US2020920A

US2020920A - Cable equalizer

Info

Publication number: US2020920A
Application number: US738982A
Authority: US
Inventors: Harry H Vanderzee
Original assignee: Westinghouse Electric Elevator Co
Current assignee: Westinghouse Electric Elevator Co
Priority date: 1934-08-08
Filing date: 1934-08-08
Publication date: 1935-11-12
Anticipated expiration: 1952-11-12

Description

5- H. H. VANDERZEE v 2,020,920

CABLE EQUALIZER Filed Aug. 8, 1934 3 46 4 4/ 4/ 1/ 2/ i 7 2x 7-1 I 15 J C 3 1'7 2a 15 l l I 40 [J 4 14, .10

WITNESSES INVENTOR 55;neath the flanged beams (not shown) which Patented Nov. 12, i935 UNITED STATES PATENT OFFICE 2,020,920 CABLE EQUALIZER.

Application August 8, 1934, Serial No. 738,982

6 Claims. (01. 187-1) equalizer are concentrated within close limits so as to keep the spread of the cables to a minimum.

A further object is to provide an equalizer of compact design which will occupy a relatively small space and which can be easily and quickly installed on any existing traction installation using a standard cross head construction.

It is also an object ofmy invention to provide a cable equalizer which will enable more mileage to be obtained fromeach cable, which will prevent excessive cable .and irregular wear in the elevator sheave grooves and which will provide for maximum cabletraction and eflicient operation.

For a better understanding of my invention, reference may be had to the accompanying drawing, in which Figure 1 is a view in perspective of my improved cable equalizer for attaching the hoisting cables of an elevator car to the car structure or to its counterweight.

Fig. 2 is a view takenalong the line IIII of Fig. 1, and l Fig. 3 is a view taken on the line IIL-III of Fig. 1.

The equalizer is illustrated in the drawing as provided with a frame I0 comprising a pair of heavymetal side plates H and i2 mounted on a pair of bars or pipes l3 and M. For ease and simplicity in construction, the bars and plates are connected by passing the bars through a plurality of transverse holes i 5 in the lower portions of the plates. A spacing plate I6 is attached to the bar l3 by a bolt I! in position between the plates H and i2 and a similar plate 18 is mounted upon the bar M by means of a bolt [9, to maintain the side plates at a correct distance from each other.

The bars I 3 and I4 are provided near their outer ends with a plurality of metal clips 2| in order that the equalizer frame may be secured to an elevator car by passing the bars I3 and [4 underusually' constitutes the upper part of the car frame or sling and by then fastening the clips 2! against such flanged portions by means of l a plurality of U-bolts 22.

A first equalizing lever 25 and a second equalizing lever 26 are mounted in the frame It. The first lever comprises two spaced-apart

parallel bars

21 and 28 disposed between the frame plates II and I2. A fulcrum pin 29 passes through the left hand ends of the

bars

21 and 28 and thence through suitable apertures in the side plates II and [2, thereby pivotally mounting the lever between the plates with its free end extending a short distance beyond the right-hand ends of the plates. A pair of cotter pins 30 are disposed in the ends of the pin to hold it in position.

The second lever 26 is of less length than the lever 25 and comprises a pair of spacedapart parallel plates 3| and 32 which are also disposed between the side plates I l and I2 but above the first lever 25. A fulcrum pin 33 passes through the second lever at a point a little to the left of its central portion and then through the side plates H and I2 near their upper right hand ends. The pin 33 is held in position by suitable cotter pins 34. In this position, the second lever is located a short distance above the first lever, approximately parallel therewith and in a vertical plane therewith.

The right-hand ends of the first and second levers also end in'approximately the same vertical plane and are pivotally connected by a link 35; The upper end of the link is disposed between the plates 3| and 32 of the lever 26 and is held in position by a pivot pin 36. The lower end of the link is disposed between the

plates

21 and 28 of the first lever and is held in position by a pivot pin 31. Suitable cotter pins 38 are provided for preventing the pins 36 and 31 from slipping out of their position. As a result of the. connection made by the link 35, any force affecting either lever will also afiect the other lever.

