F. Ev STAHL I-IOIS'I DRUM Dec. 18, 1934.
Filed Jan. 21, 1935 JIVVENTO/f' K E. 5 TAHL FRAN Patented Dec. 18, 1934 HOIST DRUM Frank E. Stahl, Tonawanda, N. Y., assignor to Columbus McKinnon Chain Company, Tonawanda, N. Y., a corporation of New York Application January 21, 1933, Serial No. 652,843
6 Claims.
My invention relates in general to improvements in hoist drums and more particularly to means for causing the second layer of cable to wind uniformly upon the first layer.
It is well known to those skilled in theart 5 that in winding a second layer of cable upon a hoist drum, there is a tendency for the cable or wire rope to overlap and pile upon the last coil of the first layer and/or against the flange of the drum. This may continue for two or three coils of the cable whereupon the additional coil or coils will slip off of the coil or coils underneath and move down to the level of and in contact with the first layer of cable with resultant jarring of the load which the cable has been lifting.
The principal object of my invention has been to overcome the disadvantages above pointed out and to provide means whereby the cable shall be started off on its second layer without an opportunity to pile.
Another object has been to gradually raise the last coil of rope about the drum in such manner that it may be carried up to the level of the second layer whereupon it will be positively forced over into the groove formed by the last two coils of the first layer.
Another object has been to provide a drum in which the point where reeving of the second layer of rope starts shall be definitely determined, making it possible to place two drums on a single shaft and to so set such drums as to effect synchronous reeving.
Another object has been to provide means for fastening the inner end of the cable to a relatively small drum so as to prevent breaking of the cable, thereby increasing its life.
Furthermore, the above objects have been brought about in a manner which does not add materially to the cost of an ordinary hoist drum.
The above objects and advantages have been accomplished by means of the device shown in the accompanying drawing, of which:
Fig. 1 is a front elevation of my complete drum, showing the cable coiled about it and in crosssection.
- Fig. 2 is an end sectional view taken online 2--2 of Fig. 1.
Fig. 3 is a similar section taken on line 33 of Fig. 1 and shows the fastening means for the inner end of the cable.
Fig. 4 is a fragmentary, transverse, sectional view taken on line 4-4 of Fig. 2.
5 is a similar view taken on line 55 of Fig. 6 is a similar view taken on line 6-6 of Fig. 7 is a similar view taken on line '7'1 of Fig. 2.
Fig. 8 is a fragmentary, transverse, sectional view of a drum provided with guiding means at the opposite end, whereby a third layer of cable may be properly reeved.
Fig. 9 is a side elevation showing my invention as applied to two drums carried on a single shaft.
Referring to the drawing, 10 represents my 10 hoist drum which is provided with a periphery having the customary helical groove 11 for the cable orwire rope 12. The bottom of this groove is, of course, concave so as to fit the size of wire rope orcable 12 being used. The starting end 13 of the groove 11 terminates in a curved wall 14 which forms the bottom wall of ahole 15 through which the fixedend 16 of thecable 12 passes into the interior of the drum. The curvature of the wall 14 meets and joins the curvature of the drum periphery in a very smooth gradual manner so that this end of the cable is not bent to such a degree that it will be kinked or weakened by such bend. The extreme inner end of the cable is passed into the interior of the drum where it is provided with ananchor 17 which is fitted over and secured to the end of the cable by well known means, whereby it will be securely fastened to the cable. When tension is placed upon the cable, the anchor will bear against the end face of the wall 14 which extends around thehole 15 and joins thebody 18 of the drum. The helical groove 11 extends across the periphery of the drum from the starting end 13 at a pitch equal to substantially the diameter of the cable orwire rope 12. This helical groove is concave as hereinbefore pointed out but starting at substantially the point 20 (see Fig. 2) in its last turn, the bottom of the groove is gradually filled in up to substantially the point 21 so as to bring the bottom of the groove up to the level of the top edge thereof. At the point 21, the surface is merged into and continues in aridge 22. As shown in Fig. 4 thelast coil 23 of the cable is in the last turn of the groove 11, but at a point which is slightly above the normal level of the previous turns. This view, therefore, shows the cable slightly raised, and in Fig. 5 this layer of the cable is raised still higher and is carried upon the upper surface of theridge 22. Theridge 22 is of increasing radius and thereby gradually raises the last coil of rope up to a point where it is substantially on a level with the top surface of the first layer of rope. This position is shown inclined toward the axis at the opposite end of the drum, such inclination increasing as the outer end of the ridge is reached, thus causing the last coil of the rope to slide over in close contact with the last previous coil.
