US 3516317 A
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Description (OCR text may contain errors)
June 23; 1970 N. E. SUNDQUIST ET AL 3,516,317
CORNER ROUNDING PUNCH AND DIE ASSEMBLY Filed May 51. 1968 2 Sheets-Sheet 1 FIG: 5'
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lV/LS E. SUN-D 00/5 7' Gill/7041f. P4775850 BMJQK 3M L J /8 54 I June 23, 1970 E, su nqu s ET AL 3,516,317
CORNER ROUNDING PUNCH AND DIE ASSEMBLY Filed May 31, 1968 2 Sheets-Sheet 2 JET a.
i glllilllll .umm 11ml Il l 7 4 49 l 27 l W 4 I8 50 53 HHW' II I f //|l il l i M I U l I N VEN TORS FIG 4 AIMS z. smvmpu/sr 4 rroRn/Eys United States Patent 3,516,317 CORNER ROUNDING PUNCH AND DIE ASSEMBLY Nils E. Sundquist and Clinton E. Patterson, Minneapolis,
Minn., assignol's to Mate Punch and Die Co., Minneapolis, Minn., a corporation of Minnesota Filed May 31, 1968, Ser. No. 733,686
Int. Cl. B26d 7/16, 3/10 U.S. Cl. 83-467 14 Claims ABSTRACT OF THE DISCLOSURE A punch and die assembly for rounding the corners of a sheet metal work piece. The assembly has a plurality of cutting positions so that the corners of a work piece be cut to different size radii through the use of a single punch and die. The die has a plurality of aligned arcuate cutting projections of different size radii. The punch has complementary recesses which cooperate with the die projections on movement of the punch toward the die to effect a shearing operation. A guide bar adjusta'bly mounted in selective positions on the die aligns the corner of the work piece with a selected projection so that the corner of the work piece is rounded on movement of the punch toward the die.
SUMMARY OF INVENTION The invention relates to a multiple corner punch and die assembly usable to provide a number of different size radii for the corners of a work piece with a minimum of set up time and Without measurement or adjustment. The
punch and die assembly has a die with a plurality of cutting projections. Each cutting projection is arcuate with a different sized radius. Cooperating with the projections is a movable die having a plurality of arcuate recesses which correspond to the die projections. A gauge bar is selectively mounted on the die in a number of positions to align the corner of the work piece with one of the cutting projections and the cooperating punch recess so that a selected radius is cut on the corner of the work pieceon movement of the punch toward the die.
In the drawings:
FIG. 1 is a fragmentary side view of a punch press set up with the corner punch and die assembly of the invention;
FIG. 2 is an enlarged sectional view taken along the line 22 of FIG. 1 partly broken away to show the punch, the die, and the gauge bar;
FIG. 3 is a front elevational view of the punch and die assembly;
FIG. 4 is a rear elevational view of the punch and die assembly;
FIG. 5 is a sectional view taken along the line 5-5 of FIG. 2;
FIG. 6 is a view similar to FIG. 5 showing the cutting of the work piece; and
FIG. 7 is a sectional view taken along the line 77 of FIG. 3 with the gauge bar removed.
Referring to the drawings there is shown in FIG. 1, a conventional punch press indicated generally at 10 set up with the punch and die assembly of the invention indicated generally at 11. Punch press 10 has a horizontal bottom table 12 located below a power driven movable member 13. On operation of the press 11) the movable member 13 ice is sqeuentially driven toward and away from the table 12 to effect the operation of the punch and die assembly 11.
Punch and die assembly 11 has a base 14 secured to the table 12 and a movable head 16 engaging the bottom of the movable member 13. A die 17 is secured to the base and a punch 18 is attached to the head 16. On operation of the press 10 the punch 18 moves downwardly relative to the die 17 to cut the work piece with shearing forces. The punch and die assembly has a plurality of work positions which are selectively used to provide the corners of sheet work pieces with different size radii. The assembly can be converted to change the radius of the corner of the work piece with a minimum of set up time without measurement or adjustment of any part of the assembly.
Referring to FIGS. 4 and 7, base 14 is a rectangularshaped metal block having a downwardly inclined cutout 19 along one side providing a chute for the waste material, slugs and chips cut from the work piece. Opposite ends of the base 14 have holes 20 for accommodating bolts used to secure the punch and die assembly 11 to the table 12. Projected upwardly from opposite end sections of the base are upright posts 21 and 22 for movably supporting and aligning the head and die on the base. The upper ends of posts 21 and 22 slidably project through bearings 23 and 24 and into bores 26 and 27 respectively, in the head 16. Positioned about the posts 21 and 22 between the bearings and base 14 are coiled springs 28 and 29 respectively which bias the head and die upwardly holding the punch and die assembly in an open position.
