Abstract: A cylinder device includes a regulation mechanism that regulates separation distance between a front piston and a rear piston. A spring seat member of the regulation mechanism includes a spring reception part that projects toward a retainer side to receive a rear end of a spring, a cup seal holding part that projects on an opposite side from the retainer to hold a cup seal arranged on the rear piston, and a projection part that projects on the opposite side from the retainer. The projection part becomes abuttable on the retainer by a stroke of the rear piston if the spring reception part and the cup seal holding part are installed reversely-oriented on the rear piston.

Abstract: A cylinder device includes a regulation mechanism that regulates separation distance between a front piston and a rear piston. A spring seat member of the regulation mechanism includes a spring reception part that projects toward a retainer side to receive a rear end of a spring, a cup seal holding part that projects on an opposite side from the retainer to hold a cup seal arranged on the rear piston, and a projection part that projects on the opposite side from the retainer. The projection part becomes abuttable on the retainer by a stroke of the rear piston if the spring reception part and the cup seal holding part are installed reversely-oriented on the rear piston.

Abstract: A vehicle brake device includes an elastic body being formed such that a circulation of an operation fluid is permitted from a front end to a rear end of the elastic body until a filling rate of the elastic body reaches a predetermined value in a filling area where deformation of the elastic body is stopped by restraint of a control piston in a state where a forward stroke of the control piston is less than at least a predetermined stroke, but the circulation of the operation fluid is stopped when the filling rate reaches the predetermined value or more.

Abstract: A vehicle braking apparatus includes: a control piston configured to operate so that a reaction force based on the fluid pressure of the boosted fluid pressure application chamber is balanced with a braking operation input from the brake operation member; an elastic member including: a first face adapted to contact with a simulator piston connected to the brake operation member and slidably accommodated in the control piston; and a second face; a sliding member adapted to contact with the second face, the sliding member being accommodated in the control piston; a spring disposed between the sliding member and the control piston; and an odd-shaped portion disposed on at least one of the first and second faces of the elastic member, the odd-shaped portion configured to increase a contacting area of the elastic member and at least one of the simulator piston and the sliding member.

Abstract: A vehicle brake device includes an elastic body being formed such that a circulation of an operation fluid is permitted from a front end to a rear end of the elastic body until a filling rate of the elastic body reaches a predetermined value in a filling area where deformation of the elastic body is stopped by restraint of a control piston in a state where a forward stroke of the control piston is less than at least a predetermined stroke, but the circulation of the operation fluid is stopped when the filling rate reaches the predetermined value or more.

Abstract: A vehicle braking apparatus includes: a control piston configured to operate so that a reaction force based on the fluid pressure of the boosted fluid pressure application chamber is balanced with a braking operation input from the brake operation member; an elastic member including: a first face adapted to contact with a simulator piston connected to the brake operation member and slidably accommodated in the control piston; and a second face; a sliding member adapted to contact with the second face, the sliding member being accommodated in the control piston; a spring disposed between the sliding member and the control piston; and an odd-shaped portion disposed at least one of the first and second faces of the elastic member, the odd-shaped portion configured to increase a contacting area of the elastic member and at least one of the simulator piston and the sliding member.