The drum is, of course, provided withend flanges 25 and 26. Theflange 25 is at thestarting end of the drum, and theflange 26 is at the finishing end of the drum. Fig.1 shows the last coil of cable raised to a position Just preceding the position shown in .Fig. 6. Carried by the inner face of theflange 26 is a push-over cam 2'7. This cam is at its maximum lateral dimension at theapex 28 and gradually rises to this apex over aninclined surface 29 which starts atpoint 30 which is slightly back of the point where the sectional view of Fig. 6 is taken. Theapex 28 extends over and above the first layer of rope or cable and the cam at its maximum lateral dimension is undercut, as shown at 31 in Fig. 2, so as not to interfere with the winding of the last coil of the first layer of the wire rope. Theapex 28 of this cam extends over the first layer at apoint about over its center line. It will be obvious that as the rope extends from the drum, it will be gently pushed or urged over toward the groove formed between the first and second last coils of the first layer of the cable, thus insuringv its engagement with this groove when the first coil of the second layer is wound upon the drum.
Where the amount of cable handled is too great to be'woun'd upon the drum in two layers, the drum may be formed with aridge 35 and acam 36 at the starting end of the drum, as shown in Fig. 8. In this figure the drum flange 3'7 is so located with respect to the first turn of the groove 11 that a plane passing through the inner face of'theflange 37 is interspaced with thefirst coil 39 of the first layer so as to allow thelast coil 38 of the second layer to move beyond thefirst coil 39 of the first layer. Theridge 35 will be gradually increased in diameter so as to cause thelast coil 38 of the second layer on the drum to be raised up to the elevation of the third layer in a manner similar to that at the starting of the second layer, thecam 36 being so positioned as to cause this last coil of the second layer when it is elevated to be pushed over between the first and second last coils of the second layer in a manner similar to that described in connection with the winding of the first coil of the second layer.
From theforegoing'it will be obvious that as thecable 12 approaches the last convolution of the first layer in the groove 11, it is first gradually raised to the top of the periphery of the drum and then further gradually elevated by theridge 22 until it is substantially at the top of the previous coil of the first layer. As the drum continues to rotate, thecam 27 will come in contact with the cable as it is being reeved thereon and gently push it over into the groove formed by the two last coils of the first layer, thus positively guiding the first coil of the second layer and preventing the possibility of its piling on top of the last coil of the first layer or between the first coil of the second layer and the flange of the drum.
In cases where two or more drums are used on a single shaft, as shown in Fig. 9, my invention makes it possible to accurately set both drums so that the second layer of rope or cable on each drum will start at the same time it being well known that two drums have heretofore been used I 1,ee 4,eo4 in Fig. 6. The upper surface of the ridge 22- is for handling only single layers of cable. This can be done because the point in the rotation of each drum where the first coil of the second layer starts is accurately determined by the push-over cm 2''.-
such coil being brought upto such starting point by the filled-in portion of the end of the groove 11 and by theridge 22. This feature of my invention is of great value in a two-drum hoisting device, such as that shown in Fig. 9. ,In this figure thelines 40 indicate thelower inclined surface of a roof ofa box car or othersuitable supporting surface to which thebearing brackets 41 are attached. These brackets are, of course, permanently secured to the supporting surface and they carryashaftiz. Oneoftheendsofthisshaft protrudes a considerable distance beyond the end of one of the brackets and ahoist 43 is mounted thereupon. This hoist is preferably provided with an attaching ear 44 which is permanently secured in an adjustable manner to abracket 45, rigidly fixed to the supporting surface. This hoist is provided with theusual hand wheel 46 over which a handchain 47 (shown indot and dash lines) is passed. Carried by theshaft 42 and arranged preferably near each of thebearing brackets 41 is a cable drum 48. As shown by this figure, the drums are so placed upon the shaft that theapex 28 of each cam lies in substantially the same axial plane passing through the shaft, whereby when thecable 12 reaches the second layer, these pushover cams will cause the second layers on both cams to be started at the same instant.
