Global Patent Index - EP 3845324 A4

EP 3845324 A4 20211020 - DIE CUSHION DEVICE

Title (en)

DIE CUSHION DEVICE

Title (de)

STEMPELKISSENVORRICHTUNG

Title (fr)

COUSSIN

Publication

EP 3845324 A4 20211020 (EN)

Application

EP 19854535 A 20190823

Priority

  • JP 2018162953 A 20180831
  • JP 2019077026 A 20190415
  • JP 2019033114 W 20190823

Abstract (en)

[origin: EP3845324A1] A die cushion device includes: a hydraulic cylinder (10) that vertically moves a cushion pad (14); a hydraulic pump (P) that supplies hydraulic oil from an oil tank (T) to the hydraulic cylinder (10); a relief valve (20) that returns hydraulic oil discharged from the hydraulic cylinder (10), to the oil tank (T); a pressure sensor (PS) that detects a hydraulic oil pressure, which is a die cushion pressure of the hydraulic cylinder (10); and a control device (40) that controls a flow rate and a pressure of hydraulic oil supplied from the hydraulic pump (P) to the hydraulic cylinder (10). The control device controls the number of rotations of the hydraulic pump (P) such that the hydraulic oil pressure detected by the pressure sensor (PS) reaches a die cushion pressure command value, and when a hydraulic oil pressure detected by the pressure sensor is equal to or higher than a set pressure of the relief valve (20), the control device (40) reversely rotates the hydraulic pump (P).

IPC 8 full level

B21D 24/02 (2006.01); B21D 24/14 (2006.01); B30B 15/02 (2006.01); F15B 11/16 (2006.01)

CPC (source: EP)

B21D 24/14 (2013.01); B30B 15/16 (2013.01); B30B 15/26 (2013.01)

Citation (search report)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

DOCDB simple family (publication)

EP 3845324 A1 20210707; EP 3845324 A4 20211020; EP 3845324 B1 20230308; JP 2020171959 A 20201022; JP 6702491 B1 20200603; WO 2020045300 A1 20200305

DOCDB simple family (application)

EP 19854535 A 20190823; JP 2019033114 W 20190823; JP 2019151783 A 20190822