US2279853A - Portable hoist - Google Patents

Description

April 14, 1942. F. L. WHITE 2,279,853

PORTABLE HOIST Filed June 1'7, 1940 3 Sheets-Sheet l April 14, 1942. v ITE 2,279,853

- PORTABLE HOIST Filed June 17, 1940 3 Sheets-sheet 2 V 28 3 20 V r. r 24 F. L. WHITE PORTABLE HOIST -3 Sheets-Sheet 3 Filed June 17, 1940 Patented Apr. 14, 1942 UNETED STATES PATENT OFFICE Fred L. Whiti h l r i jlf ofii i aisignor to The Osgood Company, of Ohio Marion, Ohio, a corporation Application June l7, 1940, Serial No. 340,881

7 Claims.

This invention relates to portable material handling devices and is more particularly directed to a device for positively drawing the cable from the winding reel or drum bytaking up the slack as the cable is being unwound.

The object of this invention is to provide a mechanism in a material handling. device adapted to positively withdraw the cable as it is unwound from the winding reel or drum andpass it over the boom sheave.

Another object of this invention is to prevent an unwound cable from piling near the winding drum or reel on the platform and boom of a portable hoist and thereby requiring excessively hard labor to withdraw it over the boom sheave.

Another object of the invention is to prevent the snagging and kinking of the hoist cable on the boom of the hoist.

A still further object of the invention is to provide a throwout device or slack puller on the boom of a portable hoist to positively draw unwound hoist cable away from the reel or winding drum and out over the boom sheave.

Another and still further object of the invention is to provide a means on a material handling device which operates in synchronism with the cable reel or drum to maintain a taut condition in the hoist cable between said means and the reel.

Other and further objects of the invention will appear to those skilled in the art to which this invention pertains as the description proceeds which taken in connection with .the accompanying drawings sets forth the preferred embodiments of the invention but it is. distinctly-under: stood that such description and disclosureis not to be taken as a limitation of the invention which ployed very frequently employ tools on the free end of. the cable that passes over the sheave on the free. end of the boom that are insufiicient in Weight to positively pay out. the cable over the boom sheave. It has been necessary in the past to require .helpers to. draw the cable over the boom sheave as it is being paid out from the reel "or drum. If this is not done the cable will pile upon the boom or cabin deck or platform of the hoist causing it to kink and become snagged as it is unwound from the drum. Applicant has therefore provided a throwout device or slack pullerwhich is mounted on the. boom, preferably near the sheave to positively pass the cable from said drum as it unwinds out over. the boom sheave thereby obviating the necessity .of a helper. pulling the cable over the boom sheave as it unwinds and preventing the snagging and kinking previously described.

A preferred embodiment of the aforementioned device is more particularly set forth in Figures 1 is limited only by the appended claims and any 1 and all variations, modifications and alterations of structure coming within the spirit and scope thereof are included herein.

In the drawings: Fig. 1 shows a schematic side elevational view of a portion of a portable hoisting device.

Fig. 2 shows a plan view of the boom shown in Fig; 1. Fig. 3 shows a side elevational view of the boom showing the driving means mounted thereon.

Fig. 4 is a sectional view of the piston'and cylinder device used in Fig. 3.

Fig. 5 shows a side elevational View of a modification of the invention. i

Fig. 6 shows a plan view of a section of the boom indicated by the arrowedlinesof 'Fig. 5.

Portable crane type hoisting mechanism, drag-' lines and similar devices in which a cable is emto 4 inclusive, in which JIJindicates the operators deckor platform of a portable crane hoist and on .which" deck' the operating mechanism for drawing in or unwinding the hoist cable is mounted- A boom 2 is tiltably mounted on the platform I on a pivot 3 and maybe .tilted. by a conventional means (not shown). At the opposite end of boom 2 a sheave 4 is rotatably mounted in appropriate bearings supplied therefore and each of which. constructions is also well knownto the art. The hoist has a winding reel or drumJS which isrotatably mounted on the deck or plat;- form I in any Well known manner. Motive power for the operation of the'drum is supplied from any well known prime mover which is connected toga gear 6 preferably mounted on the pin or pivot 3. Gear 6 is connected toan idler! whichin turn is connected to a gear or wheel 8 which rotates the winding reel or drum 5. Each of the foregoing is shown schematically to more clearly illustrate the operation. 1

A cable9 is wound on the reel 5, and is ledto' the sheave 4 on the end of boom 2 and has an appropriate tool Ill secured thereto.

r 3 Gear 6 has a sprocket ll integrally associated therewith. which is connected to a second sprocket [2 driving a gear 13 rotatably'mounted in housing I4. A sprocket chain I5 or other suitable power transmitting mechanism connects sprockets H and I2 to transmit rotary motion to drive gear l3. The gear-box or support l4 ismounted upon a platform It secured to boom 2. l Gear box 14 has a second gear ll, meshing with gear i3. rotatably mounted therein to which a shaft l8 is operatively connected. Shaft l8 extends to theslack puller or throwout device |9 which is suitably mounted on a base fixed to the boom 2. The shaft l8 has fixed thereto a gear 2| which engages a gear 22 secured to shaft 23 rotatably mounted in the slack puller or throwout device l9. Mounted upon the shaft 23 is a sheave 24 which is adapted ,to be engaged by the cable 9 by means of mechanism hereinafter set forth.