- While I have shown my invention as applied to a drum having a helically formed groove, it is obvious that my invention is applicable also to drums having smooth peripheries. This and other modifications of the details herein shown and described may be made without departing from the spirit of my invention or the scope oi. the appended claims, and I do not, therefore, wish to be limited to the exact embodiment herein shown and described, the form shown being merely a preferred embodiment thereof.
Having thus described by invention, what I claim is:
1. As an article of manufacture, a hoisting drum having a rope receiving periphery, a relatively long circumferential lifting ridge formed at the finishing end of the drum, said ridge being formed with a gradually increasing radius for carrying the last convolution of the first layer of rope upon the drum up to substantially the top of such layer, and a relatively short push-over cam carried on the inner face of the end flange at the finishing end of the drum and located substantially where said ridge is at its maximum radius, said cam extending above the last convolution of the preceding layer to a point over substantially the. center of such convolution.
2. As an article of manufacture, a hoisting drum having a rope receiving periphery, a relatively long circumferential lifting ridge formed at the finishing end of the drum, said ridge being formed with a gradually increasing radius for carrying the last convolution of the first layer of rope upon the drum up to substantially the top of such layer, and a relatively short push-over cam carried on the inner face of the end flange at the finishing end of the drum and located substantially where said ridge is at its maximum radius, said cam being undercut and extending above the last convolution of the preceding layer to a point over substantially the center of such convolution.
.3. As an article of manufacture, a hoisting drum having a helical, rope receiving groove formed in its periphery, a relatively long circumferential lifting ridge formed at the finishing end of the drum, said ridge being formed with a gradually increasing radius for carrying the last convolution of the first layer of rope upon the drum up to substantially the top of such layer, the bottom of a portion of the last convolution of the groove being gradually brought up to the periphery of the drum Where it meets and joins the starting end of the ridge, and a relatively short push-over cam carried on the inner face of the end flange at the finishing end of the drum and located substantially where said ridge is at its maximum radius, said cam extending above the last convolution of the preceding layer to a point over substantially the center of such convolution.
4. The combination with a shaft, of a plurality of drums rigidly mounted upon said shaft, each drum having a relative short push-over cam overhanging the periphery of the drum at the finishing end thereof, the push-over cams of the drums being so located on the shaft that their apices lie in the same plane, said plane being parallel to the axis of the shaft, whereby the drums may be synchronized so that the second layers of cable will be started on each drum at the same time.
5. The combination with a shaft, of a plurality of drums rigidly mounted upon said shaft, each drum having a relative short push-over cam overhanging the last turn of the groove in the periphery of the drum, the push-over cams of the drums being so located on the shaft that their apices lie in the same plane, said plane being parallel to the axis of the shaft, whereby the drums may be synchronized so that the second layers of cable will be started on each drum at the same time 6. The combination with a shaft, of a plurality of drums rigidly mounted upon said shaft, each drum having a relatively long circumferential lifting ridge formed at the finishing end of the drum, said ridge being formed with a gradually increasing radius for carrying the last convolution of the first layer of rope upon the drum up to substantially the top of such layer, and a relatively short push-over cam overhanging the last turn of the groove in the periphery of the drum, the push-over cams of the drums being so located on the shaft that their apices lie in the same plane, said plane being parallel to the axis of the shaft, whereby the drums may be synchronized so that the second layers of cable will be started on each drum at the same time.