Abstract: Disclosed is a diaphragm having a flexible film portion and an outer peripheral flange portion integrally provided on the peripheral edge of the film portion, said outer peripheral flange portion being provided between and held by a first housing and a second housing, wherein the film portion is prevented from rising upward when the diaphragm is attached to the housings. The outer peripheral flange portion has a first pressed surface which is one surface of the diaphragm in the thickness direction and which is in close contact with the first housing, and a three-dimensional shape composed of a projected portion or a recessed portion, on the first pressed surface. When the outer peripheral flange portion is attached to the first housing and the second housing while being compressed and deformed therebetween, the three-dimensional shape defines voids in the thickness direction between the outer peripheral flange portion and the first housing.

Abstract: A pressure regulating reservoir includes, first and second conduits, a reservoir chamber, first and second reservoir ports, a valve portion including a first hydraulic passage, first and second valve bodies, and a valve seat including a second hydraulic passage, a piston portion including a piston and a spring, a mobile member, a protruding portion and a shaft, wherein the first hydraulic passage is closed by the second valve body thereby interrupting the fluid communication when the pump is not actuated, a pressure difference between a brake hydraulic pressure within the reservoir chamber and a brake hydraulic pressure within the first reservoir port is regulated when the pump is actuated while the brake hydraulic pressure is generated by the brake hydraulic pressure generating means, and the second hydraulic passage is opened to establish the fluid communication when the pump is actuated while no brake hydraulic pressure is generated.

Abstract: A pressure regulating reservoir includes, first and second conduits, a reservoir chamber, first and second reservoir ports, a valve portion including a first hydraulic passage, first and second valve bodies, and a valve seat including a second hydraulic passage, a piston portion including a piston and a spring, a mobile member, a protruding portion and a shaft, wherein the first hydraulic passage is closed by the second valve body thereby interrupting the fluid communication when the pump is not actuated, a pressure difference between a brake hydraulic pressure within the reservoir chamber and a brake hydraulic pressure within the first reservoir port is regulated when the pump is actuated while the brake hydraulic pressure is generated by the brake hydraulic pressure generating means, and the second hydraulic passage is opened to establish the fluid communication when the pump is actuated while no brake hydraulic pressure is generated.