US2288116A - Snatch block - Google Patents

Description

June 1942.

c. K. STILLWAGQN SNATCH'BLOCK Filed Nov.

Patented June 30, 1942 stares This invention relates to a snatch block.

The invention herein described includes certain improvements over that type of snatch block described in Patent No. 2,235,302 issued by the United States Patent Office tothe applicant herein on March 18, 1941.

An object of the invention is to provide equipment of the character described embodying a frame and a sheave adapted to receive a cable and rotatably mounted on the frame, said frame having one of its side plates hinged and releasably connected with the corresponding end of the sheave spindle, by novel connecting means, and whereby upon release of said connecting means the hinged side plate may be swung to 5 open position to facilitate the mounting of the cable on, or its removal from, the sheave.

Another object of the invention is to provide in a snatch block a novel type of sheaving spine dle anchored to the unitary side plate, in a novel manner, so as to hold the spindle against turning.

It is another object of the invention to provide a swiveling nut loosely anchored to the hinged side plate and which may be readily connected to or disconnected from the corresponding end of the sheave spindle with co-acting means carried by the nut and spindle for centering the nut relative to the spindle to facilitate the connect ing of the hinged side plate to the spindle.

Provision is also made for lubricating the Figure 2 shows an edge view partly in longi- 1 tudinal section showing the hinged side plate secured in closed position.

Figure 3 shows an enlarged longitudinal sectional view, and

Figure 4 shows an enlarged fragmentary side 1 elevation.

Referring now more particularly to the drawing wherein like numerals of reference designate the same parts in each of the figures, the nu meral l designates one of the side plates of the frame. This side plate is approximately elliptical in form and is of unitary structure. The

other side plate is of approximately the same contour as that of the plate I but is formed of two sections, 2 and 3, which are hinged together on the transverse pin 4. Between the stationary section 2 and the plate I there is a swivel block 5 having the end spindles as 6, 6 which extend through aligned bearings of the respective plates and whose outer ends are threaded to receive the nuts I, l. The block 5 accordingly may swivel with respect to the frame. The block 5 has a bearing 8 therethrough to receive the shank 9 of the hook H3. The inner end of the hook is threaded to receive a retaining nut ll thereon whereby the hook It may also swivel relative to the block 5.

There is a sheave spindle [2 one end of which is reduced and fitted through a hole [3 in the plate I. The reduction of said end forms a shoulder which seats against the inside of the plate I as shown in Figured Said reduced end is externally threaded to receive the retaining nut I4 and fitted around said reduced end and clamped between the nut It and the adjacent side of the plate l there is a soft metal washer l5 which is slightly compressed when the nut i4 is screwed home and which serves as a lock to prevent the nut I4 from readily unscrewing.

At one side the reduced end of the spindle i2 is formed with a transverse keyway l6 presenting a flat face IT and opposite this keyway the plate I has an external arcuate countersunk portion 18 into which a correspondingly shaped key It is fitted, said key having a flat face which fits against the face ll. The washer l5 overlaps the key l9 and holds it firmly in place and the key securely holds the spindle 12 against rotation.

Driven onto the spindle I2 and located between the side plates of the frame there is a bearing sleeve 2!] formed of bronze or other similar material on which the sheave 2! is mounted to rotate.

The other end of the spindle i2 is reduced and adapted to be fitted through a hole 22 in the section 3 of the hinged side plate, said reduced end extending beyond said section and being externally threaded and also being provided with an axial socket 23 whose outer end is outwardly flared.

Rotatably mounted on the outer ,side of the section 3 there is a nut 24. This nut has an internally threaded inside socket to receive the corresponding externally threaded end of the spindle l2. The nut 24 is connected to the hinged section 3 of the side plate so as not to become detached therefrom in order that the nut will not become lost in handling the snatch block about the derrick or other place of use. As one means for attaching the nut to the side plate the inner end of the nut may be provided with an external annular rib 25 and welded, or otherwise fastened to the side plate there is an annular flange 26 whose outer margin is overturned forming a rim 2! which extends over the rib 25 whereby the nut 24 is connected to the side plate to swivel and is held against detachment therefrom.

The nut 24 has an inwardly extended stud 28 forming a guide which fits into the socket 23 and serves to guide the nut 24 into proper alignment with the externally threaded end of the spindle l2 so that the nut 24 may be screwed onto said threaded end without the threads becoming crossed. If it be desired to remove a cable from, or place a cable around, the sheave 2|, the nut 24 may be unscrewed. As the hinged section 3 moves outwardly it will move in an are about the pin 4, but the nut 24 being loosely mounted on the section 3 may move in a true axial direction relative to the spindle l2 until its threads have become disengaged from the spindle threads. When said threads are completely disengaged, the section 3 may be swung outwardly so that the cable may be easily removed from, or a cable may be placed around, the sheave 2|.

When the cable has been mounted on the sheave the hinged section 3 may then be swung into closed position and the guide 28 will guide the nut 24 into exact axial relationship with said spindle and said nut 24 may then be screwed onto the threads of the spindle so as to secure the plate section 3 on the spindle end to retain the cable in place.

The drawing and description are illustrative merely while the broad principle of the-invention will be defined by the appended claims.

What I claim is:

1. A snatch block comprising a frame composed of approximately parallel side plates one of which is formed of a fixed section and a hinged section and the other of which is unitary, a swiveling block located between and connected to said unitary plate and the fixed section of the other plate, attaching means on the block, a sheave spindle having extended ends, one of said ends extending through the unitary plate, a nut threaded onto said extended end and securing the spindle to the unitary plate, a key between the spindle and unitary plate efiective to hold the spindle against turning, the other end of the spindle extending through said hinged section and being externally threaded, a nut, means on said hinged section for loosely mounting said nut to swivel, said nut having internal threads adapted to mesh with the external threads of the spindle for holding the hinged section in supporting relation with the corresponding end of the spindle and a sheave rotatably mounted on the spindle between said plates.

2. A snatch block comprising a frame composed of approximately parallel side plates one of which is formed of a fixed section and a hinged section and the other being unitary, means for maintaining the unitary plate and the fixed section together and in spaced relation, a sheave spindle one end of which is secured to the unitary plate and the other end of which is extended through the hinged section and is provided with an internal socket and external threads, a nut, means on the hinged section for loosely mounting said nut to swivel, said nut having internal threads adapted to mesh with I CRAWFORD K. STILLWAGON.

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