US1794798A - Jack - Google Patents

Description

March 3, 1931. El E. sARR 1,794,798

JACK

Filed May 2, 1927 v REL \\\\\\\\\\\\\\\\\\\\\\\www!Illillllllllllllllllllllllll 9,3 Elma-r1 E. '5a-rr' UNE Patented Mar. 3, 131` Eni/inn i E. `SARR, or HURON, OHIO,

rres PATENT or-ice ASSIGNR F NE-HALF TO I-IIRALI C. WEITZMAN,

OF I-IURON, OHIO.

JACK

Application filed May 2, 1927'. -SerialvNd 188,347.

The present invention relates to improve-y ments in jacks, and the primary object of the invention is to provide an improved typeof jack primarily intended for use in connection with the legs of furniture such astables of Vvarious characters, chairs, and the like,

for use as a leveling means therefor.

A further object of the invention is to proy vide a jack of the character set forth embodying an elevating means for causing the lift to travel in a perfectly parallel relation with respect to its base orsupporting section.

VA further objectief the invention isto prol vide an improved type of jack as setforth construction as to permit of the device being formed relatively shallow as to its over-al1 height.

A still further object of the invention is to provide an improved type of jack for use in connection with table legs and the like,em bodying novel features ofassembly and features of construction whereby the interiorfof the device isv rendered practically dust and,

moisture proof. Other obiects and advantages of the invennectionv with the accompanying drawing forming a part of this specification/and in which drawing:

Figure l is a central vertical section through the improved jack taken longitudi- 1 nally of the power screw and showing an element such Vas a table leg or the like supported n by the jack.

Figure 2 is a central vertical section through the jackonY the line 2-2 of Figure l and looking in the direction lof the'arrows.

Figure 3 is top-,plan view of the base section fof the jack and showing the `arrangement of the `lift or elevating means for movement of the capsection away from the base section.

' Figure l is a perspective view of the inner side ofthe cap or lift section and showing portions of the side wallsbroken away foi better illustrating the specific construction of the cap section.

Figure 5 is a perspective view of one of the wedge members of the elevating means.

Figure 6 is an enlarged fragmentary detail view of the power screw.

v Referring to the drawing in detail, and wherein similar reference characters designate corresponding parts throughout the J several views, the letter A designa-tes the base section of the jack, B a cap or lift section telelscopicallyassociated with the base section A, and C an elevating or lift means arranged` -in the base sectionA and acting upon the cap section B-for movement thereof in a parallel plane away from the base section A.y

Referring first to thebase section A, and

which may be cast from any suitable material such as brass', iron, aluminum or thelike, the` same in the vexample shown is square sli/'ape in plan and embodies aflat base platelO provided at each marginal edge with upstanding bordering side walls ll'.` Each of the side walls ll has reduced upper portions l2 which form an externally extending shoulder 13, while. the lower edge of each wall has aA flaringbase portionV 14 which projects fora short distance belowthefunder surface of the base platelO as.clearlyfillustrated in Figures l tion will be apparent during the course of the following detailed description, take in con-f andv 2 and which margin ally" extending Vba se 1portions will. provide a more uniform bearing y17 respectively, and whichribs as will be observedgin Figure 3 extend in parallel alignment with the power screw and from one end wall l1 to the directly opposite end wall.

`While not entirely essential it is preferred that the outerslide ribs 17 be disposed closely adJacent the opposite side walls 1l andk that .Yersely of :the tongues.

the inner ribs 16 be spaced but a short distance apart as illustrated in Figures 2 and 3. Formed on the base portion 14 of one of the side walls 11 directly below the shoulder 13, is an outwardlyv extending` boss 18 pro-vided with an opening or passageway V19 and which opening preferably is of elongated formation in cross section with the major cross section dimension of the opening extending v ertica'l'ly or at a right angle to the l'o-ngitndilllll axis of the side wall 11. Thus it will be seen that the base section A is of substantially box like formation and provides a pocket 2O opening at the upper side :of the b i; like section.

