US929508A - Hoisting appliance. - Google Patents

Description

uNITED STATES .PATENT oFFicE.

AUGUSTUS SMITH,'OF NORTH PLAINFIELD, NEW JERSEY, ASSIGNOR -TO BERGEN POINT IRON WORKS, OF NEW YORK, N. Y., A CORPORATION O1" NEW JERSEY.

noxs'rme APPL'IANCE.

Patented July 27, 1909.

Application led November 6,1908. Serial No. 481,387.

To all 'whom 'it may concern.:V

Bc it known that I, AUGUSTUS SMITH, a citizen of the United States of America., residing in the city of North4 Plainfield, in the county of Somerset, in the StateA of New Jersey, have invented a certain new and useful Improved Hoisting Appliance, of .which the fol owing is a specification.

-The main object of my invention is to so construct a drum and combine therewith a hoisting rope and pulley block that the total hoist or path through which the load, as for instance a skip or umping bucket, is lifted, is limited absolutely by the shape of the drum itself and is not dependent on stopping the revolution of the drum, when the skip or bucket reaches the upper cr lower1 limit of its travel. -This object I attain by the construction and combination hereinf after described.

In the accompanying drawings the four fivures are similar 'diagrams of four of the different forms in which my invention may be embodied.

The ski dumping bucket or other weight to be lifte through a path of denite length is represented -by the weight marked W in the accompanying drawing. This weight is suspended from a flying block hanging in the bight of a rope, the two ends of which are so wound on a grooved drum 'or on separate drums, that as the drum or drums revolve, one end ofthe rope is paid out while the other end is wound in. The drum or drums is or are made of differing diameters and the ends of the rope are so coiled thereon that at the beginning of the motion the rope is paid out at eXactly the same speed at which it is wound in, and the bucket or other load consequently remains at rest, the shea-ve in the flying block F merely turning with the rope. But after a prescribed number of revolutions of the drum, depending upon the circumstances of the case, the rope will run onto a groove of the drum of increasingor travel of the skip or other'load IV is reached, the diameter of the groove upon which the rope is being wound 1n graduallydecreases atv any desired rate until the rope is again being wound in at the same s eed at which it is paid out at the other en at which'time the skip, bucket or weight will be brought to rest at the up er limit of its travel without stopping the drum.

If the drum be of limited length, its revolution must `be sto ped soon after the bucket reaches the en of its travel, because the rope remaining on the drum to be paid out will soon all be paid out. The revolution of the drum can be stopped automatically or b a human o eraton- 'The stopping of the rum. has notliing to -do with the stopping of the skip or bucket, except for the practical limits of construction above noted.

In Figure 1 the grooved drum D is mounted on a shaft S, which can be revolved by a pulley, gear wheel or other means at I. This drum is Shownx as with a shortisgirally grooved part 1 of small diameter, le ing to a part 2 of gradually increasing diameter, a

part 3 of large diameter, la gradually decreasing part 4, and a relatively long part 5 of the same diameter as the part l.

. One end of the hoisting rope R1, R2, in the light of which the iying block F with its weight is suspended, is secured to the end of the small diameter l, while the other end is wound on the small diameter 5 of the drum illing as many grooves as the drum will make rotations. -In the diagrams, the rope is shown wound only on the two small and equal diameters l and 5 of the drum, so that as the latter is revolved, the part'R1"`is being -wound onto the diameter 1 at the same rate of speed at which it is being paid oli the diameter 5. As the revolution of the'drum D continues in the direction indicated by the arrows,lthe part R1 of the rope will risey in the spiral groove at 2, being wound in faster vand faster as the radius increases, while the part R2 will be paid out froml the diameter 5 at a uniform s eed. As R1 is wound in on the portion o the drum at 3, it will be drawn in at a rate of speed uniformlypgreater than R2 -is being paid out in unwindng from 5. As the weight or skip reaches the upper limit of its travel R1 will be wound in on the spiral at 4 with a gradually decreasing radius, causing the, load to be broughtgradually to rest until when R1 reaches the groove at 5, the upward motion of W will cease entirely. If the drum were indetnitely extended to the right, it is obviousthat the revolution of the drum could continue without causing thezweight W to rise further. I t is evident that the same resuit would ensue if, after starting the revolution of the drum, the rope had been so wound that one end, as R2 began to be paid out more slowly than the other end was wound in. In other Words, the rate of paying out the rope could be decreased instead of the rate of winding increased. In the construction, Fig.' 1, this condition would obtain if R2 were wrapped around the drum to the left hand end of diameter 4, while R1 began at the left of the diameter 3. It the drinn were revolved, with this condition in the same direction as before, R1 would be wound in uniformly as it traveled from left to right en diameter 3, While R2 would be paid out more slowly as the radius of thc spiral on which it was Wound, decreased to 5. The weight would then be raised at a uniform speed as before until R1 reached diai'neter 4, where the rate of lift would be decreased as R1 was wound in on the decreasing radins of this spiral 4 until R1 reached 5, after which it would be wound in at the same speed that R2 was paid out as be't'ore, and the upward motion o't' lV would cease. Ay extending the drum D1 further, as shown in the diagram Fig. 2, on which the same parts are represented by the same letters, so that after the outgoing rope R2 reaches the end of 5, it begins to be paid out faster as it unwinds from (S to 7, while R1 is being wound in on 5, the weight or skip W will begin to descend or return at a gradually increasing velocity, until R2 reaches the maximum diameter o'l" the drum at 7, at'ter which, il the drum is there made cylindrical, the rate o't' descent will be uni'lorm, while R2 is being unwound from 7, at the same time that R1 is being wound in on 5. As the bucket or skip W reaches the lower limit of its travel, R2 is paid out on the spiral of gradually decreasing radius, thereby bringing `the weight or skip gradually to rest until R2 reaches 9 where the diameter is the same as 5. The length of groove on 5 is so taken that R1 will not have passed therefrom by the time R2 reaches the' end vof t), and the skip or Weight will, therefore, be brought absolutely to rest at the bottom of its travel without stopping the revolution of the drum. The drum can then be stopped, as before, by some automatic device or by an attendant.

