US3566665A

US3566665A - Sheet metal forming press for forming flattened horns on the edges of sheet metal blanks

Info

Publication number: US3566665A
Application number: US721467A
Authority: US
Inventors: Joseph Birrer
Original assignee: Haemmerle AG Maschinenfabrik
Current assignee: Haemmerle AG Maschinenfabrik
Priority date: 1967-04-21
Filing date: 1968-04-15
Publication date: 1971-03-02
Anticipated expiration: 1988-03-02
Also published as: CH462757A; SE331829B; GB1165305A; AT268007B; FR1561658A; DE1752183A1

Abstract

THE DISCLOSURE PROVIDES A SHEET METAL FORMING PRESS FOR FORMING FLATTENED HORNS ON THE EDGES OF SHEET METAL BLANKS WHICH COMPRISES A BOLSTER MOUNTED BETWEEN CENTERING SPRINGS PERMITTING THE BOLSTER TO YIELD IN A DIRECTION NORMAL TO THE DIRECTION OF PRESSING, A VERTICALLY MOVABLE DIE ADAPTED TO BE LIFTED OFF AND LOWERED ONTO SAID BOLSTER, AND A VERTICALLY MOVABLE FORMING PUNCH COOPERATING WITH SAID DIE, THE ARRANGEMENT BEING SUCH THAT THE SHEET METAL BLANK IS OPTIONALLY INTERPOSABLE BETWEEN THE FORMING PUNCH AND THE DIE OR BETWEEN THE UNDERSIDE OF THE DIE AND THE BOLSTER.

Description

March 2, 1971 J. BIRRER 3,566,665

SHEET METAL FORMING PRESS FOR FORMING FLATTENED HORNS ON THE EDGES OF SHEET METAL BLANKS Filed April 15, 1968 3 Sheets-Sheet 1 N E? U- E? d Ll- ::l I

I q- INVENTOR JOSEPH B'RRER 1 Han/w 0. g

ATTORNEY March 2, 1971 BIRRER 3,566,665

SHEET ME FORMING PRESS FOR FORMING FLA NED norms.

THE EDGES 0F SHEET METAL BLA s Filed April 15. 1968 5 Sheets-Sheet I I MH March 2, 1971 J. BIRRER 3,566,665

SHEET ME FORMING PRESS FOR FORM FLATTENED HORNS THE EDGES OF SHEET MET BLANKS Filed April 15, 1968 v s Sheets-Sheet s 5 IHWHIIP l7 fi/ W I I9 K United States Patent O SHEET METAL FORMING PRESS FOR FORMING FLATTENED HORNS ON THE EDGES F SHEET METAL BLANKS Joseph Birrer, Zofingen, Switzerland, assignor to Hammerle A.G., Zofingen, Switzerland Filed Apr. 15, 1968, Ser. No. 721,467 Claims priority, application Austria, Apr. 21, 1967, A 3,776/ 67 Int. Cl. B211 13/ 02 US. Cl. 72-404 2 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION This invention relates to a sheet metal forming press for forming flattened horns on the edges of sheet metal blanks.

SUMMARY OF THE INVENTION It is the object of the invention to provide a sheet metal forming press for horning the edges of sheet metal blanks and flattening the horns in two operations without the necessity of resetting the tools of the press.

To attain this object the present invention provides a sheet metal forming press for forming flattened horns on the edges of sheet metal blanks, which comprises a bolster mounted between centering springs permitting the bolster to yield in a direction normal to the direction of pressing; a vertically movable die adapted to be lifted oif and lowered onto said bolster, and a vertically movable forming punch cooperating with said die.

