US2527091A

US2527091A - Punching and die mechanism for the production of mica washers

Info

Publication number: US2527091A
Application number: US5778A
Authority: US
Inventors: Jr Ralph A Carrier; Dreyfus C Davis
Original assignee: ASHEVILLE MICA Co
Current assignee: ASHEVILLE MICA Co
Priority date: 1948-02-02
Filing date: 1948-02-02
Publication date: 1950-10-24
Anticipated expiration: 1967-10-24

Description

Oct. 24, 1950 R. A. CARRIER, JR., r-:rAL 2,527,091

PUNCHING AND DIE MECHANISM FOR THE PRODUCTION 0F MICA WASHERS l Filed Feb. 2, 1948 3 Sheets-Sheet 2 V BY C- 24, 1950 R. A.YcARR|ER, JR., Erm. 2,527,091

PUNcHmG AND DIE uEcHANIsu Fon 'ma PRODUCTION oF MICA wAsmsRs Filed' Feb. 2, 1948 3 Sheets-Sheet 3 Ralph A. Carr/er, Jr.

Dreyfus 6. Dov/fsr JNVENToRs BY @um Patented Oct. 24, 1.950

PUNCHING AND DIE MECHANSM Fon Tini PRODUCTION or MICA wAsHERs Ralph A. Carrier, Jr., Getton, and Dreyfus C.

Davis, OteeIi, N.

C., assignors td Asheville Mica Company, Asheville, N. C., a corporation Application February 2, 1948, Serial No. 5,775

Claims.

This invention relates to punch and die mechanisms operable in conjunction with a punching press and it has more particular reference'to mechanisms of this type used for producing mica washers. It is the general object of the invention to provide a punch and die mechanism by means of which an increased production of washers may be obtained and by means of which the same mechanism with small changes is adapted to produce washers of a large variety of sizes and with all diameters of the central hole.

A main object of the invention consists in providing means whereby adaptation of the same mechanism for diierent sizes may be obtained by making a very small number of parts exchangeable and by providing means for making these parts easily removable.

A further object of the invention consists in providing means whereby multiple cutting can take place, with a large variety of diameters of the washers and of the central holes.

A further and more specic object of the invention consists in providing means whereby, with one die of a given size, washers with a large variety of inside diameters may be cut.

A further and more specic object of thek in-r vention consists in providing a die in which the blanking punches as well as the piercing punches may be readily replaced by other punches of different size.

A still further and more specic object of the invention consists in providing a guard or pro' tective device surrounding the movable parts so closely that the operator may bring his hand safely into proximity tothe reciprocating parts of the machine, while placing the work sheet in position. This allows a largely increased production and the production of washers from smaller and less expensive mica sheets.

Further objects will be made apparent in the course of the following detailed description of the invention.

The inventive concept is capable ofbeing embodied into different constructions, but in the drawing only one such construction is shown by way of example. It is to be understood that this example has been selected in order to explain the principle of the invention `and the best mode of applying such principle, but does not supply a survey of further possible modes of application. Modifications of the example shown do therefore not necessarily constitute a departure from the invention.

In the accompanying drawings:

Figure 1 is an elevational view of a punch and die mechanism.

Figure 2 is a plan view of the mechanism, with the punch holder removed.

Figure 3 is an elevational sectional view of the mechanism, the section being taken along line 3-3 of Figure 1.

Figure 4 is a sectional plan View, the section being taken along line 4-4 of Figure '1.

Figure 5 is another sectional plan View the section being taken along line 5-5 oi Figure 1.

Figure 6 is another plan View which is however taken by looking upwardly from line 6--5 of Figure 1 towards the die assembly.

Figure 'l is an exploded perspective view of the matrix die carrying base and of the matrix dies.

Figure 8 is an exploded perspective view of the parts connected with the upper die assembly.

The punch and die mechanism according to the invention may be associated with the standard mechanism operated with a standard press; only those parts of the known mechanisms are shown which are closely associated with the improvements according to the invention. In all other respects it is assumed that the mechanism shown is connected with the usual type of standard punch presses, and is operated in the well known manner.

In Figures 1 and 3, I0 indicates the stem of a punch holder Il which is adapted to be clamped into the ram of a punch press moving up and down or in any other direction, the vertical direction being selected for a more convenientf showing. The punch holder ll may be of any approved construction and is movable by means of slide blocks ,l2 along the columns or spindles i4 which are mounted on the die shoe I6.

