Abstract: An electromagnetic pump including a piston, an electromagnetic portion that moves the piston forward, and a spring that moves the piston backward. The piston including a discharge check valve built in the piston. The piston is formed with a hollow portion that opens in an inner peripheral portion of an end surface of the piston, and a spring receiving surface formed on an outer peripheral portion of the end surface to receive the spring. The discharge check valve is fixed through plastic deformation of the piston by inserting the discharge check valve into the hollow portion from an opening of the piston, and partially pressing a portion of the spring receiving surface of the piston on an inner peripheral side after the insertion to recess the spring receiving surface and elevate an inner peripheral surface of the piston surrounding the hollow portion.

Abstract: An electromagnetic pump configured with an electromagnetic portion that generates an electromagnetic force for pressing the piston, and an urging member that urges the piston in a direction opposite to the electromagnetic force. A strainer member including a disk-shaped portion which has a disk shape and in which a strainer surface is formed, and a side portion that extends from an outer peripheral edge of the disk-shaped portion. A suction check valve being capable of sucking the working fluid via the strainer surface. The piston, the urging member, the suction check valve, and the strainer member are sequentially inserted into the cylinder from a side opposite to the electromagnetic portion, and the cover member is attached so as to press the strainer surface.

Abstract: An electromagnetic pump including a reciprocating piston in a cylinder; an electromagnetic portion that moves the piston forward; a first biasing member that moves the piston backward; a support member that supports the first biasing member and defines a pump chamber together with the cylinder and the piston; an intake valve that is incorporated into the support member, is connected to an intake port and prohibits hydraulic fluid from moving in reverse; and a discharge valve that is connected to a discharge port and prohibits the hydraulic fluid from moving in reverse. The intake valve includes a ball, an opening portion of the intake port, and a second biasing member that presses the ball against the opening portion from a side opposite to a direction in which the hydraulic fluid moves. In the opening member, an inner peripheral surface that receives the ball is formed in a taper shape.

Abstract: An electromagnetic pump configured with an electromagnetic portion that generates an electromagnetic force for pressing the piston, and an urging member that urges the piston in a direction opposite to the electromagnetic force. A strainer member including a disk-shaped portion which has a disk shape and in which a strainer surface is formed, and a side portion that extends from an outer peripheral edge of the disk-shaped portion. A suction check valve being capable of sucking the working fluid via the strainer surface. The piston, the urging member, the suction check valve, and the strainer member are sequentially inserted into the cylinder from a side opposite to the electromagnetic portion, and the cover member is attached so as to press the strainer surface.

Abstract: An electromagnetic pump including a piston, an electromagnetic portion that moves the piston forward, and a spring that moves the piston backward. The piston including a discharge check valve built in the piston. The piston is formed with a hollow portion that opens in an inner peripheral portion of an end surface of the piston, and a spring receiving surface formed on an outer peripheral portion of the end surface to receive the spring. The discharge check valve is fixed through plastic deformation of the piston by inserting the discharge check valve into the hollow portion from an opening of the piston, and partially pressing a portion of the spring receiving surface of the piston on an inner peripheral side after the insertion to recess the spring receiving surface and elevate an inner peripheral surface of the piston surrounding the hollow portion.

Abstract: An electromagnetic pump including a reciprocating piston in a cylinder; an electromagnetic portion that moves the piston forward; a first biasing member that moves the piston backward; a support member that supports the first biasing member and defines a pump chamber together with the cylinder and the piston; an intake valve that is incorporated into the support member, is connected to an intake port and prohibits hydraulic fluid from moving in reverse; and a discharge valve that is connected to a discharge port and prohibits the hydraulic fluid from moving in reverse. The intake valve includes a ball, an opening portion of the intake port, and a second biasing member that presses the ball against the opening portion from a side opposite to a direction in which the hydraulic fluid moves. In the opening member, an inner peripheral surface that receives the ball is formed in a taper shape.

Abstract: A spool is constituted by an outer spool 60 for opening and closing ports 52, 54, 56 provided in a sleeve 50 and an inner spool 70 that is contacted by a shaft 38 of a solenoid portion 30 and opens and closes a feedback chamber 58. A spring 80, which is interposed between the outer spool 60 and the inner spool 70, is designed to be capable of receiving precisely a total load of a load applied to the outer spool 60 by a feedback force generated when an output pressure reaches a predetermined pressure P1 and a load applied to the outer spool 60 by a biasing force of a spring 44. Therefore, by pushing the inner spool 70 using the solenoid portion 30 such that the outer spool 60 is moved in an axial direction via the spring 80, the respective ports 52, 54, 56 can be opened and closed, and the feedback chamber 58 can be opened from a closed state by the biasing force of the spring 80.