System and method of forming hole in blank during hydroforming process
AssigneeCaterpillar Inc.
InventorsScott A. Christianson, Mark W. Hammerton, Murray R. Mason
Life of this patent
Estimating the term…
Abstract
A method of forming a hole in a hollow blank during a hydroforming process is provided. The method includes placing a blank in a cavity of a hydroforming die, the hydroforming die being configured to permit a punch to engage the blank. An interior of the blank is pressurized with a fluid. Further, a cutting end of a punch is applied through a wall portion of the blank and into the interior of the blank to form a hole. Furthermore, the cutting end of the punch is removed from the interior of the blank such that the cutting end of the punch is configured to allow material of the blank surrounding the formed hole to move away from the interior of the blank.
Claims19
A method of forming holes in a hollow blank during a hydroforming process, the method comprising:
- placing a blank in a cavity of a hydroforming die, the hydroforming die being configured to permit a punch to engage the blank;
- maintaining a gap between the blank and a portion of the hydroforming die including the cavity;
- pressurizing an interior of the blank with fluid;
- deforming a portion of the blank into the gap and towards the cavity prior to an engagement of the punch with the blank, the portion of the blank corresponding to a path of the punch;
- applying a cutting end of the punch through a wall portion of the blank and into the interior of the blank to form a hole;
- and
- removing the cutting end of the punch from the interior of the blank,
- wherein the cutting end of the punch is configured to allow material of the blank surrounding the hole to move away from the interior of the blank.
A method of piercing holes in a wall of a tube during a hydroforming process, the method comprising:
- placing a blank in a cavity of a hydroforming die, the hydroforming die being configured to permit a punch to engage the blank;
- maintaining a gap between the blank and a portion of the hydroforming die including the cavity;
- pressurizing an interior of the blank with fluid;
- deforming a portion of the blank from an original position of a material of the blank into the gap and towards the cavity prior to an engagement of the punch with the blank, the portion of the blank corresponding to a path of the punch;
- applying a cutting end of the punch through a wall portion of the blank and into the interior of the blank to form a hole, a portion of the cutting end of the punch having a groove circumferentially disposed about the punch, material surrounding the hole being displaced from the original position of the material of the blank by an initial displacement and then allowed to be displaced within the groove to an intermediate displacement closer to the original position of the material of the blank;
- and
- removing the cutting end of the punch from the interior of the blank, wherein a first surface forming the groove is capable of engaging the material surrounding the hole away from the intermediate displacement to a final displacement.
A punch for piercing a hole in a blank during a hydroforming process, the punch comprising:
- a shank portion;
- a cutting end provided on the shank portion and configured to form a hole in the blank;
- and
- a reduced cross-sectional area disposed about an outer surface of the punch and adjacent to the cutting end, the reduced cross-sectional area is configured to allow material of the blank surrounding the hole to move away from the interior of the blank,
- wherein a cross-sectional area of the cutting end increases about a longitudinal axis of the punch from an axial end of the shank to a first end of the reduced cross-sectional area that is adjacent to the cutting end,
- wherein a cross-sectional area of a second end of the reduced cross-sectional area increases about the longitudinal axis of the punch from an end of a portion of the reduced cross-section area that is positioned between the first end and the second end and has a cross-sectional area less than the cross-sectional area of the cutting end.
Dependencies are inferred from the claim text.