On said die shoe a split die base indicated generally at I8 is mounted consisting of the two members I9, 20 which are held on the die shoe by means of screws 29 and dowels 2l. The die base I8 as a whole may be of substantially circular shape. The two halves I9, 20 are semicircular and face eachother along parallel surfaces 23 across a gap. A number of substantially semi-circular notches or recesses 22 are provided `in the two parallel surfaces which accommodate the lower portion of the blanking punches 24.

a grooved or restricted portion 21. They are provided with a central cylindrical bore or hole i 28, which is substantially of the diameter of the piercing punches 30, near the cutting edges, but

is widened in the remaining portion of the blanking punches to allow the disks cut out from the center of the washer to drop. Bores 3| in the die shoe are arranged which correspond with the bores 28 and form discharge channels for the said centers.

The blanking punches are held rmly within the notches or recesses 22, the lower portion of which accommodates and holds the widened foot portion 26. The two members I 9 and 20 which are encircling the punches are held in their relative position by means of clamping screws 33, shown in Figures and 7 and passing between the notches or recesses and the punches at the height of the grooved portions 21 of the latter. Bores 34 for the passage of these clamping screws areshown in Figures 5and7.

The split die base holding the punches and the die shoe, as will be seen from the above, are so rmly held together that they form a structural unit.

Above the split die base a live rubber plate or ring is' located, upon whichv the' stripper plate 36 rests. The stripper plate may be circular with cylindrical holes or bores 31 closely surrounding the upper Vportion of the blanking punches 24 carrying the cutting edges. The upper surface of the stripping plate may be located slightly above the end faces of the blanking punches 24, as is customary with arrangements of this type.

The female portion of the die is firmly held in the punch holder Il byV means of screws and dowels which are however not shown in Figure 3 of the drawing for the sake of clarity. It comprisesV the die member 40 (Figure 8) which is of circular shape and is provided with an elongated recess 42 along one of its diameters, in its upper portion.v The lower portion facing the die base or male die assembly is provided with the bores or openings 44 leading from the recess 42 to the outer (lower) surface ofthe die member where they cooperate with the cutting edges of the male punches 24.' Thenumber of bores 44 is equal to the number of punches used,

and these bores accommodate the knock out cylinders 45 of the ejector or shedde'r'mechanism of the die assembly. These cylinders arev provided with central bores 46 through' which the piercing punches 3U are'passing. The piercing punches 30 comprise an active'or'punching portion held by a stem 48 whichV is xedly mounted on a piercing' punch plate 50. The punch plate is interchangeable so as to bring piercing punches of different sizes into action. l

Behind the piercing punch plate 50 a backing plate 52is arranged for transmitting the p'ressure to the assembly and for taking up theA forces produced by the shearing resistance of the material.

The backing plate 52 and"the piercing punch plate 50 are both provided with aligned

additional bores

54, 55 respectively, arranged in the latter plate around the piercing punches. Through these bores knock out pins 55 are passing, which press on an elongated knock out plate 6B resting on the upper surface of the knock out cylinders 45 and provided with bores 6l. These pins on the other end, which is located above the backing plate 52, are acted up'on by an elongated pressure equalizer plate 62 which may move within an elongated' recess 64 of the punch holder l l. The equalizer plate 62 is'rnoved within the recess 64 by the knock out rod 65'held by standard die presses.

Closely surrounding the entire female die assembly and ejector is a guard member 'l0 (Figures 1 and 2) which extends upwardly up to the press stock and on the other side reaches down so far that only a small slot 'l2 is left between it and the plane passing through the upper surface of the stripper plate 36. The guard plate may be provided with slits o1' windows 14 permitting observation of the punching process; but otherwise the slot 'l2 is so small that merely the stock or work piece may be inserted. The

guard plate is supported by posts 15 (Figures 2 and 6) which are supported in the die shoe. The operator is thus fully protected even if working in the immediate vicinity of the press. The close surrounding of the die permits a close approach of the operator who may use his hands safely at a very short distance from the tools. In an arrangement of this type this leads to a greatly improved production and economy, as on account of certain irregularities of the sheet it is frequently necessary to place work sheets in certain positions to be selected individually to obtain good results. Sheets with defects or irregularities have therefore no longer to be discarded.

