US1732485A - Poration - Google Patents

Description

G. T. RONK FAIR LEADER Oct. 22, 1929.

Filed Aug. 15, 1927 fizveiziozf 7M l Ay Patented Get. 22, 1929 UNrr n erase ETNT OFFECE GEORGE '1. RONK, OF CEDAR RAPIDS, IOVJA, ASSZG'NOR TO SPEEDER MACHINERY GOR- PORATION, OF CEDAR RAPIDS, IQVTA, A CORPORATION F IOWA FAIR-LEADER Application filed August 15, 1927. Serial No. 213,134.

signed to support and operate clam shell or drag line buckets.

In the actual operations of cranes in which the clam shell or drag line buckets used, the operator usually imparts rotation to the crane about a vertical axis before the bucket has been lifted from the ground, which causes the lifting cables to be moved against the side flanges of the sheaves, causing undue wear on the sheaves as well as the cables.

t is, therefore, the object of my invention to providea fair-leader, so constructed and arranged that the sheave of the fair-leader will automatically assume proper alinei'nent with the cable so that the said cable will always be properly retained therein without undue wear on the flanges of the sheave.

A further object is to provide improved means for securing the fair-leader to the boom of the crane to prevent bending strain in that portion. of the boom to which the fairleadcr is attached.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects con- 30 templated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 is a side elevation of an excavator having a swinging crane of that type adapted to operate clam shell or drag line buckets, showing the manner in which my improved fair-leader is attached to the crane.

Figure 2 is a (ha-grammatical view illustrating the manner in which the fair-leader adjusts itself to the swinging movement of the cables.

Figure 3 is a plan view of my improved fair-leader and the bracket for supporting the same.

Figure 4 is a detail sectional view taken on the line 4-4 of Figure 3.

Figure 5 is a detail. sectional. view 13: 1-81] substantially on the line of Figure Figure 6 is a detail sectional view taken on the line 6-6 of Figure 4.

The numeral 10 indicates an excavator truck having a platform 11 pivotally mounted thereon to swing about a vertical axis. The platform 11 is provided with a boom 12 pivoted to swing in a vertical plane. Said boom comprises a pair of spaced beams 13 braced together in the usual manner to form a unitary boom member.

The bracket for supporting my improved fair-leader comprises a plate 14 riveted to the top edges of the outer ends of the beams 13. The plate is of a width substantially equal to the width of the boom 12. The upper surface of each of the outer edges of the plate 14 is provided with upwardly extending flanges 15 which extend beyond the outer end of the plate 14 and terminate in arms 16. The free ends of the arms 16 are connected by means of a cross member 17. By this arrangement it will be seen that an opening is formed between the arms 16, the outer end of the plate 14 and the inner edge of the member 17.

Supported on the member 17 is a bearing block 19, and supported on the upper surface of the outer end of the plate 14 is a second bearing block 20, similar to the block 19, and having bearing openings 21. The bearing blocks are detachably secured by means of suitable bolts 22.

The fair-leader comprises a pair of sheaves 23 rotatively mounted on a shaft 24. The shaft 24 is supported by means of a sheave block 25 which comprises a tubular portion 26, the ends of which are rotatably mounted in the bearings 19 and 20. The circular portion of the member 26 terminates in spaced side members 27, between which the sheaves 23 are supported, and in which the shaft 24 is mounted, in the manner clearly illustrated in Figures 3 and 5. The outer edges of the side members 27 are connected by a cross plate 28 the lower edge of which terminates at a point a considerable distance above the lower edge of the side members 27 to form a slot 29 for receiving the vertical strands of the cables 30 for supporting and operat ing the bucket 30, in such a manner that the t ne... ends of the side members 27 will serve as guides to retain the cables 30 Within the groove of the sheaves 23. The sheaves 23 are so located within the side members 27 that their upper faces are substantially in alinement with the pivot center of the tubular members, so-that the strands of the cables 30 may be operated through the inner one of the tubular bearing members. By thisarrangement it will be seen that the sheaves are projected outwardly and beyond the free end of the boom 12, with the center of the shaft 24 substantially in the central longitudinal axis of said boom.

It will :turther be seen that the sheaves 23 are capable 0t oscillating laterally about the center of the tubular bearing members and about the horizontal portion of the cables 30 as a center. this arrangement it will be seen thatthe sheaves arepivotallymounted to swing laterally and capable of oscillation so that the faces of the sheaves will always be supported in planes substantially parallel with .the vertical members of the cable.

By supporting the block25 on two pivot members, with the said block between said members, it will be seen that the load on the hearings will be evenly distributed between said bearings to relieve the bearings of any binding strains due to the leverage, as would be the case if one pivot member were employed.

. The reanends of the flanges 15 are provided with pwardly extending lugs 31, having 1 openings 32 for receivinga cable33, which is employed to elevate and lower .the free end of the boom. Said lugs 31 provide means for attaching cable 33.

Thus it will be seen that I have provided a fair-leader for crane booms in which the sheaves of said leader are free to follow "the lateral movement of the vertical cables, and relieve the cable and the flanges of the sheave of unnecessary wear, and at the same time I have provided an improved means for attaching the boom supporting cables to the boom.

I claim. as my invention:

1. In combination, abraclret'having a supporting plateand comprising a pair of parallel and spaced arms, the free ends of said arms being connected by a cross member spaced from the inner edge of said plate, a bearing supported on the inner edge o'f-said plate, a bearing supported on said cross member, a sheave block supported between said bearing members having tubular portions rotatively mounted in said bearing members, and a sheave rotativelysupported insaid block, the pivot center of said block being tangent with the cable grooveof saidsheave so that one run oi a cable supported by said sheave may project through the center of either of said bearing members, the inner ends'ofsaid arms being provided. with upwardly extending lugs, each of which is provided with a cable receiving opening.

2. In combination, a bracket having a supporting plate and comprising a pair of parallel and spaced arms, the free ends of said arms being connected by a cross member spaced from the inner'odgo of said plate, a

bearing supported on the inner edge of said

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