Title:
SAFETY DEVICE FOR MACHINE TOOL AND MACHINE TOOL WITH THE SAME
Document Type and Number:
WIPO Patent Application WO/2005/097405
Kind Code:
A1
Abstract:
[PROBLEMS] A safety device for a machine tool, which alone functions as both as means for balancing the weight of a rising/lowering member and as cushioning means for preventing falling and sudden rise of the rising/lowering member. [MEANS FOR SOLVING PROBLEMS] A safety device for a machine tool, having an air cylinder (151) that is provided above or below a rising-lowering member (7) and whose advanceable retreatable piston rod (152a) is connected to the lifting/lowering member (7), a piston (152) that is provided inside the air cylinder (151), a first chamber (151a) and a second chamber that are partitioned by the piston (152), first pressure holding means (155, 156) for maintaining the pressure in the first chamber (151a) constant at all times, an solenoid valve (153) that is provided between the first pressure holding means (155, 156) and the first chamber (151a) and that restricts the flow of fluid when power shutoff etc. occurs, and second pressure holding means for holding the pressure of the second chamber (151b) at a constant pressure different from the pressure of the fluid in the first pressure chamber (151a).
Inventors:
SOMEYA EIICHIRO (JP)
MAEHARA TOMONORI (JP)
MAEHARA TOMONORI (JP)
Application Number:
PCT/JP2005/005389
Publication Date:
October 20, 2005
Filing Date:
March 24, 2005
Export Citation:
Assignee:
CITIZEN WATCH CO LTD (JP)
SOMEYA EIICHIRO (JP)
MAEHARA TOMONORI (JP)
SOMEYA EIICHIRO (JP)
MAEHARA TOMONORI (JP)
International Classes:
B23Q5/28; B23Q5/58; B23Q11/00; F15B20/00; (IPC1-7): B23Q5/58; B23Q5/28; B23Q11/00
Foreign References:
| JP2001136726A | 2001-05-18 | |||
| JP8029446B2 | ||||
| JPH0810961A | 1996-01-16 | |||
| US5303549A | 1994-04-19 |
Attorney, Agent or Firm:
Watanabe, Kihei (26 Kanda Suda-cho 1-chom, Chiyoda-ku Tokyo 41, JP)
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