US2770339A - Lever hoist - Google Patents

Description

O. E. DOTSON LEVER HOIST Filed March 30, 1953 :F :rgj l Nw., 13, 1956 o. E. Do'rsoN 2,770,339

LEVER` HoIsT Filed March 30, 1955 3 Sheets-Sheet 2 :FFIIQJL 8 Ivg;

IN VEN TOR. Orr/'e E" Do zson A TTO/QNEV O. E. DOTSON LEVER HOIST Nov. 13, 1956 3 Sheets-Sheet 3 Filed March 30. 1953 INVE ,Orr/'e E. D0

A ORA/Ev United States Patent O LEVER HOIST Orrie E. Dotson, Lisbon, Ohio, assignor, by mesne assignments, to The Atlas Plastic Mold and Bre Company, Cuyahoga Falls, Ohio Application March 30, 1953, Serial No. 345,656'

Claims. (Cl. 192-16) This invention relates to a hoist and more particularly to a lever hoist.

The principal object of the invention is the provision 4of a lever hoist capable of advancing and holding the tensioning element thereof in any desired degree.

A further object of theinvention` is the provision of a lever hoist of relatively simple constructionincorporating a novel clutch and brake means.

A still further object of the invention is the provision of a lever hoist of lightweight, compact construction capable of being used for tightening cables and the like.

A still further object of the invention is the provision of a lever hoist which may be easily controlled and operated.

The lever hoist disclosed herein is particularly advantageously employed in lifting various objects relatively short distances and holding the same in desired position while the article is assembled into a `machine or the like and' wherein it is necessary to exactly control the vertical position of the article by moving it upwardly or downwardly a fraction of an inch.`

Various Llever hoists heretofore known in the art have had the common Ifailing of inaccurate close adjustment specifically in that the article being lifted or pulled by the lever hoist could not be accurately posititioned within the area defined by the spacing of the ratchet teeth of the hoist which controlled the braking effect thereof. On the contrary, in the present invention minute upward or forward adjustments may be made and minute down or backward adjustments are equally easily accomplished enabling a most precise location of an article to be realized through the use of the lever hoist.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being the invention to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention is illustrated in the accompanying drawing, wherein:

Figure 1 is an end View of the lever hoist.

Figure 2 is a side view of the lever hoist.

Figure 3 is an opposite end view of the lever hoist with respect to Figure 1 and with portions broken away.

Figure 4 is an enlarged sectional elevation of the lever hoist.

Figure 5 is a vertical cross section taken on line 5-5 of Figure 4.

IFigure 6 is a vertical cross section taken on line 66 of Figure 4.

Figure 7 is a vertical cross section taken on line 7--7 of Figure 4.

Figure 8 is a vertical cross section taken on line 8 8 of Figure 4.

By referring to the drawings and Figures l, 2 and 3 Mice in particular it will be seen that the lever hoist comprises a body member 10, the interior of which is hollow and one end 11 of which is of reduced diameter with the opposite end thereof dened by a plate 12. A circular boss 13 is positioned on the upper portion of the body 10 and receivesa hook 14. Openings 15 in the lower portion of the body 10 and beneath the hook 14 provide entrance and-exit passageways for a chain 16, one end of which terminates in a swivel 17 carrying a secondary hook 18.

The reduced end 11` of the body 10 forms a bearing for one end of a driven shaft 19 as may best be seen in Figure 4 of the drawings. The other end of the driven shaft 19 extends through the plate 12 and is engaged by a nut 20 threaded thereon and by means of which the plate 12 is maintained in position on the body 10. An annular ball bearing assembly 21 positioned within the hollow body 10 serves to carry the middle portion of the driven shaft 19 at a point thereon adjacent a sprocket 22 over which the chain 16 is positioned. The chain 16, and the sprocket 22`form the means of conveying motion of the driven shaft 19 to the article to be moved.

Means for driving the driven shaft 19 comprises a member 23 which `takes the form of a circular apertured disc with ratchet teeth 24 formed in its periphery. The aperture in the member 23 is provided with a` thread pattern 25 which registers wtih a thread pattern 26 formed on the driven shaft 19. There is sufficient area within the hollow body 1t! to permit the member 23 to rotate in limited degree on the thread pattern 26, which action causes it to move from right to left thereon, as seen in Figure 4 of the drawings.

In order that rotating motion may be imparted to the member 23, a handle 27 is rotatably mounted on the body member 1t] and retained in such position bythe plate 12, heretofore referred to. The handle 27 includes, in addition to the elongated handle portion and circular end section pivoting` on the body member 10, a longitudinally movable latch 28 spring urged toward the ratchet teeth 24 of the member 23by a coil` spring 2'9 positioned in a cutaway portion 30 of the handle member 27.

The opposite end of `the latch 2ti`has` an odset secondary handle 31 thereon as may best be seen in `Figure l of the drawings so' that the latch 28"may be` rotated `on` its longitudinal axis to move it into and out of engagement with Ithe ratchet teeth 24 on the member 23 and to reverse its effective ratchet-like engagement with said ratchet teeth 24.

The longitudinal movement of the latch 28 is occasioned by the presence of a pair of bosses: 32 on the handle 27 adjacent the secondary 'handle 31.

