US 9,808,848 B2
Die cushion apparatus of press machine and die cushion controlling method
Yasuyuki Kohno, Sagamihara (JP); Tadahiro Kondo, Sagamihara (JP); and Ryosho Iwamura, Sagamihara (JP)
Assigned to AIDA ENGINEERING, LTD., Kanagawa (JP)
Filed by AIDA ENGINEERING, LTD., Sagamihara-shi, Kanagawa (JP)
Filed on Jan. 23, 2014, as Appl. No. 14/162,377.
Claims priority of application No. 2013-011043 (JP), filed on Jan. 24, 2013.
Prior Publication US 2014/0202223 A1, Jul. 24, 2014
Int. Cl. B21D 24/02 (2006.01); B30B 15/24 (2006.01); B21D 24/14 (2006.01)
CPC B21D 24/02 (2013.01) [B21D 24/14 (2013.01); B30B 15/24 (2013.01)] 5 Claims
OG exemplary drawing
 
1. has been replaced with the following:
A die cushion apparatus of a press machine comprising:
a cushion pad supporting a plane face of the cushion pad comprised of cushion pins supporting blank holding plates for holding a material to be formed within a space proximal to a respective set of die including a lower die, in parallel to the lower faces of an upper die affixed to a plane face of the slide;
multiple cushion pad raising and lowering devices configured to raise and lower the cushion pad by separately-controllable multiple driving shafts;
a die cushion position instruction generating unit configured to output multiple position instruction values, each of which individually instructs a position in a raising and lowering direction of the cushion pad corresponding to a position of each driving shaft of the multiple cushion pad raising and lowering devices, the die cushion position instruction generating unit including multiple standby position instruction values for at least holding the cushion pad at a standby position, the multiple standby position instruction values being separate from each other, and outputting the multiple standby position instruction values after knocking out a product;
multiple die cushion position detecting devices configured to detect the position in the raising and lowering direction of the cushion pad corresponding to the position for each driving shaft of the multiple cushion pad raising and lowering devices, and separately output position detection values indicating the detected positions;
an information acquiring device configured to acquire information regarding inclination of the cushion pad in a duration of die cushion force control based on the position detection values outputted from the multiple die cushion position detecting devices; and
a controlling device configured to separately control the multiple cushion pad raising and lowering devices based on the multiple position instruction values outputted from the die cushion position instruction generating unit, and on the multiple position detection values outputted from the multiple die cushion position detecting devices, the controlling device configured to move the cushion pad to the standby position based on the multiple standby position instruction values outputted from the die cushion position instruction generating unit after knocking out the product,
wherein the multiple standby position instruction values are individually adjusted based on the information acquired from the information acquiring device to allow the cushion pad to be held, before applying die cushion force control, on standby holding the material in parallel with lower faces of dies mounted to the slide of the press machine in an inclined state of the dies with respect to the plane face of the slide of the press machine.