US1829662A

US1829662A - Lifting jack

Info

Publication number: US1829662A
Application number: US297239A
Authority: US
Inventors: William F Krenzke
Original assignee: Walker Manufacturing Co
Current assignee: Walker Manufacturing Co
Priority date: 1928-08-03
Filing date: 1928-08-03
Publication date: 1931-10-27
Anticipated expiration: 1948-10-27

Description

o 3 w. F. KRENZKE 1,829,662

LIFTING JACK I Filed Aug. 5, 1928 2 Sheets-Sheet 1 M j 1 if OTTEQE Oct. 27, 1931. w. F. KRENZKE LIFTING JACK Filed Aug. 5

2 Sheets-Sheet 2 35 lifting members.

" lng' member 'carrl Patented 27,

asarolon 'ro wanna mamamo 001mm; A oonrona'rr'ou'or wrsoom ammo no:

' A turias me an: a, m. 'urm 10.897).

This invention relates t'o' new and useful improvements in lifting Lacks, and more par-' ticularly to a screw ac not: the double exjtension type, design to have a long lift in 5 proportion to the sim and height of the jack when in lowered or collapsed position. 7

The jack is of that type. employing a plurality of telescopically engaged 'ftmg and guide members, certain of which have screw 1 threaded driving connections with one another, and others being keyed-together to permit vertical sliding movement without permitting relative rotatio'm The general ob'ect of this invention is to as provide a jack 0 ,this' type,-fas disclosed in etail hereinafter, which is capable of a maximum elevation inproportion to the-ilk itial height of the jack andz the number of telescoping members Y m'g gear mounted inthe lower end of the supportin standard, so that the power may be most e ectively applied, while at the same time permitting a maximum lowering'of the Another obiect is to rov ide an improved form. of sheet'metal gui e-sleeve.

Another object is to provide-means for causing the guidesleeve to be elevated with the upper lifting member until the guide sleeve'has reached its. maximum elevation. Another object is to rovide a jack of this type which is simple and economical to manulecture, and easily assembled. j Other objects and advantages ofithis invention will be more apparent from the following detailed description of one approved .form of the mechanism,

Inthe accompanying drawings:

' Fig. 1 is a pe tive elevation of the completely extendeii jack. M Fig. 2 is a central vertical section through the jack,..when extended, as shown in Fi 1. '-'-F1g. 3 is a, similarcentral vertical section, showing the jack completely lowered. Fi 4 is -a horizontal section, taken substantlally on the line of Fig. 3;

Fig: 5 is a detail perspective, on a la r;

scale, of the drivin gear and tubular du thereby.

'tion 50 r The supporting standard comprises a suitablebase plate 1, and a'hollow standard 2 which may be made of malleable iron, or of. Y ressed steel. parts suitably assembled. tandard 2 comprises an enlar lower end rtion 3 havin aniout-turn end flange 4 y means of .w ich the standard is secured to base late 1. The smaller upper end orstandard 2 is inthe form of a c'y lindrical guide portion, ha a vertical proection 6 at one sidewhich ouses the verti' cal guidegroove 7. An outwardly extend ing and upwardly inclined tubularbearing 8 ormedjn one side wall of standard 2 intermed ate its upper and lower ends, receives 1 the ournal 9 of the driving pinion 10. -A han wheel or disc '11, for conveniently rotat- .ing the driving pinion,'is mounted on the outor end of ournal 9, and a non-circular socket Another object is to provide a cupp d driv- 12 in journal 9 is adapted to receive the correspondm ly aha dend of adri handle, who by t e jac may be operafi from a distance when lifting or lowerin the load'.

The improved driving gear (s own in' per- 'spectlve in Fig. 5) comprises a base portion 75 or disc 13, from which arise the vertical substantially cylindrical side walls 14. 'An inwardly' extending fiange 15 at the u per end of cylindrical portion 14 is 'formed with an annular series of gear teeth 16 adapted to mesh with the driving pinion 10. The lower outer edge portion of this gear member is meet or curved inwardly, as indicated at 17,- to housethe members of an annular roller bearing 18. This bearing comprises lower race-way 19 carried by base late 1 and center'ed by engagement with t e lower end of standard 3, and an upper race-way 20 centered in the annular depression 17 in the gear. member. In this manner the gear member is rotatably supported from the base 1, and centered within standard 2, with the base portion '13 of the' gear positioned :-as closely as possible to the base plate 1 and the cylindrical outer walls 14 of the gearmember closely adjacent the side walls of standard 2, sothat I the'lifting members, hereinafter described,-'

may be telescoped within the gear member with their lower edges brought into'close PTO. or o the base s of the ear,- a no closely as maximum owering of the ssible to base plate 1, whereby a ifting members is made possible.

