US1122235A - Lifting-jack. - Google Patents

Description

G. LANE.

LIFTING JACK.

AYPLICATION FILED MAY 8.1914.

Patented Dec. 22,1914.

2 SHEETSSHEET 1.

WIIE WE G. LANE.

LIFTING .IAUK. APPLICATION FILED MAYB, 1914.

1,1 22 ,2 7 Patented Dec.'22,1914

z SHEETS-SHEET 2.

ens-non LANE I COMPfillY,

hirliratziannicd Ma ficr siin m. w a 1 '3 H A To all whom may concern Be it known that 1, Greece Lens. citizen. of the United residing at Foughlzeepsie, New Yorlu, have lDVBXliJQCl cerhain new and useful improvements in Jacks, oi Whichizhe following is a specin cation.

My present invention relates to improvemenis in lifting jacks of she type known step down. jacks, and has among objects to provide a device of this character capeble of economic productioin'oif extreme lightness combined with the requisite strength. and embodying raising and lOWGlflIlg mechanism free from loose screws, nuts or bolts, and of extreme simplicity, thus reducing liability of derangementand faeiliiating repairs or adjustment by the ordinary mechanic.

'lheinvention includes the novelfeatures of construction and arrangement; end coinbination of parts hereinafter described and particularly defined by the appended claims.

A ack constructed in accordance with my invention is illustrated in sheaccompanring; drawings, in Which Figure l is a side elereeion, partly hrolren away. Fig. 2- is a viewat right angles be Fig. 1 looking toward the right. Fig. 3 is a sectional elevation of the upper portion oi the jack. Fig. 4c is a section on line 4.--lof Fig. 8, and Fig, 5 is a. section on line 5-5 of Fig. 3.

Referring by reference cliaruefiers tothis drawingihe numeral 1 desigi'iates the base which is preferably composed of a square plate of sheet steel of desired size and thicle ness, and 2 e standard Within which is guided the lifting; bar This slandard is of special form designed to secure combined li hcness and strength, and comprises pair 0i channel irons 2 and 2" of steel or oiher suitable material of diilt'ereni; depths and lit.-

ting one Within the other, a s shown, so to leave a space between the bases i the channel irons and the side walls or the channel iron 2 which receives and guides the lifi3- ing bar. The edges of the channel irons are securely riveted together. as indicated a, and the outer channel Q -lS provided at l' ZS lower end With outwardly turned integral Wings or flanges 2 which ere firmly secured tothebase by su table n such as r velgs, ssindicahed-ieii 0. Thai 'eted or otherwise secured to e end oif'ilie standard the ii" is Gill) a m ins and. h

din

pair 4. passi edges 0% pawl is pivoiinlly conna. the lifting lever 3, .ferahly ing the end of the pa wl and reduci. of the liftii'ig lererio pert; .lv'Z ii; to lit uewrecn the legs of the pawl and he connec'zel to hv she pivot pin 7..

The lifting lever is niroicd her side plates 8 which. with the cover or can 9. constituie a casing to receive the pawl controlling parts these. side nlaies 3 he L H .e LG 11116 3116. O1.

bi ill C3 L" side walls of she cl annel iron 2". The iii;- ing lever is pivoeallv inouuccd upon a nin 16 supported hv the plates. and the extensions or cellars S are provided on each side of the lifting lever or lree iiing it nronerljfi centered on she pin. lEv making; these on tensions or collars inteo'ral Willi the lii t uo: lever the latter is held nroperl v centered and a longer bearing surface on the pigos pin afi o dcd.

The lift ng; and holding; oawls a mallv snring' uressecl town d li'F" ratchet l ar, and act alieruai 'l ner Well i need an etc-n shore a .l below a z through the pivot 01': the enema" lemr i"- Y 1 I I, w .Eliese hell cran; levers are aeaoted lo he mechanism nre'i erahlr in the form 0'! snrina" inieruciino; between the "mo us is,

such for insliunce as the s rine; C. and when 1 i pushed toward lllfi 'oaWl by suitahle spring;

alternately ride over the teeth of the lifting bar when the jack is operated for lifting purposes as hereinbe fore referred to. Any form of pushing connection may be used vto transmit the elastic tension of the spring C through the pawls. In order that the pawls may be operated to effect the step by step lowering in the manner hereinafter described, it is necessary that there should be anelastic connection between the bell cranks 11 and 12 and the pawls 5 and 4 through whichsaid bell crank levers will, when.

