Abstract: A rotary actuator (10) is provided with a linear activation mechanism (40a) that causes a pinion (80) to rotate, and a cylinder body (12) in which a cylinder hole (28a) is formed. The linear activation mechanism (40a) comprises a rack (42) on which a plurality of teeth (44) that mesh with the pinion (80) are provided, and pistons (48a, 48b). The pistons (48a, 48b) are each provided with a piston main body (50a, 50b) that has a shape corresponding to that of the cylinder hole (28a). Each of the piston main bodies (50a, 50b) comprises a body (52a, 52b) and an extension section (54a, 54b). The ends of the rack (42) are connected to the extension sections (54a, 54b) of the set of pistons (48a, 48b), and a space (73a) shielded from the cylinder hole (28a) is formed between the bodies (52a, 52b) of the set of pistons (48a, 48b). The linear activation mechanism (40b) is also configured similarly.

Abstract: A rotary actuator (10) is provided with a linear activation mechanism (40a) that causes a pinion (80) to rotate, and a cylinder body (12) in which a cylinder hole (28a) is formed. The linear activation mechanism (40a) comprises a rack (42) on which a plurality of teeth (44) that mesh with the pinion (80) are provided, and pistons (48a, 48b). The pistons (48a, 48b) are each provided with a piston main body (50a, 50b) that has a shape corresponding to that of the cylinder hole (28a). Each of the piston main bodies (50a, 50b) comprises a body (52a, 52b) and an extension section (54a, 54b). The ends of the rack (42) are connected to the extension sections (54a, 54b) of the set of pistons (48a, 48b), and a space (73a) shielded from the cylinder hole (28a) is formed between the bodies (52a, 52b) of the set of pistons (48a, 48b). The linear activation mechanism (40b) is also configured similarly.

Abstract: A plurality of ring-shaped sealing members are spaced from each other on the outer periphery of each of first and second end caps that seal openings of first and second cylinder holes. Ring-shaped flow paths are formed between adjacent ring-shaped sealing members. Parts of air flow paths that supply and discharge compressed air to and from pressure chambers of the cylinder holes are formed by the ring-shaped flow paths.

Abstract: A plurality of ring-shaped sealing members are spaced from each other on the outer periphery of each of first and second end caps that seal openings of first and second cylinder holes. Ring-shaped flow paths are formed between adjacent ring-shaped sealing members. Parts of air flow paths that supply and discharge compressed air to and from pressure chambers of the cylinder holes are formed by the ring-shaped flow paths.

Abstract: A pusher which has a stroke shorter than that of a piston at either position on a head side or a rod side in a cylinder main body and which serves as both means for pushing the piston from a stroke end back to an intermediate stopping position and means for stopping the piston at the intermediate stopping position is disposed so as to be movable independently from the piston, and pressing means for causing the pusher to displace to the intermediate stopping position is provided.

Abstract: In air flow paths of a swinging apparatus in which racks are respectively provided to pistons of a pair for swinging in cylinder bores of a pair disposed in parallel in a casing, a pinion is engaged with the racks, and the pistons of the pair are synchronously driven in opposite directions to each other by synchronously supplying and discharging pressure air to and from opposite ends to each other of the pistons of the pair, the air flow paths for supplying and discharging the pressure air to and from opposite ends to each other of the pistons of the pair are formed between a bottom of the casing and a flow path forming member mounted to the bottom.

Abstract: A rack and a pinion respectively have stoppers constituted by a flat surface in both sides of tooth portions thereof. The stopper of the pinion is brought into contact with the stopper of the rack at both oscillating stroke ends of the rack, whereby a backlash is absorbed.

Abstract: A pusher which has a stroke shorter than that of a piston at either position on a head side or a rod side in a cylinder main body and which serves as both means for pushing the piston from a stroke end back to an intermediate stopping position and means for stopping the piston at the intermediate stopping position is disposed so as to be movable independently from the piston, and pressing means for causing the pusher to displace to the intermediate stopping position is provided.

Abstract: Of first and second two pressure chambers which are respectively formed on both sides of a first rack and a second rack, incompressible liquid is filled in the second pressure chambers which are positioned on the sides of back pressure at a driving time of the racks, and the second pressure chambers of the both racks are caused to communicate with each other via a throttle.

Abstract: A three-position stop type swing actuator has a main piston freely moving in forward and backward directions in an axial direction within a casing, an output shaft placed at a coaxial position with the main piston in such a manner as to be fixed in an axial direction and freely rotate around an axis, a conversion and transmission mechanism converting a forward and backward motion of the main piston into a rotating and swinging motion of the output shaft, and a sub piston having a stroke smaller than that of the main piston a fluid pressure operating force larger than that of the main piston and arranged within the casing in such a manner as to freely move in the forward and backward directions and be capable of being brought into contact with the main piston so as to restrict a middle stop position of the main piston.

Abstract: In air flow paths of a swinging apparatus in which racks are respectively provided to pistons of a pair for swinging in cylinder bores of a pair disposed in parallel in a casing, a pinion is engaged with the racks, and the pistons of the pair are synchronously driven in opposite directions to each other by synchronously supplying and discharging pressure air to and from opposite ends to each other of the pistons of the pair, the air flow paths for supplying and discharging the pressure air to and from opposite ends to each other of the pistons of the pair are formed between a bottom of the casing and a flow path forming member mounted to the bottom.

Abstract: A three-position stop type swing actuator has a main piston freely moving in forward and backward directions in an axial direction within a casing, an output shaft placed at a coaxial position with the main piston in such a manner as to be fixed in an axial direction and freely rotate around an axis, a conversion and transmission mechanism converting a forward and backward motion of the main piston into a rotating and swinging motion of the output shaft, and a sub piston having a stroke smaller than that of the main piston a fluid pressure operating force larger than that of the main piston and arranged within the casing in such a manner as to freely move in the forward and backward directions and be capable of being brought into contact with the main piston so as to restrict a middle stop position of the main piston.

Abstract: A rack and a pinion respectively have stoppers constituted by a flat surface in both sides of tooth portions thereof. The stopper of the pinion is brought into contact with the stopper of the rack at both oscillating stroke ends of the rack, whereby a backlash is absorbed.