US1821737A

US1821737A - Lifting jack

Info

Publication number: US1821737A
Application number: US349934A
Authority: US
Inventors: Bootz Eugene
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-03-26
Filing date: 1929-03-26
Publication date: 1931-09-01
Anticipated expiration: 1948-09-01

Description

sept. 1, 1931. E BOOTZ 1,821,737

LIFTING JACK Filed March 26, 1929 2 sheets-sheet 1 2 Shets-Sheet 2 Sept. l, 1931. BOOTZ LIFTING JACK Filed March 2e.' 1929 31u/vento@ a f n /MV 7 @/0 7 f0 v A o a 7 f fio Patented Sept. 1, 1931 EUGENE BooTz, or DENVER; COLORADO' I 1 .tirarme f JACK rApplication filed March' 26, 194.29.- Seria1`No.-349,934.

rhis invention relates to improvements .in lifting jacks and has reference more particularly to a lifting jack'of the type employed in connection with automobiles and other ve-Y l5 hicles. v l Y l It is customary at thepresent time to attach to the Jfront and rear ends of automobiles, bumpers whichfproject a considerable rdis- ,w tance to the front of the front axle and to rear `10 of the rear axle. These bumpers'form; obstruc- Y tions which make `it diiculttoplace an`ordinary lifting jack under the axle for the purpose of raisingV the aXle whenever thisrbe- M comes necessary. Due to Ythe' great' distance "51115 from the bumpers to the aXles,it is'necessary in order to place an'v ordinary jack under the theground,v as only in vthis Y c, f i y Havmgthusbriefly describedthe inven-k axles, to lie flat on manner can the jack be placedv and-operated. ln order to overcome this objectionable feature, various jacks have been inventedwhich are operated by means ot long handles that make is ypossible to put thejack inr place and to operate it from a position front of the trontbumper 'or inl the' rear of the rear bumper. Y f 'l It is the object of this invention to produce a jack of asimple and substantial construction thatrshall be so mad'efthat when it i'sin proper -rposition to ot an automobile, it willbeentended so that it can be shoved into'place and Vwhich is opera-ted by means of a fall and tackle, the rope c formin the fall beingof such length that the person operating the jack can-stand in a vcomfortable position while pulling thesame.

This invention, briefly described, comprises a. base which is adapted to 4rest upon the tubular post within which is slidably arranged a sleeve within whichl a bar is televscopically mounted. The upper lendofthis liar' is provided upper end 'ofthe sleeve isprovidedwith a casting having an opening through which the bar projects. rihis casting has a pawl which serves to hold the bar in 'eiitended position. The casting at the upper endfof the sleeve is moved towards andaway from' the Vbase'by e means comprising two lazy'tong structures 50 one of these tongs bein-glocated oneachiside be inserted underl the axle Fig. 1 ;f`

Ground and which hasan upwardly extending with a lifting head' andthe 1 lof the tubular memberfand has one corner" pivotally connected to lthe base, while the other is pivoted to the cast-ing onthe upper endrofthe sleeve. `The end linksiof the'lazy tongs are connected by means of pulley blocks,5,5 each ot which is provided with two or more pulleys- These pulleys are interconnected by meansof a rope in the manner of a fall andV tackle so 4that when ,orce'is applied to the rope,v the lazy tong` structures will be col-90 lapsed thereby spreadingthe vertices and lraising the sleeve'upwardly in the tubular member. .'Means is ralso provided for hold-fy ing .the rlazy'tong structures against both upward and vdcmfnward movement and for latch-Q5 ing the rope'so as to hold the jack in any desired position. j f V vtiem-the same will now; be described in deposition.;y

jFig; 2 isa top plan" view of the jack parts being shown-in section;

Fig. 3.a,is a .section taken online 3 3,

Fig. l'is a section taken on line #4, Fig. l;

Fig. V5 is a section to a somewhat enlarged scale', takenonline 5-5, Fig. 2; and 1 -Fig. 6 is a section taken on line 6-6, Fig. 5;andV 'K 5 Fig. 7 is a section taken fon line 7-7, Figy.` i V In .the drawings reference numeral 1 designates a base which is adapted to rest upon the ground, or any otherv supporting surfacegggo 'Thisbasehas `been shown as of rectangular shape and considerably longer nthan it is wide.

A tubular post 2 extends upwardly from the .center of the base and is preferably formed integral therewith. On each side of post Z395 are two upwardly extending spaced lugs 3, which are provided with perforations for the rivets or bolts, 4 thatiiform the pivot for the links of the lazy tong devices which are employed.y for, raising and lowering the-jack;-

s Fig.`5, the bar 8 may of within the and which will be hereinafter described. Located within the post 2 is a` sleeve 5, which is provided at its front and rear with slots 6 whose purpose will hereinafter be explained. Secured to the upper end of sleeve 5 and preferably formed integral therewith is a head 7 which is provided with an opening that forms a continuation of the openingin sleeve 5. A bar 8 which is provided on one side with a plurality of ratchet teeth 9 is telescopically mounted in sleeve 5. The upper end of bar 8 is provided with a lifting head 10, that is adapted to engage the automobile axle or the under surface of any thing that is to be lifted by means of the jack. The head 7 is provided on opposite sides with downwardly extending ears or lugs 11 cor@ responding to lugs 3 on the base. These lugs are provided with openings for the reception of pivot pins 12 means o f which the links of the lazy tong devices are secured to the head. of head 7 to the otherl and forms a pivot for Apin 13 extends from one side a pawl 14 which is provided with two handles 15 that straddle the tubular member 5 in the mannersho'wn in Figs. 5 and 6. When the bar 8 is to be lowered within the tubular Vmember, handles 15 are raised upwardly so as to release the pawl. The lower end of Abar 8 is split and is provided with a small pulley 16 that is attached to it by means of a pivot pin 17. A cord or steel cable 18 has one end anchored to the head 7 at 19 and extends A downwardly aroundthe pulley 17 and thence upwardly and passes over a pulley 20 pivot- Vally attached to'head 7 in the manner shown in Fig. 5. When tension is applied to this cord of rope in the direction of the arrow in be moved upwardly sleeve and in this manner the height of the lifting head 10 can be adj usted i to lit the height of the axle orother article that is to be lifted. For the purpose of accommodating the cord 18, post 2 is provided with slots 21 in the manner shown in Fig. 5.

