US336687A

US336687A - Grab-hook for chains

Info

Publication number: US336687A
Authority: US
Publication date: 1886-02-23
Anticipated expiration: 1903-02-23

Description

(No Model.)

M. BARR.

GRAB HOOK FOR CHAINS.

I Patentgd Feb. 23, 1886.

WITNESSES UNITED STATES PATENT OFFICE.

MATHEW BARR, or AITKIN, MINNESOTA.

GRAB-HOOK Foe CHAINS.

SPECIPZCATION forming part of Letters Patent No. 336,687, dated February 23, 1886.

Application filed November 25, 1885. Serial No. 183,995. (No model.)

1"0 all whom it may concern..-

Be it known that I, MATHEW BARR, a citizen of the United States, residingat Aitkin, in the county of Aitkin and State of Minnesota, have invented certain new and useful Improvements in Grab-Hooks for Chains; and I do declare the following to be a full, clear, and eXact description ofthe invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

' This invention relates to grab hooks for chains; and the novelty consistsin the construction and adaptation of parts with aview to the service to be performed, as will be more particularly hereinafter set forth, and specifically pointed out in the claims.

Theinvention is designed as an improvement upon the device patented to M. Golgan, April 11, 1865, No. 47,241, and it seeks to overcome some of the defects of that device.

These hooks have been forged out of square bars of iron so arranged thatthe fiat sides will furnish a bearing for the links of the chain; but when thus formed the inclined sides of the two arms of the hook form a surface in which the link becomes wedged, and it frequently requires several blows from a hammer or other convenient device to break the connection. A still more serious fault, however, lies in the fact that the hook thus constructed is not durable. The hook in its service is subjected to great strain, and it requires a nice discrimination to give the proper strength and not have the hook bulky and unwieldly. When the hook is forged, the fiber of the metal is weakened by the act of bending it, and it is weakened at the very point where the greatest strength is requirednamely, at the junction of the two arms. Under the most favorable circumstances ahook thusforgedis barely ofsufficicntstrength at this junction to stand thenecessary tests of lumbering; but when, added to this weakening feature, the strain is brought against inclined faces, and all strain is directed to throw the arms away from each other, it results that the hook is frequently broken and is never capable of withstanding the severest strains. I seek not only to overcome the difficulties mentioned, but to greatly broaden the capacity of the hook to receive and resist greater strains.

I cast my hook of fine steel or malleable castiron of the proper form and capacity. Iavoid the wedging-surfaces, and I am enabled to readily re-enforce thejunction of the two arms of the hook by properly forming the molds at such points.

I do not rely for protection upon the fact that I cast the article instead of forging it.

The novelty of the invention resides in the features of advantage which the device enibodies, and these features I can more readily secure by casting the hook.

The invention is fully illustrated in the accompanying drawings, which form a part of this specification, and in which Figure l is a perspective view of my improved link-hook, showing the relation of the links in dottedlines. Fig. 2 is asection taken on the line x m of Fig. 1, and Fig. 3 a section taken on the line y y of Fig. 1.

I cast my book in the shape required for serv ice, thus leaving to the metal its full strength.

A designates the body of the hook, having eye a, and B designatesthe arm, the two being connected by the re-enforced junction 0. This junction 0 isthe part of the book which issubj ected to the greatest strain, and I re-enforce this part, not only for the purpose of increasing the resisting capacity of the hook, but also to provide a bearing, 0, for the link which is next to the one embraced by the arms A B.

b and b designate the bearing-faces upon the body A and arm 13, respectively, upon either side of the link-receiving slotD. These faces, as shown, have a slight incline; but they are substantially fiat, so far as any wedging effect from the link is concerned.

In Fig. 1 it will be noticed that, while the link 8 is embraced by the arms A B of the hook, the link 8 bears fairly upon the faces I) b and rests against the reeuforce G. The arm B is not only strengthened by the re-enforce, but the faces b I) prevent any wedging effect from the contact of thelink s. I thus not only strengthen the arm B, butIavoid any wrenching strain upon said arm.

My hook has alltheinherent strength of the metal and is adapted to resist great strain.

Vhile I have specified the preferable mode of manufacture-as by casting, it will be understood that a hook, if forged and having the flat bearing-faces b b and having the re-enforce O as a bearing for the 1inks,would possess some 5 of the advantages of my construction.

What I claim as new is- 1. A grab-hook for chains having approximately flat bearing-faces b b, to receive the link of the chain without wedging strain, and

10 having a re-enforce, C, as and for the purposes set forth.

2. A grab-hook for chains, consisting of the body A, arm 13, and re-enforced junction 0, the said parts A B having the flat faces I) b,

15 as set forth.

LIATHEWT BARR.

\Vitnesses:

SAML. S. LUTHER, FRANK E. SEAYEY.