Patent ID: 7387136
Filing Date: 2008-06-17
Classification: F02M,F04B,G05D,Y10T

Abstract:
1. A regulation valve to regulate a pressure of a fuel comprising: a cylinder that has an inlet port at one end side thereof to introduce the fuel thereinto, and a relief port opening on a side face thereof; a piston that is reciprocatably inserted in the cylinder to vary an opening area of the relief port in accordance with a variation of the pressure of the fuel flowing in through the inlet port; and an urging means that urges the piston in a direction against the pressure of the fuel acting on the piston to regulate the pressure to be a specific value, wherein at least one of the cylinder and the piston is formed so that the piston opens the relief port at a first speed per a unit displacement thereof at a first stage to start opening the relief port and at a second speed larger than the first speed at a second stage subsequent to the first stage, wherein a stroke of the piston includes: wherein the relief port includes a first relief port and a second relief port that are displaced from each other in a longitudinal direction of the cylinder, wherein the first relief port and the second relief port are separately formed and disposed to overlap each other in the longitudinal direction of the cylinder, wherein the second relief port is disposed in the first opening region, and the first relief port is disposed in the second opening region, and wherein the first relief port includes a plurality of holes, which are arranged along a circumferential direction of the cylinder.