Abstract: In the expander (50) in a drum brake, when the brake is activated, the sleeve (56) is extended in the lateral directions in the drawing by the wedge (52) inserted within the housing (51), and the shoe engaged with the clip (58) is swung to press the lining (23) against the drum, and friction braking is performed. When the lining (23) wears away and the amount of movement of the sleeve (56) increases, the sleeve (56) is rotated by reciprocal action with a drive ring (62) that is engaged with the periphery of the sleeve and, thereby, the pressing screw (57) screwed thereon comes out by the amount of the increase of movement (the amount of wear on the lining). A flat surface (56c) is formed on the periphery of the sleeve and the detecting head (80) of the displacement detection apparatus detects the rotation of the sleeve (56).

Abstract: In a drum brake for a vehicle in which a pair of brake shoes 4 and 5 having an identical size are pressed against an inner face of a brake drum 1 so as to effect braking, a natural frequency of one (4) of said pair of brake shoes 4 and 5 is made different from a natural frequency of the other (5). Due to the difference in the respective natural frequencies of the right and left brake shoes 4 and 5, coupled vibrations between the brake drum 1 and the two brake shoes 4 and 5 are hard to cause, whereby it is effective in drastically reducing opportunities of generating "judder.

Abstract: A gear pump having three gears, including; a pump case consisting of a pump body and a cover for covering most of the body; three gears which are supported by a rotating shaft on the pump case and engaged with each other in series; first and second gear pumps each composed of one central drive gear and one of the driven gears on both sides of the drive gear; a non-return valve and a flow regulation valve which are opened at a predetermined pressure; an inlet port which is opened at one end of the pump case and connected through a feed path to the suction side of the two gear pumps; an outlet port formed on the discharge side of the first gear pump in the pump case; a regulation path passing from the discharge side of the second gear pump through the non-return valve to the outlet port; and a flow regulation path passing from the regulation path through the flow regulation valve to an oil pan.

Abstract: The present invention provides an eddy-current brake comprising a rotator made of a ferromagnetic material and electromagnets arranged so that the rotator will intercept the magnetic flux, wherein a braking force is produced by the eddy current generated in the rotator. An Ni-Cu-Ni three-layer thin metallic cladding 30 is provided on the inner surface of the cylindrical peripheral wall portion 11 of the rotator 10, and the coils 45 of the electromanets 40 are enclosed by a magnetic pole case 46 made of a ferromagnetic material, thereby to enable development of a large braking torque. This device is suited for use as an auxiliary brake for vehicles.

Abstract: An eddy-current brake comprising a rotor or rotors made of a ferromagnetic material and electromagnets, in which the rotor is so disposed that it crosses the magnetic flux and a braking force is produced by the eddy current generated in the rotor. The rotor is provided with a metallic layer formed from a non-magnetic material having a greater electroconductivity than the rotor, and the coil of each electromagnet is enclosed by a magnetic pole case made of a ferromagnetic material, so that the device is capable of developing a large braking torque and suited for use as an auxiliary brake for vehicles.

Abstract: An engine brake system comprising, in combination, a power absorbing oil pump driven in operative linkage with the crank shaft of the engine and a mechanism for controlling discharge pressure of said oil pump is disclosed. The pressure control mechanism comprises a main valve designed to be opened with a lift inversely proportional to the braking torque of the engine, a mechanism for adjusting the pressure on the back side of the main valve and a valve for switching the pressure on the back side of the main valve, all of which are provided in a valve box having an oil hole communicated with the discharge port of the oil pump. According to this system, in accordance as the engine speed increases, the lift of the main valve is reduced to elevate the power absorbed by the oil pump. Thus, this system is particularly useful for engine brake for vehicles.