US2741458A - Snatch block - Google Patents

Description

F. L. LE BUS, SR

SNATCH BLOCK April 10, 1956 Filed July 6, 1954 INVENTOR BY E L. LeBu5,5/: A TTORNS' Fig. 5

United States Patent SNATCH BLOCK Franklin L. Le Bus, Sn, Longview, Tex.

Application July 6, 1954, Serial No. 441,476

4 Claims. (Cl. 254-193) This invention relates to improvements in snatch blocks and more particularly, but not by way of limitation, to improved means for facilitating the opening and closing of snatch blocks for the handling of the cable.

The present invention contemplates an improvement of present day snatch blocks by providing a swivel latch bolt for the side plates, and having a cam recess adapted to cooperate in a novel manner with a latching ball member so that the ball will be disposed in a locking position of the recess when the latch bolt is unthreaded, thus preventing the loss of the bolt in use, and disposed in another position when the latch bolt is fully engaged to more securely engage the bolt, and thereby facilitating the opening and closing of the snatch block.

It is an important object of this invention to provide a snatch block permitting pivotal movement of one of the side plates to facilitate handling of the cable therebetween.

Another object of this invention is to provide a snatch block wherein the locking means permitting pivotal movement of the side plates is prevented from complete disassociation from the block upon an unthreading thereof.

And still another object of this invention is to provide a snatch block having a pair of side plates through which is disposed a locking bolt permitting pivotal movement of one of said plates in an unlocked position of the bolt in a manner that precludes disassociation of the bolt from the block.

And another object of this invention is to provide a latching means for a pivotal plate locking bolt of a snatch block which provides for two alternate positions of engagement of the bolt so that in one position the latching means assists the locking engagement of the bolt and in another position prevents complete disassociation from the bolt.

Other objects and advantages of the invention will be evident from the following detailed description, read in conjunction with the accompanying drawings, which illustrate my invention.

In the drawings:

Figure 1 is a side elevational view of a snatch block embodying the invention with certain portions cut away and shown in section for clarification.

Figure 2 is an end elevational view of a snatch block embodying the invention depicting certain portions in section for clarity.

Figure 3 is a side elevational detail view of a swivel latch bolt.

Figure 4 is an end view of a swivel latch bolt.

Figure 5 is a sectional view taken along line 55 of Fig. 3.

Figure 6 is a portion of a sectional view taken along line 6-6 of Fig. 3.

Referring to the drawings in detail, reference character 10 represents a snatch block comprising two side plates 11 and 12 with a tie chain 13 afiixed thereto. A sheave or pulley 14 is interposed between the plates and is disposed on a bearing 16 in turn riding on a sheave pin 18 to allow a rotatable movement of the cable receiving sheave 14. The side plate 11 is a movable member utilizing a shaft 20 as a pivotal axis. A swivel latch bolt '22 cooperates with a threaded bore 36 provided in one end of plate 11, for eiiecting a releasing and locking means of the plate 11. A clevis book 28 is secured to a swivel body 30 by any suitable means, such as flange 32 in the usual manner, and the swivel body 30 is interposed between the side plates 11 and 12 at the upper portion thereof (Figs. 1 and 2).

The upper portion of the stationary side plate 12 is provided with an aperture (not shown) for receiving the swivel latch bolt 22. The swivel latch vbolt 22 comprises a head 23 on one end, and a threaded shaft portion 24 on the other end with a non-threaded shaft body 26 therebetween provided with a grooved or slotted portion 25. An aperture 34 in the swivel body 30 is maintained in alignment with the aperture (not shown) in theupper portion of the side plate 12, and the threaded recess 36 by means of an alignment lug 38 thus allowing the swivel latch bolt 22 to be disposed through the apertures with bolt threads 24 engaging threads 36. When the latch bolt 22 is in full threaded position, the body member 26 becomes an axis about which the swivel body 30 is free to pivot, thus allowing the clevis hook 28 to pivot independently of the snatch block 10, thereby alleviating any possible strain during the use of the device.

The swivel body member 30 is provided with an aperture 39 in which is disposed a latching ball 40 and a helical spring 41 encircling a retaining stud 42. The ball isadapted to cooperate with the shaft groove 25 which comprises an elongated cam recess 44 having a shouldered portion 43 at one end and an arcuately shaped recess portion 45 at the other end for a purpose as will be hereinafter set forth.

