Abstract: A vehicle height control device stops the operation of vehicle height adjustment if the vehicle height at a wheel can not be increased to a target value during a height increasing operation within a predetermined time period. Automatic restoration of vehicle height adjustment occurs after a predetermined period if the vehicle height has increased to a height greater than a threshold value. However, if such a detection is not made, vehicle height adjustment is locked up.

Abstract: A rotary actuator is disclosed which changes the angular position of the rotary valve which is used to determine the attenuation presented by a shock absorber. The rotary actuator is disposed within a cylindrical piston rod of the shock absorber, and comprises a power transmission mechanism for driving the rotary valve for rotation between a first and a second position within a given range, a d.c. motor for driving the mechanism, a first stop mechanism for selectively stopping the rotation of the motor at a third position which is situated centrally within the given range, and a solenoid assembly for making the first stop mechanism operative. These components are disposed within the cylindrical piston rod in the sequence named from below to above. The power transmission mechanism includes a second stop mechanism which prevents the rotary valve from rotating outside a first and a second location which determine the given range.

Abstract: An air suspension system which includes an air spring provided between a car body and a suspension arm for adjusting the car height by changing the volume of the air spring. The air spring includes a diaphragm and an air piston formed to contact with the diaphragm. The air piston has a plurality of wall portions arranged longitudinally. Each wall portion is different in its external shape from the portion adjacent thereto. The external shapes of the air piston includes a combination of at least two shapes of the group including a straight cylindrical shape, a tapered shape converging downward and a tapered shape diverging downward.

Abstract: A method of adjusting the height of a vehicle provided with an air suspension system capable of adjusting the vehicle height and having two air chambers capable of being communicated with and shut off from each other. The method comprises the steps of shutting off temporarily one air chamber from the remaining one and supplying the compressed air to the other air chamber when the vehicle height is to be increased. The supply of the compressed air is carried out at the same time as or prior to the shutting-off.

Abstract: Comparison is made between an output from a temperature detecting element for detecting temperature of a control knob of a switch for controlling temperature, with a reference signal generated in association with a preset temperature of the control knob, and at least means for cooling or/and heating the control knob is driven on the basis of result of the comparison, whereby the control knob is held at preset temperature, so that the temperature of the control knob can be held at the preset temperature by a relatively simple control device.