US235222A

US235222A - Snatch-block

Info

Publication number: US235222A
Authority: US
Publication date: 1880-12-07
Anticipated expiration: 1897-12-07

Description

(No Model.)

T; R. FERRALL. A Snatch Block. No. 235,222.

Patented Dec. 7,1880.

N. PETERS, PHOO-LITIICGRAFHEH, WASHINGTON. CA

UNITED STATES PATENT OFFICE.,

THOMAS R. FERRALL, OF BOSTON, MASSACHUSETTS.

SNATCH-BLOCK.

SPECIFICATION forming part of Letters Patent No. 235,222, dated December 7, 1880.

Application filed August 19, 1880.

To all whom it may concern Be it known that I, THOMAS B. FERRALL, ofthe city of Boston, in the county of .Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Snatch- Blocks, of which the following is a full, clear, and exact description.

This invention relates to improvements in the construction of snatch-blocks, although the same are applicable in some respects to other forms of pulley-blocks; and it consists, first, in a snatch-block having its hook pivoted or journaled to one cheek, and a link hinged to the other cheek, said link being adapted, by its free end, to pass over the end of and embrace the other pivot or journal of said hook and to be secured thereto by an arm or lip of said journal; second, in a snatchblock provided with closed hollow cheeks, each consisting of a hollow cast-metal shell formed with rounded edges, the said cheeks being connected together by a cross-bar at their lower extremities, and the journals of the pulley-Wheel being passed through the several walls of the hollow cheeks; third, in the combination, with the two hollow castmetal cheeks in a snatch-block, of two straps inclosed within the hollow shells constituting the cheeks, one strap being extended out from one of the cheeks to form an eye for the hinged link, the other strap being formed to provide a bearing for one of the journals of the hook, and both of the said straps being made with bearin gs for the journals of the pulley-wheel, all as hereinafter described.

ln the accompanying plate of drawings this improvement in snatch-blocks is illustrated, Figures l and 3 being edge and side views, respectively, of a snatch-block with its hook Fig. 2, a vertical section on line x Fig. 3; Figs. 4 and 5, vertical sections, respectively, of the two cheeks; Fig. 6, a horizontal crosssection on line y y, Fig. 3, with the pulley removed; Fig. 7, a plan view below line z z, Fig. 3, with the pulley removed.

ln the drawings, A represents a snatchblock constructed according to this invention, in which B B are the cheeks, connected together at the bottom by a crossbar, C, and D 5o the pulley, adapted to turn on its journal E.

The cheek B' extends higher than `the cheek (No model.)

B, leaving the opening or snatch F, as usual in snatch-blocks. The block A, composed of the cheeks B and B and cross-bar G, is cast ot' metal in one piece, preferabl y oi' malleable iron, although any metal can be used, if desired, the cheeks B and B' being cast hollow, the hollow space a in each cheek conforming more or less to the general outline of the outside faces of each cheek, as desired, the shell part b being made thin, to secure a light block. By making these cheeks hollow they can be made full and thick from one outside face to the other, which admits of the edges ot' the blocks being made broad and round, while at the same time the block willbe made light and strong. The edges c of the blocks are cast or made round, as shown in cross-section in F1 gs. 6 and 7.

In casting the block, openings l and f, connecting with the hollow space, are left at the top and bottom of each cheek for the insertion of the iron straps G and G. Through these openings (l and f, in connection with an opening, g, in the inside faces of each cheek, the core can be sustained in order to cast the cheeks hollow in the usual manner of casting with a core. The straps Gr pass through their respective cheeks, and Ithe one Gr is formed by being doubled upon itself' before being inserted in the cheek, leaving an opening or eye, h, in its middle portion thereof, in which swings, vertically, a link, H. The hook J is riveted to and swivels in a block, K, which block turns on its journal l in a bearing in the upper end of cheek B', to which cheek it is riveted on the outside, as at m. The link H, by its free end, is arranged to pass over and embrace the end of the other journal, n, of block K, and in such position to serve as a bearingfor such journal. The end of the journal is bent or extends at right angles therefrom, forming the arm or lip o, which arm or lip 0, when the link is on the journal and the hook in its vertical position, lies across one side,p, of thcloop of the link, as shown in Fig. l more particularly, and prevents the accidental displacement of' the same and thereby the escape of the rope.

