Title:
液圧式ロータリー衝撃ハンマードリル
Document Type and Number:
Japanese Patent JP2005527388
Kind Code:
A
Abstract:
The hammer drill (1) comprises a body (2) containing an alternating impact piston (4) which slides under the effect of a main hydraulic supply circuit (22). The circuit also causes an annular stop piston (5) to slide in a body cavity (3). The stop piston comprises a front face, in contact with an insert (7), which positions the insert at a pre-determined distance from the impact piston. When the main circuit is stopped, an external hydraulic supply circuit (23) can introduce pressurized fluid between the stop piston rear face and the cavity rear wall so as to maintain a space between them.
Inventors:
Jean-Sylvain Comalmont
Application Number:
JP2003576150A
Publication Date:
September 15, 2005
Filing Date:
March 18, 2003
Export Citation:
Assignee:
Montabert Societe Anonymous
International Classes:
B25D9/12; B25D16/00; B25D17/24; E21B6/00; (IPC1-7): B25D16/00
Attorney, Agent or Firm:
Masatake Shiga
Takashi Watanabe
Masakazu Aoyama
Yasuhiko Murayama
Shinya Mitsuhiro
Takashi Watanabe
Masakazu Aoyama
Yasuhiko Murayama
Shinya Mitsuhiro