US1833484A - Hoisting device - Google Patents

Description

Nov. 24, 1931. H. s. GEER 1,833,484

HOISTI'NG DEVICE Filed Sept. 26, 1930 3 Sheets-sheet 1 INVENTOR 5w ATTORN Y NOV. 24, 1931. 3 GEER 1,833,484

HOISTING DEVICE Filed Sept. 26, 1930 3 Sheets-Sheet 2 INVENTOR f/aari 6662'- M ATTORNEY H. S. GEER HOISTING DEVICE Nov. 24,- 1931.

2 1 3 Sheets-Sheet 3 Filed Sept.

m T N E V m ORNEY Patented Nov. 24, 1931 UNITED STATES PATENT OFFICE HOBART S. GEER, OF CORONA, NEW YORK, ASSIGNOR TO AMERICAN SAFETY DEVICE CO., 015 NEW YORK, N. Y., A CORPORATION OF NEW YORK norsrme DEVICE Application filed September 26, 1930. Serial No. 484,507.

This invention relates to hoisting devices, and more particularly to scaffold hoists such as are generally used for raising and lowering scaffolds in the course of erection of a building.

It is the primary object and purpose of the present invention to provide such a hoisting device which is provided with reliable and positively operating safety guard means which will effectively prevent the descent of the scaffold, and possible serious accident re sulting in injury or death, in the event that the workmen should lose control of thehoisting device during operation thereof.

It is one of the important features of my present improvements to provide worm gearing for the operation of the rope or cable drum during unwinding of the cable therefrom for the lowering of the scaffold and I means connected with the operating handle for the worm gearing and normally locking said gearing and the drum against such rotation, while permitting of the rotation of the drum in the opposite direction to wind the rope or cable thereon.

. It is a further object of the invention to provide upon one end of the drum spring pressed pivoted pawls cooperating with a ratchet connected with the worm gear whereby said drum and gear will rotate as a unit in an anti-clockwise direction to lower the scaffold, and holding devices detachably engage able with said pawls to hold the same out of contact with the ratchetto permit of free rotation of the drum in the unreeling of the cable therefrom preparatory to rigging.

It is also another object of the invention to provide an operating lever for rotating the drum in a clockwise direction to wind the cable thereon having a pawl cooperating with a ratchet on theother end of the drum and means for releasably locking. said pawl upon the lever in a disengaged position for unreeling thee-able from the drum. There is also provided an additional safety pawl mounted on the machine frame and cooperating with said ratchet. I

It is a further general object of the invention toprovide a hoisting device of this character having the above noted improvements,

i an

characters designate corresponding parts which is relatively simple in its construction, light in weight and may be readily operated with a minimum of manual labor.

With the above and other objects in view, the invention consists in the improved hoisting device, and in the form, construction and relative arrangement of the several parts as will be hereinafter more fully described, illustrated in the accompanying drawings, and subsequently incorporated in the subjoined claims.

In the drawings, wherein I have disclosed one simple and practical embodiment of my invention, and in which similar reference throughout the several views,

Figure l'is an end elevation of a hoisting machine embodying my present improvements;

Fig. 2 is a side elevation thereof;

Fig. 3 is a detail view showing the locking clutch for the worm gearing in its released position;

7 Fig. 4; is an elevation similar to Fig. 1 of the opposite end of the machine;

Fig. 5 is an enlarged vertical sectional view through the drum and worm gearing taken substantially on the line 5-5 of Fig. 6;

Fig. 6 is a section taken on the line 66 ofFig. 5, and

7 is a detail perspective view of one of the pawl holding clips.

Referring in detail to the drawings, 5 designates two spaced vertically disposed end frame bars connected adjacent their upper and lower ends by the tie rods 6 and 7 respectively. Below the rod 7, the frame bars are divergently extended inwardly towards each otherand have their extremities extended downwardly in parallel relation between which the upper ends of a scaffold supporting stirrup frame generally indicated at 8 are rigidly fixed.

The drum 9 is rotatably supported between the frame bars 5 upon the shaft 10, one end or head of this drum being in the form of a ratchet 11. Between said ratchet and the adjacent frame bar 5, the end of a lever 12 is loosely mounted on the shaft 10 registering relation with a similar aperture 18 in the lever 12 when the pawl '13 is moved against the action offspring 1 1 out of contact with the teeth of 'the ratchet These registering apertures are adapted to receive a movable pin 19 which maybe-conveniently attached to the lever 12 by means of a short length of'-c'hain"20r When un reeling the rope; or cable indicated; at- R 'efrom'the d 'mn' re arator to of the "scaffold, the pawl 13 'may'thusbe ,l'oclred upon the lever-in an inoperative posit on.

The safety 'pa'wlshown at 21 hich is-"held' in engagement with the teeth of ratchet 11 by the spring 22 must of course, also "be disenga ed from'said ratchet, as well as the pawls which are associated with the worm gearing to be hereinafter referred to. In

order that the awl 21 be easily held in its-released positioml form the same 'witli'an upwardly obliquely projecting hand piece shown 'at-23 which may be easilyengaged'by the finger's'of theoperator grasping the frame bar 5 and pressed inwardly towards said frame bar.

