To provide a valve assembly that balances fluid pressures on both sides of a valve completely or partially, and reduces valve operation force so that an electric operation type can be applicable.
The valve assembly body includes a valve housing comprising a valve chamber, a channel, and a piston chamber. The valve member is arranged in a valve housing and can travel along a valve axis. The valve member receives the first pressure, which energizes the valve in a first direction. For canceling the force, a piston in one piece with the valve member is slidably arranged in the piston chamber. One side of the piston receives the first pressure, and supplies cancellation force. A pressure passage provides the fluid communication of the first pressure between the channel and one side of the piston.
Tadao Naito
Kiyoshi Miyakawa
Hiroyuki Matsumura
Hirofumi Higashino
Shigeo Shibata