Damper

A damper comprising:

• an actuator connected to a sprung member side of a vehicle, said actuator including a motion converting mechanism for transforming a linear motion into a rotational motion and a motor to which the rotational motion resulting from the transformation by the motion converting mechanism is transmitted, said motion converting mechanism including a screw shaft connected to said motor and a screw nut threadably engaged with said screw shaft rotatably;
• a hydraulic damper, said hydraulic damper including a cylinder, a piston inserted slidably into said cylinder and defining two pressure chambers within the cylinder, and a rod connected at one end thereof to said piston, wherein a linear motion of said actuator being transmitted to one of said rod and said cylinder, the other of said rod and said cylinder being connected to an unsprung member side of the vehicle, said rod being connected to said screw nut;
• biasing means being able to bias said hydraulic damper in both hydraulic damper compressing direction and hydraulic damper extending direction, said biasing means including a spring seat immovable axially with respect to one of said rod and said cylinder, said biasing means also including a pair of springs connected on one end to said spring seat, said biasing means also including a pair of spring seat portions each connected to another end of said pair of springs;
• an outer tube connected to the other of said rod and said cylinder and accommodating said hydraulic damper, said spring seat portions, said spring seat and said springs;
• an inner tube covering said screw shaft and said screw nut and inserted into said outer tube.

A damper comprising:

• an actuator connected to a sprung member side of a vehicle, said actuator including a motion converting mechanism for transforming a linear motion into a rotational motion and a motor to which the rotational motion resulting from the transformation by the motion converting mechanism is transmitted;
• a hydraulic damper, said hydraulic damper including a cylinder, a piston inserted slidably into said cylinder and defining two pressure chambers within the cylinder, and a rod connected at one end thereof to said piston, wherein a linear motion of said actuator being transmitted to one of said rod and said cylinder, the other of said rod and said cylinder being connected to an unsprung member side of the vehicle;
• and
• biasing means being able to bias said hydraulic damper in both hydraulic damper compressing direction and hydraulic damper extending direction, said biasing means including a spring seat portion immovable axially with respect to said motor, a spring seat portion immovable axially with respect to the other of said rod and said cylinder, a spring seat immovable axially with respect to one of said rod and said cylinder, and disposed between said spring seat portions, and a pair of springs interposed in two positions respectively between said spring seat portions and said spring seat.

A damper comprising:

• an actuator connected to a sprung member side of a vehicle, said actuator including a motion converting mechanism for transforming a linear motion into a rotational motion and a motor to which the rotational motion resulting from the transformation by the motion converting mechanism is transmitted;
• a hydraulic damper, said hydraulic damper including a cylinder, a piston inserted slidably into said cylinder and defining two pressure chambers within the cylinder, and a rod connected at one end thereof to said piston, wherein a linear motion of said actuator being transmitted to one of said rod and said cylinder, the other of said rod and said cylinder being connected to an unsprung member side of the vehicle;
• and
• biasing means being able to bias said hydraulic damper in both hydraulic damper compressing direction and hydraulic damper extending direction, said biasing means including a spring seat immovable axially with respect to one of said rod and said cylinder, said biasing means also including a pair of springs connected on one end to said spring seat, said biasing means also including a pair of spring seat portions each connected to another end of said pair of springs;
• permitting means for permitting circumferential rotation of said springs, said permitting means including annular members interposed in two positions respectively between said spring seat portions and said springs, in two positions respectively between one of said springs and said spring seat and between the other of said springs and associated said spring seat portion, or in two positions respectively between one of said springs and associated said spring seat portion and between the other of said springs and said spring seat.