US1298895A - Lifting-jack. - Google Patents

Description

W. CLEMENS.

LIFTING JACK.

APPLICATION FILED 1AN.5.1919.

1,298,895. f I Patented Apr.`1,1919.

INVEN TOR.

MLM/f Cifra-Ns- WILLIAM *('ili'flilVlENSa 0F SAN FERNANDO, CALIFORNIA.

LIFTING- JACK.

Specification of Letters Patent.

Patented Apr. 1, 1919.. l

Application led January 6, 1919. Serial No. 269,861.

To all whom t may concern.'

Be it known that I, WILLIAM CLnMENs, a citizen of the United States, residing at San Fernando, in the county of Los Angeles and State of California, have invented new and useful Improvements in Lifting-Jacks, of which the following is a specification.

My invention relates to lifting jacks and more particularly toa lifting jack adapted to be suspended from' a derrick or overhead beam. 4

An object of my invention is to provide a lifting jack suitable for lifting objects which are normally at some distance from the ground, such as wagon beds and the like.

With this and other objects in view, my invention consists inthe construction, combination and arrangement of vparts lherein shown, .described and claimed. Y

In the accompanying drawings, which form a part of this specication,

Figure 1 is a side elevation showing a lifting jack embodying the principles of my invention suspended to an over-head beam, parts being broken away toshow theN c onstruction. f

Fig. 2 is an enlargedsectional detail on the line 2-2 of 1.

Fig. 3 is an enlarged sectional detail on the line 3-3 of Fig. 1 showing the vconnec- V tions of the links with the lever and showing the spring which acts to hold the catch pins against the rack bar.

Fig. 4 is a fragmentary edge view looking in the direction indicated by the arrow 4 in Fig. 1.

Fig. 5 is a view analogous to Fig. 1 and' showing a different operation.

Referring to the drawings in detail, a supporting frame 1 has a hook 2 attached. to its upper end and the hook 2 is suspended from a beam 3 by a cable 4. The supporting frame 1"is made up of a wide middle bar 5 which serves as a rack bar and the outer guide bars 6 and 7 there being spaces 8 and v9 between the guide bars and the rack bar.

The rack bar 5 has a series of rounded and upwardly turned notches in each of its sides 10 and 11, said notches being staggered with reference to each other, so that a notch on one side is midway between two notches on the opposite side. A link 12 is formed of parallel bars 13 and 14, the lower ends of lthe bars being connected to a hand lever bar 15 by a pivot bolt 16. The upper ends of the link bars are connected by a catch pin 17 which holds the bars spaced apart, so that the catch pin 17 will engage in the notches 11, and so that the bars 13 and 14 will work freely in opposite sides of therack bar 5. A similar link 18 consists of two bars connected to the hand lever bar 15 by a bolt 19 with a catch pin 20 at itsupper end to engage in the notches 10. A' retractile coil spring 21 has its ends attached to the links l2 and 18 a short distance above the hand lever bar. 15 by bolts 22 and 1 23,'the tension Adownwardly out ofthe notches 10 andl 11.

A hook 24 is pivotally connected to the hand lever bar 15 half way between the bolts 19 and 16, and the'hook 24 is adapted to carry the load to be lifted. The ends 25 and 26 of the hand lever bar 15 are round, so that pipe extensions may be slipped over the ends 25 and 26 and used as operating handles. A throw-oil' lever- 27 is connected lto the bar 13 by a capI screw pivot 28 extending looselly in the intermediate portion of the lever.` handle 29l extends outwardly fromthe long end of the lever 27, and a tongue 30 extends inwardly from the short end of the lever. The lever is bent in sideelevation so that the long end 31 hangs downwardly from the pivot 28, and the short end 32 extends upwardly and laterally from the' pivot nearly at a right angle. The tongue 30 of the throw-oli' lever 27 engages the inner edge of one of the bars of the link 18. An'operating cord 33 is connected to the handle 29. When the cord 33 is released the long end 31 of the throw-off lever 27 will hang downw-ardly and swing freely upon the pivot 28.

The jack thus constructed may be operated from either end of the hand lever bar 15 or from both ends simultaneously, and as the hand lever bar is vibratedup and down the links 12 and 18 will alternately raise and lower, and the catch pins 17 and 20 will alternately carry the load, andthe load will be raised or lowered stepbystep.

