Abstract: A control system for a continuously variable transmission has a line pressure control valve having ports and a spool for controlling the line pressure of oil supplied to a cylinder of a pulley device to change the transmission ratio. The line pressure control valve has chambers. When a motor vehicle is decelerated at coasting of the vehicle, the spool of the line pressure control valve is shifted by controlling the amount of oil supplied to the chambers of the valve, so that the line pressure increases in accordance with the magnitude of the deceleration.

Abstract: A control system for an infinitely variable transmission has a transmission ratio control valve having a spool for controlling oil supplied to a cylinder of a drive pulley to change the transmission ratio. The transmission ratio control valve has chambers at both ends of the spool. By controlling the pressure of oil supplied to the chambers in accordance with the difference between a desired transmission ratio and the actual transmission ratio, the spool is shifted, so that the speed of changing the transmission ratio is controlled.

Abstract: A control system for a continuously variable transmission for a motor vehicle has a line pressure control valve having a spool for controlling oil supplied to a cylinder of a driven pulley to change the transmission ratio. The control system operates to increase the line pressure when the vehicle stops. The increased line pressure actuate the cylinder thereby increasing the transmission ratio.

Abstract: A system is provided with an electromagnetic clutch for transmitting the output of an engine to a transmission. During deceleration of a vehicle by closing a throttle valve to an idling position, when the clutch is disengaged at a low vehicle speed, a transmission ratio control valve is operated to upshift the transmission, whereby the speed of a drive pulley of the transmission is decreased to the engine idling speed.

Abstract: An infinitely variable transmission comprises a drive pulley having a hydraulically shiftable disc, a driven pulley having a hydraulically shiftable disc, and a belt engaged with both pulleys. The system has a pressure oil circuit having a line pressure control valve having a spool for controlling line pressure, and a transmission ratio control valve having a spool for controlling the pressurized oil to change the transmission ratio. A first electromagnetic valve is provided for controlling control pressure applied to the spool of the line pressure control valve in accordance with desired transmission ratio and engine torque, and a second electromagnetic valve is provided for controlling control pressure applied to the spool of the transmission ratio control valve in accordance with the desired transmission ratio and actual transmission ratio.

Abstract: A device for measuring the position of a moving body. A detected member made of magnetic material is secured to the moving body and an E-shaped magnet is arranged adjacent the measured member transverse to the direction of motion. A Hall IC for converting the variation of magnetic flux density of the magnet to the variation of voltage is secured to an end of a central leg portion of the magnet. The measured member is an elongated bar and is provided with a series of projections on the elongated bar at both sides. The projections of both sides are arranged in staggered relation. The Hall IC is adjacent to an inner portion of one of the projections when the moving body travels in the elongated direction. The Hall IC produces an output having a waveform with a zero level interval between inverted waves.