Claims
- 1. In a deep draw punch assembly having a punch member for deep drawing cans, a tooling set for holding the blank and including a drawing die for operation in conjunction with said punch, said tooling set including blank cutting means, and a cutting ring and draw pad cooperating with said tooling set, the improvement comprising fluid pressure cylinder means for operating said cutting ring and for regulating the pressure of said draw pad acting against said blank during a drawing operation including a tubular cylindrical member surrounding said punch, and including means forming a pair of fluid pressure cylinders relative to a piston portion of said cylindrical member to provide a double acting fluid pressure actuator, said cutting ring being fixedly mounted to said cylindrical member at the lower edge thereof, said cutting ring being moved during actuation of said cylinder means from a position wherein it cooperates with said blank cutting means to cut a blank from a piece of material supported on said tooling set to a position raised from said tooling set, said draw pad comprising an annular pad member supported relative to said cutting ring for movement by said cutting ring during retraction of said cutting ring away from said tooling set, and means to exert a pressure from said tubular cylinder member on said draw pad member during a drawing operation including means fixedly mounted to the lower end of said cylindrical member and forming an annular chamber of a predetermined size, an elastomeric material confined in and engaging the walls defining said chamber, and means between said draw pad and said elastomeric material to exert compressive pressures on said draw pad through said elastomeric material only upon actuation of said fluid pressure cylinder means.
- 2. The combination as specified in claim 1 wherein said elastomeric material is selected to provide a very stiff axial force generally parallel to the direction of movement of said cylinder and said draw pad, and being of low shear modulus to thereby flow during eccentric loads about a transverse axis.
- 3. The combination as specified in claim 1 wherein said means between the elastomeric material and said draw pad comprises an annular ring mounted between said elastomeric material and said draw pad and forming a piston member closely fitting within the annular chamber.
- 4. The combination as specified in claim 1 and servo control means for regulating the pressure exerted by said fluid pressure cylinder, and to provide for retraction of said fluid pressure cylinder at a preselected time.
- 5. The combination as specified in claim 1 and means defining a space overlying said draw pad, which is sufficiently closed to be pressurized at a desired pneumatic pressure, and means to supply a regulated fluid under pressure to said space.
- 6. For use in combination with a deep draw punch movable along a generally central axis and means to exert a hold down force on a blank to be formed by the punch, a low friction swivel connection between said means to exert a hold down force and a reaction member comprising a die set for deep drawing a blank in cooperation with said deep draw punch, the improvement comprising means forming an annular chamber generally centered along said central axis and surrounding the deep draw punch, and carrying the forces from the means to apply a hold down force, a movable wall forming one wall defining said chamber, a filling of elastomeric material forming an annular ring to substantially fill a confined space in said chamber, said movable wall lying generally transverse to said central axis and bearing against said elastomeric material in a position to carry load exerted by said means forming a chamber generally in direction along said axis to said elastomeric material, a draw pad member positioned between said movable wall and a blank to be formed on said die set, said elastomeric material comprising an intermediate member for carrying the force from said means to exert a force to said draw pad member, said elastomeric material flowing upon a nonsymmetrical load relative to the central axis being applied to said movable wall to tend to equalize pressure on said elastomeric material at opposite sides of said chamber, said elastomeric material transmitting loads to said movable wall without substantial compression of the elastomeric material.
- 7. In a deep draw punch assembly having a punch member for deep drawing metal blanks, a tooling set for holding the blank and including a drawing die for operation in conjunction with said punch, said tooling set including blank cutting means, and a cutting ring and draw pad cooperating with said tooling set, the improvement comprising double acting fluid pressure cylinder means for operating said cutting ring and for regulating the pressure of said draw pad acting against said blank during a drawing operation, means to fixedly mount said cutting ring to said fluid pressure cylinder means whereby said cutting ring is moved during an actuation stroke of said cylinder means to a position wherein it cooperates with said blank cutting means to cut a blank from a piece of material supported on said tooling set to a position raised from said tooling set, an annular mounting ring fixedly mounted to the fluid pressure cylinder means having walls forming an annular chamber of a predetermined size and enclosed except for an opening facing said draw pad, an elastomeric material confined in and engaging the walls defining said chamber, and means between said elastomeric material and draw pad to carry compressive forces between said fluid pressure cylinder means and said draw pad only through said elastomeric material upon actuation of said fluid pressure cylinder means.
Parent Case Info
This is a division of application Ser. No. 941,387, filed Sept. 12, 1978, now U.S. Pat. No. 4,248,545.
US Referenced Citations (18)
Foreign Referenced Citations (4)
Number |
Date |
Country |
887792 |
Aug 1953 |
DEX |
405589 |
Jan 1946 |
ITX |
586751 |
Jan 1978 |
SUX |
700260 |
Dec 1979 |
SUX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
941387 |
Sep 1978 |
|