US1238466A - Electric hoist. - Google Patents

Description

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f ELECTRIC HOIST BEST VLBLE COPRPPLICATION man ocT. 22. 1912.

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ELECIRIC HOIST. APPLICATION FILED oc. 22. 1912.

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.ARCHIBALD Si* WATSON, OF DETROIT, MICHIGAN, .ASSIGNOR TO DETROIT HIST AND MACHINE COMPANY, F DE'lllOIT, MICHIGAN, A CORPORATION OF MICHIGAN.

ELECTRIC HOIST.

dt- Specification of Letters Patent.

To au w/'wm t guay Concern.'

Be it known that I, ARCHIBALD S. WAT- sides in the novel construction of a magnetic brake; in the peculiar arrangement and comy struction of the mechanical clutchand brake', and in certain details of construction, as will more fully hereinafter appear.

Figure 1 is a iront elevation of the device enihodyingmy invention, partly in section;

Fig. 2 is an end elevation o f a portion of a frame; and

Figs. 3 and t illustrate certain rdetails of arrangement. z

l designates the frame of the hoistY and 2 the motor mounted thereon. 3 is a driving shaft 'forming an extension of the motor shaftand 4 designates the shaftof the winchv ing drum 5 in the forinof a hollow member i sleeved upon the shat't 3 and suitably journaled in `bearings G and 7 in the frame. The

shaft 3 has the outer end thereof journaled in a bearing 8 and is :tree to rotate,1ndel pendent oit' the sleeve Il.' The outer ehd of the member projects beyond. the bearing and is iiriedly secured to one of the coperating members as 9 of a cone clutch.` The other co'c'iperating member 10 is secured to vthe easing; against rotation as by means of lugs 11, but is free 'toy slide longitudinally. 12 is a magnet controlling movement of the member in the usual manner. l

In order that the" magnet may bel readily accessible for repair, I arrange the magnet easing' jllerteriorly" of the end lll of thetrane, and preferably the end 14 is pr vided with a recessed portion Within Whici the arumture easing is detachahly securedl by menus olE screws l5. The armature 1G of the niaggnet also is arranged exteriorly of the casing end andA within the 4recessed. portion, tho- :xrniature being; :ittacl'ufd to the brake member l() hy means of :i sha'it or stud 17 which 'is slidably mounted in a 'hearing' 18. 'is usual inthis type et broke theI arma re is; uori'uullj; held away from the mag- :wtiliv :uvam: ol' e Spring; :LH if), which tends ratentednug. 2s, 1917.'

.Application filed October 22, 1912. Serial No. 727,11*

Vto retain the coperating portions of the brake in the desired frietional engagemen lt frequently becomes necessary to adj, tA the tension of the spring-seas to takeifup wear between the cone members, or to readjust the latter to different kinds of work. I have, therefor'e,positioned the spring 19 iny aentral bore 2O in the magnet and provided an adjustable abutment. for the 'outer end of the spring in the formof afscrew 21 having a threaded engagement witllgipthe bore 2() and accessi-ble through the outer end of the bore, which is open. The other end of the spring .i9 vengages a pin 22 that has a sliding engagement with the inner end of the i'i'iagnct'bore, This pin has a bearing on the inner face of the armature Lbut is not attached to the latter, since by forming the pin free from the armature it is not necessary to accurately, aline lhc bore with the bearing 18 of the shalt 17. It vwill be read` ily appreciated that if the magnet were ar' ranged within the frame, and the pin 22 Was fixed t'o the armature a very accurate alining of the hearings 17 and here QOwould be required, in order to avoid binding of the parts. j

The -v drum 5 is driven from the shaft through a step-down drive train. As shown, 23 is a counter-shaft vjourualed .in suitable bearings 24- 24", inf the frame or casing' l, and 25 isa sleeve surrounding the co'un'tershaft andvl'ree to rotate in relation tliereto.

IThis sleeve is driven fromY the' shaft 3 by' means of a gear 26 and-pinion -27 fixed respeetively to the sleeve and the shaft. The eoljintcr-shaft is rotated fronitheltsleeve 25 through the medium of a combined clutch and brake' mechanism tol-ie hereinafter deine a gear 32.- lhe latter member is lixedl l100 secured to a pinion 33 that drives a gear 34. attached to the slm'lt l of the drum. Both the gear r'luud pinion 38 are loosely mounted on a stud shaft Q3 arranged in a l'iearing' nef-esmwily oecur il the men'ilmr itil was :in extension oll (he shalt sha-Pt is a pinion 28 meshing". with a gear."V

'23" in the casing. v'lhis stud sha/'ft isfprefer- 1 05# mdepemleut thereof und stationary so as f 'l`hus, upon rota- 110 tion of the shaft 3 the pinion 27 drives the gear 26, which rotates the sleeve 25, driving through the medium of the combined clutch and brake 'mechanism the shaft 23. f Upon rotation of the latter the member-28 rotates the drum shaft 4 through the intermediate gears 29, 31, 32' and 33 and the gear 34.

