USRE2520E - Ira merritt - Google Patents

Description

,'niteh tstss @anni @fitte IRApMERRlTT, 0F ,ABINGTON MASSACHUSETTS, ASSIGNEE BY MESNE ASSIGNMENTS 4Oli HIMSELF.k

Lettera Patent'No. 24,354. dated June 7, 1859 reissue No. 2,520, dated March 19, 1867.

IMPROVEMENT IN KNIVES.

To ALL'wHoM rr MAY conocen: y

Be it known that I, IRA MERBITT, of Abington, in the county of Plymouth, and State of Massachusetts, have invented a new and improved Extensible-Blade Knife, more particularly adapted to the use of boot and shoemakers,of which the following is a'full, clear, and exact description, reference being had to vthe accompunying drawings making part of this specication.

The invention provides for inserting the whole or a considerable part of the blade within the handle or stock i in sich a manner tha-t while it is held firmly 'in anydesired position for cutting, it may be extended out froth the handle when necessary o1' as the blade wears away.' Persons engaged in cutting out stock in boot and shoe manufactories, and the .shoemukers themselves, find a great inconvenience from the rapid wearing away of the cutting knife which they employ, as the nature of the stock on which they operate requires afrequent sharpening of the knife, so that no sooner has the operative become accustomed to a blade of a certain length than he finds it wearing away underhis use, soon requiring to be replaced by another of considerably greater length than lthe one he has just resigned. These frequent changes interferematerially with the neat and accurate manipulation which van artisan acquires by the continued use of a tool to which his band has become accustomed. The object of my present invention is to obviate this diiliculty, and to produce a knife for the above* and-similar purposes, thev v blade etwhich, as it is worn "way by usenniay be drawn ont further from the handle, and thus be kept atl such s:

uniform length us inay suit the convenience of the person using it, and in which the hladewherr-wern away may be easily replacedl by another of a similar form, or by one of adifferent form suited to different kinds of work.. This knife consists of a hollnwhandle or blade holder provided with clamps or nippers for grasping and holding the blade firmly in any desired position, and also of a blade which may be drawn out more or less from th'e handle and rmly held in ditferent positions as the blade wears down, or to suit the requirementsof the person using the tool. i

Figure 1 is a. view of thc knife with the blade 'partially extended.

Figure 2,y a longitudinal section through thc saine.

Figure 3, -detail to be referred to hereafter.

In the said drawings A is a handle of wood in which is inserted longitudinally a. metal tube, ai, one end of which may have cut round its outer surface a groove, -'c in which tit pins d, passing through the edge of a metal nut, B, on the end of the handle, and holding the nut in place but permttingitto be turned round freely in either direction. Within the tube a is placed a long bifuroated rod of meta-l, D, the bifurcation e extending nearly the whole of its length to receive the blade the two parts of the rod thus forming a pair of clamps or nippers. This clamp-rod,l D, hasforlned on its upper end a scrcw,f, which engages with the nut B, so that by turning the nut in one direction the piece D is thrust `out further from the opposite end of the tube a, while by turning the nut in the other direction tho piece is retracted. rlhe end of the piece D opposite to the screw, or that whichmay be termed the lower or outer end, is somewhat enlarged, forming a bulb, g, made of'such n diameter that when the blade is inserted in the slit e, the jaws 1 and 2 of the nippers shall be somewhat wider than the bore of the tube a. If now the piece D he retracted by turning the nut B, the inclined faces of the bulb q will be drawn against the edge of the tube a, and the nippers will be pressed tightly on the blade, securing it rmly in any position the operator may wish. i; Ady requires that the nut be turned in the opposite direction to release the blade,

Awhen it can either be drawn out further from the handle or be removed to be replaced by another; or, itrcquired,

the blade may be pushed back into the handle occupying the slit e, when the jaws l and 2 may be closed over its point, andthe knife can be safely carried about the person. The blade is to be formed generally of a piece of steel 0f even or about even width, and tempered the whole or nearly the whole of its length, so that it may be adjusted and held in diifercnt positions inV the handle, and so that portions which serve at one time as the tang of the blade may, as the blade wears away, become the cutting part. It may have its opposite edges ground down to or approximating to a cutting edge, or one edge alone may he ground down or sharpened, or the blade may be of unifor .1 thickness entirely across it, and have a spear point formed upon it as seen at iig. 1. For some kinds of V work a blade shaped ns shown in iig. 3 may he preferred. it will readily be .seen that such a blade may bev adapted to the snnie handle, the portion, h, or tangpf the knife being made to fit in the slit e, and this part muy be so formed, if required, that when the broad port, l, of the blade has beengvorn away the tong portion itself may be convertedsinto a blade simile-r to the blade C, bymerely breaking oli the portion Zat the shoulder 5.

I claim tho knife handle heifen descvibed pi'ovidedwith means for clamping the blade, and for allowing the cutting edge or pont'to be adjusted with respect to the handle substantially as set forth.

I also claim adjustable blades so made ns to be xell and held in different positions in the handle7 subston, tinlly as set forth.

IRA MERRITT. Witnesses:

SYLvANUs NASH, SYLvANUs McKENNEY.

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