Referring now tothe cap or 2lift section B and which is also preferably .formed of cast metal of a suitable nature, the same is adapted to be telescopically associated with the :base s Vtion A and embodies a flat cap plate being recessed at its outer face and inwardilgief 'its marginal edges for pri-)vida` a depression or socket 23, and depezfid-ing from each marginal edge .of the cap plate, are ll-ordering flanges 2a of a depth substantially equal .tothe height of the reduced upper -portions 12 of the spaced side walls 11. As will lbe observed in .Figures 1 and 2, the inner sur faces of :the :depending iianges 24 slidab'ly ngage the outer .surfaces of the upsta-ndli-ng portions 12 Aof the base section A. This telescopical'ly lfitting of :the sections A and B serves to effectively exclude dust and dirt from entering `the pocket y2O. Depending from the under side of the ea-p plate 22 and preferably cast integra-l -with'tlie section B, a series of parallel spaced Aa1 ')ar-t tongues being of greatest depth at their longitudinal centers and tapering therefrom in opposite directioi-is toward the lflanges 24 for Afori-ning oppositely incl-ined guide surfaces and 27 with the guide surfaces of `the tongues aligning` one with the other tr-ans lon gitud nal l-y a rrai-l ged tions A and B are in assembled relation, extend in substantial longitudinal yaligni'nent abo-ne each of the slide ribs provided on the upper side ofthe base plate 10. 'It may here be well to state thaftrthe overlapping ofthe flanges 2li and wall portions 12 also 'acts as guide means for preventingrelative lateral shifting of the sections A and sl.

As ameans forretainingthesections A and B in assembled relation during shipment, it is preferred that relatively short screws 28 be threaded through oppositefianges 24 as in Figure 2 and have their inner ends movable in suitable elongated slot-S29 provided in the outer faces of the base wall portions 12. Those Screws 28 andslots .29 will permit of relative movement of .the soot-ions A and B but provost ,the Sections from boing .sopa

VThese tong-ues when ythe sec-Y .;able with the wedge members 32 and 34 for movement thereof toward and away from one another alpen .rotation of the screw. The

wedge members 32 and 34 are of substantially 'ident-ical construction and each embodies an clon-gated fiat tbottom portion '36 and an outer wall por-tion 37 which l extends along the outer longitudinal edge lof the bofttom portion preferab'ly in right angular relation therewith. Formed at the upper side of the bottom portion 3G vand inner side of the outer wall'pc 1tion3,-a-ie inner and outer wedge stri-ps 3S and -39 respectively each 'having correspondingly inclined `upper 'eel-ges l() which slope from 'the upper Yedge ofthe outer wall portion 37 towardthe inner edge ofthe 'bottom wall portion 36 as clearly 4 illflfustrated in Figures 1 and '5. The upper edge of the outer wall `-portion 37 is preferably inclined to correspond with the inclination ofthe edges 4 0, These wedge strips 38 yand 39 and when the wedge members are in position within the poeketw`20 are disposed above the respective slide ribs 16 and 17 and have their inclined V upper edges aligning with the guide surfaces 2 6 and 2 7 of the tongues 25. Thus it will 'be seen that .the friction caused by the fsliding action of the wedge members 32 and is materially decreased by the edge contact between the tongues '25 and wedge Vstrips 3 8 and 39. Sliding friction between 'the wedge members and 'base plate 11() is also decreased. by reason of the edge Contact of the -ri'bs 1 6 and 17 with the -nnder side of the wed-go .bottom portions 3 6. An arcuate shaped lug 42 depends from the. longitudinal center and inner edge of the bottom wedge portions 36 and extends between the inner L ide ribs 1 6 for reinforcement of itl- 1e medial por 'on of ithe wedges and also aiding lin presen ng later-al or longitudinal shifting ofthe wedge members.

' The only differing charactenistics lbetween i the wedge =members132 and 34, isthat the outer wall portion 37 of the wedge l n oember r311 is'provided between the wedgestrips 39 with a threaded opening 44 provided with left hand threads, While the outer wall portion 37 of the Wedge member 32 is provdd between the Wodgostrps 3 9 with fa` threaded opening t6 of loss diameter-man that of the openiiigi and provided with :right Lhaadtlireads mee-,ves