The combined clutch and brake connection between the sleeve 25 and shaft 23 is preferably of the friction disk type and coniprises coperating members or heads 35 and 36 both splined to the shaft 23, and intermediate friction disks 37 and 38. The disks 37 also are splined to the shaft 23 and the disks 38 are provided with peripheral bearings 39 engaging pins 40 projecting laterally from a member 41 which has a hub 42 loosely mounted upon the hub 43 of the head 36. Surrounding the hub 42 is a brake memtional contact with the hub 42 and lock the latter against movement.

Upon forward rotation of the shaft 3 the frictional disks are clamped together by means of coperating cam f aces 47 and 48 on the adjacent ends of the sleeve 25 and the head 35. These cam faces comprise oppositcly arranged spiral inclines forming shoulders 49 and 50 which in the released position abut or are in immediate proximity to each other. However, when the sleeve 25 is driven in the direction to hoist the cam 47 is moved relative to the cam 48 in a direc tion to cause the cam faces to separate the sleeve 25 and the head 35, thereby forcing the latter inward and clamping the frictional disks. i

In operation, assuming that the motor is to be driven in the forward direction, or in the direction to hoist, upon turning on the current the magnet 12 will be polarized, attracting the armature and withdrawing the brake member. The releasing of the brake will permit the shaft 3 to be rotated in the direction indicated by the'l arrow c, which will drive the sleeve 25 in the opposite direction and cause a relative movement of the incline faces in a direction to force the head inward and clamp the disks. This relative movement of the cam faces is effected since the load tends to resist rotation of the shaft 23. 'lliei-(ifore, the greater the load the greater the clamping action upon the disks. ln other words. the clamping of the clutch parts is proportional to the load.

'lhe clamping ol' the disks rotatively sccures the member 41 to the heads 35 and 36 and as the roller brake permits free rotation of the hu'b 43 during hoisting, the friction disks and the heads form a clutch for coupling the sleeve 25 to the shaft 23.

During lowering of the load the friction device acts as a brake and the brakingaction also is proportional to the load. Thus, when the load@y is to be lowered the motor is reversed, driving the shaft 3 in the direction opposite from that indicated by the arrow a and likewise reversing the remaining parts of the drive mechanism. The sleeve 25 then rotates as indicated by the arrow b which tends to move the incline faces 47 and 48 to 80 their normal position, or inthe position to I release the friction disks. The load however tends to cause the shaft 23 to run ahead fof the sleeve 25 so to speak, and the heavier the load the greater will be this tendency. Since the member 35 is splined lto the shaft 23 the action of the load will be transmitted fore, during lowering of the load .are held 95 isks 37 rotate, producstationary while the ing a braking action that is dependent upon the pressure applied to the head 35, which pressure, as before stated, is roportional to the load. In case there is no oad applied to 100 the hoisting hook during lowering, the cam 48 would be turned until the shoulders 49 and 50 abut, which would positively rotate the shaft 23 through the splincd connection between the latter and the member 35.

The combined clutch and brake serves an additional `function, namely,-,to prevent the load running away in case the cone brake did not operate properly. Thus, if upon turning off of the current the friction enga ement of the parts ,9 and 10 was not su cient to stop the mechanism any tendency of the load to run ahead of would result in the forcing of the member 35 inward, which as before. described, would cause the friction disks to act as a brake.

In order to condense the structure and at a head 54 that closes a hollow cylindrical 13o the sleeve 25 :necesites projection 55 forming a housing for the roller clutch. Ready access to the clutch parts is had by 'forming the head 54 detachable.

What I claim as my invention is:

'In an electric hoist, the combination with a drive and driven member, of a driving connection between said members includ* ing coperating relatively movable clutch heads secured to one of said members, said heads rhaving hubs, coperating friction disks `interposed between said heads, a portion of which are attached to the last-men tioned member, a member loosely mounted on one of said hubs and provided with a laterally projecting pin to whichlthe remaining' portionof the disks are connected, a connection betweenthe casing and vthe last .mentioned member permitting movement of the latter in 'one direction and Withholding the same against rotation in the opposite direction, the other of said hubs and the other of said drive and driven members loeing provided with engaging oppositely disposed inclined bearing faces. In testimony vwhereof l ailx my signature in presence of two witnesses.

ARCHIBALD S. WATSON. 'Witnesses WM. Jj Barnim?, JAMES l). BARRY.

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