Abstract: A check valve of a vacuum booster device is provided with a main body assembled in a vacuum pressure inlet port, a first passage, an accommodating portion and a second passage, a valve seat formed in the first passage, a valve body accommodated in the accommodating portion, and a spring which urges the valve body toward the valve seat. The spring is configured to include an end coil portion which engages with a spring seat, an expanding and contracting coil portion which expands and contracts and is separated from a flange portion of the valve body, and a linking coil portion which is separated from the flange portion and the spring seat and links the end coil portion and the expanding and contracting coil portion.

Abstract: In this negative-pressure booster, one of a negative-pressure valve seat and a negative-pressure valve section has, provided thereto, one or more first protruding sections abutting against the other of the negative-pressure valve seat and negative-pressure valve section, at a site other than a first annular abutment site, in an initial state where an operational force has not been applied to an input member; and/or one of an atmospheric valve seat and an atmospheric valve section has, provided thereto, one or more second protruding sections abutting against the other of the atmospheric valve seat and atmospheric valve section, at a site other than a second annular abutment site, in the initial state where an operational force has not been applied to the input member.

Abstract: A vacuum booster check valve comprises: a main body attached to a vacuum inlet; a first passage, an accommodation section, and a second passage; a valve seat formed in the first passage; a valve body accommodated within the accommodation section; and springs that bias the valve body toward the valve seat. The check valve also comprises vibration absorption sections whereby, when the valve body is seated on the valve seat, one part of the valve body absorbs more vibrations imparted to the valve body compared to other parts of the valve body.

Abstract: In this negative-pressure booster, one of a negative-pressure valve seat and a negative-pressure valve section has, provided thereto, one or more first protruding sections abutting against the other of the negative-pressure valve seat and negative-pressure valve section, at a site other than a first annular abutment site, in an initial state where an operational force has not been applied to an input member; and/or one of an atmospheric valve seat and an atmospheric valve section has, provided thereto, one or more second protruding sections abutting against the other of the atmospheric valve seat and atmospheric valve section, at a site other than a second annular abutment site, in the initial state where an operational force has not been applied to the input member.

Abstract: The present invention addresses the problem of standardizing a front shell of a booster shell of a negative pressure-type booster device by modifying the shape of a reinforcement rib provided to the front shell so as to satisfy the demand for varying the installation pitch and installation angle of tie-rod holes with one and the same front shell. A front shell configuring a booster shell of a negative pressure-type booster device in combination with a rear shell includes a reinforcement rib formed by bending the shells, wherein the reinforcement rib is formed along a virtual ellipse of which the center is located at the center of the front shell, with the major axes of the ellipse disposed on a line connecting the centers of two tie-rod holes provided in the front shell.

Abstract: The present invention addresses the problem of standardizing a front shell of a booster shell of a negative pressure-type booster device by modifying the shape of a reinforcement rib provided to the front shell so as to satisfy the demand for varying the installation pitch and installation angle of tie-rod holes with one and the same front shell. A front shell configuring a booster shell of a negative pressure-type booster device in combination with a rear shell includes a reinforcement rib formed by bending the shells, wherein the reinforcement rib is formed along a virtual ellipse of which the center is located at the center of the front shell, with the major axes of the ellipse disposed on a line connecting the centers of two tie-rod holes provided in the front shell.

Abstract: A vacuum generator is provided wherein the intake vacuum of a combustion engine is led to a negative pressure device such as a vacuum booster of a brake booster device through a check valve. An idling air passage is connected to a suction pipe of the combustion engine to bypass a throttle valve arranged in the suction pipe. An ejector is arranged in the idling air passage at the downstream of an idle speed control valve in serial relation to the same, and the intake for idling is performed through the ejector. As the intake air flow passing through the idling air passage increases, the intake negative pressure which is generated at a vacuum takeout port of the ejector is further increased in absolute value, whereby the negative pressure device has a negative pressure which is further increased in absolute value.

Abstract: A vacuum generator is provided wherein the intake vacuum of a combustion engine is led to a negative pressure device such as a vacuum booster of a brake booster device through a check valve. An idling air passage is connected to a suction pipe of the combustion engine to bypass a throttle valve arranged in the suction pipe. An ejector is arranged in the idling air passage at the downstream of an idle speed control valve in serial relation to the same, and the intake for idling is performed through the ejector. As the intake air flow passing through the idling air passage increases, the intake negative pressure which is generated at a vacuum takeout port of the ejector is further increased in absolute value, whereby the negative pressure device has a negative pressure which is further increased in absolute value.