Abstract: A plunger pump is provided which comprises: a pump body having a cylinder hole with an expanded diameter section; a plunger defining, together with the lid member, a pump chamber; and a coiled spring disposed within the expanded diameter section. The coiled spring includes: an effective winding section; a lid-side seat winding section; and a plunger-side seat winding section. The lid-side seat winding section has an outer diameter larger than an outer diameter of the effective winding section, and the plunger-side seat winding section has an outer diameter smaller than an outer diameter of the plunger. With this configuration, the coiled spring within the pump chamber can have increased stability, and can be located in the center of the pump chamber.

Abstract: A plunger pump is provided which comprises: a pump body having a cylinder hole with an expanded diameter section; a plunger defining, together with the lid member, a pump chamber; and a coiled spring disposed within the expanded diameter section. The coiled spring includes: an effective winding section; a lid-side seat winding section; and a plunger-side seat winding section. The lid-side seat winding section has an outer diameter larger than an outer diameter of the effective winding section, and the plunger-side seat winding section has an outer diameter smaller than an outer diameter of the plunger. With this configuration, the coiled spring within the pump chamber can have increased stability, and can be located in the center of the pump chamber.

Abstract: A disk brake for a vehicle, includes: an electric motor which has a motor shaft provided with an armature and which is attached to a caliper body so as to exhibit a power for urging a friction pad toward a disk rotor; and a Hall IC for detecting a rotational angle of the electric motor. The Hall IC is disposed within the electric motor so as to be located on an outer side of a pulser mounted on the motor shaft, and is retained by a motor case of the electric motor and a sensor cover made of a synthetic resin and detachably attached to the motor case. Thus, it is possible to reduce the number of parts by eliminating a special sealing measure.

Abstract: A disk brake for a vehicle, includes: an electric motor which has a motor shaft provided with an armature and which is attached to a caliper body so as to exhibit a power for urging a friction pad toward a disk rotor; and a Hall IC for detecting a rotational angle of the electric motor. The Hall IC is disposed within the electric motor so as to be located on an outer side of a pulser mounted on the motor shaft, and is retained by a motor case of the electric motor and a sensor cover made of a synthetic resin and detachably attached to the motor case. Thus, it is possible to reduce the number of parts by eliminating a special sealing measure.

Abstract: In a proportional booster valve V, a primary reaction piston 37 and a secondary reaction piston 38 are provided between a control piston 23 which faces at one end thereof toward a control pressure chamber 25 into which hydraulic pressure outputted from a primary master cylinder is inputted a boost pressure chambers 44 connected to secondary master cylinders, the primary reaction piston 37 being adapted to transmit at all times to the control piston 23 a reaction force corresponding to hydraulic pressure of the boost pressure chamber 44, the secondary reaction piston 38 being adapted to transmit to the control piston 23 a reaction force corresponding to the hydraulic pressure of the boost pressure chamber 44 as the hydraulic pressure of the boost pressure chamber 44 exceeds a set hydraulic pressure.

Abstract: In a proportional booster valve V, a primary reaction piston 37 and a secondary reaction piston 38 are provided between a control piston 23 which faces at one end thereof toward a control pressure chamber 25 into which hydraulic pressure outputted from a primary master cylinder is inputted a boost pressure chambers 44 connected to secondary master cylinders, the primary reaction piston 37 being adapted to transmit at all times to the control piston 23 a reaction force corresponding to hydraulic pressure of the boost pressure chamber 44, the secondary reaction piston 38 being adapted to transmit to the control piston 23 a reaction force corresponding to the hydraulic pressure of the boost pressure chamber 44 as the hydraulic pressure of the boost pressure chamber 44 exceeds a set hydraulic pressure

Abstract: An improved quick fill type master cylinder having a structure in which a piston consisting of a smaller diameter piston portion and a larger diameter piston portion is slidably fitted into a stepped cylinder bore to define a hydraulic pressure chamber as well as a hydraulic oil supply chamber therein, a relief port opening to the hydraulic pressure chamber and a supply port opening to the hydraulic oil supply chamber are placed in communication with an oil reservoir via a hydraulic oil flow passage formed longitudinally in a cylinder casing, and a valve device is incorporated in the hydraulic oil flow passage. The hydraulic oil flow passage is formed by drilling and the like from the rear end face of the cylinder casing and a valve chamber of the valve device is provided in the oil flow passage near outside opening thereof.

Abstract: A diaphragm assembly is designed to follow a drop in the level of a working fluid filled in a reservoir used with a master cylinder for the purpose of cutting off the communication between the working fluid and the outside air. The diaphragm includes a pair of opposite lower steps in the axial direction. Each of the steps comprises an upright flat portion and an upper flat portion which form parts of the bottom wall and side wall of the diaphragm, when the level of the working fluid in the reservoir reaches a predetermined lower limit. The upper flat portions of the steps are inclined to at a given angle to the horizontal, thus forming an air passage.

Abstract: A fluid-quantity alarming system for a brake cylinder comprises a brake master cylinder body, a reservoir disposed on and connected to the cylinder body to be biased relative to the central axis of the master cylinder, the reservoir including an opening in a plane passing through the central axis of the master cylinder for fluid communication between the master cylinder body and the reservoir, an attachment hole located adjacent to the corner thereof away from the central axis of the master cylinder, and at least one blind female screw adjacent to the attachment hole, a switch case including a switch therein with a lead extending from the switch, a flange attached to the lower part of the switch case with a hole therein and a screw, and a float disposed around the switch case to be vertically moved in accordance with liquid level in the reservoir. The float includes means to actuate the switch when the float is located beside the switch.

Abstract: A flanged cup-shaped transparent pane member is fitted in a window opening formed in the tank wall and held liquid-tight against the latter by means of a pane retainer plate which is inserted along the wall inside into the pane member through slit means provided therein. The retainer plate fully inserted abuts against a shoulder formation on the wall inside and serves to hold the pane member against inadvertent rotation as well as against falling off the tank wall. That portion of the retainer plate which extends across the follow interior of the cup-shaped pane member serves as a light reflector means for enabling the user to observe the liquid level in the tank with ease and accuracy. A minimum level indicator is formed on the closed end wall of the pane member and a maximum level indicator on the retainer plate at its top for convenience in replenishing the liquid tank.

Abstract: The present invention is directed to liquid-level indicating windows, especially suitable for reservoirs for master cylinder, which are characterized in that a container for housing a liquid is provided with a hole bored therein to which the liquid-level indicating window is made fit. The body of the liquid level device projects outside the container and the liquid-level indicating window has on its inside wall, at the liquid-level indicating section, a sign portion which is different from the other portions of the liquid-level indicating section in the light-path length and which is made of a material almost the same in refractive index as the liquid to be contained in the container.

Abstract: A mechanism for mounting a side mirror to a master cylinder for a motor bicycle in which a side mirror-mounting portion is formed on a handle-mounting member by which the body of a master cylinder is fixed to a handle bar. Such a mirror-mounting portion may be defined by a boss portion in integral relation to a handle-mounting member. Use may be made of the boss portion of any structure capable of retaining a side mirror-mounting shaft.