US2468620A - Stamping press - Google Patents

Description

April 1949- A. J. GILBERT ET AL 2,4

STAMPING PRESS Filed March 13, 1947 i 3 Sheets-Sheet l INVENTORS AcoN/fls I GILBERT a= CQSPER MEHLUM m BY? AT RNEY A. J. GILBERT ETAL April 26, 1949 I STAMPING PRES S 3 Sheets-Sheet 2 Filed March 15, 1947 INVENTORS N/HS JT GILBERT 8:

CI SPER MEHLUM 4 W ATTORNEY April 9. A. J. GILBERT AL 2,468,620

STAMPING PRESS Filed March 13, 1947 5 Shets-Sheet 5 ,qbcwms J GILBERT8= ans/ 5, MEHLUM ATTORN EY Patented Apr. 26, 1949 STAMPING PRESS Adonias J. Gilbert, Newtonville, and Casper Mehlum, Waltham, Mass; said Mehlum assignor to said Gilbert Application March 13, 1947, Serial No. 734,486

9 Claims.

This invention relates to stamping presses for the stamping or punching of strip stock and is directed more particularly to novel and efilcient means for feeding strip stock of metal, plastic or other material, to and from stamping or punching dies in such manner that the successive operations of the dies are very accurately spaced longitudinally of the stock.

The primary object of the present invention is to provide a machine for the purposes stated which shall be remarkably simple, yet absolutely accurate and smoothly operating.

Speaking generally, the feed of stock, according to the present invention, is accomplished by a pivoted feeder adapted to be oscillated about fixed pivots and so constructed as to grip the strip stock in one position, feed. it forwardly, and then return to the initial gripping position. This feeder has fixed and movable jaws, so constituted that their gripping faces remain substantially parallel to the direction of feed of the stock and this precludes crimping of the stock while in gripping cooperation with the jaws.

The machine of this invention further embodies a holding mechanism for gripping and holding the stock during retrograde movement of the feeder, so as to eliminate idle movement of the strip at any time and to hold the stock stationary as successive portions thereof are acted upon by the dies.

An important feature of the machine of this invention is that it embodies a single operating cam shaft from which single shaft all operating parts of the machine are actuated. This shaft actuates said parts through a series of cams and eccentrics, properly timed so that the parts are operated in proper timed synchronized sequence. The use of a plurality of shafts and a large number of gears heretofore considered necessary in machines of this general character, is thereby rendered unnecessary and much less power is required to operate the machine than heretofore.

Features of the invention, other than those adverted to, will be apparent from the herein-v after detailed description and appended claims; when read in conjunction with the accompanying drawings.

The accompanying drawings illustrate one practical embodiment of the invention, but the construction therein shown is to be understood as illustrative, only, and not as defining the limits of the invention.

Figure 1 is a perspective view of the machine of this invention, certain portions of which are broken away in the interest of clearness.

Figure 2 is a front elevation of the machine of Figure 1.

Figure 3 is a plan view of the machine.

Figure 4 is an elevation of the machine on a somewhat enlarged scale, as viewed from the right hand end of Figures 2 and 3.

Figure 5 is a section on the line 5-5 of Figure 1.

Figure 6 is a section on the line 6-6 of Figure 1.

Figure '7 is a section on the line ll of Figure l.

The machine of this invention comprises end frames or standards I and 2 which are spaced apart by spacing rails 3, 4, 5, 6, l and 8, the opposite ends of which are bolted to the end frames. Supported on the two rails 3 and 4, at one end of the machine, is a table 10 on which is mounted a die couple comprising a fixed die member I l and a movable die member 12. The movable die member I2 has an upstanding boss I3 to which is secured one end of an operating lever 14. The lever is pivoted intermediate its ends upon a vertically adjustable standard l5 mounted on the table II), while the other end of said lever is pivoted to an operating eccentric hereinafter dee scribed.

Mounted on the rails 3 and 4 at the opposite end of the machine is a table Illa which supports a holder 16. This holder comprises a fixed jaw I1 and a movable jaw l8. The movable jaw is secured to one end of a lever l9 mounted on a pivot 20, while the other end of such lever is secured to a link 2|, operated as hereinafter described. Interposed between the table Ilia and the power arm of the lever [B is a spring 22 which normally tends to elevate the power arm of the lever and lower the movable jaw 18 into engagement with strip stock S adapted to be passed between said jaws.