A third equalizing lever 40 of less length than the second lever is mounted upon the first equalizing lever 25 at a point a short distance to the left of the central portion of that lever. The lever 40 comprises a pair of spaced-apart parallel plates ll and 42 disposed between the plates II and I2 of the first lever and held in position by means of a pivot pin 43. The pivot pin passes through the central portion of the lever 40 to give the ends of that lever equal power. Suitable cotter pins 44 are provided to prevent the pin 43 fr0m:slipping out of position.

r A draw-bar 46 is mounted on the left hand end of the lever 40 by means of a suitable pivot pin 49. A similar draw-bar 4! is mounted upon the right hand end of the lever 40 by means of a suitable pivot pin 55.

the drawing, the lengths of the first, second and 7 third equalizing levers and the position of their fulcrum'pins are such that the draw-

bars

46, 41, and 58 are disposedan equal distance apart and are connected to the levers at points in the central portion of the'equalizer.

'Iheupper end of the draw-bar 45 ispivotally V plurality of draft members, a pair of side plates,

connected to a rocker bar 54 by a. suitable pin 59.

. The upper end of the draw-bar 48 is pivotally connected to a rocker bar 55. The upper end of the draw-bar 41 is pivotally connected to a rocker bar 56. Each of the outer ends of the rocker bars is pivotally connected to' a rope or cable socket 5! to which a hoisting cable or other draft member 58 is attached.

7 In operation, if the tension on one of the cables 7 58 attached to the rocker bar 54 increases over that on the other cable attached to that bar, the bar, by reason of its central pivotal mounting will'immediately rotate to a position where the tension on each cable attached to it will be equal. The tension on the cables attached to the rocker bars 55 and 56 will be equalized in the same manher; If the tension on the cables attached to the bars 55 and 55 increases over that applied to the bar 55, the upward pull on the draw-

bars

46 and 41 will exert an upward pull on the first lever 25, which, by the link 35, will exert an upward push, on the right-hand'end of the lever 26 and thereby exert a downward pull on the draw-bar- 48 and consequently the rocker bar 55 until the tension forces are equal.

It will be noted also that if the tension on the rocker bar 54 increases over that on the rocker bar 55, the upward pull on the third lever 40 by the draw-bar 45 willexert such a downward pull on the draw-bar 41 as will equalize the tension between the

rocker bars

54 and 56.

, v and lead upon the driving sheave, the length of I 55 these pairs should be as short as the requirements of the equalizer will permit. A length of approximately seven inches is sufficient if the equalizer is correctly designed. This length will permit a difierence in cable elongation of approximately five inches between cables attached to the same rocker bar. This figure is somewhat greater for two cables not attached to the same upper rocker bar because of the travel available to equalize the bars, by'the first, second, and third levers.

It will also be seen that, by reason of the central position of the draw-bars and the rocker bars, the hoistingcables are centralized in such mannerjthat they willtrack accurately in corthe distance the car would fall in the event of a 7 cable break, and it is important that this be kept to a minimum. Therefore, the equalizer should not be regarded solely as a device for eliminating the necessity ,for cable adjustment. Its purpose should be to notonly equalize the tension. on the cables but also to make visible to the inspectors "5 the fact when adjustment is necessary and to maintain an equal load distribution until the adjustment can be made. 7 Although Ihave illustrated and described only one specific embodiment of my. invention, I' realize 10 that it is susceptible of wide application, and I do not desire to be limited to the precise construction illustrated and described.