As shown in FIG. 4, the die 18 is secured to the bottom of head 16 above the die 17 with a plurality of upright bolts 31. A stop assembly indicated generally at 32 secured to the die 18 functions to limit the upward movement or open position of the die. The details of stop 32, shown in FIG. 5, comprise an upright cylindrical shank 33 having a thread upper end 34 threaded into the mid-section of the die 18. The lower end of shank 33 projects through an upright hole 35 in the base 14. A bolt 36 is threaded into the lower end of shank 33 providing a stop which can adjust the open position of the die. The head of bolt 36 is located in a recess 37 extended upwardly from the bottom of base 14. As shown in FIG. 6, when the die 18 is in the lowered cut position the shank 33 slides through the hole 35 lowering the bolt 36 in the recess 37.
Refening to FIGS. 2 and 7, the die 17 located on base 14 has a flat horiznotal upper surface or platform 38 forming a horizontal support for the work piece 68. Opposite end sections of the dies have upright holes for accommodating bolts 39 used to secure the die to the base 14. The forward side of the die 17 has a plurality of linearly spaced arcuate projections 41, 42, 43, 44, and 46. Each projection has a different radius making the projections of unequal size. The centers of each of the radii of the projections lie along lines that transversely bisect each of the projections.
Punch 18 has an outwardly directed side formed with a plurality of linear spaced upright recesses 47, 48, 49, 5t), 51 and 52 which are complementary in shape to the projections 41-46 whereby the opposing edges of the projections and recesses form coacting cutting edges operable to shear the corner of the work piece.
As shown in FIGS. 3, 5, and 6, each recess opens to an upwardly directed transverse groove 54 in the bottom of the punch 18 extended rearwardly from the punch cutting edge 56. The portions of the punch 18 between the grooves form downwardly projected teeth or heels 57 which extend below the cutting edge 60 of the die 17 when the die is in the open position. This prevents movement of the work piece under the die. The teeth act as stops as well as positioners to locate the corner of the work piece in proper cutting position between the cutting edges of the die and punch. The opposite sides of each recess has chamfered edges 58 which lie along the planes which are normally disposed with respect to each other so that each chamfered edge is positioned approximately 45 from the transverse center line of the recess. The chamfered edges 58 provide fiat surfaces which are tangent to the radii of the recess so that the corner of the work piece can be properly aligned with the cutting edges of the die and punch.
Selectively positioned on the platform 38 is a work positioning gauge bar or line up bar indicated generally at 59. Bar. 59 is in the shape of a flat parallelogram having straight guide edges 61 and 62. The inner end of bar 59 has a vertical pin 63 which extends above and below the bar. Projected downwardly into die 17 are a plurality of longitudinally spaced holes 64 for receiving the downwardly projected portion of the pin 63 to position the guage bar 54 on the die 17. The outer end of bar 59 has a hole for accommodating a bolt 66 turned into one of a plurality of longitudinally spaced threaded bores 67 extended downwardly into die 17. The opposite acute angles of the gauge bar are 45 degrees. When the pin 63 is in one of the holes 64 and bolt 66 is threaded in a coordinated hole 67, one of the side edges 61 or 62 of the bar is aligned with one chamfered edge of one recess of the punch 18. As shown in FIG. 2, the bar 59 is reversible so that all of the cooperating die projections and punch recesses may be used to form corners in the work piece 68. The holes 63 and threaded bores 67 are aligned in pairs with respect to each other whereby the gauge bar 59 may be placed on the die platform 38 in a plurality of left hand and right hand positions so that all of the cooperating projections and recesses may be utilized to form different size rounded corners on the work piece.
In operation, the work piece 68 is placed flat on the platform 38 with the corner portion extended into the groove 54 between heels 57. One edge of the work piece is placed against the side of the gauge bar 59. As shown in FIG. 2, the work piece 68 is placed against the side edge 61 with the corner of the work piece extended into the recess 48 above the projection 42 and the die cutting edge 60. The gauge bar 59 aligns the corner in the recess so that the radius of the recess bisects the corner of the work piece so that a symmetrical round is cut on the work piece. On operation of the press the movable member 13 forces the head 16 down moving the punch 18 toward the base 14. The cutting edge 56 of the punch shears the corner of the work piece. The slug 69 falls under the punch into the chute 19 as shown in FIG. 6. The head 18 moves downwardly against the biasing forces of springs 28 and 29. On release of the force on the member 13, springs 28 and 29 bias the head and punch 18 back to the open position as shown in FIG. 5. This places the punch and die assembly in a position to effect a second shearing operation.
