Abstract 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 regulatedpressure 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.
A combined load-sensing proportion and relay valve comprising a valve disk having a central axis with an exhaust passage on the central axis and held in a normally closed-valve condition, and a control piston assembly for adjustably moving the valve disk to open the valve disk, 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, said 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 pressuresensitive 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 pressuresensitive piston serving as its valve seat, an indicated-pressure chamber is formed above the second piston, and a regulatedpressure chamber is formed between the underside of the second piston and the upper side of the third piston, said regulatedpressure 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.
Claim 2
Dependent Claim
227 words
A combined load-sensing proportion and relay valve comprising a valve disk having a central axis with an exhaust passage on the central axis and held in a normally closed-valve condition, and a control piston assembly for adjustably moving the valve disk to open the valve disk, 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, said 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 pressuresensitive 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 pressuresensitive piston serving as its valve seat, an indicated-pressure chamber is formed above the second piston, and a regulatedpressure chamber is formed between the underside of the second piston and the upper side of the third piston, said regulatedpressure 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.
Claim 3
Dependent Claim
23 words
A valve as claimed in claim 1 wherein the second pressure-sensitive piston has a pressure-receiving area larger than that of the third piston.
Claim 4
Dependent Claim
40 words
A valve as claimed in claim 1 wherein the regulated-pressure exhaust valve of the regulated-pressure controller is connected to a stroke adjuster, which in turn is connected to the lower part of a suspension spring or springs through connecting means.
Claim 5
Dependent Claim
46 words
A valve as claimed in claim 3 wherein the stroke adjuster is turnably supported by a pivot pin, and the regulated-pressure exhaust valve is turnably supported by a pivot pin and biased toward the direction where it opens by a spring located round the pivot pin.