Abstract: A friction stir welding device includes a table that has a placement surface on which a workpiece is to be placed and is rotatable about a table rotation axis intersecting the placement surface, a tool holder movable relative to the table in a direction along the placement surface and rotatable about a holder rotation axis parallel to the table rotation axis, and a welding tool supported by the tool holder and rotating about a tool rotation axis intersecting the holder rotation axis. A control device has a biaxial operation mode in which the welding tool in a rotating state is pressed against a welding portion of a side surface of the workpiece, the welding tool is relatively moved along the welding portion by rotating the table, and the tool holder is rotated so that the welding tool is directed in a normal direction of the welding portion.

Abstract: A friction stir welding attachment includes a body configured to be attached to a spindle of a machine tool, a metalworking shaft rotatably supported by the body and including an attachment portion configured to attach a welding tool at an end thereof, and a pair of press components supported by the body and provided at respective sides across the attachment portion. The press components are each made of disc-shaped elastic material and are each supported in a manner rotatable around a rotation axis diagonally intersecting a rotation axis of the metalworking shaft.

Abstract: A friction stir welding attachment includes a body configured to be attached to a spindle supported by a spindle head of a machine tool, a metalworking shaft rotatably supported by the body wherein a welding tool is attachable to the metalworking shaft, a plurality of air motors provided in the body, and a transmission mechanism configured to transmit a rotation of each of the plurality of air motors to the metalworking shaft. A fixing portion is provided to supply external air to the plurality of air motors. A drive air distributor is provided to distribute drive air to the air motors. A rotation sensor for detecting a rotation state is provided to the metalworking shaft.

Abstract: A bidirectional shock absorber includes a cylinder housing including a liquid chamber, a shock-absorbing mechanism located inside the liquid chamber and supported by a rod sticking out of the cylinder housing. The shock-absorbing mechanism includes a pair of pistons located in the liquid chamber and attached to the rod on the respective sides of a liquid storage chamber constituting an accumulator, resistance paths formed between an outer circumferential surface of the pistons and an inner circumferential surface of a piston chamber, to apply flow resistance to the liquid, and unidirectional flow paths formed along the respective pistons and configured to block the liquid flow toward the liquid storage chamber when the corresponding piston is pressed toward the piston chamber, but to permit the liquid to flow in the opposite direction.

Abstract: A double-rod type shock absorber includes a rod, first and second pistons held by the rod, first and second piston chambers disposed on an outer side of the first and second pistons, a liquid storage chamber between the first piston and the second piston, a flow path gap formed between an outer peripheral surface of the first and second pistons and an inner peripheral surface of the liquid chamber, and first and second unidirectional flow paths which connect the first and second piston chambers with the liquid storage chamber, wherein, during reciprocating motion of the rod, the unidirectional flow path located on a front side in a movement direction of the rod is closed, and the unidirectional flow path located on a back side in the movement direction of the rod is opened.

Abstract: A double-rod type shock absorber includes a rod, first and second pistons held by the rod, first and second piston chambers disposed on an outer side of the first and second pistons, a liquid storage chamber between the first piston and the second piston, a flow path gap formed between an outer peripheral surface of the first and second pistons and an inner peripheral surface of the liquid chamber, and first and second unidirectional flow paths which connect the first and second piston chambers with the liquid storage chamber, wherein, during reciprocating motion of the rod, the unidirectional flow path located on a front side in a movement direction of the rod is closed, and the unidirectional flow path located on a back side in the movement direction of the rod is opened.

Abstract: A bidirectional shock absorber includes a cylinder housing including a liquid chamber, a shock-absorbing mechanism located inside the liquid chamber and supported by a rod sticking out of the cylinder housing. The shock-absorbing mechanism includes a pair of pistons located in the liquid chamber and attached to the rod on the respective sides of a liquid storage chamber constituting an accumulator, resistance paths formed between an outer circumferential surface of the pistons and an inner circumferential surface of a piston chamber, to apply flow resistance to the liquid, and unidirectional flow paths formed along the respective pistons and configured to block the liquid flow toward the liquid storage chamber when the corresponding piston is pressed toward the piston chamber, but to permit the liquid to flow in the opposite direction.

Abstract: Provided is a shock absorber enabling stable stop by damping at a terminal of a stroke and covering demanded impact-absorbing models. The shock absorber has a piston chamber, a start part for piston movement, a decelerating part, and an end part for stopping the piston. The start part forms a curve to provide a diameter larger than a virtual tapered surface formed within a stroke range of the piston and to be outward to a central axis of the piston chamber. In the decelerating part, a variation of diameter reduction is increased with the result that the diameter becomes smaller than the tapered surface, and a curve is formed so the change in variation of diameter reduction reaches the maximum variation point and turns negative. In the end part, the variation of diameter reduction is decreased with the result that a curve which enables piston stopping by damping is formed.

Abstract: Provided is a shock absorber enabling stable stop by damping at a terminal of a stroke and covering demanded impact-absorbing models. The shock absorber has a piston chamber, a start part for piston movement, a decelerating part, and an end part for stopping the piston. The start part forms a curve to provide a diameter larger than a virtual tapered surface formed within a stroke range of the piston and to be outward to a central axis of the piston chamber. In the decelerating part, a variation of diameter reduction is increased with the result that the diameter becomes smaller than the tapered surface, and a curve is formed so the change in variation of diameter reduction reaches the maximum variation point and turns negative. In the end part, the variation of diameter reduction is decreased with the result that a curve which enables piston stopping by damping is formed.

Abstract: A guiding signal generator and transmitter is included on a guiding device for generating and transmitting a guiding signal for guiding a tracking device. Provided on the tracking device are first and second guiding signal receivers spaced apart by a predetermined distance for receiving the guiding signal, and a controller for detecting a direction to and a distance from the guiding device based on outputs from the first and second guiding signal receivers and the predetermined distance. The configuration prevents collisions between the guiding device and the tracking device.