US3119293A

US3119293A - Punch and die for presses

Info

Publication number: US3119293A
Authority: US
Inventors: Delbert R Allen; Fritz V Brosseit
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1961-10-18
Filing date: 1961-10-18
Publication date: 1964-01-28
Anticipated expiration: 1981-01-28

Description

2 Sheets-Sheet 1 L .E'N

D. R- ALLEN ETAL PUNCH AND DIE FOR PRESSES INVE'N I7. F?- FL 1 \l E D555! 7" Jan. 28, 1964 Filed Oct. 18, 1961 J J 'T'UFQNE' Jan. 28, 1964 Filed Oct. 18, 1961 D. R. ALLEN ETAL PUNCH AND DIE FOR PRESSES 2 Sheets-Sheet 2 p l L JV IN VENTURE,

M 111-7. F7L L.E'N

F. v. E 555/7 United States Patent Ofiiice 3,119,293 Patented Jan. 28, 1964 York Filed Oct. 18, 1961, Ser. No. 145,891 4 Claims. (Cl. 83-131) This invention relates to punch and die for presses, particularly double punches and associated structures for removing punched parts from dies.

One of the major problems in punching parts from sheet or strip stock is the removal of the parts from the area of the punch and die as rapidly as possible during each operating cycle. The solutions to these problems depend largely upon the part being formed or punched and its inherent tendency to remain with the die or in the stock. If the parts are simple in structure and forced through hollow dies, the solution of the problem is obvious, but when this is not possible and when the part is to be formed as well as blanked from the material, additional means must be provided to assure removal of the part, not only from the die but the material, and e'ection of the part so that it may be removed readily from the area of the press.

The object of the present invention is a punch and die which is simple in structure yet highly efficient in controlling the removal of the parts from the punch and die.

In the present embodiment of the invention according to the object, a double punch including a first punch and a second punch associated with a single die therefor are supported by a punch holder mounted on the ram of a press and under the control of a unit to restrict relative movements of the punches so that the parts may be held by one punch and removed from the die after which the unit may be operated to cause the other punch to force the part free.

More specifically, the second punch is fixed on the punch holder and has a portion movable in and through an aperture of the first punch. Furthermore, the unit controls the movement of the first punch between an up position where the portion of the second punch extends beyond the aperture of the first punch to perforate the part and cause the part to cling to this portion and thereby be removed from the die and the strip of material. Subsequently, the unit is operated to move the first punch relative to the second punch as the ram approaches its up position to cause the first punch to force the part free of the second punch.

Other objects and advantages will be apparent from the following detailed description when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a vertical sectional view of the punch and die mounted in a press and shown at the center of its operating cycle;

FIG. 2 is a vertical sectional view of the structure, shown in FIG. 1, illustrating the relative positions of the parts at the beginning and end of each operating cycle;

FIG. 3 is a fragmentary sectional view of the punches with a part held thereon; and

FIG. 4 is an isometric view of one of the parts.

In the present instance, there is a double punch beginning with a stripper apertured for a first punch 11 and a second punch 12 fixedly mounted at 14 on a punch holder 15 which is supported by a bed 16 of a press having a ram 17 operable through reciprocating cycles between positions shown in FIG. 2 and FIG. 1.

The punch 12 is provided with a suitable table 19 and guides 20 mounted thereon for the strip of mate rial 21, from which parts 22 are to be punched and formed through the aid of the punches 11 and 12 and their respective dies, The table 19 is supported on rods 23 and held by springs 24 normally in its up position. A stripper 25 for the punch 12 carrying pins 26 is held upwardly normally by a spring 27 to cause the pins to engage the material 21 and move it above the second punch 12 after each downward movement of the ram so that through conventional means, the strip of material 21 may be advanced the desired distance.

In the present instance, the punches and dies are to punch the circular part 22 from the material 21, punch the downwardly projecting tabs 28, form the elongated aperture 29 therein through the aid of the first punch 11, and form the projections 30 upon each side of the aperture 29 through the aid of forming portions 31 in the second punch 12 with their rounded upper ends cooperating with apertures 32 in the stripper 10.

The stripper 10 is provided with an aperture 35 into and through which a portion 36 of the first punch 11 may be disposed. A die for the portion 36 of the first punch 11 is formed in the stationary second punch 12, as shown in FIG. 1. The first punch 11 is fixedly mounted on a member 37 disposed in

members

38 and 39 of a punch holder, indicated generally at 40, and fixedly mounted in the ram 17. The member 38 has a central vertical aperture in which the stripper 10 is movably disposed, the lower portion of this aperture serving as a die for the second punch 12. The punch holder 43 includes a lateral member 41 supported in a conventional manner on guide rods 42 through the aid of tubes 43.