I claim as my invention:

1. In an equalizer 'for connecting a body to a V a first 1ever,'a fulcrum pin for pivotally connect ing one end of the first lever to one portion of the side plates, a second lever of less length than the first lever and disposed above the first leverfzo a fulcrum pin for pivotally connectingthe middle portion of the second lever to another portion of the side plates, a third lever of less length f than the second lever, means for pivotally con"- meeting the central portion of the third lever to the portion of the firstlever lying between the fulcrum pins of the first lever and the fulcrum pin of the second lever, a plurality of draw-bars,

one connected to each of the ends of the third i I lever and to the inner end'of the second lever, and a link pivotally connectingthe outer end of the second lever and the free end of the first lever to equally distribute the'load of the body on the draw-bars. 2. In anequalizer for connecting a body to a plurality of hoistingcables, ,a-first horizontal lever, means for'pivotally connecting one end of said leverto said body, a second horizontal lever, means for pivotally. connecting'themiddle portion of. the'second lever to said body; a 40" third horizontal lever, means for pivotally connecting the middle portion of the third lever to a near middle portion of the first lever, a first draw-bar connected to .one end of the third lever, a second draw-bar connected to the other end of the third lever, a third draw bar connected to the inner end of the secondlever, and means for pivotally connecting the outer end of thesecond lever to the free end of the first lever whereby the. load of the body is equally distributed on' the draw-bars. I V v 3. In an equalizer for' connecting an elevator bodyto a plurality of hoisting cables, a' first lever outer end disposed. inapproximately Vertical alinement with the free end of the. firstlever, means for pivotally connectinga near middle portion of the second lever to the body, means for pivotally connecting the outer end of the .sec- 0nd lever and the .free end ofthefirstlever, a thirdlever of less length than the second lever, meansfor pivotally. connecting the central portion ofthe third lever to a near :middle portion 55 of the first lever, a first rocker-bar, a second. rocker-bar, a third rocker-bar, means for corinecting a cable to each end of. each rocker bar,

a first draw-bar pivotally connecting the mide dle portion of the first. rocker-bar to one-end of I the third lever, a second draw-bar pivotally connecting the second rocker-bar to the other end i of thethird lever, and athird draw-bar pivotally connectingthe third rocker-bar to the inner" end of the second lever equally distributing m it load of the body on the cables and maintaining them near the center of the equalizer.

4. In an equalizer for connecting a plurality of hoisting cables to an elevator body, a first lever having one end pivotally connected to the body, a second lever of less length than the first lever and disposed above the free portion of that lever and having its outer end aligned with the free end thereof, means for pivotally connecting the outer end of the second lever to the free end of the first lever, means for pivotally connecting the middle portion of the second lever to the body, a third lever of less length than the second lever, and being disposed with its middle portion below the inner end of the second lever, means for pivotally connecting the middle portion of the third lever to that portion of the first lever lying beneath the inner end of the second lever, a plurality of draw-bars connected respectively to the inner end of the second lever and the outer ends of the third lever, a rocker-bar for each draw-bar, means pivotally connecting the middle portion of each rocker-bar to its draw-bar, and means for pivotally connecting a cable to each end of each rocker-bar for equally distributing the load of the body on the cables and maintaining them in a centralized group.

5. In an equalizer for connecting an elevator body to a plurality of hoisting cables, at first lever pivotally connected at one end to the load, a second lever of less length than the first lever and disposed above the first lever in a vertical plane therewith, means for pivotally connecting the outer end of the second lever to the free end of the first lever, means for pivotally connecting the middle portion of the second lever to the body, a third lever disposed below the second lever, means for pivotally connecting the central portion of the third lever to the portion of the first lever lying below the inner end of the second lever, a draw-bar connected to the inner end of the second lever, a draw-bar connected to one end of the third lever and a draw-bar connected to the other end of the third lever, whereby the load of the body is equally distributed on the draw-bars, and means for connecting the cables to the draw-bars.

6. In an equalizer for connecting a body to a plurality of hoisting cables, a first lever having one end pivotally connected to the body, a sec-- ond lever, means for pivotally connecting one end of the second lever to the free end of the first lever, means for pivotally connecting a portion of the second lever intermediate its ends to the body, means for connecting a cable to a portion of the first lever intermediate its ends, and means for connecting another cable to the free end of the second lever.

HARRY H. VANDERZEE.