US2142354A - Governor cable take-up - Google Patents

Description

Jan. 3, 1939.

T. c. HARPER GOVERNOR CABLE TAKE-U1" Filed May 3, 1957 I INVENTOR.

7/20/7745 Qfla/per ATTORNEYS Patented Jan. 3, 1939 UNITED STATES PATENT OFFICE GOVERNOR CABLE TAKE-UP Ill.

Application May 3, 1937, Serial No. 140,468

1 Claim.

This invention relates to elevators and particularly that type employing a cable suspended cab or cage that is raised and lowered in an elevator shaft and which has as a part of its operating equipment a governor cable which is suspended in looped fashion so that the bight is at the bottom or in the conventional pit of the elevator shaft.

The primary object of this invention is the pro- '10'vision of an automatic takeup structure for the governor cable of elevators which structure embodies uniquely arranged elements whereby the governor cable is engaged at the bight thereof and yieldably held in a taut position.

Another important aim of the instant invention is to provide governor cable takeup structure which has means for engaging the bight of a governor cable and for yieldably holding the bight in one of a number of positions all in accordance with the amount of stretch imparted to the governor cable during work.

A large number of elevator governor cable takeup mechanisms have been employed commercially in an effort to overcome the well known objectionable slap that occurs in the elevator cable after the same has been once installed and after continued use has established a large amount of play that is not compensated for by the conventional elevator mechanism. Ordinary Weights which have been hung at the bight of elevator governor cables have been used for a long time past but such weights do not overcome the wear on the governor cables which is occasioned by the presence of an excessive amount of play in 5 the cable which invariably develops after strain has been imparted thereto through the ordinary operating routine.

This invention, therefore, contemplates the employment of novel means for yieldably main- 4() taining a pulley wheel in engagement with the bight of a governor cableso that as the cable lengthens due to work, the same amount of yieldable pressure will always be imparted regardless of the degree or speed of stretch and without 5 attention of a maintenance man.

Minor objects of the invention which will include specific embodiments of one form of the invention willappear during the course of the following specification, referring to the accompany- 50 ing drawing wherein;

Figure 1 is a side elevation of an elevator governor cable takeup structure made to embody the present invention.

Fig. 2 is a vertical sectional view through the 55 structure taken on line II-II of Fig. 1.

Fig. 3 is a top plan view of the structure shown in Fig. 1, and,

Fig. 4 is an enlarged, fragmentary, detailed sectional view through a portion of the takeup structure taken on line IVIV of Fig. 2. 5

The governor cable 6 which forms a part of the elevator mechanism is looped at the bottom of the elevator shaft to present a bight wherein rides the conventional pulley wheel 8. There is always a certain amount of variation in the pre- 10 cise position of the bight and accordingly pulley wheel 8 must give and take as required. It is always customary to have pulley 8 removably mounted so that vertical travel may be had to compensate for the conditions just mentioned 5 and which are well known. In the instance shown pulley wheel 8 is rotatably mounted in the weighted wheel frame I!) through the medium of transverse pintle I2 that is carried by opposed members I4 of said frame ll]. 20

The structure provided to present tracks l6 along which frame It] may ride is in the nature of an open frame work including an upper and a lower support arm l8 and 20 which may be mounted upon a part of the elevator track 22 or 25 anchored to any other relatively stationary and solid member in the bottom of the elevator shaft. The weighted wheel frame I0 is confined between tracks 56 and may move vertically there-between as the tracks preclude lateral displacement. 30

A ratchet bar 24 extends vertically beside frame In and isprovided with a plurality of teeth 26. The lower end of bar 24 has a foot 28 turned therefrom to overlie bottom support arm 20 and to rest thereon thereby to preclude any downward movement of bar 24 when foot 28 is in the position illustrated in Fig. 2. A bolt 30 extends through an opening formed in foot 28 and through a hole 32 provided in arm 20. The length of this bolt 30 may vary in accordance with conditions met and a spring 34 of suitable strength is coiled about bolt 30 so that one end bears against arm 20 while the other end engages washer 36 held in place by nut 38. Thus it is apparent that upward vertical movement by bar 24 may occur so long as the upward force imparted thereto is sufficient to overcome the strength of spring 34.

Wheel frame ID has a bracket 40 secured thereto as clarified in Fig. 4. This bracket 40 has opposed outstanding ears between which is mounted a dog 42 that is specially formed to engage teeth 26 of bar 24. This dog is bifurcated at its free end as at 44 so that there is presented a projecting portion that is disposed on each side of bar 24. The other end of dog 42 is curled to present a bearing as shown in Fig. 4 which bearing has a bolt 46 extended therethrough so that free rotary motion might occur. This movement however, is limited by a stop 48 so that the dog will always remain in such a position as to require the action of gravity to move it against teeth 26 of bar 24. Teeth 26 are so formed as to permit dog 42 to ride'thereover when the pulley wheel and frame 8 and I0 respectively are traveling downwardly but when an upward movement occurs dog 42 tightly engages one of the teeth 26 so that any such upward movement is manifestly opposed by the tension of spring 34. Thus it will be clear to one skilled in the art that as governor cable 6 lengthens to permit its bight to gradually lower, the dog 42 which is carried by frame 10 will move down along bar 24 to progressively engage the teeth 26 formed therein. After the frame has been lowered to a point for example as shown in the drawing, any upward movement on the part of the bight of cable 6 would be opposed by spring 34 because of the relation between the elements. 7

Wearing of cable 6 because of an excessive amount of slack due to play therein will be overcome and it has been found through actual use of this structure that the cable life is prolonged, the strands thereof are not broken as a result of inner engagement with each other due to the looping of the cable and that a smooth action is always insured when the elevator cab is stopped.

It is conceivable that governing structure for elevator takeup cables which embody this invention might be made to present a physical appearance much difierent from that illustrated and it is desired to be limited only by the spirit of the invention and scope of the appended claim.

I claim:

In an elevator governor-cable assembly having a pulley wheel in the bight of the cable, a vertically movable frame rotatably supporting the pulley wheel to move therewith as the bight of the cable raises and lowers, and a stationary guide with spaced apart guide tracks for the frame, a vertical bar provided with ratchet teeth, carried by the guide substantially midway between said tracks and disposed beside a portion of the frame; a spring having connection with the guide and with said bar to yieldably hold the bar in a normal position for longitudinal movement upward; ly from the normal position; and a dog mounted on the frame in engagement with the ratchet teeth of the bar, said teeth and dog being formed and disposed respectively so as to cause the frame, dog and bar to move upwardly together when the spring yields under the action of the governorcable and to cause the dog and frame to move downwardly independently of the bar when the same is in the normal position.

THOMAS C. HARPER.

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