The important features for consideration are the fixed mounting of one of the punches, namely the second punch 12, and the movable mounting of the other punch, namely the first punch 11 and its stripper 10. The stripper 10 is associated with and under the control of a unit, indicated generally at 45, so that the stripper will be in its down position at the start of each operating cycle to cooperate with the second punch 12 in performing its blanking and forming operations following which the first punch 11 will perform its punching or perforating operation to form the aperture 29. At the end of the first half cycle of the ram 17, the first punch remains in its extended position relative to the stripper 10, shown in FIG. 1, with the portion 36 of the punch 11 projecting through the aperture 35 and through the part 22 so that the part will cling to the portion 36 and be removed from the material 21 and the punch 12 during the second half cycle or upward stroke of the ram 17.

The unit 45 includes a latch 46 pivotally supported at 47 in a recess or hollow portion 48 of a member 49 movable vertically in apertures of the punch holder 40. The member 49 has an enlarged lower portion 50 positioned to engage spaced pins 51 extending through apertures of the

members

37 and 39 where the lower ends of the pins engage the upper surface of the first punch 13. A spring 53, disposed concentric with a reduced portion of the member 49, is compressed between a shoulder 54 of this member and a threaded end or guide 55 to serve as a cushion between the unit 45 and the ram 17. A retaining member 58 of the unit is slidable vertically in an aperture 59 of the member 49 between limits controlled by a pin 60, fixed to the member 49, and extending through an elongated aperture 61 in the member 58.

A spring 62 disposed concentric with the member 58 and interposed between a shoulder 63 of the member 58 and an upper end 64 of the member 49 normally urges the unit 45 to expand by urging the member 58 up- Wardly to its top position shown in FIG. 1. The member 58 has a cutaway portion 66 of the contour shown adapted for interengagement with a portion 67 of the latch 46 to hold the unit locked in its contracted position, the position shown in FIG. 2 which conditions the stripper and the first punch 11 for the start of its operating cycle. The latch 46 has another function of holding the member 49 of the unit in its up position when the unit is expanded, as shown in FIG. 1, so that the stripper 10 may rest on the part 22 held, as shown in FIG. 3, by the first punch 11 during the major portion of the upper stroke or the second half-cycle of the press. This is accomplished by a projection 70 resting on a shoulder 71 of the adjacent member of the tool holder 40. The latch is caused to move into this position by a spring 72 when the shoulder 71 has been moved during the downward stroke of the ram 17 to locate the shoulder beneath the projection 70.

Furthermore, the lower end 73 of the member 58 engages the adjacent portion 67 of the latch to positively hold the latch in this position until the ram moves upwardly a distance sufficient to cause the upper end of the member 58 to strike a stationary element 75 extend ing through an opening 76 in the ram and supported by suitable means 77. Therefore, with the latch 46 in its second holding position, shown in FIG. 1, the stripper 10 will be allowed to ride upwardly on the part 22 held by the portion 36 of the first punch 11 until the member 58 strikes the element 75, holding the member 58 against further movement and permitting the latch 46 to find its way into the position shown in FIG. 2 where it may be permitted to ride off the shoulder 71, thus locking the unit 45 in its compressed position whereby the final movement of the ram upwardly will cause the pins 51 to hold the stripper 10 against further movement, while the first punch 11 completes its upward movement with the punch holder and ram to render the stripper effective to strip the part forcibly from the first punch and to permit it to fall free as shown in FIG. 2. At this time, a blast of air toward the falling part from an air nozzle 80 will force the part out of the area of the punch and die.

Operation At the beginning of each operating cycle (which includes a downward and an upward movement of the ram 17), the portion 67 of the latch 46 engages the cutaway portion 66 of the retaining member 58, as shown in FIG. 2. Such engagement is maintained against the action of the spring 72 by the walls of the aperture 59, which walls slidably contact the projection 70 of the latch 46. This contact by the walls of the aperture 59 prevents, at this time, clockwise pivotal movement of the latch 46. Moreover, the engagement of the portion 67 with the cutaway portion 66 permits the spring 53 to expand. This expansion enables the enlarged portion 50 of the member 49 to push the pins 51 downwardly, resulting in the extension of the stripper 10 below the face of the die 38, as illustrated in FIG. 2.

