US87632A - Improvement in cutting threads on pipes - Google Patents

Description

,gisten @anni l im,

.IAMES'lVL CARPENTER, OF FLORENCE, .MASSACHUSETTS y Lette/rs Patent No. 87,632, dated March 9, 1869.

IMPRovnMnNT 1N currrurnnnnns 'olv Pipes, ecc.

The Schedule referred to in these Letters Patentanf making parl: of the sama.

I`o all whom it may concern.

Be it known that I, J Aims M. CARPENTER, of Florence, in the county of Hampshire, and State of Massachusetts, have made and invented certain new and usen ful Improvements in Machinery for Cutting Threads on Screws and the like; and I do hereby declare that the following is a full, clear, and exact description of the construction andoperatiou of the same, reference being had to' the annexed drawings, making apart 'of this specification, in which like letters mark like parts, and whereof- Figure 1 is an end, elevation, showing the segmental ,dies b b b", arranged on a single solid plate, a, such dies not being designed to open for withdrawal of the screw after the thread on the same is cut;

Figure 2, a side orv edge elevation of the same;

Figure 3, an end elevation, showing the oscillating' ring i surrounding the sliding head j, whereon are arranged the segmental dies g g g, designed to open for the withdrawal of the screw, after the thread thereon is cut;

Figure 4, a sideelevation oi'- the same, showing the bar m di Figure 5, a perspective view of a detached segmental er g Figure 6, anend elevation of ring i,

head j Figure 7, an end or face view of the sliding head j, whereon one segmental die, g, is in cuttingposition, one, y, is 'open or thrown back, as for removal of a screw, and all other parts detached; f

Figure 8, an elevation of the opposite end of head j, all other parts being detached;

Figure 9, an end elevation of q and l Figure 10, an end elevation of the holds ring i in place.

My invention has for its object the more easy and perfect threading of screws, pipes, and the like; and

It consists in combining, with a head or holder, four pieces, more' or less, of metal, vhaving threads upon their inner ends, by means of screws or pivots, insuch mahner that they may be turned on their centres for the purpose of obtaining an adjustment of theforward, or cutting-edges of the cutters, and alsoofeffecting, by the same movement, a clearance of the rear, or noncutting edges thereof.

detached from the stationaryl shell collar p, which l Heretofore sets 'of cutters composing a die have been used, airangedto slideradially in ways or grooves, for the purpose of opening the die, to release the screw, and they are efficient for this purpose. -Theyhave also been made with a curvature ofthe arc of a given circle, so that when slidden inward radially, to act on a bolt, of a circumference less than that circle, they would give a proportionate clearance, which increased as the cutter a proaclied the centre.

To enable ct ers skilled in the art to practise my l invention, i describe the same as follows:

In the accompanying drawings, the part marked a represents a single solid plate, to which are attached, by pivot-screws o o o, the segmental dies b bb, in the nature of equidistant radii, the outer ends of which are secured and controlled by screws d d', or wedges o o', in `combination with the projections e e' which form a part of plate a.

Having thussecured blank dies in a proper position, I proceed to tap out the same, and having previously made a continuous'stpaig'ht line, t, across the end and side of die and plate, that I may always determine the exact position of each segment when tapped out,I then loosen screws d or wedge o slightly, and tighten screw d or wedge fr correspondingly, thus moving the outer ends of dies b b l1" in the direction indicated by arrow 2, whereby it is obvious that the forward, or cutting-edge lr, of each segmental die, is moved toward the centre, y, of plate c, while the rear, ornon-cutting cutting and non-cutting edges of the dies should be very slight, i'or instance, the half oilia thousandth of an inch, or just enough to obtain what I term a clearance, whereby the friction incident to cutting screwthreads is greatly reduced:

If the threads in the dies become worn,` the edge o is easily sharpened by grinding-'faces d d' 4", and then the cutting-edge fr may be advanced by turning the die-lever on its centre for the l.purpose of adjusting it to its former position.

Segment b" is designed to represent a holder, the inner end of which is provided with a dovetail slot, wherein is arranged a removable die, c', and the die c may vary in length from pivot o, and in thickness of thread thus aiordingthe means of cutting large or small screws by simply changing the part 0.'.

My invention is designed to be used in connection with a Brown 8U Sharp77 screw-machine, or other similar machines, in which the blank, whereon a thread is to be cut, is made to revolve in a c chuck, while the thread-cutting dies have no revolving motion; but af# ter cutting a thread by the above-described device, the screw must be removed therefrom by a reverse motion of the chuck, which takes time, and often injures or destroys the thread. And to obviate these objections, I have made and invented an openingl-die or device, in which segmental diesg g g are" attached, by pivot 4screws o o o, to the sliding head j.

' Surrounding head j is an oscillating ring, i, provided with projections e o', 86e., through which pass the screws d d', 86e., whereby are held and controlled the outer ends of dies g g g", and these dies, held fast on head j, are tapped out, as above described, and their position, when so tapped out, may always be determined by theline t', marked against the straight sides thereof, on the face of head j.

The ring i, .tting shank le, is held in proximity to head j by the collar p, surrounding such shank, and whereon it is made fast by a commonfset-screwf edge s, recedes therefrom. But this variation of the thread. rection, bringing dies g g g again into cutting-posi;

g is a shell surrounding shank ic, and made fast in the screw-head, ,so called, of a screw-machine.

the distance which ring 'i shall be allowed to oscillate..

h is a handle for operating ring i.

While a screw is being threaded, the blank is made to revolve in a chuck, the thread.7 inthe die serving as a feed, and drawing thethread-cutting apparatus nearer such chlick, till the large screw Z, which rests on and slides along bar m, reaches notch n, when the ring i is oscillated in the direction indicated by arrow 1, whereby the dies g g' g are opened or thrown into position of die g', fig. 7, and the screw is then removed, without loss of time or injury o f Ring c' is now oscillated in the opposite dition. Shank It is slid back into shell q, and the process repeated.

In forming. opening segmental dies g g', 85o., the thread-cutting parts thereof must be less than a semicircle, and made wholly on one side ofa straight line, passing through the centres of head j,- and any pivotscrew o otherwise, it is obvious, such dies could not be opened.

I prefer three segmental dies, as herein shown, but one, two, or more, may be used.

The tooth of the openingdies, or-that part b'e- Y tween the screws l fl', should be made curved on opposite sides, and the ends of such screws, a little rounded,

, in shown, I consider one and the same in principle, and

all equallyof my invention.

I am aware that screw-threaders, having al portion of their` inner ends cut away, for clearance, have been swung on centres, and havebeen provided with means fol-adjustment on such centres. Such a threader, I do not claim; but having thus described the construction and operation of my improved device for cutting threads on screws and the like,

What I claim therein' as new, and desire to secure by'I-letters Patent, is

. 1. As my improvement of screw-threading dies, conjointly, the attachment of said dies, by pivots, to the die-stock, a series of longitudinally-concave cuttingthreads, of equal height throughout their entire length, and terminated at 'any angle to the curvature of said threads, in the plane of the straight-bevelled surface of the die-block, substantially as represented by iig. 4,

v and mechanism for adjusting said dies, to give clearance, and to retain them firmly in position when so adjusted, substantially as set forth.

2. Also, in combination with the dies, made and pivoted to the head-stock, as described, the oscillating ring and the adjusting set-screws, or their' equivalent, the wedges, substantially as described.

3. The notched arm m., in combina-tion with theshell q, ring i, and head j, substantially as and for the purpose described. y

JAMESM. CARPENTER.

Witnesses:

Rom. H. ALDRICH, A. PERRY PECK.

Images