US2551007A - Masthead - Google Patents

Description

F. JONES May 1, 1951 MASTHEAD Filed Dec. 21, 1948 IN V EN TOR.

Attorney:

Patented May 1, 1951 UNITED STATES PATENT OFFICE 2,551,007 I Y Y j v p MASTHEAD Frank Jones, McPherson, Kans. Application December 21, 1948, serial No. 6 ,438.

able hoisting apparatus used in servicing oil wells, and has particular reference to a masthead of the type wherein an upper pulley is mounted on an axis disposed transversely of the axis of a lower pulley.

Heretofore mastheads of the above type have been built so that the upper pulley is situated off to the front side of the mast, thereby imposing a bending strain on and inducing swaying of the mast when handling heavy loads. This creates a distinct hazard to the ground crew because continued bending and swaying of the mast causes the same to crystalize and break off near the masthead.

The primary object of the present invention is to provide a satisfactory masthead in which the upper pulley is mounted directly over the lower pulley and in line with the mast, thereby substantially eliminating bending stress on the mast, reducing its tendency to sway, and increasing its load capacity.

Figure 2 is anenlarged rear elevational viewthereof with the hoist line and pulley block omitted.

Figure 3 is a side elevational view of the construction shown in Figure 2.

Referring in detail to the drawing, 5 indicates a tubular mast having the present masthead mounted on the upper end portion thereof. The masthead includes a pair of similar brackets 6 having their lower portions welded or otherwise rigidly secured to opposite sides of the upper end portion of mast 5 and disposed in spaced parallel relation. The upper portion of each bracket 6 is longitudinally slotted to provide a pair of spaced upwardly projecting arms 1 and 8, the slot 9 being disposed at a slight rearward angle to the mast. Corresponding arms of the brackets are connected by bolts l0 and l l, the bolts I0 extending through spacer sleeves l2. The lower portions of the brackets are provided on their outer sides with spaced longitudinal reinforcing ribs I3, and disposed between and secured to these ribs at the lower portions of the slots 9 3 Claims. (01. 254-439) are aligned hanger blocks [4 in which are secured,

by bolts IE or the like, the ends of a transverse axle [6. A lower pulley I1 is journaled onthe axle l6 between the brackets and guard ribs I8 are provided on the inner faces of the brackets concentricwith axle IE to prevent the hoist line L from jamming between the brackets and pulley in case said hoist line should ride 01f of the latter.

Hanger blocks I9 are respectively secured by the bolts H between the upper ends of arms I and arms 8, and the ends of an axle 20 are secured in said hanger blocks by said bolts. An upper pulley 2| is journaled on the axle 20 and projects through the upper portions of slots 9 and above the arms 1 and 8. Guard brackets 22 are disposedat opposite sides of the upper portion of pulley 2i and have central depending shanks 23 which are outwardly offset and secured to the outer sides of hanger blocks I9 by bolts 24. The ends of guard brackets 22 are connected by bolts 25 extending through spacer sleeves 26, and ribs 21 are provided on the inner faces of these brackets at the top of pulley 2| to prevent the hoist line from jamming between said pulley and guard brackets in case said line should ride off of the pulley. It will be noted that the upper pulley 2| is located directly over the lower pulley l1 substantially in line with the mast, and that it is slanted at a slight rearward angle to the mast. A pulley block 28 is suspended by the hoist line in front of the mast, said hoist line passing over the lower pulley I! to and through the pulley block, then over the upper pulley 2|, and finally being attached at 29 to the pulley block.

The present mast is simple, compact and durable in construction, and the upper pulley is so located and arranged as to substantially eliminate .bending stress on the mast and to permit raising of the pulley blocks substantially to the top of the mast. Modifications and changes in details of construction are contemplated, such as fairly fall within the spirit and scope of the invention as claimed.

What is claimed as new is:

1. In a hoist, a mast, a support mounted on the upper end of said mast, an axle carried by said support transversely of and in line with the mast, a second axle carried by said support and disposed higher than and transverse to the first-named axle and transversely of and in line with the mast, a pulley on each of said axles, the pulley of the second-named axle being disposed directly over the first-named axle and at a slight rearward angle to the mast, said support comprising a pair of similar brackets rigidly secured to opposite,

sides of the mast and disposed in spaced parallel relation, each bracket having a longitudinal slot receiving and extending upwardly from the firstnamed axle and disposed at a slight rearward angle to the mast, each slot defining a pair of spaced arms, and hanger blocks for the secondnamed axle secured between corresponding arms of the brackets, the pulley on said second-named axle projecting through said slots andabove the.

arms.

2. The combination of claim 1 and guard brackets secured to said hanger blocks and disposed at opposite sides of the upper portion of the last-named pulley and extending to the top of said last-named pulley. 7

3. In a hoist, a mast, a support mounted on the upper end of said mast, an axle--carried by saida pair of similar brackets rigidly secured to opposite sides of the mast and disposed in spaced parallel relation, each bracket having a longitudinal slot receiving and extending upwardly from the first-named axle and disposed at a slight rearward angle to the mast, each slot defining a pair of spaced arms, hanger blocks for the secondnamed axle secured between corresponding arms of the brackets, the pulley on said second-named axle projecting through said slots and above the arms, guard brackets extending to the top of said last-named pulley, spaced longitudinal ribs on the outside of said brackets, and further hanger blocks for the first-named axle secured between said ribs at the lower portions of said slots.

FRANK JONES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name: Date 1 ,032,593 Fairbanks -4 July 16, 1912 2,277,386 Brown Mar. 24, 1942

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