As the ram 17 descends, the stripper 10 initially con tacts the strip of material 21 and fixedly holds such material 21 stationary with respect to the second punch 12. Further downward movement of the ram 17 compresses the spring 53 to retract the stripper 10 against the material 21. As the stripper 10 retracts, the portion 36 of the first punch 11 contacts the material 21 and cooperates with the die of the second punch 12 to form the aperture 29 in the material 21. Additional downward movement of the ram 17 brings the die 38 into contact with the material 21; whereupon, such die 38 cooperates with the second punch 12 to blank the part 22 from the material 21 Such further downward movement of the ram 17 also moves the shoulder 71 under the projection 70 of the latch 46, resulting in the clockwise pivotal movement of the latch 46 under the force,

l of the spring 72. This pivotal movement of the latch 46 enables the projection 70 to ride on the shoulder 71, as shown in FIG. 1.

Next, the ram 17 moves upwardly and the projection 70 remains on the shoulder 71. The portion 73 of the retaining member 58 contacts the portion 67 of the latch 46 to maintain the latch in its clockwise position. With the latch 46 in its clockwise position, the stripper 10 remains retracted relative to the portion 36 of the punch 11. Since the stripper 10 is so retracted, the portion 36 of the punch 11 carries the part 22 above and out of the way of the material 21 and the table 19.

As the rain proceeds upwardly, the retaining member 58 abuts the stationary element 75, resulting in the downward pushing of the retaining member 58 against the action of the spring 62. Such downward pushing of the retaining member 58 coupled with the additional upward movement of the ram 17 forces the portion 73 of the retaining member to move beyond the portion 67 of the latch 46 to engage a cutaway portion of such latch 46. Moreover, this downward pushing and continued upward movement of the ram 17 moves a slightly rounded corner of the shoulder 71 against the projection 70 to pivot the latch 46 counterclockwise and force the projection 70 off the shoulder 71. Thereupon the spring 53 expands to extend the stripper 10 below the face of the die 38 to eject the part 22 from the portion 36 of the punch 11. After the part 22 is ejected from the portion 36 of the punch 11, the part 22 is blown out of the Work area by a blast of air from the nozzle 80.

It is to be understood that the above described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. A double punch and die comprising:

a stripper having an aperture,

a first punch movable within the aperture of said stripper for forming an opening in a part and for subsequently and momentarily carrying the part,

a second punch mounted at a fixed position in alignment with the first punch and having a first die formed therein for receiving said first punch,

a second die having an aperture for movably receiving the stripper and for moving beyond the face of the second punch to blank the part from a strip of material,

control means for normally extending the stripper beyond the second die and the first punch and for permitting retraction of the stripper relative to said second die and first punch,

a ram fixed to the first punch and second die and movable toward the fixed second punch for pressing the extended stripper against the strip of material to retract said stripper and for extending said first punch into the first die to form the opening in and carry the part and for extending said second die beyond the face of said second punch to blank the part from the strip, said ram being subsequently movable away from said second punch,

a stationary element fixed relative to said second punch,

a retaining member slidably mounted within said ram for abutting against the stationary element, and

a latch engaging the retaining member for maintaining said stripper retracted during the upward movement of the ram and being subsequently released by the abutting of the retaining member against the stationary member after a predetermined upward movement of the ram to render effective said control means to extend said stripper to eject said carried part from said first punch.

2. A double punch and die comprising:

a stripper having an aperture,

first punch movable within the aperture of said stripper for forming an opening in a part and for subsequently and momentarily carrying the part, second punch mounted at a fixed position in alignment with the first punch and having a first die formed therein for receiving said first punch, second die having an aperture for movably receiving the stripper and for moving beyond the face of the second punch to blank the part from a strip of material,

control means for normally extending the stripper beyond the second die and the first punch and for permitting retraction of the stripper relative to said second die and first punch, said control means including a spring resiliently urging said stripper beyond the second die and first punch,

ram fixed to the first punch and second die and movable toward the fixed second punch to press the extended stripper against the strip of material to compress said spring to retract said stripper and to extend said first punch into the first die to form the opening in and carry the part and to extend said second die beyond the face of said second punch to blank the part from the strip, said ram being subsequently movable away from said second punch,

a stationary element fixed relative to said second punch, a retaining member slidably mounted within said ram for abutting the stationary element and having a spaced portion, holding member shoulder, and

fixed to the ram and having a a latch having a spaced portion engaging said spaced portion of the retaining member and having a projection for fixedly contacting the shoulder of said holding member to maintain said spring compressed and said stripper retracted during the upward movement of the ram, said projection being subsequently released by the stationary element after a predetermined upward movement of the ram to render effective said control means to extend said stripper to eject said carried part from said first punch.