It is apparent therefore that the sheave 24 is constantly rotated. The gears driving sheave 24.. to the motor 50. The cable 31 is in constant and the cable or'reel or drum 5 are so arranged and proportioned such that there will alwaysbe a substantial amount of tension in that portion of the cable 9 extending between-the sheave'24 Attention is still fur and the drum or reel 5. ther invited to the fact that cable 9 is only in enengagement with sheave .49.

gagement with sheave 24 when the reel.5is' .pay-" ing out or unwinding cable 9.

Means have been provided to positively engage the cable .9 .with the sheave 24 which comprises .a sheave25ireely rotatably mounted on a lever'26 pivotally mounted tobase 2'0.of the throwout. de-.

vice 19. on pivot .21.. A fluid pressure motor 28 I mounted .on boom 2 has its pistonrod 29 connected to the free end of lever 26 Cylinder 30 is rigidlymountedon said boom 2 and piston 3|, to which pistonrod 29 is connected, moves relatively thereto whereby sheave 25 is vertically ade justed or moved relatively to the. shjeave.2 4. .A

conduit .32 is connected to the cylinder 30 for the purpose of transmitting pressure .fluid' thereto. Anappropriate valve 33 is mounted on the deck or platform I to manuallycontrol theadmission ofpressurefluid to the motor v.28. A suitable source of pressure ,fiuid, mounted on deck .I, is

provided in order to operate the motor 28. Mo-

tor28, as will be observed, is a single actingv motor. Attention is further invited vto the fact that sheave 25 is disposed immediately below and .in line with or in the same plane as the sheavei24 and is constantly engaged by the cable-9.

The'operation of this device provides for positively taking up thecable 9 as it is unwound from the reel or drum 5. When therefore the -un-= winding operation. is being performed the operatoractuatesmotoriil which urges the pivoted lever 26 upwardly thereby bringing-the cable 9 in engagement with the rotating sheave 24. The frictional engagement of the cable 9 and the sheave 24 is sufficient to cause any slack occur-- ring in cable 9 to be taken up thereby positively paying out the cable over the sheave 4 and preventing any possible kinking or snagging of the cable 9 near thedrum'5 on the deck or platform Persons manipulating and handling any instrumentalities adapted to beconnected to tool III are therefore relieved of the necessity of drag-. ging out the cable 9 and eliminating the troublesome kinks and snags that might otherwise occur. V

A modification of the aforementioned structure is set forth in Figures 5 and 6 in which the basic boom 34 and platform 35 are pivotally associated one with the other. A cable winding reel .or

drum 36, schematically illustrated, is operativelyassociated. therewith on which a cable .31 is wound andhaving an appropriate tool 38 :connected thereto. is led out over the sheave 39 .ro-

tatablyfmounted on the free end of the boom 34.

the platf orm 49 and upon which a sheave 43. isrotatablymounted in ;,a housing 44 on shaft 45','

sheave 25 prevou sly, described. A fluid pressure motor has a conduit 5| connected thereto which in turn is connected to an appropriate valve 52 to control the admission of pressure fluid Sheave 49 lies in the same plane assheave 43 and when pressure fluid motor .50 is operated the cable 31 is brought "into engagement with'the sheave'43. Motor 4| may be constantly rotating or it may be rotating onlyat such times as when the cable 3'! is being paid out but in either event the vertical movement of'the sheave 49 is necessary to bring the cable 31inv engagement with the sheave 43, -The operating relationship of sheave 49, cable 31 and sheave .43. is identical to that previously described in connection with Figures 1 to 4. The speed of sheave 43 is .proportioned to thespeed of drum 3.6 such that'cable 37 will be in tension; i. e.; the

.speedswill in effect be more or less synchronized.

. gear box l4 and slackv puller I9.

