction provides a simple means for a protected and shielded ball-bearing, the

members of which cannot become accidentally separated, and which is fully and completely fortified or preserved from foreign matter reaching it, particularly from above,

. it being understood that these jacks are somecommodated between a pair of retaining straps 57 riveted against the opposite sides of the shank of a link 58 having in its corresponding end a substantially semi-circular recess 59 forming abearing for the part 56.

The link or connecting-rod 58 has a vertically-flattened enlargement 61 of substantially the same diameter as the internal calibre of the cylinder 21, such part 61 being rounded on its top and bottom to maintain a snug fit 1n the cylinder in its various positions of oscillation and to take at least a part of the strains.

This enlargement 61 has a cavity 62 and aligned hearings for the journal 63, 63 of a cross-shaft 64 flattened on one side at 65, the rounded portion of the shaft conforming to and bearing on the companion, curved surface 66 at the inner end of the recess 62.

Cylinder 21 is provided internally with a stationary, division wall 67 expanded to form a tight fit therewith, so that there is a fluid tight connection between the Wall and the cylinder, the former being centrally apertured and equipped with a stuffing-box 68 for the accommodation of a reciprocatory pistonrod 69, the flat end 71 of which bears against the plane face of the shaft 64, such rod 69 having an annular groove 72 around it which receives the inner end of a retaining screw 73 extended through the part 61 to hold the link or connecting-rod 58 in operative association with the piston-rod 69.

At its other end, the piston-rod 69 carries to fit and to reciprocate in the cylinder.

The adjacent end of the cylinder is internally threaded and accommodates a screwthreaded disk or plug 74 equipped with apair of threaded studs 75, 75 extended out through apertures 76 in an end-cap 77 having a flared mouth 78 fitted closely over the corresponding, external, converging or tapered surface 7 9 on the endof the cylinder 21, nuts 81 on the studs, with intervening washers 82, drawing the parts firmly together, so that there is a very tight and accurate fit between the cap and the outer surface of the cylinder, the construction being such that the parts can be readily demounted, or separated, if neces sary, to afford access to the inside of the appliance. Cap 77, in its lower portion, has a longitudinal, cylindrical cavit 83 accommodating a conformable, slidab e, suitably-packed plunger 84 extending out of the casting 77 through a stuffing-box 85, the protruding end of the plunger being connected by a pair of links 86, 86 through spacers 87, 87 and a shaft 88 to the two arms 89, 89 of a yoke 91, oscillatory on a shaft 92, supported in bearings 93, 93 of a forked portion 94 of the end casting 7 7, a coiled, torsional spring 95 surrounding that portion of the shaft 92 between the sides of the section 94 of the casting and one end 96 hearing against the casting and its other end 97 underlying the web of the yoke 91,-as is clearly indicated in Figure 8.

Thus the spring tends to rock the parts in a direction to draw the pump-plunger 84 to its outermost position, another yoke 98, embracing the yoke 91, being also rockable on the shaft 92 and its center provided with an upstanding rod or stud shaft 99 and encasing sleeve 101 welded to the yoke a tubular handle or lever 102, equipped with a top cross-bar 103, at its lower end extending through an aperture of, and welded to, a bent arm 104, oscillatory on the member 101 and mo'vably held to the yoke 98 by a clip fastened to the latter.

Arm 104 has a ball and socket connection 105 with a rod 106 pivotally connected at 107 with an arm 108 rigid with the cross-bar 26,

narrates the construction being such that the turning ot' the handle or lever 102 103 about its own unis roclrs the her 26 and the wheels 28 around the tulcruna bolt 21 to sheet the desired steerot the truclnjaclr.

l urningr to Figure 11, it will be noted that the plug or dish 74 has a passage 109 therethrouph so that the oil or other liquid from the pump did-d4 may pass to the powercylinder 21 and may also flow back to the oil-reservoir to the right of the power-piston when permitted to'do so.

The end ol the pump-eylinder 83 is made tapering at 111 to receive a correspondinglyshaped valve-plug 112 having a side port 118 controlled hy a ball-checkwalve 114 in a larger, cross passage 115 which intersects a longitudinal conduit 116 opening at one end into the puinp eylinder 83 and connecting at its other end with a port 117 opened and closed by a ball check-valve 118 and extended heyond the adjacent surface 119 oil the castin s" W, whereloy the liquid trons the pumpnder may be delivered through the port into the conduit 109.