The operation of the mechanism need not be describedY in detail. It may only be mentioned that upon movement of the press head the female die assembly mounted on the punch holder is moved against the male die member assembly with the piercing punches 30 entering the bores 28 and the blanking punches 24 cooperating with the cutting edges of the die member 40 to form the blank. The stripping plate 36 is pressed down and the rubber is compressed so that the blanking punches to a certain extent may enter into the bores of the female die member 40 thus severing the blanks from the stock. Upon return movement of the press-head, the rubber expands the stripper plate and pushes the inner sheet from which the washer disks have been removed upwardly. The blanks are still held on the upper part of the cutting portion of the piercing punch. The knock out mechanism is now Working with the knock out rod pressing down on the equalizer plate and the knock out pins 55 pressing against the knock out plate 60. The plate presses the knock out cylinder downwardly so asto eject or remove the washers from the piercing punches.

.The mainvadv-antages of the construction, as above described, consist in the fact that the blanking and piercing punches are both readily removed without dificulty, the former by disconnecting the members of the split base I8 and the latter by removing the interchangeable punch plate 50. Washers of any size'and any central bore may thus be made on the same punch and die mechanism on which merely certain parts are exchanged. It is possible, if merely the diameter ofthe central hole varies'fto continue operation after exchangingl the punches-in the manner indicated in Figure 7, an operation which is easy to perform within a short time. Moreover the construction embodies a -multiple cutter which greatly increases the output. A main advantage also resides in the above-explained guard plate providing full'protection to the operator without forcing him to keep ata distance from the tool. The press operator can therefore safely position smaller and cheaper or partly' defective sheets of mica on the die for high speed operation.

The production is increased both on' account of the multiple die "and on account ofthe .closeness ofthe operator4 to the tool. v

. It will be clear that. constructive changes or variationsof an unessential'characterido not affect the invention.

. Having described the invention, what is claimed as new is:

1. A punch and die mechanism for punching washers and similar articles comprising a reciprocable punch holder, a female die assembly held thereby, said assembly including a plurality of exchangeable die members, eachv provided with a piercing punch and an ejector mechanism, a die bed, a male die assembly, including a plurality of exchangeable vmale blanking punches and a split die base for holding said blanking punches, said die base consisting of a plurality of members, holding said punches pressed against said bed in operative parallel position when joined together and a stripping plate surrounding the ends of said blanking punches.

2. A punch and die mechanism for punching washers and similar articles comprising a reciprocable punch holder, a female die assembly held thereby, said assembly including a plurality of exchangeable die members, each provided with a piercing punch, an ejector mechanism, a xed die shoe, a split die base consisting of two members facing each other across a gap both adapted to be fixed on said die shoe, said members being provided with a plurality of aligned recesses on the sides facing each other, a plurality of removable blanking punches adapted to be placed into and to be held within the recesses of the two members facing each other and enclosing the lower part of said removable blanking punches, while the upper part of said punches project upwardly, therefrom and a stripping plate surrounding the projecting ends of said blanking dies.

3. A punch and die mechanism for punching washers and similar articles comprising a recprocable punch holder, a female die assembly held thereby, said assembly including a plurality of exchangeable die members, each provided with a piercing punch and an ejector mechanism, a xed die shoe, a split die base, consisting of at least two base members xedly but removably connected with said die shoe, said members having surfaces facing each other across a gap, and being provided on the surfaces facing each other with a plurality of cylindrical recesses, facing each other, adjustable clamping means for holding said base member at a predetermined distance, removable cylindrical blanking punches with cutting edges having enlarged foot portions, adapted to t into the space between the cylindrical recesses of the two members facing each other, and to be xedly held therein along a part of their length with their end portions carrying the cutting edges projecting from the die base towards the female die assembly, and a stripping plate and a rubber base plate surrounding said projecting ends of the blanking punches.