shank portion 48k being arranged at the terminal of the power screw and being of less diameter than that of the shank portion 47 which is arranged adjacent the head or operating end of the power screw. The shankA portion 48 of smaller diameter is provided with right hand threadsl for threaded connection with the right hand threaded opening 46 while the shank portion 47 of larger diameter than the shank portion 48 is provided with left hand threads for threaded engagement in the left hand threaded opening 44 of the wedge member 34. The right and left screw threads of the shank portions 48 and 47 respectively are of the same pitch so that upon rotation of the power screw each of the wedge menibei's 32 and 34 will travel atan equal rate of speed. Formed at the outer end of the shank portion 47 is a thrust collar 50 which bears against the inner side of the base section wall 1l at the inner end of the opening 19, and extending through the opening 19 from the collar 50 is a stem portion 51 which projects for a distance past the outer end of the boss 18 for receiving a suitable operating knob 52 preferably provided with a wrench square 53. Thus it will be seen that the boss 18 forms a bearing for the outer end of the power screw 35 and byv reason of the knob 52 engaging the outer end of the boss, the power screw 1s held against longitudinal movement when being rotated for movement of the wedge members 32 and 34. The opening 19 has been so formed to allow the ready insertion of the stem portion 51 through the opening from the inner side of the base section during assembly, and after which the knob 52fmay be connected with the projecting end of the stem. By so having the opening 44 of the wedge member 34` of greater diameter than the opening 46 ofthe wedge member 32, such will permit of the rcduced right hand threaded shank portion 48 to be readily inserted through the oppositely threaded enlarged opening 44 p for proper threaded connection with the right hand threaded opening ofthe wedge member 32.`

Thus it will be seen that upon rotation of the power screw that the wedge members 32 and f 34 may be drawn together or moved apart by thev power screw embodying right and left threads of the same pitch but of different diameters. By having the threaded portions 47 and 48 of the same pitch, it will be seen that the wedge members 32 and 34 will travel at equal rates of speed for movement of the traveler cap plate 22 in a perfectlyparallel position toward or away from the lbase plate 10.

` `l/Vhile the device is primarily intcn'ded'for useas a table jack, itl will readily be apparent that the device may beusedfor various other purposes where a wedging orv lifting action is tobe'performed. From the foregoing description it will be apparent that an improved andv novel type `.of jack has been `providedembodying rrelatively few and simple parts so arranged as to reduce the over all height to a minimum and winch-device'y operates under a novel principal' whereby the cap or lift section movesin a plane parallel with the supporting or` base section' of the device. f1 i Changes in the shape, rsize and arrangement ofY parts may be made to the specific form of the invention herein shown and de- `scribed,' without departing from the spirit of ing a hollow base section having a fiat bottom wall, a cap section slidably associated with the base sectionand having spaced narrow tongues'projecting into the hollow base section and provided with oppositely inclined guide surfaces, vwedge" members slidablyA mounted in the base section and engageable yone witlieach of the oppositely inclined guide surfaces of said tongues, and a power screw carried by the base section and having threaded connection with each of said wedge members for imparting equal degrees of movement thereto upon rotation of the power screw.

2. 'A jack of tlieclass described comprising a hollow base section, a cap section telescopically fitting over the base section and having parallel arranged tongues dependingfrom its under side and extending into the base section for providing oppositcly inclined guide surfaces, wedge members slidably mounted in the base section and each embodying wedge strips having inclined edges for aligning with and engaging the inclined surfaces of said tongues, and a power screw mounted against longitudinal movement in the base section and having threaded connection with said wedge members for imparting equal degrees of movement thereto in opposite directions upon rotation of the power ing a base section including a base plate andi 'side walls, slide ribs formed 1n parallel relation on the upper face of the base plate, a cap section telescopically fitting over the side walls of the base section and having longitudinally arranged tongues provided with oppositely inclined guide surfaces, ywedge Y members extending transversely of and resting upon said slide ribs and having' inclined upper edges engageable with the oppositelyl inclined guide surfaces of said tongues, and

a power screw mounted against longitudinal movement in one side wall of the base portion in parallel-alignment With-saidguide ribs and having threaded connection with each of said wedge members for movement of the members towardfandfaway tromione another upon rotation .of the power serew.

4. Ajaekof the :class `deseriloed comprising a hase section embodying aat base plate and .Oy upstanding side Walls, Aa cap section `embodying a recessed top plate having depending flanges engagealole -with the outer surfaces of said hase :section Walls .and integral longitudinally arranged tongues at y,the `under .side 1,15 ofthe top plate provided with oppositel-y inclined guide surfaces, .along rtheir loweredges said'tongues fbeing oai greatest height at their longitudinal centers and tapering towand the top plate opposite Harige portions thereof, Wedge members slidable on the flat hase plate,

each including a series of Wedge strips having inclined upper edges for surface contact with the oppositely inclined guide surfaces of said tongues, `said Wedge members extend- 25 ing trzansverselyfof said tongues, .and a power screw mounted against longitudinal movement iai-oneof the Side Walls -of the base portion and .extending in longitudinal relation with said tongues .and having Aportions for threaded connection with the Wedge members. for imparting equal degrees of Inovement thereto upon rotation of .the power Y screw.

ELMER E. SARE.

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