US1753181A - Fuse tongs - Google Patents

Description

April 1930. H. D. GRINNELL Q 1,753,181

FUSE TONGS Filed Sept. 26, 1928 7 Iuveniov: flaw; D. 'Gif'iW WZZ,

Patented Apr. 1, 1939 TTS ear FFIE HAROLD D. GRINNELL, 6F PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO THE C. A.

MANUFACTURING COMPANY, OF PITTSFIELI), MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS FUSE TONGS Application filed September 26, 1928. Serial No. 308,406.

This invention relates to hand tools and more patricularly to tongs for placing and removing cartridge fuses in cutout boxes, switches and other apparatus employed in electric circuits. The invention has for its object the provision of novel and improved means for manually performing these operations- W hile the invention is not restricted to the specific class of tools referred to, the pres ent embodiment thereof is especially designed to provide a suitable gripping medium whereby fuses of the cartridge type may be quickly and safely removed and replaced in their respective mountings without danger to the operator.

The invention will best be understood from a description of a specific useful embodiment thereof, illustrated in the accompanying drawings, wherein- Fig. 1 is a side elevation showing my device operatively assembled, the relative position therein of a removable cartridge being indicated in dotted lines;

Fig. 2, a similar view without the fuse, showing the relative positions of the gripping jaws and pusher when the aws are extended to their maximum spread, the handle being cut away;

Fig. 3, a view similar to Fig. 2, showing the relative positions of the same parts when the jaws are in the closed position;

F i, a top View on an enlarged scale of the tongs in an open position; and

Fig. 5, a perspective view, showing the device opera-tively applied to a removable cartridge fuse mounted in an approved type of switch.

in the present embodiment of my invention, I provide a pair of crossed arms 10, 11, pivoted together at an intermediate point 12 in their lengths, the upper ends being constructed to form opposing jaws 13, 14, and the lowerends being extended downward a convenient length to provide handles 15, 16, which are suitably shaped and apertured to be gripped by the fingers of one hand.

l l/Vhile the material of which my invention is constructed may be varied and adapted to the purpose intended, in the present instance I prefer to employ a hardened insulat on substance, such as pressed fibroid, which is suitably non-conductive and is alsosatisfactory fromjthe standpoints of weight and strength.

As illustrated in the accompanying drawing, the jaws 13, 14, when applied to the work or object engaged, are disposed in a plane transverse to the longitudinal axis of the object, the inner faces being preferably concaved to more readily accommodate objects of rounded outline, such, for example, as the fuse cartridge 17, while the free ends form inturned attenuated fingers 18, 19, presenting opposing transversely edged extremities for gripping the object.

Carried by and between the aws 13, 14 are two pairs of links 22, 23, of equal length pivoted together at their outer ends by suitable means such as the pin 21, the lower ends of each pair being similarly pivoted to one of the jaws at an intermediate or middle point in its length, the links of each pairbeing arranged on opposite faces of the supporting jaw. Suitable spacing means, such as the roller 20 which is mounted on the pin 21 between the outer ends of thelinks, and the washers 24 (Fig. 4) which are interposed between the lower ends of the outer pair of links and the corresponding aw faces, are employed tomaintain the links in parallel relationship. The spread of the jaws is limited by the links which are prevented from assuminga true alignment with each other and thus ing a locked position of the jaws, by the engagement of theroller 20 with the jaws at a predetermined point in its inward or downward movement which is calculated to prevent this condition.

. The outer or connected ends of the links 22, 23 collectively provide a third or supplementary jaw for engaging the work or object, the

links and their connection with the jaws being so proportioned and arranged that the point of contact in the bearing surface carried by the links is approximately at all times the same distance from the points of engagement of the jaws with the objectas these latter points are from each other. These work engaging points are thus disposed in the same plane and distributed at equal intervals about the circumference of the object, the resultant three iines of pressure converging toward a common center and effectually preventing displacement of the object inany direction.

As before stated, my invention is not in- 5 tended to be restricted to the precise form of embodiment herein shown and described, but variousmodifications in form, structure, combination and arrangement of parts are contemplated and may be made without departfing from the essential objects and principles involved.

I claim as my invention: 1. In a device of the character described, in combination, a pair of jaws for gripping an object and auxiliary gripping means carried on and operated by the jaws for moving the object into gripping position, said auxiliary means including: links pivotally connect-- edto each otherat one .end and at the opposite end to opposite jaws and having a bearing surface for contact with the object, the links and their connections with the jaws being so iroportioned and arranged that the bearing surface-carriedby he links is approximately all times the same distance from the points of engagement of the jaws with the object as the said points of engagement are from each other.

2. In a device of the class described, in com- 80 hina-tion, a pair of jaws for gripping rounded objects in a plane transverse to the longitudii'nilzaxis oi the object and auxiliary means carried on and'operated by the jaws for elevati-ng'the object into thegripping position, said means including arms pivotally connected to each other at their outer ends and to opposite jawsat their inner ends and having a bearing surface for providing a'third point of engagement with the object, each of said points of 40 engagement being approximately equi-distant imomthe others at vall times.

fiiittestimony whereof, I have signed my name to this specification. V

HAROLD D. GRINNELL.

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