US1958972A - Punching device - Google Patents

Description

May 15, 1934- J. M. MILLER v1,958,972

PUNCHING DEVICE Filed 0G13. 27, 1933 Patented May 15, 1934 UNITED STATES PATENT FFICE PUNCIIING DEVICE Application ctober 27,

9 Claims.

My invention relates to a punching device or tool adapted for use in power presses, foot presses, and the like.

Hereto-iore in the construction of ornamental T metallic rings or frames of scintillating appearance to similate a series of gems or as a substitute therefor a single punch mounted in a plunger was vertically reciprocated and thereby was produced an annular series oi burnished indentations in a circular blank resting in an annular groove in a lower die the blank being circularly moved towards the punch step by step by auxiliary mechanism engaging the blank, usually in contact with the lower face of the latter, which is specially roughened or indented to facilitate this interengagement.

Some of the disadvantages of the above con struction was the excessive time consumed in forming the cavities or indents one at a time; the 20. impossibility of locating the several cavities of the series in close adjacency to each other whereby the scintillating appearance was inadequate or entirely absent; and the rough or marred appearance of the bottom or back of thecompleted ring.

Certain objects of my invention are to overcome the above disadvantages by increasing the speed of indentation, by augmenting the scintillating brilliancy, and by avoiding defacement of the ring.

Further objects are to effect these ends in a structure adapted to facile change or substitution of the punches or of the hub, and to secure rigid retention of the punches.

Other objects and advantages, hereinafter adverted to, will be apparent to those skilled in the art.

To all the above indicated ends my invention consists in such parts and in such combinations of parts as fall within the scope of the appended claims.

In the accompanying drawing which forms a part of this specification,

Figure 1 is a side elevation, partially in vertical central section, of my novel device,

Figure 2, a section taken on line 2 2 of Figure 1,

Figure 3, a bottom plan view of the same,

Figure 4, a side elevation, partially in vertical central section, of a modified form of clamping member,

Figure 5, a side View, partly in central transverse section of the lower die of a press carrying a blank to be operated upon by the punching device,

1933, Serial No. 695,411

Figure 6, a plan view of a completed ring,

Figure 7, a section taken on line 7-7 of Figure 6, and

Figure 8, a bottom plan view of a modied form or" my punching device.

Like reference characters indicate like parts throughout the views.

In the construction illustrated 12 is a cylindrical head, centrally of which is an upright stern' 13 adapted to be detachably mounted in the plunger member of a press or the like. To the head is attached a pending cylindrical shank 15 including a downwardly tapering exterior lower portion, as at 16, and a flat lower face 17. The attaching means shown consists of a plurality of screws 18 supported in vertical openings 19 in the head, with their lower threaded portions 20 engaged in the threaded apertures 22 in the top of the shank. The attached head and shank constitute a hub and may be formed integral with each other, but the integral form does not possess all the advantages of the nonintegral construction. Centrally of the bottom of the head 12 is a cavity 24 provided with a thread 25, and the shank 15 is traversed by a central hole or bore 26 bounded by a wall 27.

A clamping member 28 enclosed by the hub comprises a transversely circular core or plug 29 provided with an axial bore 30, and a screw 32 including a shank 33 in the bore, a countersunk head 34 in the bottom of the core, and a thread 35 upon its upper portion engageable in the thread 25 of the cavity 24 of the head 12. There isa slot 36 in the head to accommodate a screw driver.

The core 24 has an external inward taper upwardly throughout its length leaving an annular lateral space 37 between its upper portion and an annular series of punches 39 whose body portions 40 are successively in contact with each other laterally, and project slightly below the lower faces of the core and the hub. Their upper ends abut against the lower face oi the head 12. The work contacting faces 41 upon the lower ends of the punch bodies are of any preferred shape, contour, ligure, or facet, but as herein shown are of rounded form. The shanks or bodies of the punches are transversely circular, but such sectional form is not exclusive.

The punches are tightly clamped against the wall 27 of the hub bore 26 by tightening the screw 32. The space 37 afforded by the taper of the core 29 makes possible the withdrawal of the core, after the screw is loosened, to enable substitution of punches when desired. For the purics poses of illustration the degree of taper of the core is somewhat exaggerated.

The screw 32 may be formed integral with the core 29, and in Figure 4 a modified form of clamping member 43 is shown so constructed.