, Above the pawl 21, a guide sheave 24: for the rope or cable R is suitably mounted up on the upper tie rod 6. p V f Between the opposite end or head '25. the drum 9 and the other vertical bar 5 of the frame, the worm gear 26 is loosely mounted on the shaft 10. A ratchet '27'may be integrally or otherwise connected with the gear 126 =.-and is disposed closely adjacent to the drum head uponwhich, at diametrically opposite sidesofsaid'ratchet, the pawls 28 are pivotally mounted 'to coact with the teeth of the ratchetandthereby connect the worm gear with the drum for rotation 'as a unit-in an anti-clockwise direction to permitunreeling of the rope or cable 'B'Of the drum; The pawls-28 are; held in engagement/with the ratchet27by suitableleaf springs 29 attached atone 'of their ends to the flanged edges of the metalrs'trips 30 secured to the faceof the drum head 25.' i V.

iBelowvthe worm gear 26, a horizontally disposed "ll-shaped bracket member 31 is suitably fixed to the machine frame, andin the spaced arms of this bracket member, the opposite ends of the wor1n32 arejournalled, said "worm being engaged with the lower side oft-he worm gear 26. Theouter face of-one of the armsof the bracket 31 is formed with a boss iha-ving clutch teeth 33 with which a slidingwclutch member 34 on the extended end, of the worm shaft is normally held in engagement by mcansof the coil spring 36 surrounding said shaft between said clutch member and the end of an operating handle 37 pivoted to the end ofithe shaft as at 38.

One end of a link 39 is pivotally connected with the clutch member 34 and has its other end pivoted to the operating handle 37 below the pivot 38 as indicated at 4L0, Thus, it will be understood that normally the handle 37 isheld in the angular relation with respect ings, while theolutch meniber 34 being en gaged with the clutch teeth 33'0f the fixed bracket thereby locks the worm 32 against rotation, preventing an anti-clockwise rotation dfthe'gear 'a'can-d the drum 9 and the unreeline: of the rope or'cable fromthelatter, hen it is desired to unreel the cable, preparatory'torigging, thelocking pawls 28 are held out ofengagement with the ratchet teeth 27 by means oftlie'metal clips 41 shown in Figs. 6. and r7 ofthe-drawingsc After the pawl-s are pressed away from the ratchet 28 against the actionof springs 29,-.one ofIthe an gularends o'f .the clips. areengaged against the inner edgesofthe .pawls wliile theother angular ends of 'saidfclipsare'engaged over the flanges-of the metal strips 30. "Thus,

after securingpawl 13, in its released position by meansof'. the pinvl9 on lever 12. and disengaging the: saftyipawl-i21 from, the ratchet 7 11, the rope or cable may be freely unwound from the drum. 1 c j I Having above fullydescribed the several mechanical parts ofthe-hoisting machine, its

operation willlbe understood as follows:

In rota-ting'the drum in a clockwise direction with reference to Fig. 1 of the drawings to. windfthe cablethereon, the lever 12 is vertically manipulated, and in each down stroke of saidleven'thepawl 13 engaging one of the teeth of the ratchet 11, rotates said 7 dr m to wind the cable thereon, the pawls 28cat the opposite end of the drum moving idly over'the teeth of the worm gear 26,'Which together with the orm'se are locked against rotation byfthe clutch'1neans 33, 34; In the event of breakage of [any of the parts at the latter end of the drum, failureto release the pawls 28, or the accidental disengagement of the clutch member 34from the teeth 33,-the descent of the. scafi'old'would be limited by contact of theleverv12 in its upward swinging movement withthe upperend of the machine frame,-if the safety pawl21 should also be broken or accidentally released.

Thus, it

will be seen that my present improvements j the frame, in the event of failure ofiboth'of the first named safety devices, will',}t revent thedescentof the scaffold,

i the scaffold is tofbe ,lQwered, :,tl1e

, withrespect to ratchet 11, he grasps the crank arm of handle 37 and pulls the same laterally to the position seen in Fig. 3 of the drawings, thus moving clutch member 34 against the action of spring 36 out of engagement with the clutch teeth 33. The scallold will then start to descend, the worm 52 being rotated through the connection of the locking pawls 28 on the drum and the ratchet 27 carried by worm gear 26. The operator of course, retains a firm grasp upon the crank handle 37, and controls the rapidity of descent of the scaffold. Should the operating handle 37 for any reason he released while lowering the scaffold, the spring 36 will immediately act to again engage clutch member 34 with the teeth 33, and thus check the further descent of the scaf old. leretofore, contact of the worm operating handle with the end head the drum has been relied upon to check the descent of the scaflold, but it has sometimes happened that either the handle or the end plate of the drum under the force of the im aact would break or the handle end would be displaced to such an extent that it would pass outside of the drum head. Several serious accidents have been due to this failure. By means of my positive clutch lock for the worm gearing as above described, any possibility of the continued rotation of the worm shaft after the operating handle has been released, is preeluded.

