Abstract: The present invention relates to an anti-skid brake control apparatus for a brake system of wheeled vehicles. The control apparatus according to the present invention is essentially composed of a slip speed meter, a threshold value setting device and a brake oil pressure control device. The slip speed meter calculates at least one of a slip speed and a wheel acceleration. The acceleration is a time derivative of the rotational speed of a wheel. The threshold value setting device temporarily determines a threshold value for at least one of the slip speed and the wheel acceleration with reference to at least one of the slip speed and the wheel acceleration. The brake oil pressure control device controlling braking force of the brake system with reference to at least one of a comparison of the slip speed and the threshold value thereof, and a comparison of the wheel acceleration and the threshold value thereof, whereby skidding of the wheel is prevented by temporarily controlling the braking force.

Abstract: A pneumatic booster including a housing, a power piston partitioning the interior of the housing into a front chamber and a rear chamber, with the front chamber being connected permanently to a source of a first reference pressure, the rear chamber being selectively communicated with the front chamber and a source of second reference pressure which is higher than the first reference pressure through a valve mechanism, an output shaft receiving the output force from the power piston, and an input shaft receiving an input force for actuating said valve mechanism and receiving a reaction force of the output force. There are provided a device between the output shaft and the power piston for changing the reaction force with respect to the output force on the output shaft, a mechanism for rotating the output shaft around the axis thereof, and a device for preventing the rotation of the power piston relative to the housing at least at the non-actuated condition of the pneumatic booster.

Abstract: A pneumatic booster of the type including a housing, a power piston partitioning the interior of the housing into a constant pressure front chamber and a variable pressure rear chamber, a return spring disposed in the front chamber and biasing the power piston rearwards, a reaction disc mounted on the power piston, an output shaft disposed frontwards of the reaction disc, an input shaft disposed rearwards of the reaction disc, and a valve mechanism associated with the input shaft and controlling the pressure in the rear chamber. A lever is mounted on the front surface of the power piston with radially outer end thereof being biasing against the front surface of the power piston by the return spring and the radially inner end thereof being engageable with the output shaft to transmit at least a part of the output force of the booster from the power piston to the output shaft.

Abstract: A pneumatic booster including a housing, a power piston partitioning the interior of the housing into a front chamber and a rear chamber, with the front chamber being connected permanently to a source of a first reference pressure, the rear chamber being selectively communicated with the front chamber and a source of second reference pressure which is higher than the first reference pressure through a valve mechanism, an output shaft receiving the output force from the power piston, and an input shaft receiving an input force for actuating said valve mechanism and receiving a reaction force of the output force. There are provided a device between the output shaft and the power piston for changing the reaction force with respect to the output force on the output shaft, a mechanism for rotating the output shaft around the axis thereof, and a device for preventing the rotation of the power piston relative to the housing at least at the non-actuated condition of the pneumatic booster.