Hitachi Construction Machinery Co., Ltd.

Kazuyuki Ino

Yusaku Nozawa

Kinya Takahashi

Yoshinori Takeuchi

Nobuhiko Ichiki

Hiroshi Matsuzaki

Katsumi Ueno

Hitoshi Sato

Kenichi Kimura

Wataru Ohtsu

Hitoshi Satou

A pressure selector valve () is provided between a hydraulic motor () and a directional control valve () to connect one of the main conduits (A), (B) on a high pressure side to a high pressure conduit () while connecting the other of the main conduits on a low pressure side to a low pressure conduit (). As an inertial body approaches a stop position, a spool valve () is switched to an open position (e), bringing a branch passage (A) of the high pressure conduit () into communication with the low pressure conduit. When the pressure difference between the main conduits becomes small, the pressure selector valve is automatically returned to a neutral position to cut off communication between the main conduits, suppressing a reversing movement of the hydraulic motor so that an inertial body can be brought to a stop smoothly.

Inertial body drive system

A hydraulic motor capable of minimizing a wear caused on a rotating brake disk of a brake device, wherein a rotating brake disk ( ) which forms a plurality of arc-shaped grooves ( ) apart from each other in circumferential direction and constitutes a brake device ( ) is provided on the outer peripheral side of a cylinder block ( ), and a plurality of arc-shaped projections ( ) engaged with the arc-shaped grooves ( ) and a plurality of radial contact parts ( ) are provided on the inner peripheral side of the rotating brake disk ( ) and the plurality of radial contact parts ( ) are allowed to face the outer peripheral surface of the cylinder block ( ) so that they can be brought into contact with each other, whereby, at the time of braking of the hydraulic motor ( ), the movement of the rotating brake disk ( ) in rotating direction is controlled by the arc-shaped projections ( ) and the movement of the rotating brake disk ( ) in radial direction is controlled by the radial contact parts ( ).

Hydraulic motor with brake device

Hydraulic drive system

Inertial body drive mechanism

Pressure compensating valve assembly

Growing community of inventors

Sakuragawa, Japan

Kazuyuki Ino