Abstract: A valve member having a valve part and a piston part is accommodated in a piston accommodation cylinder part of a case reciprocatably, and a damper chamber that is substantially a sealed space is formed in an anti-valve seat side in the valve member so that fluid flows without flowing via the damper chamber. Accordingly, since the fluid does not pass through the damper chamber, a fluid force that occurs in the piston part due to a fluid flow does not change easily, thus it becomes difficult to increase hunting at the valve members. Moreover, in a vibrational component in the valve member reciprocating direction of the valve members, amplitude of the vibration can be decreased by a damping force generated in the damper chamber.

Abstract: In a check valve in which a valve part is disposed in a valve part accommodating recess movably relative to a piston part, among the valve part accommodating recess, an anti-valve seat side accommodation space formed between a surface of the valve part accommodating recess in an anti-valve seat side of the valve part and a wall surface of the valve part accommodating recess are communicated to exit side fluid passages.

Abstract: A brake apparatus capable of applying a regulator pressure regulated by a regulator valve device to an assisting chamber, to obtain a smooth brake feeling, even when a brake pedal is operated by a vehicle driver, during an automatic braking operation. A first control valve is disposed in a power pressure passage for controlling hydraulic pressure in the assisting chamber to be increased. A changeover valve device is disposed in a regulator pressure passage for selecting either one of a communicating state and a shutting-off state of the passage. A second control valve is connected to the regulator pressure passage between the changeover valve device and the assisting chamber, and controls the hydraulic pressure in the assisting chamber to be decreased.

Abstract: A stopper formed of a magnetic material and forming a portion of a magnetic circuit has a deformable portion that deforms in accordance with the pressure in a space within a sleeve. The deformable portion is provided with a pressure sensor that measures the amount of deformation of the deformable portion. The deformable portion, corresponding to a diaphragm, is formed in the stopper, which is a conventional electromagnetic valve component part. Therefore, it is no longer necessary to provide a diaphragm or a seal member.

Abstract: A brake apparatus capable of applying a regulator pressure regulated by a regulator valve device to an assisting chamber, to obtain a smooth brake feeling, even when a brake pedal is operated by a vehicle driver, during an automatic braking operation. A first control valve is disposed in a power pressure passage for controlling hydraulic pressure in the assisting chamber to be increased. A changeover valve device is disposed in a regulator pressure passage for selecting either one of a communicating state and a shutting-off state of the passage. A second control valve is connected to the regulator pressure passage between the changeover valve device and the assisting chamber, and controls the hydraulic pressure in the assisting chamber to be decreased.

Abstract: If a pressure sensor is increased in size and therefore the inside diameter of a yoke is increased, a stopper is provided with a large-diameter portion. The large-diameter portion makes it possible to reduce the air gap between the stopper and the yoke and therefore suppress an increase in magnetic resistance. Besides, a magnetic circuit member is provided at an outer peripheral side of a sleeve. The magnetic circuit member makes it possible to reduce the air gap between the yoke and an armature and therefore suppress an increase in magnetic resistance.

Abstract: If a pressure sensor is increased in size and therefore the inside diameter of a yoke is increased, a stopper is provided with a large-diameter portion. The large-diameter portion makes it possible to reduce the air gap between the stopper and the yoke and therefore suppress an increase in magnetic resistance. Besides, a magnetic circuit member is provided at an outer peripheral side of a sleeve. The magnetic circuit member makes it possible to reduce the air gap between the yoke and an armature and therefore suppress an increase in magnetic resistance.

Abstract: A stopper formed of a magnetic material and forming a portion of a magnetic circuit has a deformable portion that deforms in accordance with the pressure in a space within a sleeve. The deformable portion is provided with a pressure sensor that measures the amount of deformation of the deformable portion. The deformable portion, corresponding to a diaphragm, is formed in the stopper, which is a conventional electromagnetic valve component part. Therefore, it is no longer necessary to provide a diaphragm or a seal member.

Abstract: A cylindrical member is placed in a dead-end hole formed in a housing made of a material such as aluminum. A peripheral portion of the hole is pressed down to plastically deform the housing material and to supply the deformed material into a groove formed on an outer periphery of the cylindrical member. The cylindrical member is calked to the housing in this manner. To supply a proper amount of deformed material into the groove for obtaining a quality calking, an inflection point of a calking curve indicating a relation of a calking force and a calking stroke is detected during the calking process. After the inflection point is detected, the calking is performed by giving a predetermined calking stroke or by adding a predetermined calking force.

Abstract: A cylindrical member is placed in a dead-end hole formed in a housing made of a material such as aluminum. A peripheral portion of the hole is pressed down to plastically deform the housing material and to supply the deformed material into a groove formed on an outer periphery of the cylindrical member. The cylindrical member is calked to the housing in this manner. To supply a proper amount of deformed material into the groove for obtaining a quality calking, an inflection point of a calking curve indicating a relation of a calking force and a calking stroke is detected during the calking process. After the inflection point is detected, the calking is performed by giving a predetermined calking stroke or by adding a predetermined calking force.