rocke on their pivots, tend to yieldingly pull on the pawls 5 and 4. I find that I can accomplish this double function of pushing on the pawls in one direction and yielding or elastic pull on them in the opposite direction by means of close coil springs 13 and 14C connected respectively to lugs or eyes on the pawls, and similar eyes on the ends of the bell crank levers. hen the bell crank levers are free to move toward the pawls under the action of the spring C, the coils of the spring 13 and 14 being in contact, said springs act practically as rigid links, thus pushing the pawls toward the ratchet teeth, any yielding permitted to the pawls being due to the action of the spring C. It will be apparent, however, that either of the bell crank levers 11 or 12 being swung away from the p'awls 5 or 4-, this would place a tension on the respective spring 13 or 14. In order to effect this movement of the bell. crank levers to pull the pawls, out of engagement with the ratchet teeth at the proper time to permit the lowering of the jack as the handle is moved up and down, I provide means on the handle adapted to cooperate with the arms or portions 11 and 12 of the bell crank levers, this means on the handle or operating lever being -movable so that it can be set in a position ineffective with relation to the bell crank lever during the lifting operation, and being shifted to effective position for the step by step lowering. A convenient means of efl'ecting this purpose is to provide a rotary contact member 15 thin and relatively wide, and of such dimensions that when it is turned in horizontal position it will move up and down with the lifting-lever without either of its flat sides coming in contact with the bell crank levers. lVhen turned into a vertical position as shown in Fig. 3 however, as the lifting lever is moved up and down, the upper and lower edges of the contact piece will alternately contact with the arms or portions 11 and 12 of the bell crank levers, rocking them on their pivots and alternately placing tension on springs 13 and 14.

It is thought that the operation of the parts thus described in the step by step lowering of the lifting bar will be apparent. but it may be briefly stated as follows: lVith the contact piece turned vertically,

when the handle or lifting lever is lowered, the lower bell crank 12 is forced backwardly, stretching the spring 11-, and when the load is taken by the top pawl 5 the lower.

or holding pawl 4: is pulled by the spring out of engagement with the ratchet teeth.

Then on raising the handle lever (3 (which lowers the load) the contact piece releases the lower bell crank lever, which again takes up its normal position actuated by the spring C to push the pawl forward, and when the lifting pawl has been sulliciently lowered the holding pawl intercepts the next tooth and holds the bar 3 against further downward movement. In the meantime, the upward movement of the contact piece 15 has rocked the bell crank 11, applying the tension to spring 13, so that the moment the weight of the load is taken by the holding pawl and the upper pawl relieved of the weight, the spring 13 immediately pulls the upper or lifting pawl out of engagement with the ratchet teeth. In either case the bell crank lever can not get back into its normal position until the lifting lever has approached the center, that is, until there has been sufiicient movement for the pawl to pass the point of the corresponding tooth in the rack.

A convenient manner of effecting the rocking of the contact piece or control device is to provide it with a thumb or control lever 16. The end of this control pin has a surface squared as indicated at 15 that projectsoutside theoperating lever on the opposite side and against which a spring 17 presses, tending to hold it in either the raising or lowering rotativc position as placed. Outside of this the control lever is attached. A feature of this spring arrai'igement is that the control device will be thrown fully into position and held there, for as soon as it well passes center the spring aids in the movement. This avoids the obiections incident to careless operators failing to get the control lever fully into position as well as its failure to stay there.

In order that the lifting bar may be quickly lowered or released and allowed to drop when no load is on it, I provide the bell crank levers with linger projections 11 and 19* which may be pressed toward each other to simultaneously rock both bell crank levers and place both springs 13 and 14 under tension simultaneously.

The lifting lever is provided with the usual socket (3 to receive an extension lever (not shown).

