The damper and spring unit comprises a damper, a spring member extending coaxially to the damper, a bottom spring plate and a vehicle height adjustment device for adjusting the height of the vehicle from the ground. A first damper element is connected to a wheel carrier of the suspension and a second damper element is slidable relative to the first damper element along the longitudinal axis (z). The adjustment device is interposed between the first damper element and the spring member to change the linear position of the bottom spring plate, and a bottom end of the spring member, relative to the first damper element. A hydraulic linear actuator comprising a cylinder is secured to the first damper element and a piston drivingly connected for translation with the bottom spring plate along the longitudinal axis (z) of the damper between a bottom end-of-travel position and a top end-of-travel position.

A damper with a cylinder and a rod, a spring arranged around the damper and a linear actuator arranged to change in a controlled manner the axial position of a bottom end of the spring relative to the cylinder of the damper. The actuator comprises an inner cylindrical element arranged to be mounted around the cylinder of the damper, an outer cylindrical element, which is mounted so as to be axially slidable relative to the inner cylindrical element and is arranged to support the bottom end of the spring, and a working chamber arranged to be filled with a fluid under pressure to adjust the axial position of the outer cylindrical element relative to the inner cylindrical element. The working chamber is delimited, both radially and axially, only by the inner cylindrical element and by the outer cylindrical element. The outer cylindrical element is provided with a support flange arranged to support the bottom end of the spring.

A pneumatically operable adjusting device (1) is provided for acting on a spring device (5) of a spring damper device (3) having a tubular body (2), with a tubular piece-shaped housing (4) which is designed to surround the tubular body (2) and has a passage (6) passing through a peripheral wall of the housing (4), and the adjusting device (1) has an adjusting nut (9) with an internal thread (10) which is attached to an external thread (11) of a tubular body (2), 37) of the spring damper device (3) can be brought into screw engagement, the housing (4) being designed for releasable abutment against the adjusting nut (9) and having an inner recess (7) for forming a pressure chamber (8) which is in fluid connection with the passage (6) and the inner recess (7) forming a pressure wall (24), the fluid admission of which causes a force acting on the housing (4) in the axial longitudinal direction and the housing (4) has an abutment surface (54) designed for spring force admission by the spring device.

The invention relates an elevating device of a vehicle shock absorber. It comprises a shock absorber having a cylinder body; and an elevating device disposed outside the cylinder body of the shock absorber and comprising a bushing having a leakproof flange at an end thereof and connected to an outer wall of the cylinder body, a lid having a chamber therein, an oil hole on a lateral wall thereof and disposed on the bushing and a hydraulic space defined by the chamber of the lid and the leakproof flange of the bushing, and the oil hole of the lid is connected to an oil tube.

A shock-absorbing front fork assembly of a motorcycle includes a front fork, a pressure buffering cylinder and a control valve disposed between the front fork and the pressure buffering cylinder and electrically connected with a brake system to control the communication between the front fork and the pressure buffering cylinder according to the operation of the brake system. When the brake system is not actuated, the control valve is open to make the front fork communicate with the pressure buffering cylinder, thereby making the spring supporting force relatively smaller. When the brake system is actuated, the control valve is close to make the front fork not communicate with the pressure buffering cylinder, thereby making the spring supporting force relatively larger. Therefore, the spring supporting force is adjusted by the brake operation, that raises the riding comfort and safety.

A flow path control device according to one embodiment includes a first valve, a unit main body and a control valve. The unit main body has an accommodation portion, a first radial communication hole and a side recess portion. The accommodation portion is recessed from a chamber accommodating the oil to cause the first valve to close the first radial communication hole. The side recess portion is recessed from the chamber so as to be continuous to the accommodation portion and not to be continuous to the first radial communication hole. The control valve is movable in the accommodation portion of the unit main body between a position at which a groove of the control valve communicates with the side recess portion and the first radial communication hole and a position at which the groove does not communicate with them.

A vehicle height adjustment apparatus according to one embodiment include a spring, a spring-length changing unit, a first valve, a control valve and a second valve. The spring-length changing unit changes a length of the spring in accordance with an amount of oil in a jack chamber that accommodates the oil. The first valve opens and closes a first communication path in which the oil supplied from a pump is oriented toward a reservoir chamber that stores the oil. The control valve opens and closes a discharge flow path oriented toward the reservoir chamber from a chamber that accommodates the oil to close the first valve. The second valve opens and closes a second communication path in which the oil supplied from the pump is oriented toward the jack chamber when the first valve is closed.

A vehicle height adjustment apparatus includes a control device. The control device controls the opening degree of the solenoid valve to allow a movement amount of the support member to reach a movement amount target value that corresponds to the vehicle height set in advance, in accordance with the weight applied to the vehicle. The control device controls the opening degree of the solenoid valve to change the movement amount of the support member based on a difference between a value based on the information related to the vehicle height and a vehicle height-related target value, on condition that the movement amount of the support member reaches the movement amount target value and the value based on the information related to the vehicle height obtained by the information obtaining device does not reach the vehicle height-related target value that corresponds to the vehicle height set in advance.

A vehicle height adjustment device includes a changer, a detector, and a controller. The changer is configured to change a relative position of a body of a vehicle to an axle of a wheel of the vehicle. The detector is configured to detect the relative position. The controller is configured to control the changer to change the relative position based on a detection value detected by the detector so as to control a height of the body as a vehicle height. The controller is configured to control the changer to maintain the vehicle height when there is a possibility of a malfunction in the detector.

A vehicle height adjustment device includes a changer and a controller. The changer is configured to change a relative position of a body of a vehicle relative to an axle of a wheel of the vehicle. The controller is configured to control the changer to make the relative position a target value so as to control a vehicle height of the body. The controller is configured to control the changer to maintain the relative position when there is a possibility of a malfunction in a detector configured to detect a parameter for control.