It will be apparent from the foregoing that the numerous safety features of my improved scafl'olding hoistswill be very effective in reducing the possibility of acci dents resulting in death or injury to the workmen to a minimum. \Vhile the various parts are of ruggeo and durable construction, the machine as a whole is comparatively light in weight and may be easily handled in the rigging of the scaffold, and operated with comparatively little manual exertion.

Also, it will be appreciated that my present improvements do not greatly complicate such devices as heretofore made and used, so that manufacturing costs thereof will not be materially increased.

While I have herein shown and lescribed a simple and practical embodiment of the invention which has given very satisfactory results in actual use, it is nevertheless to be understood that the essential features thereof might also be embodied in various other alternative structural forms. and I accordingly reserve the privilege of resorting to all such legitimate changes therein as may be fairly embodied within the spirit and scope of the invention as claimed.

tation includ n I claim:

1. In a hoisting machine, a frame, a cable drum revolubly mounted in the frame, means for operating the drum in one direction to wind the cable thereon, and means for controlling rotation of the drum in reverse direction to permit unrceling of the cable, said means including a loosely mounted gear, pawl and ratchet means connecting said gear with the drum for unitary rotation therewith in the latter direction, a drive gear in constant mesh with the first named gear, means connected with the drive gear to manually actuate the latter, and means for positively locking the drive gear against rotation including a part operatively connected to said actuating means and movable thereby to its released position.

2. In a hoisting machine, a frame, a cable drum revolubly mounted in the frame, means for operating the drum in one direction to wind the cable thereon, and means for controlling rotation of the drum in reverse diwith the drum for unitary rotation there with in the latter direction, a drive gear in constant mesh with the first named gear, an operating handle for the drive gear pivotally connected therewith, and clutch means for positively locking said drive gear against rotation including a spring pressed clutch member and connecting means between the same and said operating handle whereby said clutch member is movable to 21 released position by an initial. pivotal movement of said handle.

3. In a hoisting machine, a frame, a cable drum revolubly mounted in the frame, means for operating the drum in one direction to wind the cable thereon, and means for controlling rotation of the drum in reverse direction to permit unreeling of the cable, said means including a loosely mounted gear, pawl and ratchet means connecting said gear with the drum for unitary rotation therewith in the latter direction, a drive gear in constant mesh with the first named gear, an operating handle for the drive gear pivotally connected therewith, and clutch means for positively locking said drive gear against r0- m a spring pressed clutch member, and'a linl: pivotally connected to said clutch member and to said operating handle to wind the cable thereon, means for releasably locking said pawl upon the lever in an "inoperative "position, means mounted at the opposite endof thedrum for rotatingthe same in a reverse direction to unreel the cable therefrom, said means including an'operating handle, and means automatically effective upon'the release of said handle to posltlvely lock said last named means against rotation. In aho1st1ng machine, a frame, a cable' drum revolubly mounted in the frame and having a r'atchethead atone end thereof, a

vertically swinging lever, a spring pr essed "pawl carried by the lever cooperating with the ratchet to rotate the drum in a direction to wind the cable thereon, a member carried by'said lever releasably engageable with a part ofthe pawl and with said lever to lock the pawl in an inoperative position, means mounted at the opposite end ofthe drum for rotating the same 1n a reverse dlrec-tlon to unr'e'el the cable therefrom, said means including an operating handle, and means automatically effective upon the release of said handle to positivelv lock said last named means against rotation. r

6. In a hoisting 'machine, a frame, a cable drum revolubly mounted in "the frame and having a ratchet head at one end thereof, a vertically swinging lever, a spring pressed pawl carried by the lever cooperating with to wind the cable thereon, means for releasably'lockingsaid pawl upon the lever in an inoperative position, "a safety pawl pivoted on theframe spring pressed into engagement with said ratchet head and having a hand piece obliquely projecting upwardly from its pivoted end for movement of said pawl to a disengaged position, means mounted at the opposite end of the "drum for rotating the same in'a reverse direction to'unr'eel the cable therefrom, said means including an operatmg handle, and means automatlcally effective upon the release of said handle to positively look said last named means against rotation.

7. Ina scaffolding machine, a frame, a cable drum revolubly mounted therein, manuallyoperable means for rotating the drum in onedirection to wind the cable thereon, and means for rotating the drum in the opposite direction to permit unwinding. of the cable, said means lncludlng a looselymountnsasgaaa pawls and with parts fixed to the drum to hold said pawls out of engagement with the ratchet and permit'ofr'otation of the drum to unreel the cable independently j of said m gearln-g.

In testimony that I claim the foregoing as my invention, have signed my name hereto.

HOBAR s. GEER.

theratchet to rotate the drum ina direction means between the clutch member and the crankliandleto move said clutch member to released. position upon an initial pivotal movement of the crank handle, and members adapted to be detachably engaged with said

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