Operation In operation, the latch bolt 22 during position of engagement and release cooperates with a latching ball 40 disposed in the shaft groove 25 and held therein by a helical spring 41 encircling a retaining stud 42 (Fig. l) disposed in the swivel body 30 at a substantially right angle position to the bolt 22. The latching ball 40 is forced into position against the substantially square shoulder 43 of the recess 25 (Fig. 6) when the latch bolt 22 is in a full threaded position thus preventing the bolt 22 from becoming unthreaded due to vibration. Retrograde movement of the bolt 22 during unthreading causes the ball 40 to move along the taper or cam surface 44 of the recess 25 in a direction away from the shoulder 43 for disposition in an arcuately shaped recess 45 provided conterminous with one end of the groove 25 as the threads 24 of the latch bolt 22 are disengaging from the threaded bore 36 of the side plate 11. In this position of the ball 40, the latch bolt 22 is prevented from being accidentally pulled all the way out and any possible loss thereof. As the bolt 22 is moved into a full threaded position, the ball 40 is forced out of the recess 45 and moves along the tapered surface 44 lodging once again against the shoulder 43 thus being prevented from coming out of the recess 25 and maintaining the bolt 22 in a full threaded position. The shape of the bolt head 23 (Fig. 4) is such as to facilitate the threading and unthreading operation of the bolt.

It will be apparent that the movable side plate 11 is free to pivot about the shaft 20 when the bolt 22 is in an unthreaded position and will rotate downwardly to permit access to the sheave 14 and the cable thereupon. The side plate 11 may be easily restored to a substantially vertical position and with the cooperation of the alignment lug 38 will be held in position to receive the threads Patented Apr. 10,1956- t 7 Q 24 of the latching bolt 22 and thus be held securely in a closed position;

From the foregoing, it will be apparent that the present invention provides a snatch block wherein pivotal movement of one of the plates for operation on the sheave and the cable membersthereof can be easily accomplished without any danger of losing the locking bolt normally holding the pivotal plate in locked position. Furthermore, it will be apparent the latchnig means prevents disasso'ciation of the plate locking bolt from the block itself and also assists the lockingaction of the bolt when in full threaded engagement with the pivotal side plate.

Changesma'y' be made in the combination and arrange mentof parts as heretofore set forth in the specification and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

I claim: I

1. Ina snatch block including a pair of side plates having a pulley member journaled therebetween, a bolt member extending through the side plates and threadedly engageable with one of the plates, a clevis body journaled on the bolt between the plates, a cam recess provided on the outer periphery of the bolt, said recess terminat ing at one end in a shoulder portion and at the oppositeend in an arcua'tely shaped recess, an aperture in the clevis body disposed substantially perpendicular to the bolt, a ball disposed in the aperture and engaging with the recess, spring means cooperating with the'ba'll for resiliently maintaining the ball in engagement with the recess, said ball normally engaging the cam recess adjacent said shoulder portion in a locked position of the bolt, said spring permitting movement of the ball away from the shoulder-upon disengagement of the bolt from the plate until lodged in the arcuate recess to prevent complete disass'oeiation of the bolt from the body.

2. In a snateh block comprising a pair of side plates having a sheave journaled therebetween, a bolt member extending through the said plates and threadedly engageable with one of the plates, one of said plates being pivotal to permit threading of the sheave, a swivel body journaled to the bolt extending through the plate, said pivotal plate having a threaded recess, one end of the bolt enga'geable with the recess for maintaining the plate in locked position, an elongated cam recess provided in the outer periphery of the bolt and latching means provided in the swivel body and cooperating with the elongated cam recess to assist threaded engagement of the bolt with the plate recess, said latching means preventing loss of the bolt from the block body in a non-engaging position of the bolt with the plate recess.

3. In a snatch block comprising a pair of side plates having a sheave journaled therebetween, a bolt member extending through the said plates and threadedly engageable with one of the plates, one of said plates being pivotal to permit threading of the sheave, a swivel body journaled' to thebolt extending through the plate, said pivotal plate having a threaded recess, one end of the bolt engageable with the recess for maintaining the plate in locked position, an elongated cam recess provided in the outer periphery of the bolt, and latching means disposed in the swivel body perpendicular to the bolt shank, said latching means including a spring pressed ball detent which travels along the elongated cam recess in alternate positions of the engagement and disengagement of the bolt engageable with the recess for maintaining the plate in locked position, an elongated cam recess provided in the outer periphery of the bolt, and latching means dis posed in the swivel body perpendicular to the bolt shank,

said latching means including a spring pressed ball detent" which travels along the elongated cam recess in alternate positions of the engagement and disengagement of the 'bolt with the plate recess, said elongated cam recess having an arcuate portion at one end thereof for receiving 1 the spring pressed ball detent in a non-engaging position of the bolt to prevent loss of the bolt from the swivel" body. 7

References Cited in the file of this patent UNITED STATES PATENTS McKissick June 28, 1949 ai -l a l

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