When desired to put the rope in the block, turn down the hook J into the position shown in dotted lines in Fig. 1,Which brings the IOO arm or lip o coincident with the opening q of the link. The link can then be swung over and away from its connection with itsjournal a, leaving the snatch or opening F free for the insertion of the rope. Reversing the operation secures the link to the journal and prevents the escape of the rope, as before stated.

Thejournal E ofthe pulley D passes through both cheeks and both straps, and the journal l through the cheek B and its strap G, so that with the link H hung to the strap G of the cheek B the iron straps practically take and receive all the strain upon the block when in use, thus relieving the cheeks from such strain, and enabling them to be made quite thin in their shell part, and necessarily securing a lighter block.

Making the cheeks of metal pulley-blocks hollow secures thick cheeks, and consequently broad edges, which, being rounded, as shown, prevent injury to the rope when the block is in use, and to the deck, 85e., if the block should fall thereon. Such results are very desirable, and especially so in metal blocks having two or more sheaves, as the intermediate cheeks also being made hollow secures such thickness and roundness of the edges without necessarily increasing the weight, as would be the result if solid cheeks were used.

The casting or making the cheeks of the block hollow, as described, is applicable to all kind of metal pulleyblocks, as well as to snatch-blocks, and the inside iron straps can be combined therewith, as is obvious.

The strap G can be solid instead oi' being folded, as described: but in such case provision must be made for hinging the link thereto.

The two cheeks ot' the block can be made or cast separately, and the cross-bar U connected thereto b v rivets, &c., but cast or made as described is preferable; and, again, the cheeks can be made hollow b v making each cheek in two parts or cup-shaped shells secured together at their edges by rivets or brazing; but it is preferable to cast the block as described.

Among the many advantages derived from a snatch-block constructed according to this invention may be mentioned the following: The arrangement and connection of the link with the block for the purpose described is simple, strong, and effective, is easily manipulated, and can be as well in thedark as in the light, and is not liable to get out of order. The inside iron straps sustain all the strain, allowing the block to be made light, and yet secure the thickness ofthe cheeks and rounded edges desired, all of which enables the block to be manufactured inuch cheaper and producing a snatchblock far superior to any now in use.

Having thus described my invention, what I claim, aud desire to secure by Letters Patent, is`

1. A snatch-block having its hook pivoted orjournaled to one cheek and a hinge linked to the other cheek, said link being adapted, by its free end, to pass over the end of and embrace thc other pivot or journal of said hook, and to be secured thereto by an arm or lip, o, of said journal, substantially as and for the purpose specitied.

2. A snatch or pulley block provided with the closed hollow cheeks B B', each consisting of a hollow cast metal shell formed with rounded edges c, substantially as herein described, the said cheeks being connected together by a cross-bar at their lower extremities, and the journals of the pulley-wheel being supported by the walls of the hollow cheeks, substantially in the manner specified.

3. The combination, with the two hollow cast-metal cheeks B B in a snatch or pulley block, of the two straps G G', inclosed within the hollow shells constituting the cheeks, substantially as described, the said straps being made with bearings for the journals ofthe pulley-wheel and extending out from the cheeks to connect with the hook, and each cheek being made in a single piece, for the purpose specified.

4. The combination, with the two hollow castmetal cheeks B B in a snatch-block, of the two straps G G', inclosed within the hollow shells constituting the cheeks, substantially as described, the strap G being extended out from one of the cheeks to form an eye for the hinged link, the strap G being formed to provide a hearing for one of the journals of the hook, and both of the said straps being made with bearings for the journals of the pulley-wheel, all substantially as set forth.

5. A cast-metal snatch or pulley block having its cheeks cast hollow, and having its hook pivoted or journaled to one cheek, and a. link hinged to the other cheek, said link being adapted, by its free end, to pass over the end of and embrace the other pivot or journal of said hook, and to be secured thereto by au arm or lip, o, ot" said journal, substantially as and for the purpose specified.

6. In combination with acast-metal snatchblock having its cheeks cast hollow, the wrought-iron inside straps, the hook J, pivoted or journaled to one cheek, and a link hinged to the other cheek, and adapted, by its free end, to pass over the end of and embrace the other pivot or journal of said hook, and to be secured thereto by an arm or lip of said journal, when all arranged substantially as and for the purpose specified.

In testimony whereof l have hereunto set my hand in the presence of two subscribing witnesses.

T. R. FERRALL.

Witnesses:

EDWIN W. BROWN, W. S. BELLows.

IOO

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