US2752205A - Sheet rock lift - Google Patents

Description

June 26, 1956 1.. u. WARD ET AL SHEET ROCK LIFT 2 Sheets-Sheet 1 Filed July 27, 1954 Fig.2

Lowe/l (J. Ward L 00119 J. Ward INVENTORS June 26, 1956 u. WARD ET AL 2,752,205

SHEET ROCK LIFT Filed July 27, 1954 2 Sheets-Sheet 2 Lowe/l U. Ward Louis J. Ward United States SHEET ROCK LIFT Lowell U. Ward and Louis J. Ward, Sacramento, Calif. Application July 27, 1954, Serial No. 446,128

3 Claims. (Cl. 304-29) This invention relates to a sheet rock lift and more specifically provides improved and novel construction of a sheet rock lift which constitutes a continuation in part of our copending application Serial Number 401,805, filed January 4, 1954, and now abandoned.

An object of this invention is to provide a sheet rock lift for raising and lowering sheet rock for positioning the sheet rock against a ceiling or overhead thereby enabling workmen to easily and etficiently position the sheet rock on the desired surface.

Another object of the present invention is to provide a sheet rock lift including a vertical frame member having a pair of vertical guides thereon for slidably receiving a pair of vertically moving lift members together with novel means for raising and lowering the lift members.

A still further object of the present invention is to provide a sheet rock lift including in its construction a pair of sprocket gears together with a sprocket chain passing thereover for raising and lowering each lift member wherein the lift member is secured to the sprocket chain.

Yet another object of the present invention is to provide a sheet rock lift conformable to the preceding objects wherein means is provided for adjusting one of the sprocket gears thereby adjusting the tension of the sprocket chain and the provision of two sprocket chains which are so related that they move in timed relation thereby raising and lowering a pair of lift members in unison.

Other important objects of the present invention will be found in its simplicity of construction, efiiciency in operation, its adaptability for various purposes and its relative inexpensive manufacture.

These, together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure l is a side elevational view showing the sheet rock lift of the present invention with portions thereof broken away to show the structural details thereof;

Figure 2 is an end elevation of the present invention with portions being broken away for clearer illustration of the structural details;

Figure 3 is a vertical sectional view taken substantially along a plane passing along the longitudinal center line of the device showing the construction thereof;

Figure 4 is a top plan sectional view taken substantially upon a plane passing along section line 44 of Figure 3 showing the relationship of the various sprocket gears together with the transverse shaft and the means for actuating the lift member;

Figure 5 is an enlarged side view showing the ratchet and spring urged pawl arrangement for retaining the lift members in their vertically raised position; and

2,752,205 Patented June 26, 1956 Figure 6 is a detailed perspective view showing the details of construction of the raising and lowering means for the upper sprocket gears for adjusting the tension of the sprocket chain.

Referring now to the drawings, the numeral 10 generally designates the sheet rock lift of the present invention. The sheet rock lift 10 includes four vertical members 12 having inwardly facing channel ways or guides 14 forming guides for slidable lift members 16 and 18. The upper end of the lift members 16 and 18 are interconnected by a pair of spaced longitudinal article supporting members 20 and transverse article supporting members 22 which project beyond the confines of the members 12 for forming a support area larger than the area defined by the members 12 for a piece of sheet rock when it is lifted towards a ceiling or overhead. The lift members 16 and 18 also include vertically spaced transverse members 24 on the inner side thereof for sliding engagement with the guides 14 wherein the lift or vertical members 16 and 18 engage the inner side edge of the vertical members 12. The lower ends of the vertical members 12 are secured in rigidly spaced relation by longitudinal and transverse members 26 and 28. Crossed braces 39 are disposed on the end and crossed braces 32 are disposed on the side for spacing the members 26 and 28 respectively. The lower corners of the sheet rock lift 10 are each provided with casters 34 for supporting the sheet rock lift 10 on a supporting surface for easy movement thereon wherein the sheet rock positioned on the supporting area defined by the members 20 and 22 may be vertically adjusted and moved into a desired position.

Adjacent the lower end of each of the lift members 16 and 18 is secured a lug 36 for attachment to a sprocket chain 38 wherein the lug 36 is positioned centrally of the lower most transverse member 24. Positioned transversely between the braces 32 adjacent each lower end thereof is a rotatable shaft 40 having a sprocket gear 42 thereon for receiving the sprocket chain 38. Secured adjacent the upper end of each of the vertical members 12 is a rotatable shaft 44 having a sprocket gear 46 thereon for receiving the sprocket chain 38 and the shaft 44 is rotatably journaled in oppositely disposed sliding bearing blocks 48. The bearing blocks 48 are slidable in a generally U-shaped bracket 50 secured to the respective vertical member 12 by suitable fastening means 52 and having one end bent at right angles substantially parallel to the bight of the bracket as indicated by the numeral 54 for attachment to the vertical member 12. Spaced vertically above the bracket 50 is a right angle bracket 56 having one leg thereof extending parallel to the U-shaped bracket 50 and secured to the legs of the vertical member 12 by fastening bolt 58. The elongated leg of the bracket 56 is provided with a cut out and right angularly bent portion 60 disposed horizontally and having a threaded aperture therein for receiving a threaded rod 62. The threaded rod 62 is provided with an actuating handle 64 on its lower end for engaging the under surface of the bearing block 48. The threaded rod 62 is threaded into the'portion 60 of the bracket 56 and passes through a suitable aperture in the bearing block 48 wherein the bearing block 48 may be raised and lowered by manipulating the handle 64 on the shaft 62 thereby varying the tension in the sprocket chain 38.