A, hollow tubular driving member 21' is mounted at its lower end in base 13 of the of. A stop 25 secured in the lower end portionfl ofscrew 23,. is adapted to engage the lowenend: of threads 24 to limit the upward engagesthe inset portion at the upper movement of the screw.

An enlarged head 26 exteriorly threaded at 27', iskeyed on the upper end of screw 23, as-indijcated'at 28. An upper tubular liftmember 29 is interiorly threaded at 30 to receive the head 26. The upper end of lifting member 29is(provided with 'a suitable loadengaging hea or plate 31.

ide sleeve 32 is preferably formed of sheet material: bent to formahollow cylindrical portion which will fit telescopically within the upper cylindrical end '5 of standard"2,*and-a vertical hollow rib 33 adapted to slide within the groove 7 in the standard.

This ribmay be conveniently formed by bending-outwardly the walls of the sleeve, as indicated'at 34 and 35, and then bending toward one another and overlapping the

ends

36 and 37 of the sheet from which thetube is formed; These overlapping wall portions may be united by welding, or by rivets, as-indicated at 38 and 39. As here shown, the

lower rivet 38 serves as a stop member, which endof groove {of the standard for limiting the upward movement of sleeve 32. It will be apparent that the engagement of rib 33v within the groove .7 in the standard will. prevent relative rotation between the guide sleeve 32 and the standard, and an outwardly cylindrical Surface of 1i g e 29 r -me extending projection 41' onthe'lower end of the uper lifting member 29 slides in the V groove 42- formed in. hollow rib 33 so asto prevent relative rotation between the sleeve 32 and lifting member 29. Since the sup-'- porting standard is held from rotation by its engagement with the ground or other supporting surface, it will be apparent that the' upper lifting member 29, which supports the load,.is'never permitted'to rotate. I A spring latch 43 is mounted in the upper rtionofgroove '42 in sleeve 32, as by means of the rivet. 39. The finturn'ed finger--44 at the upper end of spring latch 43 is adapted to detachably engage .in a notch 45 formed ad acent the upper end of lifting member 29.

The latch is shown in engaged or latching position in Fig. 3. v

When the jack is completely lowered, as shown in. Fig. 3, all of the lifting and guide members will'be completely housed within the standard 2. 'It will be noted that the screw 23 can be made of iajmairimum length so as to extend completely down to the base plate 1. The guide sleeve 32 and upper liftmg'member 29 telescope-down= over'1thetubu- I lar driving member 21, and'withinthe cu shaped gear member so as to-extend at their lower ends closely adjacent the base 13 of th'gNgear.

hen the driving pinion is rotated in the proper direction for elevating the jack, the. lifting screw 23 which is held from rotation,

due to its engagement with upper lifting tional resistance between the threaded head 26 and the internally threaded liftingmember 29 than there is between the screw 23 and the'nut 24) will bejelevated through the nut it will be forced to rotate with'the tubular.

driving member 21, thus rotating head 26 with n theupper lifting member 29 andicausing that member to be raised out of guide sleeve 32. When furtherupward movement ofguide sle'eve 32 is prevented by thestop. '38 engagmg the. stop 40 on thev standard, the

spring latch 43 willsnap out of the notch '45. and permlt the lifting member. 29 to move upward to the extreme position shown in Fig. 2, where further elevation of thejack mem- I hers is prevented by theen agement of projection 41 with the lower en of latch member 43. During this latter movement oflifting member 29, the finger44 on spring latch 43 Wlll. simply bear yieldingly against the outer The jack 'is again lowered by alreverserota tion of the driving pinion,..and';-when the member 29, (there usually being greater fric-,

members have been completely :telescoped ber 29, as shown in Fig. 3.