Assuming that the hand lever 15 is being operated from the .right-hand end, as shown in F ig. 1, the pipe extension is slipped over the round end 26, and the pipe extension is omitted from the other end. Upward move- ,ment of the handle will bring the link 18 into position with Athe catch pin 20 in the notch 10, and the catchpin will support .the Y load while the link 12 moves upwardly until `the catch pien .117 moves vinto the next notch 11. Duringthisoperation the `pivot bolt 19 isfthe fulcrumofthehand lever 15. Down- .ward movement of the handle will thenf v.throw .the load upon the catch pin 17 and Athepivoti'bolt -l'becomes the fulcrum .of the hand :lever 115. This action will cause the link .18 .fto move upwardly until vthe catch ,pinQOengages .the next .higher notch and so -on`. Thus by alternately xraising and lowerringthe.handleand vibrating the hand lever :15 the-catch pins 17 and .QOalternately moveV ferate Vthe throw-off lever 27 to push the -tongue 30 against .the :link 18, thereby mov-V ing .thelink vv18 to move the catch pin V20 into the .space 8 Aclear `of the rack bar; then the .handle will :be operatedY to lower. the catch .pin2`0 to the .next .notch below, and the cord 3-3 released, then ithe; operation of the handle l-wilvlbecontinued xto throwtheload upon the ,catch ,pin 20,;.thenthefcord .33 will be pulled .ato throw the catch Apin 17 .out ofthe .notch .and .therhandle vwill-be :operated =to lower the Ycatch .pin 1:7 :to :the next notch asshown in VF-ig.' 5 :and :this `operation is continued to lower the 'load step zby step.

Variousfchanges may be made without departing fnomthe spirit of my invention as claimed.

.Iclaims l. .A li-tting jack comprising, a rsuspended l .suppor-tingbar, said supporting bar consist- 'ingsof .la .middle two edged rack :bar and two parallel guide 'bars in spaced relation to the :edges of the .rack bar; Va .catch .acting .along :and in engagement with each of .the Atwo .notched edgesaof .said rack bar between said .guide .bars andssa'id rack fbar; a r'lever adapt- .ed to be operated at either end; :links op'er- .ativelylconnecting said catches to said lever bart;V meansfforv suspending .said .supporting bar; and .means 'for attaching the load to said leverbar.

` .52. A lifting'jackcomprising, .a suspended supportin'gbar :consisting of a middle two edged rack bar and two vparallel guide bars in spaced relation to the edges of said rack bar; catch. pins acting along the edges and in engagement with the notches in said rack bar.; a lever .bar adapted to be operated at either end; links in the ulpper ends of which saidcatch pins are iixed and the lower ends of which are pivoted to said lever bar in spaced relation to each other.; a retractile spring having one end fixed to each of said Ylin-ks and `.adapted to pull said catch pins fixed in the upper ends of said link into the notches in saidprack bar; means forsuspending .said supporting bar; and .means for attachingthe load .to said lever bar.

.3. .A lifting Ajack comprising, asuspended supporting bar, said supporting bar consist+ ing of a middletwo edged rackbar andtwo parallel guide bars in spaced relation tothe edges of the rack bar; acatch 4acting .alon land in .engagement with each of the two to said lever-bar; .and athrow-o' lever pivotally `connected to one link and adaptedto .engage the other llink.

4. A lifting jack comprising, asuspended `notched,edges-ofsaid yrack bar Aloetween said supporting bar .consisting 'of a middle two edged rack bar andftwo .parallel guide bars in spaced .relation to theedgesof .said rack bar; catch vpinsacting along the edges .and in engagement with the :notches in said-.rack bar; a lever bar adapted'to be .operated at either end; links in the upper ends .of which saidcatch pins .are fixed .andthe lower ends of which are pivoted lto said lever l:bar `in Y spacedrelation :to veach other; a retractile spring having one endiixed to each ofsaid links and adapted Yto .pull :said catch pins fixed in the upperends of saidlinkinto @the notches in said rack bar; means yfoi-:suspending .said 'supporting bar; means for attaching the load to said lever .bargnand a'throwoff lever pivotally connected to one'flink-and adapted to .engagetheother link to hold one catch pin outo engagement whilethe .other is in engagement. j

y5. A `lifting jack comprising, a suspended vsupporting bar, said 4supporting bar .consistingfof amiddle two edged rack .bar and two vparallel guidebars .in .spaced relation to the .edges .of the rack `loar; a catch :acting along `:and in engagement Ywith vveach of the two.

notched ,edges .of said .ra-ck bar between said guide bars and said rack bar; .a .lever bar; links operatively '.connectingsaid catches to said lever bari; means for suspending .said

, supporting .bar and ,means for attaching the load to said lever bar. I

.6. .A ilifting jack comprisingasuspended' supporting bar, said supporting bar consistsaid lever bar; means for suspending said ing of a middle two edged rack bar and twO supporting bar; means for attaching the 10 parallel guide bars in spaced relation to the load to said lever bar; and means for operedges of the rack bar; a catch acting along ating the catches to step the load down- 5 and in engagement with each of the two wardly.

notched edges of said rack bar between said In testimony whereof I have signed my guide bars and said rack bar; a lever bar; name to this specification. v links-operatively connecting said catches to WILLIAM CLEMENS.

Copies of this 'patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.

Images