Having thus described my invention what I claim is:

1. A jack comprising a standard or guide, a lifting bar, an actuating lover, a lifting pawl and a holding pawl cooperating with said lifting bar, a spring for normally press 'ing said pawls into operative relation to the N new guide and. crept-ed lo engage the ratchet her, an colonel lever, gin operating pawl piv; to the "ver ei'igsging the ratchet oer, spring; for pressing said pawls loword the ratchet bar, conno on the cornering lever for alterlying yielding tension to said ils lenolng lo drew them outwardly from Lie ratchet as the lever is-oscillsled solo-- lv described.

53i: comprising standard or guide, our, an actuating lever pivoeolly ineclzed with the gui l 7 s holding pawl the guide, 21 li'lling pziwl pivoled e pairnoi bell crank levers pivconnecled with the lifting lever, e i inlerociing between said bell crenlr levers and lending to push the pswls inlo eninen'; with "the ratchet oer, springs convell crank levers with e 1e pelvis carried. by the actuating lever snid bell. crank levers es the ever is oscillated.

ill see. comprising a stendsrd or guide,

lll

or niovnlile longitudinally ll'iereof, lioldin owl pivclallv connected with she guide coo eereling Wllil'l sold can, an ac:-

lzneling leven llierewiili c pair of hell from nec'ling said 2; spring inle vb su "pawl 'oivolellv connecl'ed with said loom ers pivolzelly supported. close coiled crenlelevers w lev lzli 'ing s s 'nricerd or guide,

crnnling 7 a lever pivolgellv guide s holding pawl guide on operating pawl pivemailing lever, a pair of hell crank levers pivo'izslly supnoreed from the standard 21 spring interacting; laelaween said loell crnnl-r levers end tending to push the pewls into engagement with the relzcliet leer springs connecting the bell cranlr levers with the paw'ls, a contact device carried by the cornering lever for operating said bell crrinli levers es the need lever is oscillated, and

means for moving said seen sing device into end one of operative position will: relation lo said cell crank levers.

gnide, {l

v A eck comprising e nlndnrd or I e ljlll; en detecting lever n pnwl and lioldigngg pawl. cooperating; will lilteing leer, cl -sed UICESE S21.

lownrd die liar springs connecting said. bell crank levers with the pewls, and e conlace device carried by theeclueting lever and movable into and out of the path of the bell crank lovers. 7

, 7'. ll. jack comprising a standard or guide,

e lifting bar, on actuating lever, a lifting said lilting bar, a spring l'or normally press-' ing said pswls into operative relation to the lifting leer, a separate spring connected to (ifiCllPEiWl, and means operated by the actusling lever, for alternately applying tension to said separate springs, and means for rocking the bell cranks simultaneously. 7

9. A. jack comprising; a si'sndard-or guide, all actuating lever, a. lifting pawl and e holding car, a of bell crank levers pivotall supported from the standard and adapted to press seid pewls toward the lifting bar, e ll? shaped spring having its ends connected to said bell crank levers, elastic connections between the bell crank levers and pawls,

pawl cooperating with seidlii'ling nd a contact device carried by the operating lever guide a lifting bar, on actuating lever, a lifting pewlend 'llolding pawl cooperating with said lilting bar, a pair of springpressed bell crank levers pivolally supported from the standard and adopted to press pawls toward the lifting bar, springs connecting said bell crank levers with the pawls, and e rotary contact device carried by the actuating lever and having a contact portion adapted to contact with said bell crank levers in one position of the contact device.

ll. A jack comprising e standard or guide, a lillingloar, an actuating lever, e lifoing pawl and a holding pawl cooperating with said lilting bar, a pair of springpressed bell crank levers pivotnlly snpported from the standard and adapted to press said; pswls toward the lifting bar springs connecting said bell crank levers with the pelvis, and a rotary pin carried by said cornering lever and having e thin and rolelively wide portion projecting between said bell crenlr levers, substantially as described.

15% 'l l: comprising a vstinderd or guide, lg ber an actuating lever, 51 filling pevm and e holding pawl codperel circular portion, and a controlling spring bearing against said non-circular portion.

In testnnony whereof, I aihx iny signature in presence of two witnesses.

GEORGE LANE. Vitnesscs:

WM. C UCK, C. J. Bnownn.

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