1131s in direct connection with a pas- 121 in the casting 1''? leading to a transverse cavity 122 in its lower part (Fig. '1" which, by another passage 123, in direct association with an external pipe or conduit 124 leading to a connection 125 6) and a port 126 through the cylinder-wall, which port is adapt-ed to be opened and closed by a- Ll vtl 12'? riding on the corresponding porin the inner surtace ot the cylinder 21 ai ing a longitudinally and transversely connection with the power piston '23 an attachment screw 128 smaller in on throu chains-er 122- 1'} has a during which receives a taperedvalvehaving an annular groove 132 connected diametrically-oppo L xi lay a cross-passage 183 which also rsects longitudinal cavity 134 in the 1 r equipped a valve-seat and balli e 135.,

tr "l'l is also tarnished with a passage 111th h igs. d and l) which connects the space hetween the elements 7 4 and 77 with the an nu 11" groove 132 allowing the ball-valve 135 t be employed to govern or control the de scent oil the lifting-member of the jack.

he hallvalve 185 is normally held closed on seat lay a plunger 137, slidable lontudinally in a plurality of aligned apertures in series of plugs 138, 188 screwed into one threaded end of the chamber 122, a coiled spring 139, encircling the rod 137',

pressing at one end against the innermost plug; 13% and hearing at its other end against trusted against the action of such spring, the ball-valve will be permitted to open automatically and to establish a connection between that portion of the cylinder 21 to the left of the power-piston 73 and that part of the same cylinder to the right of such piston.

To draw back or retract such spring-actuated, holding member, a bent lever 141 is tulcrurned on the cap-casting 77 at 142, its slotted, depending extension 143 (Fig. 9) straddling the rod 187 adjacent to a terminal not 144 screwed on to its threaded outer end, the tree upturned end portion 145 (Fig. 1) of the arm 141 overlapping the outer face of a foot-lever 146 (Fig, 8) having a hub 147 oscillatory and also lengthwise slidahle on theshaft 92, such lever having a foot-piece 148' and a projection 149 over lying the front edge of one of the bracket arms 89.

11 such short-stroke pedal 148 is rocked upwardly and downwardly hy the foot, which can be accomplished much more rapidly than the corresponding" hand movement of the handle or lever 102, the pump can be actuated relatively more speedily to secure a quick initial rise of the loadsaddle.

During; such actuation of the t'ootdever 146, the handle 102 remains stationary, the yoke 91 being automatically restored to position by the spring 95 after each down-rockmg movement by the toot-lever This constitutes a simple and effective means for securing a rapid, preliminary, upward travel of the seat to the load.

rln auxiliary handle 151, (li'ia. E3) is pivoted to the lever 102 at 152 and is connected by a link 153 to a slotted cam 154 through which the shaft 92 extends.

"When handle 1211 is down as shown in Figure 8, valve 135 remains closed owing to the pressure o'l the plunger 13? against it, hut when it is desired to lower the load, the handle 151 is swung upwardly thereby litting the cam 154 and shifting the lever 146 on and lengthwise of the shatt 92, with a complementary rocking movement of the lever 141',which retracts the plunger 13'? from the ball-valve 135, allowing the latter to open, thus permitting the oil to flow from the cylinder 21 on one side of the powcr-piston 73 to the same cylinder on the opposite side of such piston.

The jack is operated practically as follows, assuming that it has been rolled to correct position with its seat or saddle directly helow the load to be lifted:

The operator, by his foot, Works the pedal 146148 up and down several times, comparatively rapidly, at each upward actuation, causing the pump-plunger 84 to travel to the left, which movement sucks oil into the pum -cylinder 83 from the oil reservoir in cylin or 21 to the right of the powerpiston'73 through port 126, connection 125, conduit 124, passage 123, chamber 122, aperture 121 and port 113, the ball-valve 114 automatically opening under such circumstances, and each time the foot-lever is rocked down, effecting the inward travel of the plunger 84, such charge of oil reviously drawn into the cylinder 83 being orced out thereof through passage 116, port 117- and aperture 109 into the cylinder 21 to the left of the power-piston 73, which it forces along a correspondln amount to the right, the swift foot working of the lever resulting in a relatively-quick ascent of the seat or saddle to the load.

Then greater power is required to lift the load step-by-step and this is accomplished by more slowly rocking the longer handle 102, 103 up and down the required number of times, thus operating the same pump at a reduced speed.

When the load-saddle and the bell-crank lever reach their uppermost ositions, piston '7 3 will have moved sufficient y to cause valve 127 to cover port 126 over which it is firmly held by suction, if operation of the pump is continued, thus shutting off the supply of oilto the pump, which action precludes fur er elevation of the load.

To lower the saddle and its load at a substantially definite or predetermined low speed .or-rate, the workman swings handle 151 upwardly, thereby allowing valve 135 to open automatically by reason of the oil pressure acting on it, and permitting the oil on the left-hand side of the power-piston to flow to its other side, such oil transfer letting the load and saddle or seat gradually descend the required amount usually to its lowermost position, valve 127, by reason of its loose mounting on the piston, readily opening upwardly to allow such oil flow. Y

- It will be noted that oilunder substantial pressure is present only in the pump cylinder 83 and in the power-cylinder to the left of the power-piston 73, the chamber to the right of the power-piston comprising an oil reservoir one wall of which is formed by the plug or closure v67 v The latter is held in place in the tubularmember or cylindrical shell solely by friction,

i and, to obtain such a suitable fit the member 67 has two flaring walls equipped around their peripheries with a small amount of packing material.

