| 摘要 |
<p>A combined load-sensing proportion and relay valve comprising a valve disk having an exhaust passage in the axial center and held in a normally closed-valve condition, and a control piston assembly for adjustably moving the valve disk to open the valve, characterized in that the control piston assembly consists of three pressure-sensitive pistons, the third piston being formed in one piece with the first piston, the first piston having a downward projection extended from its underside, with the lower end of the projection serving as a valve seat opposite to and engageable with the valve disk, a load spring is disposed between the second and third pressure-sensitive pistons, a regulated-pressure controller consisting of a regulated-pressure exhaust valve held in a normally-open condition and an indicated-pressure feed valve held in a normally closed condition is located with a part of the second pressure-sensitive piston serving as its valve seat, an indicated-pressure chamber is formed above the second piston, and a regulated-pressure chamber is formed between the underside of the second piston and the upper side of the third piston, the regulated-pressure exhaust valve that governs the opening and closing of the indicated-pressure feed valve and the exhausting of the regulated-pressure being located in such a manner that its position is adjustable according to the payload of the vehicle equipped with the relay valve.</p> |