The strip stock S may be conveniently fed from a feed roll F, indicated in phantom at the left of the machine in Figure 2 across and above the tables in and Illa to a take-up roll T indicated in the same figure, so that it is uncoiled from the feed roll, stamped or punched during its passage through the machine and then coiled upon the take-up roll T. These-rolls F and T may conveniently be in the form of reels, operated in any suitable manner, the belt t being indicated in Figure 3 as a driving means for the roll T and acting upon'this roll through a suitable friction clutch (not shown).

Extending horizontally from front to back of the machine is a single cam shaft 23 supported to rotate in bearings 24 carried by the rails 5 and 6 (Figure 3). To the rear end of theshaft is fixed a gear'25 which meshes with a gear 25 carried by a shaft 2'1. This shaft Z'l is mounted in bearings 28 also fixed on the rails 5 and 6. Mounted on the shaft 2?, which is in effect a countershaft, is a pulley 29 adapted to be driven by a belt til which is in turn driven by a motor 3i which constitutes the prime mover of the machine. The gears and 26 are speed reduction gears, so that the machine may be operated to feed the strip S at a convenient speed. Any other suitable form of drive, such, for example, as a worm and worm Wheel might be used to eliminate the speed reduction gearing show-n, entirely.

On the cam shaft 23 are fixed three cams 32, 33 and 34 and also an eccentrically mounted disk 35 of an eccentric. The eccentric 35 is embraced by the usual strap 3t connected by a conventional pitman 3? to the power arm of the operating lever i l which operates the die it, so that the movable member E2 of the die couple will be raised and lowered with a smooth easy movement. A cam may also be used for this purpose :inlieu of the eccentric 35 which may be conveniently referred to as a cam.

The cam 32 is for operating the feeder. It is shown as an eccentrica'lly supported disk adapted to coact with a cam follower 38 mounted onan arm 39. The lower end of this arm is pivoted to a plate 9 supported :on rods 9a which extend through the rails 1 and =8, as shown best in'Fi-gure l. The upper end of the arm 39 is connected by a link it] to the strip feeder presently described. The connection between the link it and the arm 39 is shown in detail in Figure 7. Here 'it'will' be noted that the link 49 carries ablock l! guided in a vertical slot 42 in the upper portion of the arm 39 and a screw' ls passes downwardly through the top of the slot and through the block 44. By rotation of the screw 43, the block a! maybe raised or lowered to vary the throw of the link and the consequent throw or travel 'of-the feeder.

The feeder comprises two spaced apart parallel arms 44 and 45, each of which is'pivoted at its lower end to the plate 9, as shown best in Figures 1, 2 and '5. The link Ml is pivoted to the arm 45 which has a series of'per-forations, any one o f which the pivot of the link. 49 may occupy to further the throw of the feeder, as desired.

The arms 44 and 45 extend upwardly to a'poi-nt above the plane of the table It and carry relatively fixed and movable jaws. The fixed-jaw M5 is adapted to lie below the plane of the strip- S while th movable jaw ll 'lies'a'bove 'thestri-p. The jaw i6 is secured to the arms 44 and ifi by pivots All which pivots are at the same elevation, so that, when the arms are oscillated about their lower pivots, they will form with the rail and the fixed jaw 46 a parallelogram, so that the fixed jaw 38 will at all times occupy a horizontal post tion substantially orslightlybelow the plane of the strip S. The upper jaw #7 has a depending rigid stem 49"(see Figures l and! whichextends downwardly through an a'lined perforation in the lower jaw as and has a reduced threaded end hil terminating in a ball 5|. An adjusting "nut 52 is screwed onto the threaded stem and acts against a spring 53 which normally tends to lower the upper jaw 4'! and cause it to grip-the strip S against the lower jaw 16 (Figure 5).

Embracing the ball 5! at the lower end of the stem is a socket formed in the upper end'of a push rod 53. The lower end of this push rod makes a ball joint connection M with abracket 55 rigidly secured' to the outboard end of a lever 1 stock.

phase, thereby permitting the spring 53 to lower the upper jaw 4? of the feeder into gr ping rela tion, with the strip, so that said strip is fed forw-ar'dly a distance controlled by the adjustment of the screw it of Figure 7. At the end of the forward movement of the feeder, the high phase 'of the cam .33 engages the cam follower lit and acts upon a push rod 53 to disengage the feeder jaws from the strip stock, so that, during a return or retrograde movement of the feeder under the pull of the spring 38a, the strip is released. The timing is such that, during this periodw-lren th strip is released and at rest, the eccentric 35 will act uponthe die I 2 to effect the stamping or punching operation.

