US115291A - Luthee e - Google Patents

Description

I L. R. FAUGHT. \mprovment in DiGrStOCk for Cutting Screws.

N0,H5,2"9l-. Patented May 30,1871.

ATEN' FFICE.

LUTHER R FAUGHT, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN DIE-STOCKS FQR CUTTING SCREWS.

Specification forming part of Letters Patent N 0. 115,291, dated May 30,1871.

To" an whom it may concern: 1

Be it known that I, LUTHER R. FAUGHT, of

ii 1 thecity and county of Philadelphia, in the j State ofPennsylvania,have invented a certain f f new and usefulImprovement in Die-Stocks for Cutting Screws, of which the following is a specification: r i My invention relates to an improved method of arranging and adjusting the dies in the p stock so that the dies arev adjusted radially i 1 to the center of the bolt to be operated on, r and, when adjusted, each die will exert its cutting action upon the bolt in an advantageous manner and the operation of cutting a screw 1 :be performed with increased dispatch and ac- .Lcuracy; to which end my improvementconsists j A in the combination ofa fixed die, movable dies traversing in the stock and adjustable radially to thecenter of the bolt to be cut, sliding wedges to act upon the adjustable dies, and a screw to operate the wedges, as hereinafter more fully set forth. It is diflicult to attain accuracy of workman- 5 shipin cutting screws by the common diestocks or hand-plates as heretofore construct- Q .ed,the thread produced being imperfect and i the pitch irregular. The dies, moreover, owing r to their imperfect action upon the metal of the iscrew-blank, tend to squeeze or jam the same i instead of cutting it freely, and screws are frequently producedof varying diameters in dif I ferent portions of their length,rendering it extremely difficult to obtain a fit between the screw and nut. r necessarily inferior in strength to those which have a clean and true thread, and the cuttingdies become rapidly worn and require frequent Such screws, likewise, are

grinding. In the die-stocks embracing my improvements practice has demonstrated that these difficulties areovercome. easily and rapidly from their position and favor- .1 able action upon the screw-blank. Each thread of eachdie performs a cutting office, and,,by

The dies cut reason of their triangular bearing toward a common center, the strain upon them is equah ized. As there is notendency to jamor squeeze i the metalthe dies do not wear with the rapid] \ity of those heretofore used, The dies, moreover, having a narrow face, can be readily ground when worn.

I have found that the screws produced by my improved die-stocks have a clean, sharplydefined, and regularly-pitched thread, very nearly approximating to those out in a lathe and the operation is performed with a great saving of time and labor.

In the accompanying drawing, Figure l is a view, in elevation, of Whitworths die-stock, heretofore known and used, the cap-plate being removed to show its construction more clearly; Fig. 2, a longitudinal central section through the same; Fig. 3, a view, in elevation,

of a die-stock embracing my improvements,

with the cap-plate removed; and Fig. 4, a longitudinal central section of the same.

A suitable metallic plate or stock, A, provided with arms A A one. of which, A is made of sufficient length to be used as one of the handles by which it is turned, serves for the reception of the operating mechanism. A circular opening, a, is formed in the center of the plate, from which three guide-slots radiate at points equidistant from each other. Within these guide-slots are placed steel diesB B B that one, B, which corresponds in position with the longitudinal center-line of the die-stock being stationary, the other two being movable, and, from the radial position of the guide-slots, necessarily'adjustable to acommon center. The

dies B B are, respectively, moved toward the center of the opening a by two sliding wedges,

G O, which traverse in slots formed in the die- 1 stock A, and inclined at equal angles to its longitudinal center-line, their meeting-point being therein, and their greatest distance apart longnut, D, formed in the arm A of the stock A. The 'screw D is prolonged to such length as required, to be used in connection with the. arm A for turning the die-stock. A gage, c,

may be formed upon the stock A to indicate the proper positions of the dies and wedges for the diameters of the screws cut. The dies and wedges are maintained in the stock by a capplate, E, secured by screws e, and a smaller cap, F, is screwed to the stock near the meeting-point of the wedges B O to further guard against displacement thereof.

By comparing my improved die-stock with the \Vhitworth stock, shown in Figs. 1 and 2, its advantages will be more clearly apparent. In this form of die-stock the adjustable dies are not radial, and, from their form and position, cannot act with the ease and accuracy of mine. The stationary die serves chiefly as a guide or bearing in forming the thread, and only one cutting'edge at a time practically acts, thereby increasing the wear of the dies and the labor and time required for the operation.

The arrangement and operation of my dies, as hereinbefore shown, are such as to equalize the strain and Wear upon them. They exert equally a guiding and a cutting action, and are easily and quickly adjustable or removable, as circumstances may require.

I do not claim the use of radial dies in a screw-stock, as such have been heretofore known, but differently constructed and operated from mine.

What I claim as my invention is- 1. The combination of the stationary die, the movable dies adjustable radially relatively to the axis of the dies, and the adjusting-wedges moving endwise in the die-stock, all these parts being constructed to operate in combination, substantially as hereinbefore set forth.

2. The combination of the die-stock, the radially-adjustable dies, the adjusting-wedges,

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