Positioned centrally between the upper longitudinal members 26 is a pair of rotatable shafts 66 positioned on each side of the center of the members 26 and the shafts 66 are journaled in the members 26 and support a central sprocket gear 68 thereon for engaging the sprocket chain 38. Positioned laterally from the shafts 66 towards the outer edges of the sheet rock lift 10 is a pair of rotatable shafts 70 having sprocket gears 72 thereon and the shafts 70 are rotatably journaled in the upper members 26 so that the sprocket chain encircles under the gears 68 and over the gears 72 thereby forming an idler sprocket gear for guiding the longitudinal movement of the sprocket chain 38. It will be seen that two series of gears and sprocket chains are provided in order to lift the lift members 16 and 18 to a desired vertical height.

In order to assure that the lift members 16 and 18 will operate simultaneously, spur gears 74 are provided on the outer end of the shafts 66 and the spur gears 7d are in meshing engagement thereby timing the vertical movement of the lift members 16 and 18.

In order to drive the shaft 66, a transverse shaft 76 is disposed between bearing blocks 77 on the upper edge of members 26 and provided with a handle 78 on its outer end and a spur gear 89 arjacent its inner end in meshing engagement with one of the gears 74 thereby driving the shafts 66 in unison.

In order to retain the lift members 16 and 18 in vertically raised position, a rachet gear 82 is provided on the end of one of the shafts 66 and the rachet gear has a plurality of teeth 84 for engagement by a spring urged pawl 86. The pawl 86 is mounted on a suitable shaft 88 on one of the members 26 and includes a tension spring 99 for urging the pawl 86 into engagement with the rachet teeth 88. An upstanding projection 92 is provided on the pawl 86 for providing a handle for rais ing the pawl 86 out of engagement with the rachet teeth 84 thereby permitting the lift members 16 and 18 to be lowered.

In operation, the sheet rock lift is used for raising large pieces of sheet rock to an overhead position as may be required in building construction. In order to accomplish this, the sheet rock is positioned on the members 2t) and 22 and the handle 78 is rotated thereby rotating gear 80 which is in meshing engagement with the timing gears 74 thereby rotating the sprocket gears 68 in timed relation for moving the sprocket chain 38 a predetermined amount. Inasmuch as the sprocket chains 38 are attached to the lift members 16 and 18 through the lug 36, the lift members 16 and 18 will raise or lower in unison. The tension in the sprocket chain 38 may be adjusted by turning the handle 64 on the threaded rod 62 in an obvious manner. Further, the gears 72 provide idlers for the sprocket chain 38 thereby assuring the easy operation of the device. After the lift members 16 and 18 have been raised to a desired position, it will be seen that the pawl 86 will engage the rachet S2 for retaining the device in raised position until such time as it is desired to lower the sheet rock lift 10.

*rom the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur 4 to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. A sheet rock lift comprising a pair of vertically disposed frame members, brace means interconnecting said frames in longitudinally spaced relation, each of said claims including inwardly opening channel members forming vertical guides, a pair of vertically movable article supporting frames slidably supported in said guides, each of said movable frames including a plurality of projecting members slidably received in said channel members, means for simultaneously raising and lowering the movable frames, said raising and lowering means including a pair of vertically spaced gears mounted adjacent each of the vertically disposed frames, a pair of parallel shafts mounted transversely of said brace means between the frames, said shafts being geared together for simultaneous rotation, handle means operatively associated with one of said shafts for rotation thereof, a centrally mounted gear on each shaft in alignment with the vertically spaced gears, an endless chain positioned over a central gear on a shaft and a pair of the vertically spaced gears, and means for attaching the chains adjacent the bottom of the respective movable frames whereby said movable frames are simultaneously movable upon rotation of the handle.

2. The structure as defined in claim 1 wherein each of said movable frames is provided with a cross piece at its upper end, said cross piece projecting beyond the confines of the frames, and a pair of detachable longitudinal members connecting the ends of the cross pieces and extending beyond the confines of the frames thereby providing a large area of support for engaging a sheet rock wallboard.

3. The structure as defined in claim 1 wherein the upper of each pair of vertically spaced gears is adjustably mounted for varying the tension on said sprocket chain, said handle means including a shaft mounted in parallel relation to the parallel shafts, a gear on said shaft in meshing engagement with a gear on one of the parallel shafts, and a handle on said shaft for rotating said parallel shafts for raising and lowering the article supporting frames.

References Cited in the file of this patent UNITED STATES PATENTS 1,629 Piper June 10, 1840 60,085 Tanner Nov. 27, 1866 1,718,503 Van Patten June 25, 1929 1,884,577 Comper Oct. 25, 1932 2,456,434 Manthie Dec. 14, 1948 2,586,227 Henderson Feb. 19, 1952 v

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