US670974A - Snatch-block. - Google Patents

Description

A. B. TAYRBOX.

SNATGH BLOCK.

(Application filed Aug. 16, 1800.1

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ALFRED B.

'IARBOX, OF CHELSEA, MASSACHUSETTS, ASSIGNOR TO THE BOSTON AND LOCKPORT BLOCK COMPANY, OF LOCKPORT, NEW YORK.

SNATCH-BLOCK.

SPECIFICATION forming part of Letters Patent No. 670,974, dated April 2, 1901. Application filed August 16, 1900. Serial No. 27,023. (No model.)

To r/ZZ II/71,077? it may concern.-

Be it known that I, ALFRED B. TARBOX, a citizen of the United States, residing at Chelsea, in the county of Suffolk and State of Massachusetts, have invented a new and useful Improvement in Snatch-Blocks, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification, in explaining its nature.

The invention relates to a snatch-block having the head which carries the hook pivoted to one of the cheeks and detachably secured to the opposite cheek, wherebythe head and book are adapted to be unlocked by hand from one cheek and turned over upon the other cheek to expose the sheave and permit the removal of the sheave-rope and whereby also the head is adapted to be moved back by hand to close the block and at the end of said movement to make automatic engagement with the other cheek, whereby it becomes latched or locked to it.

The invention consists in latching or looking devices which engage each other because of the movement of the head to locking position and without the aid of an accessory closing device, like a spring.

The invention further comprises various features of construction and organization, all of which will hereinafter be fully described.

Referring to the drawings, Figure 1 is a view of my improved snatch-block in edge elevation, the hook-head being represented in its locked position. Fig. 2 is a view of the snatch-block, partly in elevation, but principally in vertical section, on line 2 2, Fig. 3. Fig. 3 is a view in elevation of the side of the snatch-block with which the hook-head makes latching or locking engagement, the hookhead being in its locked position. Fig. 4 is a view of a portion of a block in edge elevation to represent the hand movement of the latching orlocking devices necessary for unlatching the hook-head from the cheek. Fig. 5 represents the same parts with a portion of the hook-head looking or latching devices shown in dotted outline to represent the position to which they are moved to permit of the full release of the hook-head from them preparatory to swinging it over to the position represented in Fig. 6. Fig. 6 is a View of the same parts, representing the hook-head as fully unlatched and thrown over to open the block and permit the removal of the sheave-rope and also showing the part which I will hereinafter call the catch as in normal unlocked position or the position which it occupies prior to the engagement of the latch upon the hook-head with it.

Before describing the invention in detail I would say that I shall hereinafter term the part of the hook-head which makes detachable engagement. with the check of the block the latch and the part of the check which makes detachable engagement with the hookhead the catch. 1 would further say that the engagement of the latch with the catch is of a positive character in that the movement ofthe head to close the block causes the latch to be brought into contact with the catch and to then move the catch from its inoperative position (represented in Fig. 6) toits operative position. (Represented in Figs.1,2, and 3.) This is accomplished by providing both the latch and the catch with engaging surfaces in the nature of inclines or cams which upon contact with each other, due to the movement of the hook-head latch against the catch, causes the catch to be moved from its outward inclined position (represented in Fig. 6) to its in ward inclined position, (represented in Fig. 4,) the hook-head having then been moved beyond its normal closed position, (see Fig. 4,) when it is lifted to lock the catch, and the parts then assume the latched and locked positions. (Represented in Figs. 1, 2, and 3.)

Referring to the drawings, A represents the cheek of the block to which the hookhead F is pivoted.

B is the cheek to which the catch H is pivoted.

