Blank holder device

Claim 2

In an apparatus for forming deep drawn seamless metal can bodies provided with a bottom and sidewall formed integrally therewith the combination or a redraw and ironing die means, a forming punch movable into and out of said die means and operable to force a metal cup-shaped workpiece through said die means during the forward stroke of the punch so as to draw and iron the cup-shaped metal workpiece, means for operating said punch, a fluid operated cup holder sleeve device telescopically arranged relative to said punch and operable and movable independently of the punch relative to said die means, said sleeve device including a piston section and a uniform pressure applying nose section removably secured to said piston section, the sleeve device being adapted to move forward toward the die means slightly in advance of the punch and to engage and press a cupshaped workpiece against the redraw portion of said die means and to effect a centering of the cup-shaped workpiece relative to the axis of the die means and the punch until and as the punch displaces the cup-shaped workpiece from the sleeve device and carries the cup-shaped workpiece into the redraw portion of the die means, a plurality of bolt elements for removably locking the nose section of the sleeve device to said piston section, a cotter pin-like lock means for said bolt elements for preventing the turning of the bolt elements and an unlocking of the nose section from the piston section during operation of the sleeve device and said piston section having an elongated skirt element for axially supporting and guiding said nose section relative to a workpiece.

Claim 3

The apparatus as set forth in claim 1 including low pressure compressed air means for operating said sleeve device.

Claim 4

The apparatus as set forth in claim 1 wherein the nose section is made from heat treatable steel of greater Rockwell hardness than the piston section.

Claim 5

The apparatus as set forth in claim 1, wherein said cotter pin-like means comprises a single relatively stiff wire threaded through all of the bolt elements.

Claim 6

The apparatus as set forth in claim 1 wherein the piston section is provided with a combination self-lubricating seal and bearing means.

Claim 7

In an apparatus for forming deep drawn seamless metal can bodies provided with a bottom and a sidewall formed integrally therewith the combination of a redraw and ironing die means, a forming puNch movable in a single continuous stroke into and through said die means so as to draw and iron a cup-shaped metal workpiece, means for actuating said punch, a fluid operated cup holder sleeve device telescopingly arranged relative to said punch and operable and movable independently of the punch relative to said die means, said sleeve device including a piston section and a uniform pressure applying nose section removably secured to said piston section, the sleeve device being adapted to move forward toward the die means slightly in advance of the punch means and to engage and press a cup-shaped metal workpiece against the initial and redraw portion of the die means and to effect a centering of the cup-shaped workpiece relative to the axis of the die means and the punch until and as the punch displaces the cup-shaped workpiece from the sleeve device and carries the cup-shaped workpiece into the redraw portion of the die means, a plurality of bolt elements for removably locking the nose section of the sleeve device to said piston section, each of said bolt elements having a cross bore therein and a common stiff wire element threaded through said bores in cotter pin fashion so as to prevent the turning of the bolt elements and an unlocking of the nose section from the piston section during operation of the sleeve device and said piston section having an elongated skirt element for axially supporting and guiding said nose section relative to said cup-shaped workpiece.

Claim 8

In an apparatus for forming deep drawn seamless metal can bodies provided with a bottom and a sidewall formed integrally therewith the combination of a redraw and ironing die means, a forming puNch movable in a single continuous stroke into and through said die means so as to draw and iron a cup-shaped metal workpiece, means for actuating said punch, a fluid operated cup holder sleeve device telescopingly arranged relative to said punch and operable and movable independently of the punch relative to said die means, said sleeve device including a piston section and a uniform pressure applying nose section removably secured to said piston section, the sleeve device being adapted to move forward toward the die means slightly in advance of the punch means and to engage and press a cup-shaped metal workpiece against the initial and redraw portion of the die means and to effect a centering of the cup-shaped workpiece relative to the axis of the die means and the punch until and as the punch displaces the cup-shaped workpiece from the sleeve device and carries the cup-shaped workpiece into the redraw portion of the die means, a plurality of bolt elements for removably locking the nose section of the sleeve device to said piston section, each of said bolt elements having a cross bore therein and a common stiff wire element threaded through said bores in cotter pin fashion so as to prevent the turning of the bolt elements and an unlocking of the nose section from the piston section during operation of the sleeve device and said piston section having an elongated skirt element for axially supporting and guiding said nose section relative to said cup-shaped workpiece.

Claim 9

The apparatus as set forth in claim 6 including a combination self-lubricating seal and bearing means for the piston section of said sleeve device.

Claim 10

The apparatus of claim 6 including means for synchronizing the movements of said punch and said sleeve device.

Claim 11

The apparatus as set forth in claim 6 including low pressure compressed air means for operating said sleeve device.

Claim 12

An apparatus as set forth in claim 2 wherein said compressed air means includes a lubricating oil reservoir connected to the air source line whereby lubricating oil for said sleeve device can be entrained in the air used to actuate and which contacts the sleeve device.

Claim 13

An apparatus as set forth in claim 9 wherein said compressed air means includes a lubricating oil reservoir connected to the air source line whereby lubricating oil for said sleeve device can be entrained in the air used to actuate and which contacts the sleeve device.