In the case shownin Fig. 1, the bucket,

v skip or weight can be returned to itsstarting point by reversiny the direction of rotation when the cycle oit operations will obviously be reversed.

In the case shown ill Fig. 2, it'4 the total increase In the length of the groove `from l to 5 over the length et thelsame number of coils on the cylindrical portion 5 is exactly the sam'e as the increase in the total length of the groove from the end .ot' 5 to the beginning of t) over the same cylindrical portion 5, the bucket, skip or weight will, after rising and pausing for a prescribed time (depending on thelesign of the drum) return again exactly to the point of starting without stopping the rotation of the drum. ln this case in order to repeat thelcycle, the direction ot the rotation of the"l drum must be reversed at each allernate/rouml trip of the skip or weight, lV. It-lis not necessary that both ends of the rope R1 and R2 should be wound up on ditlerent portionsl ot' the same drum, as the same result can be secured where R1 is wound upon a drum l)2 mounted on shaft S1, while R2 is unwennd trom another drmn 1) mounted on sha t't S2, as illustrated in Fig. it, provided the drums be revolved synchronously by means ol gears, as indicated by the toothed wheels, l, l2, l, or by other means to accomplish the same result.

ln the case shown in ltig. the diameters of the grooves "at 1vl and at t3 must. be the same (it the drums revolve at the same speed) in order that the skip or weightl may remain at rest at the commencement ol' the `revolution ol the drum, and the diameters and t3 must. smnlarly be the same it the skip or weight is to remain at rcst at the upper limit. ot' its motion, while the diameter at 5 must be the same as at l() it thc skip or weight is to remain'iat` rest on its return to its starting lpoint prior to the stopping olE the drums.

l'Vherethere is no mcchanimll objection to suspending the skip or weight W in the bight. otE an endless rope as shown in l `ig. l, the cycle of operations zuftannplislual by the arrangement shown in Figs. 2 and 25, can be acconiplished with a slightly simpler forni ot drum, having one swell 3. In this case the rope is wound so that at the commencement of the revolution R1 is wound on at the same -ate as R2 is paid out on the same;

`higher rate of speed than R2 is paid out along 1, so that. the bucket or weight \V will be drawn upward toward the drum, until R' reaches the spiral of descending radius at 4, and the ascending of the skip or bucket llt) will be gradually checked until it ceases,

A. when Rl-has reached 5. If the 'diameters l and 5 be equal, the skip or Weight will remain at rest at the upper limits of the travel until the continued revolution of the drum begins to pay off the rope R2 on the spiral of increasing radius at 2, Whenthe bucket In this case the cycle can be repeated by reversing the direction`Il of the rotation of thesome more convenient point than directly` drum.

. It is obvious that the rope R1 and R2 can be led over guide sheaves, if desirable, so that the hoisting drums may be placed at over the Weight to be lifted. It is obvious also that the relative diameters and arrangements ofthe small and large portions ofthe drums With' their lconnectlng spirals, may

be 4arranged in a number of Ways to meet varying conditions.

I claim as my invention-.-

The combination of a spirally grooved hoistin eters With a yrope and a lifting pulley block drum or drums of varying diamina bight of the rope, the ends of the latter being secured to and Wound on the different parts of the drum or drums, substantially as described, whereby at the commencement of rot-ation the sheave of the lifting pulley block turns but the load remains at rest, then the load gradually does acquire motion as the rotation ofthe drum continues and subsequently isbrought to 4rest at a predetermined point, depending solely on the physical proportions of the drum or drums and independent of the exact time of stopping the rotation thereof.

In testimony whereof I have signed my 'name to this specification, in. the presenceof two subscribing Witnesses.

` AUGUSTUS sMr-rri.

Witnesses: WALTER ABBE, HUBERT I-IowsoN.

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