The die may be vertically movably mounted near each of its ends between lateral guideways and associated with rams for optionally lifting the die off the bolster or lowerin g the die onto the bolster.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings in which:

FIG. 1 is a schematic representation of an arrangement proposed by the invention whilst performing a first operation;

FIG. 2 is a similar view showing the same arrangement whilst performing a second operation;

FIG. 3 is a front elevation of the arrangement;

FIG. 4 is a vertical section of the arrangement according to FIG. 3, and

FIG. 5 is a vertical section of a modified arrangement according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The principle of operation of a press according to the invention will first be described 'with reference to FIGS. 1 and 2. The press comprises a baseplate 1 which is pro- 3,566,665 Patented Mar. 2, 1971 vided with a recess 2 for the reception therein of a bolster 3. The bolster 3 is horizontally movable in the recess 2 but is urged into central position in the recess 2 by centering springs 4. Above the bolster 3 a die 5 is vertically movably mounted and can be lowered to rest on the bolster 3. A V-slot 6 in the upper surface of the die 5 serves for forming a horn on the edge of a sheet metal blank. For this purpose the die 5 cooperates with a forming punch 7. FIG. 1 shows the forming punch 7 having descended into the V-slot 6 to form a horn on the edge of a sheet metal blank 8.

When the forming punch 7 has been raised and the sheet metal blank 8 removed from the V-slot 6 the die 5 is lifted off the bolster 3 and the horned edge of the sheet metal blank 8 is placed on the bolster 3 with the horn pointing upwards, the free edge 9 of the horn engaging the underside 10 of the die 5. The underside 10 of the die 5 now functions as a pressplate when the forming punch 7 de cends into the empty V-slot 6 and thus forces the die 5 downwards onto the bolster 3. The bolster 3 yields laterally to the right in FIG. 2 and thus permits the horn to be flattened down on the surface of the sheet metal blank 8. If the bolster 3 were unable laterally to yield, the horn could not be pressed flat because the upper edge9 of the horn catches on the underside 10 of the die 5 whereas it should be free to describe an are 11 of a circle whilst being pressed onto the surface of the sheet metal blank 8. A rigidly fixed bolster 3 would have the effect of subjecting the die 5, which is guided exclusively at its two ends, to such considerable lateral strain that in practice the horn could not be properly closed. However, the ability of the bolster 3 to yield by compressing the centering spring 4 permits the horn to be flattened down against the surface of the sheet metal blank 8 without the application of unduly high pressure.

Practical embodiments of the press proposed by the invention are illustratively shown in FIGS. 3, 4 and 5. A baseplate, which in these drawings is indicated by the reference numeral 12, carries a bolster 13 which is horizontally movable between centering springs 14 provided for holding the bolster 13 in the illustrated central position. A die 15 is vertically movably mounted in laterally spaced guideways provided in portal-shaped supports 16 near each end of the die 15. The ends of the die 15 projecting from the guiding supports rest on the rams 17 of two pneumatically operable ram cylinders 18 (FIGS. 3 and 4) which may stand on the base or on separate foundations on the floor (FIG. 5). Compressed air can be admitted into each cylinder 18 through an opening 19. Each ram 17 has a spherical head 20 which bears against a cooperating socket-shaped surface in the end of the die 15. A forming punch 22 is adapted to descend into the V-slot 21 of the die 15 from above. The forming punch 22 is slidably mounted in ways not shown in the drawings and can be lowered and raised by conventional means.

The described arrangement permits sheet metal blanks to be provided with flattened horns in two operations without the need of remounting or changing the tools. The proposed machine therefore saves labour and time.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed is:

1. A sheet metal forming press for forming flattened horns on the edges of sheet metal blanks, comprising:

(a) a bolster mounted between centering springs permitting the bolster to yield in a direction normal to the direction of pressing;

(b) a vertically movable die adapted to be lifted off and lowered onto said bolster, and

(c) a vertically movable forming punch cooperating with said die, said press adapted to receive a sheet metal blank between the forming punch and the die or between the underside of the die and the bolster.

2. A sheet metal forming press according to claim 1, wherein the die is vertically movably mounted near each of its ends between laterally spaced guideways and associated with ra-ms for optionally lifting the die oh. the bolster 0r lowering the die onto the bolster.

References Cited UNITED STATES PATENTS 970,952 9/1910 Rice 72-404 1,173,168 2/1916 Burditt 72-404 5 1,173,169 2/1916 Burditt 72-404 2,245,642 6/1941 Bell 72-447 CHARLES W. LANHAM, Primary Examiner 10 G. P. CROSBY, Assistant Examiner U.S. Cl. X.'R. 72--447, 462