Positioned on the driven shaft 19 between the thread pattern 26 and the bearings 21 there is a sleeve 33 with a cam disc 34 rotatably mounted thereon and'a pair of discs 35 and 36 positioned one each on either side of the cam disc 34. The cam disc 34 and the discs 3S and 36 on either side thereof are positioned adjacent the inner face of the member 23 and so that upon its being moved into engagement with the same by rotation on the thread pattern 26 by the handle 27, it will lock the assembly together by frictional engagement against an annular ange 37 on the driven shaft 19 so that motion imparted to the body member 23 will be conveyed through the fric- -tional engagement of the discs 35, 36 and the cam disc 34 with the ange 37 of the driven shaft 119 and the driven shaft 19 thereby revolved.

The cam disc 34 has a plurality of cam slots 38-38 therein with rollers 39-39 mounted in the cam slots. The cam slots are arranged as shown in Figure 7 of the drawings to permit the cam disc `to move in only one direction as movement in the opposite direction causes the rollers 39 to move outwardly of the cam slots 38-38 and into engagement Wi-th an annular ring 40 which iS mounted within the hollow body member and keyed thereto as by a pin 41.

lIt will thus be seen that the driven shaft 19 with the sprocket 22 may be moved in one direct-ion by corresponding movement of the member 23 as imparted to it by the handle 27 as the member 23 moves inwardly on the thread pattern 26, engages the discs 34, 3S and 36 and locks them tightly against one another and the flange 37 on the driven shaft 19 to convey rotary motion of the member 23 to the driven shaft 19 and the sprocket 22. Thus, an article attached to the secondary hook 18 on vthe chain 16 will be moved toward the lever hoist in a lifting or tightening operation.

The cam disc 34 revolves during this action, the rollers 39 moving inwardly of the cam slots 38 and out of engagement with the annular ring 40. Immediately such motion stops, and a reverse or opposite motion commences, the rollers 39 move outwardly of the cam slots 38 in the Acam `disc 34, engage the annular ring 40 and lock the assembly thus securely holding the object on the hook 18 in any desired location or degree of tightness.

When it is desired to release the driven shaft 19 so that the sprocket 22 will permit the chain 16 to slacken and lower or release tension on an object attached to the hook 18, the secondary. handle 31 on the latch 28 is moved to reverse the position of the latch 28 so that the handle 27 may be used to move the member 23 away from the cam disc 34 and its adjacent discs 35 and 36 which will free the same from the driven shaft 19 thus leaving the driven shaft 19 free to revolve. As long as the latch 28 is engaged in the ratchet teeth 24 of the member 23, the reverse motion of the driven shaft 19 will be directly controlled thereby.

If it is desired to permit the chain 16 and the hook 18 thereon to fall freely or move away freely from the lever hoist, then the latch 28 is completely disengaged from the ratchet teeth 24 and the member 23 is capable of rotating in the hollow body 10 along with the driven shaft 19.

It will thus be seen that the several objec-ts of the invention are met by the lever hoist disclosed herein.

Having thus described my invention, what I claim is:

l1. In a lever hoist, a hollow body member having oppositely disposed aligned openings, a driven shaft located therein and journaled therein midway between said openmgs and in one of said openings a sprocket and an annular flange secured to said driven shaft and a thread' pattern formed on said driven shaft, said sprocket, annular llange and thread pattern positioned in spaced relation to one another, a cam disc rotatably positioned on said driven shaft between said annular flange and said thread pattern, and a secondary body member engaged on said thread pattern, an annular ring within said rst mentioned body member about said cam disc and spaced with respect thereto, a plurality of cam slots formed in the periphery of said disc and a plurality of rollers located one in each of said cam slots for engagement with said annular ring when moved in one direction, means for rotating said secondary body member, said secondary body member being capable of limited rotation on said thread pattern on said driven shaft to engage said cam disc and move the same against said annular flange to move the driven shaft and sprocket in another direction.

2. The improvements in a lever hoist set forth in claim 1 wherein one of the oppositely disposed aligned openings in the body member is provided with'an apertured cap, the driven shaft extending through the apertured cap and wherein a secondary thread pattern is formed on the driven shaft and a nut engaged on said secondary thread pattern to `secure the said apertured cap to the assembly.

3. The `improvements in a lever hoist set forth in claim 1 wherein the means for rotating the secondary body member comprise a plurality of teeth formed in the periphery of said secondary body member and a handle with a ratchet rotatably mounted on said body member and selectively engageable with said teeth.

4. The improvements in a lever hoist set forth in claim l wherein the annular llange and the sprocket are separate members provided with keyways and wherein said driven shaft is provided with a keyway and a key is positioned in said keyways to position said annular flange and sprocket in non-rotatable relation to said driven shaft.

5. The improvements in a lever hoist set forth in claim l wherein the annular ringl about said cam disc is formed as la separate element secured in said body member against rotation.

References Cited in the file of this patent UNITED STATES PATENTS 1,919,754 Sejersen July 25, 1933 2,083,954 Kessler June 15, 1937 2,403,462 Schroeder July 9, 1946 2,453,581 Moore Nov. 9, 1948

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