US1077993A - Tackle-block. - Google Patents

Description

J. T. McM-ILLAN.

TACKLE BLOOK.

' APPLICATION IILED MAY 24, 1913. I 1,077,993, Patented Nov. 11, 1913.

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JAMES T. MelYJLILTiAN, or nnrnorr, MICHIGAN.

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To all whom it may concern:

' Be it known that I, "JAMES T; MOMILLAN,

a citizen 'of the United States, residing at,

Detroit, county of lV-ayne, .State of Michigan, have invented a certain new and useful Improvement in Tackle-Blocl'rs, and declare the following to be a full, clear, and exact description of the same, such as willenable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

This invention relates to tackle blocks and has for its object a tackle block that can be lifted, while free of weight, Without tipping over or twisting the lines soas to become tangled. It is especially adapted for the lowering of life boats from passenger boats.

The figure is a perspective of the tackleblock and the rope running thereover.

A block or casing a is provided with two slots Z) on either side, through which protrude portions of the two pulleys or sheaves c, that are ournaled in the block. One, two, three or any number of sheaves may be used, and any style of block. A lifting hook d is located at the lower end of the block. This is the usual construction of a tackle-block.

Onthe large passenger boats, the lifeboats are very often carried in groups of either two or more. The davits (not shown( support the ropes and tackle-block and the two tackle-blocks are always kept hooked on to one life boat. One or more life boats are located on the deck behind or under the life boat to which the blocks are always kept at tached. In case of accident, the davits are turned around and the first life boat is let down with little difliculty. The trouble has been in hauling tackle-blocks backup to get the next life boat. Great difficulty has been experienced in drawing the tackle blocks up on account of their tendency to tip over or turn on the lines and twist them so as to tangle the rope and prevent a quick hauling of the tackle-blocks back up for attachment to a second life boat. Heretofore it has been sought to remedy this defect by carrying a comparatively heavy weight on the bottom of the tackle block above the hook, but this does not prevent the tackle block from twisting the rope. The problem has also been sought to be solved by employing a three-sheave tackle block and using a central sheave that is journaled in the block specification of Letters Patent.

. higher up than the sheaves on either side.

This to a certain extent'hashad a tendency to prevent the tipping of the block. H'ovw ever, this form of construction requires the use of a three sheave-block and hence multiplies the lines to six. Avery great objection to it is that it is an iexpensive form ofconstruc'tion, more than doubling the cost of the tackle-block. 1 x

I prevent the tipping of the block and reduce the liability of the twisting of the ropes by employing guides for the ropes that are somewhat spaced from the tackleblock. These guides are rigidly attached to the tackle-block and may be made in almost any form. The form that I have adopted has a pair of bars 6 each of which is screwed to the side of the tackle-block, extends substantially as far beyond the tackle-block as the tackle block is long, then arches over the top .of the block. The bar then returns parallel with the first mentioned portion and is screwed to the same side of the block. There are two of these bars and they are shown each with two eyes, 9, as guides, although the bars and guide holes may be varied as the number of lines varies. The idea is to have a rigid guide which guides the rope at a somewhat spaced point from the tackle block, so that the guide may resist any tendency of the block to tip and may also considerably reduce the tendency of the block to revolve and twist the ropes.

I am aware that guides for ropes in connection with pulley-blocks are not broadly new. Pivoted arms have been used to guide a rope over a sheave for a clothes-line and for an awning-pulley, but these pulleyblocks were never intended for the use for which my tackle-block is designed, nor are they adapted for such use. It requires the guides tobe supported rigidly on the tackleblock, so as to be in a fixed relation therewith, to prevent the tipping of the tackle block and reduce the liability of twisting. I am also informed that sheathings have been employed over tackle-blocks and the sheaves. These sheathings have had guides which contact the rope for guiding it into the groove of the sheave, but these guides have not been sufiiciently spaced from the tackle-block to accomplish the objects that I have in view. They would not absolutely prevent the tipping of theblock and they wvould have little or no tendency to reduce Patented Nov. '11, 1913. Application filed May 24, 1913. Serial No. 769,577.

the twisting liability. vl/Vhat is inoreithey are somewhat expensive and hard to assemble. What I- claim is 1. The combination with a tackle-block, provided with one or more sheaves; of a guide for each line passing over the tackle block, the guide being attached to the tackleblock and held in fixed relation therewith, each guidebeing suflioiently spaced from the block to exert a guiding influence upon the line at a somewhat spaced point from the tackleblock so as toresist the tendency of the block to tip over and to reduce the lia bility of the block to twist the lines, substantially as described.

2. Thecombination of a tackle-block pro- Gopies of this patent may be obtained for vided with'one or more sheaves, of a bar for each line passing over the tackle-block such point with a guiding eye through which the line passes, whereby the tendency of the block to tip is resisted by the guides and the liability of twisting the lines is considerably reduced, substantially as described.

In testimony whereof, I sign this specification in the presence of two witnesses.

JAMES T. McMILLAN. Witnesses:

AGNES M. HIPKINS, VIRGINIA C. SPRATT.

five cents each, by addressing the Commissioner of latents, Washington, D. C.

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