Patent ID: 8408561

Claim:
A vehicle height adjusting device for adjusting a height of a vehicle, comprising: a spring seat that supports one end of a suspension spring of the vehicle; an operation chamber that is filled with a fluid and supports the spring seat using fluid pressure; and a screw pump that supplies a working fluid to the operation chamber, the screw pump comprising: a cylinder; a piston that slides on an inner circumference of the cylinder; a pump chamber that is defined within the cylinder by the piston and communicates with the operation chamber; a metallic nut formed integrally with or fixed to the piston, the nut having a female screw on an inner circumference thereof; a screw shaft that is driven to rotate by a motive force, the screw shaft having a male screw engaged with the female screw; and a guide member made of a non-metallic, low-friction material, which is fixed to the cylinder and fitted onto an outer circumference of the nut or the piston to guide the nut or the piston in an axial direction while preventing the nut from rotating.