C is the block-sheave, which is mounted between the cheeks upon the pivot-bolt D, which fastens the two cheeks together. Each cheek has the housings A B, respectively, which are shaped to provide the rounded outer surface a, the outer central bosses a, the outer depressions a between the rounded surface a and the bosses, the inner cavity a the inner boss 0%, relativelyenlarged, having the circular bearing-wall a surrounding a central cavityafl-the circular rope protecting and guiding corner a of the outer edge of the cavity a the upwardly-extending arms a a having the openings a between them, the strapholes a, and ct through-the top of the housings and through the central portion thereof between the inner and the outer bosses, and the ears or feet a at the lower end of the housing, which abut, are riveted together and permanently close the lower portion a of the sheave-ropeway. The housings are preferably made of;cast or malleable iron,

although they may be formed by drop-forging. Each cheek also includes a strap 'of bar-iron folded at the center of its length and having H is pivoted by the pivot h to the strap E. The hook-head has mounted upon it, to swivel thereon, the usual hook G. Its

latch Ihave lettered f, and it is'of course at the free end of the head F. It comprises a hook having the curved upper edge f extending to the vertical shoulder f, the catchseatf and thelatching cams or inclines f Two cams or inclines preferably are em-- ployed, although one only is necessary, and

they are arranged one upon each side of the latch,.being preferably cast thereon to project outwardly from the side .faces of the latch. They are shaped to engage cooperating owns or inclines'upon the catch and by said engagement to cause the catch to be moved from the position represented in Fig. 6 to the position represented in Fig. 4: or to their inner ends, when the latch may bemoved upward and away from the ca'ms orinclinest of the catchto permitthe slight return movement of the catch to the position represented in Figs. 1 and 2 and the engagement'ofthe locking projections upon the catch with the cams or inclines. The catch H is in theform ofa link, and it has at its upper end a crossbar h, which engages the seat of thelatching portion of the hook-head within the shoulder.

(See Figs/1 and 2.) 'It also has a central opening 72. between its arms h h, which is of a-width greater than the width-of the-latch and in which opening the latch is movable 'when making its engagement with the link.

The lower ends of thelink-arms arepivoted to the upper end of the strap in amanner to permit the catch to be moved-outward and inward with respect to the-opening between the arms a a of the housing. From the inner side of each of the link-arms there ex- The straps are:

tends intothe link-opening the cams or inclines 71 which cams or inclines are oppositely arranged with regard to each other and are of the same shape,being curved or rounded upon their upper surfaces, as represented in Fig. 2. There are also extended inward from the arms the latch-locking stops or lugs 71, which are above the cams or inclines. In order that the said catch l-I may be maintained in theinclined position shown in Fig. 6 and be prevented from falling out of this position,

which is necessary to insure an automatic engagement of the said catch H and latch F when the latter is thrown over to locking position, the'said catch H has thelower ends of its side arms 7L3 7L projected a little below the .pivot f so that the projecting ends 71, will impinge against the outside of the cheek pieces of the block when the catch is released and hold said catch in the inclined po sition shown in Fig. 6, and since it cannot drop outof the reach of latch F the parts are always-in proper relation for automatic coupling.