There is apt to besome drag of the feeder. on the strip during such retrograde movement and the present invention provides means for holding the strip stationary against this drag to provide for accurate stamping or'punching by the die couple. The holder, -indicated at Ill, performs this function and its movable jaw i8 is controlled by the link '2! hereinbefore referred to. This link is pivoted at its lower end to an arm (is; one .end of which, like the ar-m':58, is pivoted on :a Ifixed rod 6!, while the other end of the arm 60 carries a cam fOllowerBZ coacting with the cam 34 (Figure 1). The cams 33'and 34l are set oppositely so that when the high phase of the cam 33 is cooperating with its follower 59 to release the strip stock during the retrograde movement of the feeder, the low phase vof the cam 34 will be presented to its follower 62 to permit the spring 22 to cause the jaw I8 of the holder to grip the In this way the stockis immobilized during the punching or stamping operation and the coincidentretrograde movement of the feeder.

However, as the high phase of the cam 33 leaves its follower F59 and permits the feeder jaws to grip the stock for the next forward feed thereof, the

high phase of the :cam't l engages its follower 62 and lifts the movable jaw it of the holder free of the stock to permit the stock to be fed. In this way the parts are synchronized for intermittent co-related operations, successively coasting with one another to intermittently feed and punch the stock. In practice the machine operates smoothly, without appreciable vibration and with practically no noise except that incident to ordinary die'operation. .The feed is absolutely'accurate' and uniform.

Thestrip operated upon-thy this invention may be used for a wide variety of purposes. For'example, we'have employed-it for the cuttingxof razorblades from stripstock, inwhich operation itis convenient-toynotch' thezedges 'of'the stock and stamp out holes for the safety razorpinsor other holdin deviceaduring continuous operation and thereafter andrat some subsequent operation,separate the thus formed blades from the strip stock. Our experience in thus manipu lating razor blades has indicated'the remarkable accuracyof the machine of this invention.

The foregoing detailed description" sets forth the invention in its" preferred practical form, but

the invention is to be understood as fully commensurate with the appended claims.

Having thus fully described the invention, What we claim as new and desire to secure by Letters Patent is:

1. A machine for feeding and stamping strip stock comprising: fixed and movable jaws of a die couple, a feeder having relatively fixed and movable jaws normally spring impelled to grip the strip, a single cam shaft, an eccentric on said shaft with operative connections with the movable member of the die couple, a cam on said shaft with an operative connection with the .feeder to move the jaws collectively relative to the die couple to feed the strip, and another cam on said shaft with operative connections with the movable jaw of the feeder to release the strip from the grip of the jaws between feeding operations.

2. A machine for feeding and stamping strip stock comprising: fixed and movable jaws of a die couple, a feeder having relatively fixed and movable jaws normally spring impelled to grip the strip, a single cam shaft, an eccentric on said shaft with operative connections with the movable member of the die couple, a cam on said shraft with an operative connection with the feeder to move the jaws collectively relative to the die couple to feed the strip, and another cam on said shaft with operative connections with the movable jaw of the feeder to release the strip from the grip of the jaws between feeding opertions, in combinations with a normally spring impelled holder to grip the strip between feeding operations, and another cam on said shaft with connections with the holder to release the strip during feeding operations.

3. A machine for feeding and stamping strip stock comprising: a die couple embodying relatively fixed and movable members between which the strip is fed, a feeder embodying fixed and movable jaws between which the strip extends, a holder embodying fixed and movable jaws between which the strip also extends, said die couple, feeder and holder being arranged in spaced relation longitudinally of the strip, a cam shaft carrying a plurality of cams, operative connections between the die couple and one of said cams, an operative connection between the feeder and another of said cams, and an operative connection between the movable jaw of the feeder and another of said cams, said cams being operable to feed the strip when the die and holder are disengaged from the strip and to disengage the feeder from the strip while the die couple and holder are engaged with the strip.