Referring to FIG. 7, the punch and die assembly is usable to round corners of a work piece without the use of the gauge bar 59. The work piece is placed flat on the platform with the corner in punch recess 49 over die projection 43. The fiat side surfaces of the chamfered edges 58, shown in FIG. 3, align the work piece between the punch and die cutting edges so that the corner is cut round.
While there have been shown and described a punch and die assembly with six cooperating corner projections and recess it is obvious to one skilled in the art that any number of cooperating projections and recesses can be provided in the die and punch and the gauge bar 59 can be placed in numerous positions to provide a guide for the work piece. Other changes and modifications can be made by those skilled in the art without departing from the spirit of the invention. The invention is defined in the following claims.
The embodiments of the invention in which an exclusive property is claimed are defined as follows:
1. A punch and die assembly comprising: a die having a plurality of spaced arcuate cutting edges, a punch having a plurality of spaced arcuate cutting edges which c0- incide in shape with the cutting edges of the die, means mounting the punch and die for relative movement toward and away from each other and locating the coinciding die and punch cutting edges in close cutting alignment, guide means selectively attached to the die in one of a number of positions for aligning a corner of a work piece between one cutting edge of the die and the corresponding one cutting edge of the punch whereby on relative movement of the punch and die the corner of the work piece is severed from the work piece.
2. The assembly of claim 1 wherein the die has a plurality of spaced projections, each projection having an arcuate cutting edge, said punch having a plurality of recesses, each recess forming a cutting edge corresponding to the coinciding cutting edge of the projection.
3. The assembly of claim 2 wherein each cutting edge of the projections has a different radius.
4. The assembly of claim 2 wherein the guide means comprise a bar having at least one linear edge and means releasably securing the bar to the die to align the linear edge with one side of a recess whereby a corner of the work piece is positioned between the punch cutting edge and the corresponding die cutting edge.
5. The assembly of claim 4 wherein the releasable means comprises a pin at one end of the bar projected into a hole in the die and a bolt threaded into the die at the other end of the bar.
6. The assembly of claim 4 wherein the bar is a flat parallelogram member having linear side edges selectively usable to align the work piece on the die with a corner of the work piece located between the punch edge and the corresponding die cutting edge.
7. The assembly of claim 2 wherein said punch has teeth located between the arcuate cutting edges of the punch, said teeth have bottom edges projected below the plane of the cutting edges of the die.
8. The assembly of claim 7 including a base, means securing the die to the base, a head, means connecting the punch to the head, a spring biasing the head away from the base, and stop means limiting movement of the punch from the die.
9. The assembly of claim 8 wherein said stop means is adjustable to change the open position of the punch relative to the die.
10. The assembly of claim 1 wherein the arcuate die cutting edges are spaced along one side of the die and the coinciding punch cutting edges are spaced along one side of the punch facing the die.
11. The assembly of claim 1 wherein the punch has a plurality of spaced recesses, outwardly projected teeth on each side of each recess, said spaced arcuate cutting edges of the punch located between adjacent teeth, said teeth having side guide surfaces generally tangent to the radii of the arcuate cutting edges of the punch associated with adjacent teeth.
12. A punch and die assembly comprising: a die having a plurality of spaced projections along one side of the die, each projection having an arcuate cutting edge, a punch having a plurality of spaced recesses, outwardly projected teeth on each side of each recess, and arcuate cutting edges located between adjacent teeth coinciding in shape to the cutting edges of the die, said teeth having guide surfaces tangent to the radii of the arcuate cutting edges of the punch associated with adjacent teeth to locate the work piece between the cooperating cutting edges of the die and punch, and means mounting the punch and die for relative movement toward and 5 6 away from each other and locating the coinciding die References Cited and punch cutting edges in close cutting alignment. UNITED STATES PATENTS 13. The assembly of claim 12 wherein the cutting edges of the die have different radius and the cutting edges 2656'888 10/1953 q 83 620 X of the punch have radii which correspond to different 312592O 3/1964 Smlth 83 9l7 X 5 3,357,289 12/1967 Thomson 83-62Q X radii of the cutting edges of the die.
14. The assembly of claim 12 including a guide means selectively mounted on the die in a number of positions WILLIAM LAWSON Pnmary Exammer for aligning a corner of a work piece between one cut- U S Cl X R ting edge of the die and the corresponding cutting edge 10 of the punch said guide means have an edge aligned with one guide surface on one of the teeth.