US499822A - ceampney - Google Patents

Description

3 Sheets-Sheet 1.

Patented June 20, 1893.

n l U// (No Model.)

(No Model.) 3 sheets-sheet 2. G. I'. CHAMPNEY.

MACHINE FOR MAKING DIES.

Ely-fo,

(No Model.) a sheets-Sheen 3.

G. F. C'HAMPNBY.

MACHINE FOR MAKING DIES.

UNITED gSTATES.

PATENT OFFICE..

GEORGE F. CHAMPN'EY, OFTAUNTON, MASSACHUSETTS, ASSIGNOR OF THREE-FIFTHS TO ALFRED H. HARRISON, OF LONDON, ENGLAND.

MACHINE FOR MAKING DIES.

SPECIFICATION forming part 0f Letters Patent No. 499,822, dated J une 20, 1893.

Application filed December 4. 1889. Renewed .Tune 4, 1892. Serial No. 435,478. (No model.)

To all whom it may concern:

Be it known that I, GEORGE F. CHAMPNEY, a citizen of the United States, residing at Taunton, Bristol county, State of Massachusetts, have invented certain new and useful Improvements in Apparatus for Making Dies, fully described and represented 'in the following specification and the accompanying drawings, forming a part of the same.

My present invention relates to that process of making dies in which a die block is formed into a die by the impact of a patrice driven into it by ablow from a powerful hammer. In carrying out this process the die block, preferably of steel or iron faced with steel, is preferably first heated that it may more readily receive the patrice and is suitably protected during heating from the air so that oxidation is prevented. It is removed from the furnace at a high degree of heat, preferably a welding or white heat, placed under a hammer to which the patrice is attached and securely wedged inrplace, and the hammer is then caused to descend and drive the patrice into the die block. I have found that in practicing this process it isa matter of diiiiculty to properly'regulate the descent of the patrice into the die block. The patrice is likely to be driven too far in and thereby to become fixed in the die block so that it cannot be withdrawn without much labor and the possible destruction of the die. To meet this liabilityl propose to provide the patrice .with a laterally extended base, which base, by coming into contact with the top surface of the die block, arrests the movement of the patriceat the proper point and enables the patrice to be readily withdrawn from the die block, for instance, bythe mere insertion of a chisel between the abutting surfaces. Vith the patrice formed as last described I prefer to use a die block having its top face provided with a raised central portion. An advantage of this form of die block is that it permits the descending patrice to drive the air away from between its lower surface and the die block, from the center outward, preventing the inclosure of air between the approaching surfaces. This is an advantage because the effect of such inclosure of air would be to keep the metal of the die from following into the sharp angles and recesses of the patrice and tomore or less dull the impression and prevent the production of a sharply formed die.

' The die block with projecting surface is only a preferred-not an essential--form of die block, for use in connection with the patrice provided with a base as above stated. It is possible to use a die block with a Hat top in connection with such patrice.

In the drawings annexed to this specification and which form a part thereof and illustrate my invention-figure lis an elevation of a patrice representing the half of a machinists hammer in relief and Fig. la is a cross section of the same. Fig. 2 is an elevation of a die block having a projection from its top surface suitable for receiving an impression from the patrice shown in-Fig.

The die block is shown in this ligure as provided with a cap and inclosing casing, the

purpose of which will be hereinafter referred to. Fig. 3 is a cross section of the die block shown in Fig. 2, showing also the cap a.. Fig. Fig. 4. is a -side elevation and Fig. 5 a cross section of a patrice having upon it in relief the head of a fence picket. Figs. 6 and 7 are respectively a side elevation and cross section of a die block havinga projection shaped in the best manner tO receive an impression from the patrice shown in Figs. 4 and 5. Figs. 8 and 9 are respectively a side elevation and cross section of a die block having another form of projection. Fig. l0 shows in cross section a die block placed in position in a die holder and in elevation a hammer and guide pieces between which it works, by means of which the patrice may be forced into the die block. Fig. ll is a side view of the die holder, partly in section on the line ll-ll, Fig. lO. Fig. l2 represents on asmaller scale a drop hammer and frame suitable for use inpracticing my invention, showing a power windlass for raising the hammer, a trip for the latter, and a trip cord, by means of which the hammer may be released at any desired elevation, and allowed to drop.

I find it desirable that the projections on the die block should bear a certain relation to the form of the patrice, as shown in the figures. It will be seen that in each case the length of the projecting portion is about equal IOO to the length of the patrice and that the width of the projecting portion'is about equal to the greatest width of the patrice. he width of the upper surface of the projection will depend somewhat upon the mass of the patrice and will be wider where that mass is considerable than where it is small. Thus in the case of the hammer head the projection is made wider than in t-he case of the picket head. The height of the projection in the case'of the picket head is greater than in the case of the hammer head because the acute angles of the picket head are more diflicultto reproduce in the die than the more obtuse angles of the hammer head. I prefer also to leave a fiat Vmarginal space about the projecting portion of the die block, as shown in Figs. 2, 3, 6 and '7, as a stop is thus afforded for the flat base of the patrice and the dieisleft after impression in a more finished, regular form, requiring less trimming and planing, than would otherwise be the case. rlhe laterally extended base Z, of the patriceis indispensable in securing this result. Vere this absent, the patrice might be driven too far into the die block, necessitating much labor to plane or trim down the face of the die block to the proper level. It would also be exceedingly difficult to remove the patrice from the die block were it not for this action of the base of the patrice co-operatin g with the plane surface of the die block. The patrice having been driven bodily into the die block it would be necessary to cut away the top of the die block before the patrice could be removed. With my improved construction, however, it is only necessary to insert a chisel between the meeting surfaces of the patrice and die block and pry the two apart. fiat surface may, if preferred, be left on two sidesonly, instead of all sides, of the projecting portion. of thepatrice is to give the patrice solidityand prevent its being shattered by the force of the blow.

