US390217A - Pulley-slock - Google Patents

Description

UNITED STATES PATENT QEETcE.

THOMAS R. FERRALL, OF BOSTON, MASSACHUSETTS.

PULLEY-BLOCK.

SPECIFICATION forming part of Letters Patent No. 390,217, dated October 2,1888. Application filed June 6, 1858. Serial No. 276,189. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS E. FERRALL, a citizen of the United States, and a resident of Boston, in the county of Suffolk and State of Massachusetts, have invented new and useful Improvements in Pulley-Blocks, of which the following, taken in connection with theaccon1- panying drawings, is a specification.

This invention relates to improvements in pnlley-blocks particularly adapted for use on gaffs on sailing-vessels in hoisting the peak, and it is carried out as follows, reference being had to the accompanying drawings, wherein- Figure 1 represents a front view, and Fig. 2representsarearview,of my improved block. Fig. 3 represents a central longitudinal section of the same; and Fig. at represents a side elevation of the improved blocks, showing them as applied for use on a gaff or spar.

Similar letters refer tosimilarparts wherever they occur on the different parts of the drawings.

a a represent the cheeks, and b I) represent the end pieces on a block, as usual, said parts being shown as made of wood; but they may be made of metal, if so desired, without departing from the essence of my invention.

a 0 represent metal straps on the insides of the cheeks a a, and d represents the spindle passing through perforations in said straps cc and in the cheeks (Ht, as is common in blocks. e is the sheave, journaled on the spindle (1 between the straps c c and checks at a, as shown in Fig,

The metal straps c a have downwardly-projecting extensions 0 0, preferably enlarged in the form of circular cheeks, between which is journaled on the screwbolt or spindlef the sheave g, which latter is preferably made smaller in diameter than the main sheave e, as shown in the drawings.

The secondary sheave g is preferably provided with a perforated or recessed sleeve-bearing,g,the perforations or recesses of which are adapted to contain the metaline or other suitable lubricant, g, as shown in Fig. 3. To enable the sheave g to be quickly removed from the metal-strap extensions 0 c in placing the loop h of the gaffrope around said sheave, as shown in Fig. 4, I pivot at i, on one of the metal-strap extensions 0', the not or screwthreaded plate i, (shown in Figs.2 and 3,) in the screw-threaded perforation of which is screwed the screw-threaded end of the bolt or spindle f, the opposite end of which is preferably madein the form ofa nicked head, f, as shown in Figs. 1 and 3, although, if so desired, it may be made as a polygonal head or as an eyebolt without departing from the spirit of my invention.

By having the screw-threaded plate or nut t pivoted or secured to one of the metal-strap extensions 0, I prevent said nut from working loose from the screw-bolt f, and I also prevent said nut from accidentally dropping off from said bolt or spindle or the strap-extension 0 while the operator is in the act of attaching or detaching the pulley to and from the looped rope h. (Shown in Fig. 4.)

H in Fig. 4 is the gaff or spar to which the looped rope h is secured, as shown, and k represent the rope leading from the sheaves e to pulley-blocks attached to the mast or other portion, according to the use to which the improved block is put. Heretofore blocks have been attached to gaffs or spars by means of hooks or eyes on the blocks connected to rings secured to the gaff or spar; but this is objectionable on account of such connection being too rigid and not having the proper flexibility for yielding to the movements of such gaff or spar.

By having the block provided with the sec ondary sheave g, journaled to the projecting ends of the metal straps c c and adapted to receive the looped gaff orspar rope h, such rigid connection is avoided, and the blocks are made automatically yielding and adjustable to the varying positions of such gaff or spar. Another advantage obtained in my improved construction of the bloekisconsiderable lightness as compared with the old style of blocks.

By having the strap-extcnsions c 0 made of circular form and wider than the straps c c said extensions serve the purpose of cheekpieces for the secondary pulley g, and thus prevent the chafing or wearing of the gaff or spar rope h, as shown.

The pulley-block, as shown and described, is adapted for use with two separate ropes, k and it, one for the main sheave and one for the secondary sheave, and for this purpose it is essential that there should be a divider between such sheaves, so as to prevent said ropes from getting in contact with each other, and I therefore employ the lower end piece, b, as described, which is secured to the cheeks a a between the main and secondary sheaves, as shown in Fig. 3.

Having thus fully described the nature,construction, and operation of my invention, I wish to secure by Letters Patent and claim- 1. The herein-described pulley-block, con sisting of the cheeks a a, the main sheave e, and its pin d, combined with the metal straps c 0, having outwardly-projecting parts 0 c',the pin or bolt f, secured to the latter, and the secondary sheave g,journaled on said pin or bolt, and the stationary end piece, I), secured to the cheeks a a between the main and secondary sheaves, as and for the purpose set forth.

2. The cheeksaa, the pind, and main sheave e, journaled on said pin, and the metal straps c c,having the outwardly-projecting parts 0 c, as described, combined with thescrew-threaded bolt f, the secondary sheave g, journaled on said bolt, and the screw-threaded nut or plate adapted to receive the screw-threaded end of the bolt f, and pivoted or riveted to one of the metalstrap extensions 0, substantially as and for the purpose specified.

3. In a pulley-block, the main sheave e, journaled on the spindle d,and the metal straps c 0, having outwardlyprojecting parts 0 0, combined with a secondary sheave, g, journaled on a pin or bolt passing through such extensions 0 c, and the stationary end piece, I), secured to the checks at a between the main and secondary sheaves, substantially as and for the purpose set forth.

4:- The cheeks a a and the main sheave e, journaled on the pin (1 in said cheeks, combined with the metal straps c 0, having the enlarged ends 0 0, adapted to receive the pin or bolt f, and the end piece, b, secured to the cheeks a a between the main and secondary sheaves, and to serve as checks for the secondary sheave g, journaled on said pin or bolt f, substantially in a manner and for the purpose set forth.

5. Theimproved pulley-block, as described, having main sheave journaled on a pin in the block-body,combined with a secondary sheave journaled on a pin or bolt secured to outwardly-projecting parts of metal straps of the main portion of the block, and the end piece, 11, secured to the cheeks a a between the main and secondary sheaves, substantially as and for the purpose set forth.

6. In a p11lley-block,ainain sheave arranged Within the block-body and a secondary sheave arranged outside of the same, and the end piece, I), secured to the main and secondary sheaves, combined with metal straps having perforations for receiving the pins or bolts of the respective sheaves in the block-body and outside of the same, respectively, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, on this 5th day ofJune, A. D. 1888.

THOMAS R. FERRALL.

Witnesses:

ALBAN ANDREN, HERBERT LOND.

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