A suspension apparatus for use in a vehicle including a body, a body-side member, a wheel, and a wheel-side member, the apparatus comprising:
- a hydraulic suspension device which is adapted to be provided between the body-side member and the wheel-side member;
- a first liquid passage;
- a first connection portion;
- a first accumulator which is connected to the first liquid passage via the first connection portion and is connected to the hydraulic suspension device via the first connection portion and the first liquid passage;
- a second liquid passage;
- a second connection portion;
- a second accumulator which is connected to the second liquid passage via the second connection portion and is connected to the first liquid passage via the second connection portion and the second liquid passage;
- and
- a liquid-flow control device which controls a flow of a hydraulic liquid between the hydraulic suspension device and at least one of the first and second accumulators,
- wherein in a state in which the liquid-flow control device allows the hydraulic liquid to flow from the hydraulic suspension device into each of the first and second accumulators, the first liquid passage and the first connection portion allow the hydraulic liquid to more easily flow therethrough into the first accumulator than the second liquid passage and the second connection portion allow the hydraulic liquid to flow therethrough into the second accumulator,
- wherein the first accumulator accommodates a first elastic body whose elastic deformation allows the hydraulic liquid to flow thereinto, and the second accumulator accommodates a second elastic body whose elastic deformation allows the hydraulic liquid to flow thereinto, and wherein the second elastic body has a spring constant higher than a spring constant of the first elastic body,
- wherein the liquid-flow control device comprises (a) a solenoid-operated valve which is provided in the first liquid passage and includes a solenoid and which is selectively switchable to at least an open state thereof and a closed state thereof, when an electric current supplied to the solenoid is controlled, and (b) a relief valve which is provided in parallel with the solenoid-operated valve and which inhibits, when a pressure difference obtained by subtracting, from a pressure of the hydraulic liquid in a first portion of the first liquid passage that is located between the relief valve and the hydraulic suspension device, a pressure of the hydraulic liquid in a second portion of the first liquid passage that is located between the relief valve and the first accumulator does not exceed a pre-set pressure, the hydraulic liquid from flowing between the hydraulic suspension device and the first accumulator and, when the pressure difference exceeds the pre-set pressure, allows the hydraulic liquid to flow from the hydraulic suspension device to the first accumulator and inhibits the hydraulic liquid from flowing from the first accumulator to the hydraulic suspension device, and
- wherein the suspension apparatus further comprises:
- an acceleration sensor which detects an acceleration of the vehicle;
- and
- a valve control device which controls, based on the acceleration detected by the acceleration sensor, the electric current supplied to the solenoid of the solenoid-operated valve, so as to selectively switch the solenoid-operated valve to the open state thereof and the closed state thereof.