US21950A

US21950A - Tackle-block

Info

Publication number: US21950A
Authority: US
Publication date: 1858-11-02
Anticipated expiration: 1875-11-02

Description

UNITED STATES PATENT OFFICE.l

JOHN FERRIER, OF CHARLESTOVVN, MASSACHUSETTS.

i TACKLE-BLOCK.

Specification of Letters Patent No. 21,950, dated November 2, 1858.

To all whom "it may concern:

Be it known that I, JOHN FERMER, of Charlestown, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Tackle- Blocks; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this speciicat-ion, in which- Figure l, is an elevation of my invention. Fig. 2, is a. transverse section of one of the blocks of ditto, taken in the line x, Fig. l.

Similar letters of reference indicate corresponding parts in the two figures.

This invention consists in constructing the block with two series or rows of pulleys, one placed above the other with the axis of one row at right angles to that of the other, the rope passing around t-he pulleys of the blocks as hereinafter shown and described, whereby a great number of pul- Vleys may be placed within a block of less cumbersome dimensions than usual, friction greatly diminished and a very eiiicient and powerful block obtained.

To enable those skilled in the art to fully understand and construct my invention I will proceed to describe it.

A, B, Figs. 1 and 2, represent the blocks. which may be constructed of wood or metal, and of rectangular form. In each block two sets or rows of pulleys C, D, are placed, the axis a, of one row being at right angles to the axis b, of the other and vone row being directly above the other. The two blocks are precisely similar in construction but they are so disposed relatively with each other that the row of pulleys C, of one block will be opposite to and consequently at right angles with the row D, of the other block, as shown clearly in Fig. l.

E, is the rope which passes around the pulleys of the two blocks as follows. The two ends of the rope are designated by o, (Z, and these ends pass over the two pulleys e, f, of the row C, of the upper block A, in opposite directions and then pass respectively around the pulleys g, L., z', j, le, and Z, my, n, o, 7), of the rows C, D, of the two blocks A, B, and then around the two remaining` rows, c', d, Fig. l, designating the parts that pass around the remaining rows from the rows previously described.

From the above description it will be seen that a large number of pulleys may be placed within a block of convenient form and the pull of the rope will be quite di-A rect. The block also will not be cumbersome as the usual blocks in which a plurality of pulleys are placed side by side, and the friction will be comparatively small. Larger blocks than usual may be made to operate practically well and a proportionate increase of power obtained for the reasons above stated.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, is

Placing two rows of pulleys C, D, in each block, the axis a., of one row being at right angles to the axis 7). of the other.` and the rope passed or adjusted around the pulleys as and for the purpose set forth.

JOI-IN FERRIER.

Witnesses:

GEO. I). KETTELL, JOI-1N M. SILvA.