After the part 67 has been properly positioned its diverging walls are squeezed toward one another, thus enlarging its diameter adequately to obtain'the required frictional The packing, which is employed in grooves around the member, is used merely as a safeguard to assure complete closing of any scores on the inside of the cylinder.

Although herein only one desirable embodiment of the invention has been resented, those acquainted with this art wi understand that it is susce tible of incorporareadily 7 tion in physical forms di ering substantially from one another in mechanical details.

In some cases it may be desirable to employ a coiled spring 200 bearing on the piston or plunger 73 to assist in returning the loadsaddle to its lowermost position, but, in other instances, such spring may possibly be dispensed'with. v

I claim:

1. In a lifting-jack, the combination of a tapered plug hav1n a side inlet-port and a side outlet-port an a. longitudinal passage connecting said ports together and open at one end of the plug, check-valves controlling said two side ports, a hollow pump-cylinder having a tapered end recess adapted to receive said plug, a plunger reciprocatory in said cylinder, and means to operate said plunger.

2. In a lifting-jack, the combination of a. substantially-horizontal hollow cylinder, a. bell-crank lever fulcrumed on the jack, a load-saddle mounted on said lever, a powerpiston slidable inside of said cylinder, a liquid pum connected to said cylinder and adapted to slide said piston inv said cylinder to raise said lever and load-saddle, means to release the liquid in said cylinder to permit descent of said lever and saddle, and means connecting said power-piston and bell-crank lever including a rocking-link having a rocking and sliding bearing'on the inner surface of said cylinder.

3. In a lifting-jack, the combination of a substantially-horizontal hollow cylinder, a bell-crank lever fulcrumed on the jack, a load saddle mounted on said lever, a power-piston slidable inside of said cylinder, a liquid pump connected to said cylinder and adapted to slide said -piston in said cylinder to raise said lever and load-saddle, means to release I the liquid in said cylinder to permit descent of said lever and saddle, and means connecting said power-piston and bell-crank lever including a link having sliding and rocking bearings on the top and bottom inner surfaces of said cylinder.

4. In a lifting-jack, the combination of a substantially-horizontal hollow cylinder, a lever fulcrumed on the jack, a load-saddle mounted on said lever, a power-piston slidable in said cylinder, a piston-rod on which said power-piston is mounted, closures for said cylinder through one of which said piston-rod extends, a link hinged to said lever, a cross-shaft rockingly mounted in said link and having a flat face, the plane end of said piston-rod bearing on said flat face, a liquidpump connected-to said cylinder and adapted to slide said piston in said cylinder to' raise descent of said lever and saddle;

5. In a lifting-jack, the combination of a substantially-horizontal tubular-member, a lever fulcrumed on said jack, a load-saddle mounted on said lever, spaced closures for said tubular-member forming a power-cylim der between them, one of said closures being apertured and held in place solely by its friction with the inner surface of said tubularmember, a piston-rod slidable through said aperture, means operatively connecting said piston-rod and lever a power-piston on said piston-rod and slidable in said power-cylinder, and means to effect the reciprocation of said powe1 -piston in said power-cylinder to raise and lower said lever and load-saddle.

6. In a lifting-jack, the combination of a substantially-horizontal tubular-member slotted along a portion of its top, carryingwheels for said member, a bell-crank lever fulcrumed on said member and occupying said. slot, a load-saddle mounted on said lever, a closure for an end of said tubular-member, an apertured closure for an intermediate unslotted section of said tubular-member and held in place in the latter solely by its friction with the inner surface of said member, a piston-rod slidable through said aperture, a stuffing-box on said apertured closure cooperating with said piston-rod, a link con-. necting said piston-rod and bell-crank lever, a piston on said iston-rod and slidable in said tubular-memher between said closures, a pump to force liquid into said tubularmember between said end-closure and said piston to eflect travel of the latter to raise said bell-crank lever and load-saddle, and means to release the liquid from such chamber to allow descent of said bell-crank lever and said load-saddle.

7. In a lifting-jack, the combination of a substantially-horizontal hollow cylinder, carrying-wheels for said cylinder, said cylinder having an exterior tapered surface at one internally screw-threaded end thereof, a threaded plug in said cylinder and engagin said screw-threads, an end-closure for said cylinder having an inner tapered surface fitting over and bearing on said complementary tapered surface of said cylinder, means detachably securing said plug and closure together, a division-wall fixed in said cylinder dividing it into longitudinal sections, a power-piston fittin and slidablein said cylinder between saif plug and division-wall,

a piston-rod, on which said piston is mounted and slidable through an aperture in said In witness whereof I have hereunto set my hand.

IRA A. WEAVER.

division-wall, a load-saddle near one end of the jack, means operatively connecting said piston-rod and load-saddle, a pump having valved conduit connections with the liqui reservoir between said piston and divisionwall and with the power-cylinder between said piston and plug, means to operate said pump to cause said load-saddle to rise, and means to connect said power-cylinder with

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