The mechanism for operating the ack will now be described. This mechanism consists of two lazy tong structures, each of which consistsof two groups A and B of links 22, which are pivotally connected atl their middle points as indicated by reference numeral 23. 'The ends of one of these pairs of llinks are pivotallyA attached respectively tothe base and to head 7 by means of

pivot pins

4 and 12. Pivotally attached to

pins

4 and 12, are short links 24 whose other ends the pulleys 28. A bolt 29 serves as the pivot about which the pulleys rotate. The pulley block `26 is provided with a handle or loop' 30 for convenience in extending the lazy tong.4 It will be seen from Figs. 2, 3 and 4 "that there are two lazy tong assemblies of als are employed to indicate the corresponding elements of each of these assemblies. Pivotally attached to the free ends of the linkscomprising pair A are short links 31, whoseouter ends are connected by means of pivots with the pulley block 33. Pulley block 33 is substantially identical with block 26 and differs therefrom only in minor details and will therefore not be described, except for the purpose of calling the attention to the differences. From Fig. 3 it will be seen that pulley7 block 33 is provided with an upwardly extending lug or ear 34 through which the pivot pin 32 extends. A pulley 35 is pivoted on the pivot pin 32 adjacent one side of the pulley block. Both of the

pulley blocks

26 and 33 are provided on each side with inwardly extending lingers 36, which serve as guides for the pivot pins 37 that connect the vends of the auxiliary links 38. The other ends of these links are pivoted at 39 and 40 to links 31 and to the links 22 that are pivoted to the base and to the head 7. A rope 41 forms the fall ofthe tackle and when force is applied to the free end of this rope in the direction of arrow 42, the pulley blocks will be moved towards each other, thereby,v collapsing the lazy tong devices. It is obviing the number of these link assemblies, a

multiplication of force is thereby obtained. The power of the jack with a certain number of pulleys can therefore be varied by varying the number of link assemblies. It is also evident that as the link assemblies approach collapsed position, their toggle actions will increase as this varies with the size of the angle designated by W.

The operation of the jack is as follows: When the jack is to be used, it is extended until it occupies the position shown in Fig. 1. This'brings the head 7 downwardly towards the base. The jack is now inserted and put in place underneath the axle or other object to be lifted. The operator then pulls cord 18, thereby raising the bar 8 upwardly until the head 10 engages the object to he lifted. Force is now exerted on the free end of rope 41, thereby movin@1 the

pulley blocks

26 and 33 towards each other, whereby the head 7 and bar 8 with its attached head 10 will be moved upwardly, so as to lift the automobile axle or other object. After the object has been raised to the extent desired,

rope 42 may be clamped in the notch 43, which serves to latch the rope although this is not as a rule necessary when the lazy tong devices areentirely collapsed as the friction of the parts is sufficient to maintain the parts in collapsed position with any ordinary load.

In the above description a specilic embodiment of the invention has been described in order to illustrate the construction. It is my intention, however, to construct the jack entirely from soft steel bars and plates that can be readily shaped by means of dies instead of using castings and to arrange the pulleys 15 28 so that they will rotate about horizontal instead of about vertical axes. It is also evident that the end links 24 and 3l may have common pivots 25 and r32 for each pair of links instead of having two spaced pivots 25 and two spaced pivots 32. Handles 30 can also be replaced by chain loops.

From the above it will be seen that I have produced a lifting jack of a simple construction that is especially well adapted for use in connection with automobiles as it can be readily put in place and removed and which can be cheaply constructed, owing to the fact that most of the parts are duplicates.

Having describedrthe invention what is claimed as new is: i

l. A lifting jack comprising, in combina- 3. A lifting'jack comprising, in combination, a base adapted to rest upon a supporting surface, a lifting head slidably connected with the base so that it may move towards the head and base will approach each other and when the tong is shortened the head will be moved away from the base, a plurality of pulleys attached to the links at the opposite ends of the tong and a rope encircling the pulleys to form a fall and tackle.

In testimony whereof I ailix my signature.

EUGENE BOOTZ.

tion, a base having a standard projecting n from one side thereof, a bar slidable on the standard, a lifting head secured to the upper end of the bar, a lazy tong structure comprising a plurality of sets of links-pivotally connected at their centers and having the adi acent ends of each pair pivotally connected, the links of each end'pair being pivotally connected to the ends of shorter links, pulley blocks connecting the other ends of the shorter links, the pivot between one of the long links and one of the shorter links being connected with the base, the opposite correspond ing pivot of the lazy tong being connected with the lifting head and a rope cooperating with the pulley blocks to form with the latter a fall and tackle.

2. A lifting jack comprising, in combination, a base adapted to rest upon a supporting f surface, a lifting head slidably connected' with the base so that it may move towardsv y and away from the lat-ter, and means for moving the head with respect to the base, said means comprising a lazy tong composed of a plurality of sections of crossed links, the end of one link of one pair of links being connected with the base and the end of the other link of the pair being connected with the head whereby when the tong is extended the head and base will approach each other and when the tong is shortened the head will be moved away from the base and means comprising a fall and tackle device for collapsing the tong.