Shock absorber and press apparatus using the same

A shock absorber that is configured to be mounted on a press apparatus comprising:

• a lower die unit having a lower forming die and a lower blank holder;
• and an upper die unit having an upper forming die that cooperates with the lower forming die to perform press-forming on a blank and an upper blank holder that cooperates with the lower blank holder to hold the blank, the upper die unit being movable in vertical directions relative to the lower die unit, the shock absorber being utilized for absorbing impact applied to the upper blank holder by the upper forming die when opening the upper and lower forming dies, the shock absorber comprising:
• a support rod that is configured to be attached vertically to either one of the upper blank holder and the upper forming die;
• a hollow piston rod that is fixed to the support rod and through which the support rod extends;
• a case that has the hollow piston rod disposed therein such that the hollow piston rod protrudes from both ends of the case in a relaxed state of the shock absorber, the case being further provided with a die abutting surface capable of abutting on the other of the upper blank holder and the upper forming die, the case being movable relative to the hollow piston rod;
• a piston that is provided on the hollow piston rod and is movable through oil filled in the case;
• and
• a rod abutting member that is mounted on a tip end of the support rod, is configured to be positioned away from the case when the shock absorber is in the relaxed state, and is configured to abut on the case when the shock absorber is in a compressed state, the rod abutting member having an outer diameter that is greater than an outer diameter of the piston rod.

A press apparatus comprising:

• a lower die unit having a lower forming die and a lower blank holder;
• and
• an upper die unit having an upper forming die that cooperates with the lower forming die to perform press-forming on a blank and an upper blank holder that cooperates with the lower blank holder to hold the blank, the upper die unit being movable in vertical directions relative to the lower die unit,
• wherein the press apparatus further comprises:
• a side pin that is attached horizontally to either one of the upper blank holder or the upper forming die, and protruding into a guide groove formed on the other of the upper blank holder or the upper forming die;
• and
• a shock absorber that is attached to the guide groove, and abutting on the side pin when the upper die unit is moved upward away from the lower die unit to open the upper and lower forming dies after press-forming is performed on the blank so that impact applied to the upper blank holder by the upper forming die when opening the upper and lower forming dies is absorbed.

A press apparatus comprising:

• a lower die unit having a lower forming die and a lower blank holder;
• and an upper die unit having an upper forming die that cooperates with the lower forming die to perform press-forming on a blank and an upper blank holder that cooperates with the lower blank holder to hold the blank, the upper die unit being movable in vertical directions relative to the lower die unit;
• wherein the press apparatus further comprises:
• a support rod that is attached vertically to either one of the upper blank holder and the upper forming die;
• and
• a shock absorber that is mounted on the support rod, and absorbing impact applied to the upper blank holder by the upper forming die when the upper die unit is moved upward away from the lower die unit to open the upper and lower forming dies after press-forming is performed on the blank,
• wherein the shock absorber has:
• a hollow piston rod that is fixed to the support rod and through which the support rod extends;
• a case that has the hollow piston rod disposed therein such that the hollow piston rod protrudes from both ends of the case in a relaxed state of the shock absorber, the case being further provided with a die abutting surface capable of abutting on the other of the upper blank holder and the upper forming die, the case being movable relative to the hollow piston rod;
• and
• a piston that is provided on the hollow piston rod and is movable through oil filled in the case.

A press apparatus comprising:

• a lower die unit having a lower forming die and a lower blank holder;
• and
• an upper die unit having an upper forming die that cooperates with the lower forming die to perform press-forming on a blank and an upper blank holder that cooperates with the lower blank holder to hold the blank, the upper die unit being movable in vertical directions relative to the lower die unit,
• wherein the press apparatus further comprises:
• a support rod that is attached vertically to the lower forming die;
• and
• a shock absorber that is mounted on the support rod, and absorbing impact applied to the lower forming die by the lower blank holder when the upper die unit is moved upward away from the lower die unit to open the upper and lower forming dies after press-forming is performed on the blank,
• wherein the shock absorber has:
• a hollow piston rod that is fixed to the support rod and through which the support rod extends;
• a case that has the hollow piston rod disposed therein such that the hollow piston rod protrudes from both ends of the case in a relaxed state of the shock absorber, the case being further provided with a die abutting surface capable of abutting on the lower blank holder, the case being movable relative to the hollow piston rod;
• and
• a piston that is provided on the hollow piston rod and is movable through oil filled in the case.