I do not limit Amyself to any particular apparatus with whichvto practice my invention. I have, however, shown in the drawings a form of apparatus suitable for the purpose, which I will now-describe.

The holder in which the dieblock is secured while beingY impressed, consists, as shown herein, of a solid block of steel d of suitable size, having planed therein a channel serving to receive the die block. Steel reinforcing strips c embracing the sides of the block are shrunk on and fastened by steel bolts f passing through the body ofthe block. Otherlarge bolts pass through the body of the block at in.

tervals of its length for the purpose of strengthening it against the tendency t0 split longitudinally undel'the stress of the blows of the hammer. The die block is held in position while beingimpressed by the tapering keys 7c tted into tapering key-ways formed in the block, and packing pieces t'. The hammer 0 is fitted to slide vertically between uprights The marginal A further function of the base' m n and carries a hammer block P to which the patrice is attached, preferably by cement, as shown by broken lines in Fig. l0. Two ratchet bars q q are attached to the two uprights respectively and two clutch es'B are pivoted upon the lateral face of the hammer and have on their lower ends teeth adapted to mesh with the ratchets. To the hammer is fixed a vertical mandrel d the ends of which are held by clips u u. About the mandrel is a catch E, cylindrical in form, as shown, the head E of which has init a hole through which the mandrel passes. The lower end of the catch E fits loosely. about a collar e free to slide up and down on the mandrel. About the mandrel is a'spring 0c held normally under a slight pressure between thehead of the catch and the collar. Near the top of the catch E and upon opposite sides are two eX- tcrnal lugs y y. Each of the clutches B is provided with a pair of arms B B. These arms B are so adjusted that when their upper ends rest against the outer surfaces of the lugs 1/ y as shown in broken lines in Fig. ll'the arms B support the collare and compress the spring Qc, and the teeth on tte lower ends of the clutches B are held out of engagement with ratchets q q; and so that when the catch E is depressed and the ends of the arms B are above the lugs ,t/ y the pressure of the spring acting through the collar U and the arms B will force the teeth on the lower ends of the clutches B outward into such a position that they may engage with the ratchets qq as shown in Fig. 11.

The operation of this device is as follows:- The clutches normally rest with their armsB against the outer surfaces of the lugs y in which position the teeth on their lower ends cannot engage with the teeth on theiratchets When the hammer descends and strikes the die-block the momentum ofthe catchE Acarries it downward against the pressure of the spring a: until the lugs y y release the IOO arms B and permit the clutches to spring outward under the pressure of the spri'ng to the position shown in full lines in Fig. 1l. The lugs y y are now caught under the upper ends of the arms B. The catch Eis thus held in its depressed position and the clutches continue to be forced outward and dragged along the teeth of the ratchets as the hammer rises on its rebound, until the hammer ceases to ascend, when the teeth of the clutches engage with the teeth of the ratchets and Ypreventa second descent. When the hammer .is again raised'the lower ends of the clutches B are pressed together by the operator. The catch E immediately returns to its normal place and locks the clutches B in their retracted positions. Handles D `maybe used for pressing the clutches together.

In practice the die block is first inclosed in the casing b c, preferably of refractory material, such as plumbago, so as to exclude the air, and is also provided with a close fitting metallic cap et, this provision for the exclusion of the air being made in order to prevent oxidation of the surface of the die block while hot. The die block isrthen .placed in a suitable furnace, is heated, preferably to a welding or white heat, is taken out of the furnace, the casing b c removed, the block placed in the die holder and securely wedged therein to prevent distortion of the die block under the stress of the blow of the hammer, the hammer carrying the patrice is raised, theclose titting rcap a is snatched off the die block, the hammer is tripped,falls, and drives the patrice into the die block.

The velocity with which the moving patrice strikes the die block may be varied according to the character of the Work performed. I find that the best results are obtained with a patrice moving at the rate of twenty-five or more feet per second, which is secured by giving the patrice a clear fall of ten feet and upward. For ordinary light work, such as making dies for ham mer heads, scissors, wrenches and similar articles, I find that the best results are secured by using a hammer weighing about one thousand pounds and giving it a drop of about fifteen feet. Vhile I mention these figures respecting the height from which the patrice may be dropped and the Weight of the hammer, I Wish it understood that I do not limit myself to any particular distance of drop or speed of patrice when striking the die block or Weight of hammer used in connection therewith.

In other pending applications, to Wit, Serial No. 332,533, led December 4, 1839, and

serial No. 333,357, filed December 11, 1839,'1 have claimed certain inventions herein disclosed and I do not therefore claim them here.

Having described my invention, What I claim, and desire to protect by Letters Patent, 1s-

1. The combination of a patrice having a base extended laterally on each side of the patrice, a die block having portions adapted to come into contact with the patrice base, and means for causing the patrice to move rapidly toward the die block and strike it while so moving. cutting the die at a single blow, the engaging portions of the die blockand patrice serving to arrest the movement of the patrice at the proper point, substantially as described.

2. The combination of a die block having a GEORGE F. CHAMPNEY.

Witnesses: K J. J. KENNEDY, EDWARD R. Woon'.

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