The. above isconsidered to so fully reveal the gist of the invention that anyone studying the principles of its operation and the construction described may reproduce the same. That which is considered new, novel and useful and which is sought to be protected by Letters Patent of the United States is asiollows:

1 claim:

-1. In a portable hoist; a platform; a cable reel'adapted for rotation and mountedon said platform; a boom mounted on said platform and having a sheave on its free end; a cable wound on 1said reel and extending over said boom sheave; a slack puller mounted on said boom adjacent theboom sheave, comprising a sheave, means to drive said sheave substantially synchronously with said reel which includes means extending longitudinally of said boom and driven from said reel, and also comprising a pivoted lever mounted on said boom and carrying an idler sheave, said cable passing over said idler; pressure fluid operated means connected to said pivoted lever to move the cable passing over said idler sheave into engagement with said slack puller sheave; and a valve means on said platform operatively connected to said pressure fluid operated means to remotely control said pressure fluidoperated'means. r

2. In a portable hoist; a platform having a reel rotatably mounted thereon and a cable thereon; a boom pivotally mounted on said 'platform, said boom having asheave on its free end overwhich said cable passes; a slack puller mounted on the boom substantially adjacent the boom sheave, said puller including a rotatably mounted sheave, means to rotate said sheave at a speed which is substantially that of the cable reel whichincludes means extending longitudinally'ofsaidboom and driven substantially synchronouslywith said reel, a pivoted lever on said slack puller rotatably supporting an idler sheave,

sheave to thereby take up the slack in the cable as it is unwound from said reel; and a controller to govern said last mentioned means mounted on said platform.

3. In a portable hoist; a platform supporting a winding reel; a boom pivoted to said platform and having a sheave rotatably mounted at one end thereof; a cable on said reel and passing over said sheave; means on said boom to take up slack in said cable as it is unwound and mounted substantially adjacent said boom sheave including, a sheave rotatably mounted on said means, electric motor means to drive said sheave at a speed substantially that of said reel, a pivoted lever rotatably supporting an idler sheave on said means to take up slack and over which said cable passes; pressure fluid means connected to said lever to vertically move said idler to bring said cable in contact with said rotatably mounted sheave, whereby any slack in said cable is taken up as it is unwound from said reel; and a valve mounted on said platform to govern the actuation of said pressure fluid means.

4. In a material handling device; an operating deck; a boom pivotally secured to said deck and having a sheave at its free end; a cable winding device; a cable on said device which passes over said sheave; a slack puller mounted on the boom substantially adjacent said boom sheave, which includes a driven sheave and a movable idler sheave, said cable passing over said idler sheave, and means to move said idler sheave toward said driven sheave to bring said cable in contact with said driven sheave; means to rotate said driven sheave including a shaft extending longitudinally of said boom; means to rotate said shaft, said means being mechanically linked to said cable winding device; said winding reel and said driven sheave being rotated at speeds such that the cable between said winding device and said sheave will be in tension; and a controller mounted on said deck for governing said means to move said idler sheave to selectively bring said cable in contact with said driven sheave.

5. In a device of the character described; a platform; a cable drum rotatably mounted on said platform; a boom tiltably mounted on said platform; a sheave rotatably mounted on the free end of said boom; a cable wound on said drum and passing oversaid sheave; means near the free end of said boom adapted to positively pass said cable over said sheave as it is unwound from said drum, said means including a driven sheave and an idling sheave mounted for movement relative of each other, said cable running over said idling sheave; means extending longitudinally of said boom and operatively connected to said drum to drive said driven sheave; means to relatively move said idling sheave and said driven sheave to bring said cable against said driven sheave; and a controller for said last mentioned means mounted on said platform to govern the relative movement of said idling and said driven sheaves.

6. In a portable crane device; a platform having a drum rotatably mounted thereon; a boom tiltably supported on said platform and having a sheave rotatably mounted on its free .end; a cable throwout device mounted adjacent the free end of said boom, including a driven sheave and an idler sheave mounted for movement towards and away from said driven sheave; means to drive said driven sheave from said drum and extending longitudinally of said boom; means to control the application of said throwout device to a cable extending from said drum to and over said boom sheave including a pressure fluid device to move said idler sheave toward said driven sheave, said cable passing over said idler sheave; and a valve for said pressure fluid device mounted on said platform to govern the admission of pressure fluid to said device and bring said cable into contact with said driven sheave.

7. In a crane device; a platform; a drum adapted for rotation and mounted on said platform; a boom tiltably mounted on said platform; a sheave on the free end of said boom; a cable wound on said drum and having one end led over said sheave; a cable throwout device, including a driven sheave and an idler sheave relatively movable, mounted adjacent said boom sheave, said cable passing over said idler sheave; means to drive said driven sheave comprising a shaft extending longitudinally of said boom; gear means connecting said drum to said shaft; gear means connecting said shaft and said driven sheave; a pressure fluid system to relatively move said idler sheave and said driven sheave to bring said cable into contact with said driven sheave; and a control means for said system including a valve mounted on said platform to govern the admission of pressure fluid to said system.

FRED L. WHITE.

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