. A double punch and die comprising:

stripper having an aperture,

ram fixed to the second die and first punch and movable toward the fixed second punch for pressing the extended stripper against the strip of material to retract said stripper and for extending the first punch into the first die to form the opening in and carry the part and for extending said second die beyond the face of said second portion to blank the part from the strip, said ram being subsequently movable away from said second portion,

a stationary element fixed relative to said second punch,

a retaining member slidably mounted within said ram for abutting the stationary element and having a spaced portion,

a holding member fixed to the ram and having a shoulder, and

a latch having a spaced portion engaging said spaced portion of the retaining member and having a projection for fixedly contacting the shoulder of said holding member to maintain said stripper retracted during the upward movement of the ram, said projection being subsequently released by said stationary member after a predetermined upward movement of the ram to render effective said control means to extend said stripper to eject the carried part from the first punch.

4. A double punch and die comprising:

a stripper having an aperture,

a ram fixed to the second die and first punch and movable toward the fixed second punch for pressing the extended stripper against the strip of material to retract said stripper and for extending the first punch into the first die to form the opening in and carry the part and for extending said second die beyond the face of said second portion to blank the part from the strip, said ram being subsequently movable away from said second portion,

a stationary element fixed relative to said second punch,

a retaining member slidably mounted within said ram for abutting against the stationary element, and latch means responsive to the retraction of the stripper for maintaining said stripper retracted during the upward movement of the ram and being subsequently released by the abutting of the retaining member against the stationary element after a predetermined upward movement of the ram to render efiective said control means to extend the stripper to eject the carried part from said first punch.

References Cited in the file of this patent UNITED STATES PATENTS 1,428,174 Luther Sept. 5, 1922 1,503,829 Heald Aug. 5, 1924 1,933,465 Woodburn Oct. 31, 1933 2,699,830 Hodge Jan. 18, 1955

Claims

1. A DOUBLE PUNCH AND DIE COMPRISING: A STRIPPER HAVING AN APERTURE, A FIRST PUNCH MOVABLE WITHIN THE APERTURE OF SAID STRIPPER FOR FORMING AN OPENING IN A PART AND FOR SUBSEQUENTLY AND MOMENTARILY CARRYING THE PART, A SECOND PUNCH MOUNTED AT A FIXED POSITION IN ALIGNMENT WITH THE FIRST PUNCH AND HAVING A FIRST DIE FORMED THEREIN FOR RECEIVING SAID FIRST PUNCH, A SECOND DIE HAVING AN APERTURE FOR MOVABLY RECEIVING THE STRIPPER AND FOR MOVING BEYOND THE FACE OF THE SECOND PUNCH TO BLANK THE PART FROM A STRIP OF MATERIAL, CONTROL MEANS FOR NORMALLY EXTENDING THE STRIPPER BEYOND THE SECOND DIE AND THE FIRST PUNCH AND FOR PERMITTING RETRACTION OF THE STRIPPER RELATIVE TO SAID SECOND DIE AND FIRST PUNCH, A RAM FIXED TO THE FIRST PUNCH AND SECOND DIE AND MOVABLE TOWARD THE FIXED SECOND PUNCH FOR PRESSING THE EXTENDED STRIPPER AGAINST THE STRIP OF MATERIAL TO RETRACT SAID STRIPPER AND FOR EXTENDING SAID FIRST PUNCH INTO THE FIRST DIE TO FORM THE OPENING IN AND CARRY THE PART AND FOR EXTENDING SAID SECOND DIE BEYOND THE FACE OF SAID SECOND PUNCH TO BLANK THE PART FROM THE STRIP, SAID RAM BEING SUBSEQUENTLY MOVABLE AWAY FROM SAID SECOND PUNCH, A STATIONARY ELEMENT FIXED RELATIVE TO SAID SECOND PUNCH, A RETAINING MEMBER SLIDABLY MOUNTED WITHIN SAID RAM FOR ABUTTING AGAINST THE STATIONARY ELEMENT, AND A LATCH ENGAGING THE RETAINING MEMBER FOR MAINTAINING SAID STRIPPER RETRACTED DURING THE UPWARD MOVEMENT OF THE RAM AND BEING SUBSEQUENTLY RELEASED BY THE ABUTTING OF THE RETAINING MEMBER AGAINST THE STATIONARY MEMBER AFTER A PREDETERMINED UPWARD MOVEMENT OF THE RAM TO RENDER EFFECTIVE SAID CONTROL MEANS TO EXTEND SAID STRIPPER TO EJECT SAID CARRIED PART FROM SAID FIRST PUNCH.