Abstract: Provided is a shock absorber capable of improving the dimensional quality and ensuring the sealing performance of a seal ring. The shock absorber includes a cylinder, an outer tube, an intermediate tube, and a discharge passage defined between the intermediate tube and the cylinder, a reservoir defined between the intermediate tube and the outer tube. The intermediate tube includes, on its inner circumferential surface, a groove having a concave shape in cross section to be capable of accommodating a seal ring that closes the discharge passage. A relationship of ?1<?2 is satisfied, where ?1 represents an angle formed between one side surface, out of both side surfaces of the groove of the intermediate tube, that is located on an axial end side of the intermediate tube, and a plane orthogonal to an axial direction of the intermediate tube, and ?2 represents an angle formed between the other side surface that is located on an axial center side of the intermediate tube and the plane.

Abstract: Provided are a forming method and a forming apparatus which can secure strength after forming while suppressing deformation. The forming method of the present invention includes a burring step and a pressing step. In the burring step, a branch pipe is formed by causing a cylindrical peripheral wall of a cylindrical member (workpiece) having the peripheral wall to project in an outside direction in a tubular shape. In the pressing step, a distal end surface of the branch pipe is pressed toward a proximal end portion of the branch pipe. In the pressing step, the distal end surface of the branch pipe can be pressed by an end surface pressing punch in a state where a burring punch is inserted in the branch pipe.

Abstract: Provided is a shock absorber capable of improving the dimensional quality and ensuring the sealing performance of a seal ring. The shock absorber includes a cylinder, an outer tube, an intermediate tube, and a discharge passage defined between the intermediate tube and the cylinder, a reservoir defined between the intermediate tube and the outer tube. The intermediate tube includes, on its inner circumferential surface, a groove having a concave shape in cross section to be capable of accommodating a seal ring that closes the discharge passage. A relationship of ?1<?2 is satisfied, where ?1 represents an angle formed between one side surface, out of both side surfaces of the groove of the intermediate tube, that is located on an axial end side of the intermediate tube, and a plane orthogonal to an axial direction of the intermediate tube, and ?2 represents an angle formed between the other side surface that is located on an axial center side of the intermediate tube and the plane.

Abstract: Provided are a forming method and a forming apparatus which can secure strength after forming while suppressing deformation. The forming method of the present invention includes a burring step and a pressing step. In the burring step, a branch pipe is formed by causing a cylindrical peripheral wall of a cylindrical member (workpiece) having the peripheral wall to project in an outside direction in a tubular shape. In the pressing step, a distal end surface of the branch pipe is pressed toward a proximal end portion of the branch pipe. In the pressing step, the distal end surface of the branch pipe can be pressed by an end surface pressing punch in a state where a burring punch is inserted in the branch pipe.

Abstract: A rotor manufacturing method for manufacturing a rotor including a rotor core, the rotor core having a permanent magnet mounted thereon throughout a circumferential direction, includes covering an outer circumference of the rotor core with a tubular rotor cover; and forming an angular portion conforming to an outer shape of the permanent magnet by pressing an open end of the rotor cover radially inward with use of a pressing member, the open end of the rotor cover axially projecting from an end of the rotor core before being pressed.

Abstract: A knuckle bracket includes a bracket main body that has an inner peripheral shape along a tube of a shock absorber and a pair of attachment parts that are formed to protrude parallel to each other. The apparatus for manufacturing the knuckle bracket includes a width molding machine that molds a width of the pair of attachment parts in a state where the workpiece is supported on a support shaft, and a hole punching machine that machines attachment holes into the pair of attachment parts in a state where the workpiece is supported on the support shaft. The workpiece is transported from the width molding machine to the hole punching machine by moving the workpiece along the support shaft until the workpiece is above the die after the support shaft is raised and then lowering the support shaft until the support shaft abuts a top surface of the die.

Abstract: A rotor manufacturing method for manufacturing a rotor including a rotor core, the rotor core having a permanent magnet mounted thereon throughout a circumferential direction, includes covering an outer circumference of the rotor core with a tubular rotor cover; and forming an angular portion conforming to an outer shape of the permanent magnet by pressing an open end of the rotor cover radially inward with use of a pressing member, the open end of the rotor cover axially projecting from an end of the rotor core before being pressed.

Abstract: A knuckle bracket includes a bracket main body that has an inner peripheral shape along a tube of a shock absorber and a pair of attachment parts that are formed to protrude parallel to each other. The apparatus for manufacturing the knuckle bracket includes a width molding machine that molds a width of the pair of attachment parts in a state where the workpiece is supported on a support shaft, and a hole punching machine that machines attachment holes into the pair of attachment parts in a state where the workpiece is supported on the support shaft. The workpiece is transported from the width molding machine to the hole punching machine by moving the workpiece along the support shaft until the workpiece is above the die after the support shaft is raised and then lowering the support shaft until the support shaft abuts a top surface of the die.