The circular arrangement of the punches, as shown in Figure 3, is employed when the ring or frame to be operated upon is circular in shape, but when the latter is elliptical, angular, or of other shape the transverse sections of the hub shank and its enclosed clamping member must be of corresponding outline. When, for example, the ring or frame to be operated upon is rectangular, the clamping member 44 and the bore 45 of the hub shank will be transversely rectangular.

The use of my punching device is herein illustrated in conjunction with a rectangular die block 47 provided in its upper face with a circular groove 48 for the reception of an annular metallic blank 50. The die 47 is understood to be supported by the press table with the series of punches 39' in the vertical plane of the blank 50. The downward stroke of the punching device simultaneously impresses the blank with an annular series of cavities 51 so closely together that they are in peripheral communication with each other as shown in Figure 6, which contiguity ls required to secure a satisfactory scintillating eiect.

It will be observed from Figure 7 that the bottom or back of the blank 50 is smooth and undefaced. This is due to the fact that the simultaneous action of the plurality of punches makes unnecessary the use of means engaging the ring for rotating the latter step by step or otherwise.

The simultaneous action of the plurality of punches rather than the successive strokes of a single punch results in maximum speed.

The lateral contact of each successive punch with the next adjacent punch is vital to satisfactory scintillatory effect.

The shape, location, and method of attaching the clamping member insures a rm anchorage of the punches combined with facile withdrawal of the latter.

By reason of the attaching screws 18 it is possible to replace the shank 15 with Shanks having bores of other shaped transverse sections.

It is obvious that changes in details of construction within the spirit of my invention may be made. The description of the device has been given in detail merely for clearness of understanding, and no undue limitation should be understood therefrom.

I claim:-

1. In a punching tool, a hub provided with a vertical hole bounded by a lateral wall, a series of punches in successive lateral contact with the wall, and an exteriorly tapered. clamping member in the hole frictionally engaging the punches.

2. In a punching tool, a hub provided with a vertical hole bounded by a lateral wall, a series of punches in successive lateral contact with each other and with the wall, anda clamping member in the hole disposed concentrically of the series of punches and frictionally engaging the punches with its exterior face, said wall and face being disposed at an angle to each other in a vertical plane.

3. In a punching tool, a hub provided with a vertical hole bounded by a lateral wall, a series of punches in the hole in successive lateral contact with each other and with the wall, and a clamping member detachably engaging the hub in the hole and frictionally engaging the punches with its exterior face, said wall and face being in tapered relation to each other.

4. In a punching tool, a hub provided with a vertical hole bounded by a lateral wall and provided with a vertical cavity extending from the end of the hole and having a thread, a series of punches in successive lateral contact with each other and with the wall, a clamping member in the hole disposed concentrically of the punches and frictionally engaging the punches with'its exterior face, and a projection carried by said member provided with a thread engageable with the rst thread. i

5. In a punching tool, a hub provided with a vertical hole bounded by a lateral wall and provided with a threaded cavity extending from the end of the hole, a series of punches in successive lateral contact with each other and with the wall, and a clamping member comprising a core in the hole frictionally engaging the punches and provided with an axial bore, and a screw in the bore provided with a screw threaded portion engageable with the hub in the threaded cavity.

6. In a punching tool, a head provided centrally with a threaded cavity in its lower face, said head being provided also with vertical openings, a stem upon the top of the head, a depending shank abutting at its upper end against the head and provided with threaded apertures adapted to register with the openings, screws extending through the openings and provided with threads engaging in the apertures, said shank being provided centrally with a hole extending therethrough, and bounded by a lateral wall, a series of punches in successive lateral contact with each other, with the wall, and with the head, and a clamping member in the hole frictionally engaging the punches and having threaded engagement with the head in said cavity.

7. In a punching tool, a head portion, a shank portion having a central opening, and a punch 120 retainer portion attachable to said head portion and spaced from said shank portion to provide an opening for receiving a plurality of punches, said portions having cooperating parts for locking the punches in place upon attachment of said 125 retainer portion to said head portion.

8. In a punching tool, a head portion, a punch retainer portion attachable thereto and having an opening for receiving a plurality of punches, the walls of said opening being adapted to engage the punches for locking the punches in place upon attachment of said retainer portion to said head portion.

9. In a punching tool, a central element, a shank element spaced therefrom to provide an 135 elongated slot between the contiguous walls of the elements adapted to receive a plurality of adjacently positioned punches, one of saidwalls being tapered, and a head element secured to said rst mentioned elements, one of said elements being detachable from said head element, whereby the positioning of a plurality of adjacent pimches in said slot and the locking of the detachable element to said head element locks the i punches in said slot. 45

JOHN M. MILLER.

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