4. A punching press with a punch and die mechanism for punching washers and similar articles, comprising a stationary male die assembly, holding a plurality of blanking punches, said assembly including a die shoe, a split die base, consisting of at least two base members Xedly but removably connected with said die shoe and with each other, said base members having surfaces facing each other across a gap, said surfaces being provided with cylindrical recesses adapted to fixedly hold said exchangeable blanking punches, each blanking punch being provided with a central hole, a reciprocating punch holder, adapted to carry an exchangeable female die assembly provided with a recess of a length substantially of the length ofthe exchangeable die assembly, the said die assembly including an exchangeable die member provided with a plurality of bores equally numbered to the number of blanking punches and cooperating with the blanking punches of the male member, said die member being further provided with an elongated recess above saidbores, a plurality of knock-out cylinders, each provided with a central bore, located in the bores of the die member, an elongated knock-out plate, arranged within the recess of the die member and pressing against said cylinders, a piercing punch plate and a backing plate provided vwith holes, the holes in said plates being aligned, the die member, backing plate and piercing punch plate being held against each other and being removably xed on the punch holder covering the recess in the same, piercing punches held by and projecting from the Ipiercing punchpl-ate through the recess of the die member and through the central bores of the knock-out member, knock-out pins acting on said knock-out plate passing through the aligned holes of the piercing punch plate and the backing plate, an equalizer plate arranged in the recess of the punch holder behindthe backing plate and a knock-out rod, held in said punch holder and operated by the press.

5. In a punch and die mechanism the improvement comprising: a split die base including a pair of members removably mounted on the die shoe of the mechanism, a plurality of notches in each of the members of the split die base, a plurality of exchangeable blanking punches mounted in said notches of said die base, and means for holding said blanking punches from vertical displacement.

6. The combination of claim 5 in which one of said members has one side in juxtaposition to one side of the other of said members, and said notches being substantially semi-cylindrical and positioned along each of said sides forming substantially cylindrical apertures for engaging the periphery of said blanking punches.

'7. The combination of claim 6 in which the means for holding said blanking punches from vertical displacement includes a widened foot portion on said blanking punches adjacent to said die shoe, and groove means in said notches on said base members for cooperation with said widened foot portion.

8. The combination of claim 5 in which means are provided for clamping said die base members together, a rubber plate mounted on said base members and having apertures therein through which the upper ends of the blanking punches may extend, a stripper plate mounted on said rubber plate and having apertures therein in alignment with the apertures in said rubber plate, the upper ends of said blanking punches being received in the apertures of said stripper plate, and a portion of said stripper plate lying above the plane of the upper surfaces of said blanking punches.

9. In a punch and die mechanism the improvement comprising: a split die base including a pair of members removably mounted on the die shoe of the mechanism, a plurality of notches in each of the members of the split die base, a plurality of exchangeable blanking punches mounted in said notches of said die base, and

anser/,0121i means for-holding saidl blanking punches fromI vertical displacement, and in which the split' die base is provided with a plurality of aperturesy therethrough, dowels mounted ini some of the apertures for positioning the base on the shoe and screws for securing the base in position passing through others of said apertures, in which one of said members has one side in juxtaposition to one side of the other of said members, and said notches being substantially semi-cylindrical and positioned along each of said sides forming substantially cylindrical apertures for engaging the periphery of said blanking punches; in which the means for holding said blanking punches from vertical displacement includes a widened foot portion on said blanking punches adjacent to said die shoe, and groove means, in said notches on said base members for cooperation with said widened foot portion.

10. In a punch and die mechanism the improvement comprising: a split die base including a pair of membersV removably mounted on the die shoe of the mechanism, a plurality of notches in each of the members of the split die base, a plurality of exchangeable blanking punches mounted in said notches of said die base, and means for holding said blanking punches from vertical displacement; in which the means for holding said blanking punches from vertical displacement includes a widened foot portion on o said blanking punches adjacent to said die shoe, and groove means in said notches on said base members for cooperation with said widened foot portion; in which means are provided for clamping said die base members together, a Vrubber plate mounted on said base members and having apertures therein through which the upper ends of. the blanking punches may extend, a stripper plate mounted on said rubber plate and'having apertures-1 therein in alignment with the apertures in saidl rubber plate, the upper ends of said blanking punches being received in the apertures of said stripper plate, and a portion of said stripper'plate lying above the plane of the upper surfaces of said blanking punches.

RALPH A. CARRIER, JR.

DREYFUS C. DAVIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED 'STATES PATENTS Number Name Date 507,260 Coleman Oct. 24, 1893 679,699 Mason July 30, 1901 727,931 Fraser May 12, 1903 1,989,412 Gruchacz Jan. 29, 1935 2,111,156 Schneider Mar. 15, 1938 FOREIGN PATENTS Number `Country Date 215,517 Great Britain May 15, 1924