4. A machine for feeding and stamping strip stock comprising: a die couple, a feeder embodying relatively fixed and movable jaws mounted on parallel arms of equal length pivoted to a fixed support at a distance from the jaws and the fixed jaw being pivoted to the respective arms, a stem on the movable jaw extending through and guided in the fixed jaw and spring impressed to normally close said jaws, a push rod connected to said stem for opening said jaws, a cam, a cam follower cooperating with said cam and mounted on a pivoted arm having link connection with the follower to cause said follower to be moved about its pivotal support for the purpose of feeding the strip, a second cam acting upon a follower having a leverage connection with the push rod to release the strip from the grip of the feeder jaws, and means for retracting the feeder when the strip is thus released, an eccentric connected to the die couple, and a single cam shaft for supporting and operating both of said cams and the eccentric.

5. A machine for feeding and stamping strip stock comprising: a die couple, a feeder embodying relatively fixed and movable jaws mounted on parallel arms of equal length pivoted to a fixed. support at a distance from the jaws and the fixed jaw being pivoted to the respective arms, a stem on the movable jaw extending through and guided in the fixed jaw and spring impressed to normally close said jaws, a push rod connected to said stem for opening said jaws, a'cam, a cam follower cooperating with said cam and mounted on a pivoted arm having link connection with the follower to cause said follower to be vmoved about its pivotal supports for the purpose of feeding the strip, a second cam acting upon a follower having a leverage connection with the push rod to release the strip from the grip of the feeder jaws, means for retracting the feeder when the strip is thus released, an eccentric connectedto the die couple, a single cam shaft for supporting and operating both of said cams and the eccentric, a third cam also on said cam shaft having a cam follower, a holder for normally gripping the strip, and connections between the holder and the last mentioned cam follower for releasing the strip while the latter is fed by the feeder.

6. A machine for feeding and stamping strip stock comprising: a cam shaft, an eccentric on said shaft, a lever connected to said eccentric, a die connected to the lever to act upon the strip, a cam on said cam shaft, a cam follower coacting with said cam, a holder controlled by said follower for gripping and immobilizing the strip while it is acted upon by the die, a second cam on said cam shaft having a follower coacting therewith, a pivoted arm on which the latter follower is supported, a link secured to said arm, and a feeder secured to the distant end of said link to feed the strip to the die, a spring for retracting the feeder in the opposite direction, said feeder carrying a pair of relatively movable jaws, and a third cam on the cam shaft with operative connections between it and said relatively movable jaws to cause them to engage and grip the strip and feed the same when the feeder is advanced in one direction and to disengage the jaws from the strip when the feeder is retracted in the opposite direction.

7. A machine for feeding and stamping strip stock comprising: a cam shaft, an eccentric on said shaft, a lever connected to said eccentric, a die connected to the lever to act upon the strip, a cam on said cam shaft, a cam follower coacting with said cam, a holder controlled by said follower for gripping and immobilizing the strip while it is acted upon by the die, a second cam on said cam shaft having a follower coacting therewith, a pivoted arm on which the latter follower is supported, a link secured to said arm, a feeder secured to the distant end of said link to feed the strip to the die, a spring for retracting the feeder in the opposite direction, said feeder carrying a pair of relatively movable jaws, and a third cam on the cam shaft with operative connections between it and said relatively movable jaws to cause them to engage and grip the strip and feed the same when the feeder is advanced in one direction and to disengage the jaws from the strip when the feeder is retracted in the opposite direction, and means for adjusting the throw of the feeder aeeegaao 7 to vary the length of strip'ied at ea-ch'ioperation thereof.

8. A machine for feeding and stamping strip stock comprising: a die couple, a lever for operating said coup'le,.a pairlof' re'lativel'y movable jaws for feeding strip stock between the couple, parallel arms :mounted'on-spaced" apart pivots on a fixed support and pivoted "to onezofssaid jaws with the pivots of the jaws spacedapart "the same distance as the pivots. of the arms and the pivots on both arms being equally spaced apart, :means for'oscillating said arms to move the jaws along the'path offeed of the strip, meansior forcing the jaws together to grip and feed the-strip one direction, and means to separate the jaws during oscillation of the arms inxa retrograde direction.

*9. A machine for feeding and stampingstrip stock comprising: a die couple, alever i'oroperating said-couple, a pair of relatively movable jaws for feeding strip stock between the couple, parallel arms mounted on spaced apart-pivots on a fixed support and pivoted to one of'said-ja-ws with the REFERENCES CITED 'The following references are of record in'the file of this patent:

UNITED STATES PATENTS Number Name Date 641,333 Saltzkorn Jan. 16, 1900 838,340 Leroy Dec. 11, 1906 1,344,492 Edgar June 22; 1920 2,359,140 Meitner Sept. 26, I944

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