The operation of latching or locking the hook-head is as follows: The partsviz., the hook-head and the catch-when disengaged occupy the positions with respect to the cheeks represented in Fig. 6. The sheave- -=rope having been placed between the cheeks of the sheave, the hook-head is then turned over from the position represented in Fig. 6 to the positionrepresented in Figs. 4 and 5- that is, it is caused to be moved beyond its normal locked position. (Represented in Fig. 1.) Thiscausest-hecams orinclinesof itslatch to come into contact and ride upon the cams or inclines upon the catch, the outer ends of the latch cams or inclines first coming into contact with the inner ends of the catchcams or inclines, and the catch is thereby moved from the .position represented by full lines in Fig. '6 and dotted lines in Fig. 5 to the position represented by full lines in Fig. 5 and in Fig. t-that is, it is moved from an outward inclined position at the outer end of the latch'cams or inclines to an inner inclined .position at or slightly beyond the inner ends of the latch camsor inclines, the camsor'inclines of the-catch being thus caused to travel thefull length of the camsor inclines of the latch andto thus be at the ends of said cams or inclines oppositet-hat from which they were at the beginning ofthe engagingmovement. As the catch cams or inclines have thus cleared the latch cams or inclines, it follows that the hook-head may then be lifted from the position represented in Fig. at to the position represented in Figs. 1 and 2, thereby bringing the hook-seat into contact with the cross-barof the catch and also by the incline f beyond the catch-seat, moving the catch backward to the vertical position (represented in Figs. 1 and 2) and at the same time bringing the latch stops or locks h beneath the latch cams or inclines, (see Figs. 1 and 2), thereby locking the hook-head in its normal position and also looking the catch to the latch, with the catch-bar in the hook-seat on the hook-head. The catch-link is then in line with the cheek-strap, to which it is pivoted. This engagement of the hook head latch with the. cheek-catch and the subsequent locking of the latch and catch are entirely produced by the throwing over from open position to a position beyond the closed position of the hook-head and by the movement of the hookhead backward from this position to its normal closed position. The hook is used as a handle in giving the hook-head these movements 3y referring to 1 and 2 it will be seen that the cams or inclines of the catch are then quite a distance below the cams or inclines ot' the latch, the said last-named cams or inclines being separated from the former, by the backward or upward movement of the hook-head. To release the hook-head from the cheek A and its catch for the purpose of releasing the block from the sheaverope, it is necessary to move the catch from the position represented in Figs. 1 and 2 inward to the position represented in Fig. 4. This moves the latch-locks 77, inward from beneath the latch cams or inclines and permits the hook-head to be swung downward to the position represented in Fig. 5, the inner ends of the latch cams or inclines clearing the outer ends of the latch-locks, and the catch may then be moved from the inclined position represented by full lines in 4 and 5 outward to the position represented by dotted lines in Fig.5 and the full lines in Fig. 6. The catch is then so disengaged from the latch that the hook-head maybe swung away from it without further moving it to the position represented in Fig. 6. I do not limit this part of the invention to its use in connection with a block the cheeks of which are composed of housings and straps, but may use it in conjunction with any form or construction of cheeks.

It will be seen that the straps are held removed bythe housings from the hub and sides of the sheave and that portions of the housings in line with the sheave are interposed between the straps and the sheave. It will also be seen that the sides of the sheave and narrow faces of these interposed sections bear against each other, so that the sheave has side bearings as well as a bearing on the pivotbolt.

The chambers within the housing-bearings may contain a lubricant.

The inner surfaces of the arms a a are somewhat oifset from the corner a to provide a good clearance for the sheave-roll.

Having thus fully described my invention, I claim and desire to secure by Letters Patent of the United States- 1. The combination with a snatch-block having cheek-pieces, of a hook-head pivoted to one of said cheek-pieces at one end, a catch pivoted to the other of said cheek-pieces, means to limit the outward movement of said said catch when the hook-head is thrown to locking position.

2. The combination with a snatch-block having cheek-pieces, of a hook'head pivoted to one of said cheek-pieces. a catch pivoted to the other of said cheek-pieces and provided with means which limit its outward movement, and engaging means on said hook-head to automatically engage and interlock with said catch when .the hook-head is thrown to locking position.

3:3. The combination with a snatch-block having cheek-pieces, of a hook-head pivoted to one of said cheek-pieces, a catch pivoted to the other of said cheek-pieces and having projecting stops to limit its outward movement, and engaging means on said hook-head to z'tutoinaticaliy engage and interlock with said catch when the hook-head is thrown to locking position.

4. The combination with a snatch-block having cheek-pieces, of a hook-head pivoted to one of said cheek-pieces, a catch pivoted to the other of said cheek-pieces, said catch having projecting lower ends which impinge against the outside of the cheek-piece and limit the outward movement of said catch, and engaging means on said hook-head To automatically engage and interlock with said catch when the head is thrown to locking position.