By providing means for causing gtlie sleeve 32 to be elevated duringthe [first half of' thef load-lifting op ration, the lifting members are additionally stifiened during this phase of the movement,% and' the sleeve 1. In a lifting'ieckye sibi iit isias within the standard, the springjlatch 43 will gain snap lntothe notch45in lifting mem- 5 in gear consisting of a horizonta base, a

su stantially cylindrical portion arising therefrom adjacent the innerside walls of the standard, and an annular series of gear teeth formed at the upper end of the cylindrical portion and-adapted to mesh with the driving pinion, an annular bearing inset in the outer edge portion of the driving gear for supporting same from the base plate with the gear base positioned closely ad acent the base plate, an upright ,hollow c lindrical driving member mounted central y in the gear baseand secured thereto, the upper end portion of this member being interiorly threaded, a lifting screw meshing with these threads and adapted to telescope within the driving member, an exteriorly threaded head 'on the upper end of the screw, a hollow interiorly threaded lifting member in which the head meshes, a hollow ide sleeve formed with an outwardly projecting hollow vertical rib atone side thereof, the up r ortion of the standard being formed to slidably receive the sleeve and rib, the lower end of the lifting member having a' projection thereon adapted to slide vertically in the hollow rib, sto' members on the standard and sleeve, an .a spring latch mounted in the upper portion of the hollow rib of the sleeve and detachably engaging the lifting member so that the sleeve will be carried up with the lifting e engagement of standard carried thereby, a driving pinion mounted in one wall of the standard, a horizontally disposed drivin gear meshing with gear from the base plate, a tubular vertically extending driving member mounted centrally on the driving gear, the tubular member being interiorly threaded at its upper end, a lifting screw threadedin the tubular member, an exteriorly threaded head mounted at the top of the lifting screw, a hollow interiorly threaded lifting member in which the head meshes a hollow guide sleeve telescopically engaging the standard and the hollow liftin member, there being slidably interengage fportions on the sleeve, standard and lifting member to prevent relative rotation of these members, a stop for limiting the upward movement of the sleeve, and a spring latch detachably connecting the sleeve and lifting member so that the sleeve and lifting member will be elevated as a unit until the the sleeve.

3. In a lifting jack, a supporting member standard carried thereby, a drivin on the comprising a base plate and a hollow upright the pinion, a hearing. or supporting the comprising a base plate and a hollow upright pimon mounted in one wall of the standar a horizontally disposed driving gear meshing with the pinion, a bearing for supporting the gear from the base plate, a tubular vertically extendin driving member mounted centrally driving gear, the tubular member being interiorly threaded at its u per end, a lifting screw threaded in the tu ular member, an exteriorly threaded head mounted at the top of the lifting screw a hollow interiorly threaded lifting member in which the head meshes, a hollow ide sleeve telescopically engaging the stan ard and the hollow lifting member, there being slidably interengaged portions on the sleeve, standard and lifting member to prevent relative rotation of these. members, stop members on the sleeve and standard for limiting upward movement of the sleeve, and a spring latch mounted in the upper end of the sleeve and detachably engaging the lifting member so that the sleeve will be carried up with the lifting member until further upward movement thereof is prevented b the sto members.

.4. In a lifting jaclz, a hol ow standard formed at its upperend with a cylindrical portion with a vertical guide groove rojecting outwardly from one side thereo a hollow cylindrical guide sleeve formed with a hollow longitudinal rib rojecting outwardly therefrom and slidab y received in the groove, a cylindrical lifting member telescopically received in the sleeve and having a projection on its lower end portion slidable in the hollow rib, and means mounted in the standard and engaging the lifting member for raising and lowering the sam 5. In a lifting jack, a hollowstandard formed at its upper end with a cylindrical portion with a vertical guide groove proilectmg outwardly from one side thereof, a ollow cylindrical 'de sleeve formed with a hollow lon 'tudinalrib wardly there om and slida 1 received in the. groove, a cylindrical lifting member telescopically received in the sleeve and hav-. mg a projection on its lower end rt-ion slidable in the hollow rib, stop rs on the standard and sleeve, and a spring latch rojecting out mounted in the hollow rib and detachably the standard and engaging-the lifting her for raising and lowerin the a 6. In a lifting jack, a ollow'standara formed at its upper end with a cylindrical portion with a vertical guide groove'fprr; 'l:::,t, stop-prevents further upward movement of a: L

ing outwardly from one side theneo A low guide sleeve formed of sheet metal to form a cylindrical portion and an oute engagement of H I vard1y' ;-extending hollow vertical rib, the edgedof the metal sheet beinfi) overlap iei;

to-form the outer well-of the n the rib -.ing slidahly received in the groove ofthe .5-standa-rd,' a, cylindrical lifting member tele scopically received in the sleeve and having 1 a rojection on its lower end portion slidab e in the hollowrib, and means moun in the standard and engaging the 0; member to raise and lower the same.

AM F. KRENZKE.