JPH01171769U - - Google Patents

Description

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the master cylinder according to the present invention, Fig. 2 is an enlarged view of the main parts in Fig. 1, and Fig. 3 is a modification of the master cylinder according to the present invention. The vertical sectional view shown in FIG. 4 is an enlarged view of the main part in FIG. 3. 10... Master cylinder, 11... Cylinder body, 11a... Inner hole, 12... Primary piston, 13... Piston part, 13c... Stepped inner hole, 13d... Small diameter hole, 13e... Throttle hole, 13f
...Radial hole, 13g...Through hole, 13h...Large diameter hole, 14...Piston piece, 16...Return spring, 18a, 19a...Primary cup, 18b, 19b...Secondary cup, 2
0...Stoppa pin, 21...Stoppa bolt,
23... Valve rod, 24... Valve body, 26...
Spring, 27...retainer, 28...spring, V1...valve mechanism.

Claims (1)

[Scope of utility model registration request] A pressure chamber and a reservoir that are fluid-tightly and slidably inserted in the axial direction via a piston cup into the inner hole of the cylinder body that accommodates the hydraulic fluid are constantly connected to the hydraulic pressure pipe in the same inner hole. a piston that forms a communicating replenishment chamber and has a communication hole that communicates the pressure chamber and the replenishment chamber; and a biasing means that is accommodated in the pressure chamber and biases the piston toward a non-operating position. , is attached to the tip of the piston to allow communication between the pressure chamber and the supply chamber through the communication hole when the piston is in the non-operating position, and the piston is moved by a predetermined amount or more from the non-operating position. a valve mechanism that shuts off communication between the pressure chamber and the replenishment chamber when the piston moves from the non-operating position by a predetermined amount or more; is sealed so that hydraulic pressure is generated in the pressure chamber, and hydraulic fluid can flow from the supply chamber to the pressure chamber through the piston cup when the piston moves from the moving position to the non-actuating position. In the master cylinder, the piston has a stepped inner hole having a larger diameter on the pressure chamber side where the valve mechanism is attached to the axis of the piston, and a stepped inner hole in the center thereof with one end opening to the supply chamber and the other end opening to the supply chamber. a piston portion having a radial hole that opens through a throttle hole in a small diameter portion of a stepped inner hole; and a through hole that radially penetrates the small diameter portion and has both ends open to the pressure chamber; It is constituted by a cylindrical piston piece, on which the piston cup is fitted on the outer periphery of the piston portion, and which is slidably fitted in a fluid-tight manner onto the outer periphery of the piston portion, and which is urged toward the supply chamber by the urging means. and a stopper pin that loosely fits the valve mechanism into the through hole, has both ends fixed to the piston piece, and connects the piston piece and the piston portion so as to be movable relative to each other by a predetermined amount; A valve rod capable of seating on a valve seat formed in a stepped portion is fitted onto its outer periphery, and one end of the valve rod is loosely fitted into a small diameter hole of the stepped inner hole, and a direction in which the valve rod seats on the valve seat. A master cylinder comprising a spring that biases the valve rod.