5. The combination with a snatch-block provided with a hook-head pivoted at one end to one cheek of the block and having a latching portion at its free end, of a catch attached to the other cheek ot the block, said catch being movable from an open to a closed position upon contact with it of the latching portion of said hook-head.

6. The combination with a snatch-block, of a hook-head pivoted at one end to one cheek of the block and having a latching portion at its free end, a catch attached to the other cheek of the block, said catch being movable from an open to a closed position upon contact with it of the latching portion of said hook-head, and means to lock said hook-head and catch together when in closed position.

7. The combination with a snatch-block, of a hook-head pivoted at one end to one cheek of the block and having a latching portion at its free end, a catch attached to the other cheek of the block, said catch being movable from an open to a closed position upon contact with it of the latching portion of said hook-head, and means carried by said catch to lock said hook-head and catch together when in closed position.

8. The combination with a snatch-block, of a hook-head pivoted at one end to one cheek of the block and having a latching portion at its free end, a catch attached to the other cheek of the block, said catch being movable from an open to a closed position upon contact with it of the latching portion of said hook-head, and a locking device for said latch carried by said catch and movable by said hook-head into locking engagement with said latch.

9. In a snatch-block, the combination with a hook-head pivoted to one check of the block, said hook-head being provided with a catchreceiving seat and catch-closing devices to move the catch from open to closed position at its free end, of a catch pivoted to the other check of the block and provided with a portion to engage the seat in said hook-head, and means on said hook-head to cooperate with the said catch-closing means.

10. In a snatch-block, the combination with a hook-head pivoted at one end to one check of the block and having a catch-receiving seat at its free end, a catch pivoted to the other check of said block, means to move said catch from an open disengaged position into closed position and in engagement withsaid hook-head, and a lock on said catch to hold it in engaged position with the hook-head.

11. Inasnatch-hlock, the combination with a hook-head pivoted at one endto one check of the block and having a catch-receiving seat at its free end, a catch pivoted to the other check of said block, means carried by said hook-head to engage and move said catch from an open disengaged position into closed position and in engagement with said hookhead, and a lock on said catch to hold it in engaged position with the hook-head.

12. In asnatch-block, the combination With a hook-head pivoted at one end to one cheek of the block and having a catch-seat formed in its free end, of a catch pivoted to the other cheek of said block, means on said hook-head to engage said catch and move it from open to closed position, means to lock the catch in the catch-receiving seat of the hook-head, and means to lock the hook-head in position upon movement of the catch ina reverse direction.

13. In a snatch-block, the combination with a hook-head-pivoted toone cheek of the block and having a latching portion at its free end,

yond its normal closed position and then back to its normal closed position to lock said hook-head.

14:. In asnatch-block, the combination with a hook-head pivoted to one check of the block and having a latching portion at its free end, a catch pivoted to the other check of said block, said catch being movable from an open to a closed position upon contact therewith and being further movable inward from its normal closed position and outward to disengage it from said hook-head.

l 5. In a so atch-block, the combination With a hook-head pivoted to one check of the block and having a latching portion at its free end, catch-operating cams or inclines on said latch portion and a catch pivoted to the other cheek of said block, said catch having alatchengaging bar and cams or inclines to cooperate with the cams on said hook-head.

16. In asnatch-block, the combination with the housings A, B, having the arms a, a of the straps E, E, extending into the opening between the arms, a hook-head pivoted to one of said straps and having catch-closing devices thereon, a catch pivoted to the other strap and having hook-head-engaging means, and means'for locking'said hook-head.

17. In asnatch-block, the combination with housings A, B, having strap-openings formed therein, straps E, E, passing through said openings, portions of said housings lying outside of said strapsand portions inside thereof to form side bearings for the sheave, a sheave, a hook-head attached to said strap, and a bolt D passing through said straps, housing and sheave.

ALFRED B. TARBOX.

In presence of- J. M. DOLAN, M. D. NEVVMAN.-

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