Abstract: To achieve the foregoing object, a tubular linear motor of the present invention includes a core that has a tubular yoke and a plurality of teeth which are annular and provided at intervals in an axial direction on an outer periphery of the yoke; a winding mounted in a slot between the teeth; and a field magnet that is tubular, into which the core is movably inserted in the axial direction, and having N poles and S poles alternately arranged in the axial direction. An axial width Wi of a yoke-side inner peripheral edge of the teeth is larger than an axial width of an outer peripheral edge of the teeth.

Abstract: To achieve the above object, a cylindrical linear motor of the present invention includes a cylindrical linear motor includes: a core having a cylindrical yoke, and a plurality of teeth that are annular and are provided at intervals in an axial direction on an outer periphery of the yoke; a winding mounted in slots between the teeth; and a field which is cylindrical and in which the core is inwardly inserted movably in the axial direction to arrange N poles and S poles alternately in the axial direction, wherein the field has permanent magnets of a main magnetic pole radially magnetized and permanent magnets of a sub magnetic pole axially magnetized that are alternately arranged in a Halbach array in the axial direction, an axial length of the permanent magnet of the main magnetic pole is longer than an axial length of the permanent magnet of the sub magnetic pole, and the permanent magnet of the sub magnetic pole has a coercive force higher than that of the permanent magnet of the main magnetic pole.

Abstract: A tubular linear motor according to the present invention includes a core having a plurality of teeth having a tubular shape and provided on an outer periphery at equal intervals in an axial direction, winding wires of three phases of U-phase, V-phase, and W-phase mounted in slots between the teeth and of the core, and a field magnet having a tubular shape, in which the core is inserted inward so as to be movable in the axial direction, and a north magnetic pole and a south magnetic pole are alternately disposed on the inner periphery side in the axial direction, the field magnet has a yoke between the magnetic poles and in the axial direction, and the tubular linear motor has a two-pole 6n slot structure in which 6n slots are facing two poles, provided that n is an integer of 1 or more.

Abstract: To achieve the above object, a cylindrical linear motor of the present invention includes a cylindrical linear motor includes: a core having a cylindrical yoke, and a plurality of teeth that are annular and are provided at intervals in an axial direction on an outer periphery of the yoke; a winding mounted in slots between the teeth; and a field which is cylindrical and in which the core is inwardly inserted movably in the axial direction to arrange N poles and S poles alternately in the axial direction, wherein the field has permanent magnets of a main magnetic pole radially magnetized and permanent magnets of a sub magnetic pole axially magnetized that are alternately arranged in a Halbach array in the axial direction, an axial length of the permanent magnet of the main magnetic pole is longer than an axial length of the permanent magnet of the sub magnetic pole, and the permanent magnet of the sub magnetic pole has a coercive force higher than that of the permanent magnet of the main magnetic pole.

Abstract: A hydraulic device of the present invention includes an outer tube, a bottom portion that closes one end of the outer tube, an inner tube inserted into the outer tube, a movable portion movable relatively to the outer tube and the inner tube in an axial direction, coupling members attached to the outer periphery of the inner tube, and fixing tools that are in contact with the coupling members and fix the inner tube to the bottom portion.

Abstract: An actuator includes a cylinder made of an aluminum alloy, a bottom part that closes one end of the cylinder, a cylindrical inner rod that is inserted in the cylinder to form an annular gap to the cylinder, a cylindrical piston rod that is closed at one end, slidably contacts with an outer periphery of the inner rod, and defines, together with the inner rod, an extension-side chamber, and a piston that is provided on the piston rod, slidably contacts with an inner periphery of the cylinder, and defines a compression-side chamber between the cylinder and the piston rod, in which the bottom part has a communication hole leading to the annular gap, and the cylinder has coating formed on the inner periphery by surface treatment using an electrolytic solution.

Abstract: To achieve the foregoing object, a tubular linear motor of the present invention includes a core that has a tubular yoke and a plurality of teeth which are annular and provided at intervals in an axial direction on an outer periphery of the yoke; a winding mounted in a slot between the teeth; and a field magnet that is tubular, into which the core is movably inserted in the axial direction, and having N poles and S poles alternately arranged in the axial direction. An axial width W of a yoke-side inner peripheral edge of the teeth is larger than an axial width of an outer peripheral edge of the teeth.

Abstract: A linear actuator includes, a first tube provided with a plurality of coils placed thereinside, the plurality of coils being held by a tubular yoke; a rod movable in an axial direction inside the yoke; and a plurality of permanent magnets held by the rod while being lined up in the axial direction, the plurality of permanent magnets opposing the plurality of coils. An inner circumferential surface of the first tube has a groove running in a direction of an axis line, and wires connected to the plurality of coils are housed in the groove.

Abstract: A linear motor includes a hollow cylindrical core, a shaft having a shape of a cylindrical tube, and a sleeve. A plurality of coils are arranged at axial intervals at the inner circumferential side of the core. A plurality of permanent magnets are arranged at axial intervals in the shaft. The shaft is axially movable inside the core. The sleeve is formed from a non-magnetic element, and disposed between the core and the shaft over the entire length of the core.

Abstract: A linear actuator includes a first tube and a second tube inserted into the first tube to be free to slide. The first tube includes an outer tube and a cap provided detachably on an end portion of the outer tube, while the second tube includes a base portion and an inner tube provided detachably on the base portion and inserted into the outer tube to be free to slide. A first sliding member that slides against an outer periphery of the inner tube is provided on an inner periphery of one end of the outer tube. A second sliding member that slides against an inner periphery of the outer tube is provided on an outer periphery of an end portion of the inner tube corresponding to the other end of the outer tube.

Abstract: A linear actuator includes: a first tube provided with coils placed there inside, the coils being held by a yoke; a rod configured to be movable in the yoke in an axial direction; and permanent magnets that are held by the rod while being lined up in the axial direction so as to oppose the coils. The first tube includes an inner tube and a base portion. The inner tube has a restriction portion projecting radially inward at one end thereof. The base portion is coupled to the other end of the inner tube. The yoke is inserted into the inner tube, and fixedly held between the restriction portion and the base portion.

Abstract: A linear actuator includes, a first tube provided with a plurality of coils placed thereinside, the plurality of coils being held by a tubular yoke; a rod movable in an axial direction inside the yoke; a plurality of permanent magnets held by the rod while being lined up in the axial direction, the plurality of permanent magnets opposing the plurality of coils; and wires connected to the plurality of coils and drawn to the outside of the linear actuator via an opening provided in the first tube; and a guard member provided in the first tube so as to be interposed between the wires and the rod.

Abstract: A linear actuator includes, a first tube provided with a plurality of coils placed thereinside, the plurality of coils being held by a tubular yoke; a rod movable in an axial direction inside the yoke; a plurality of permanent magnets held by the rod while being lined up in the axial direction, the plurality of permanent magnets opposing the plurality of coils; and a pair of trunnion shafts mounted coaxially on an outer circumferential portion of the first tube. At least one of the pair of trunnion shafts is provided with a through hole. Wires connected to the plurality of coils are drawn via the through hole.

Abstract: A linear actuator includes: a first tube provided with coils placed there inside, the coils being held by a yoke; a second tube mounted on an outer circumference of the first tube; a rod fixed to an end of the second tube at one end; and permanent magnets held by the rod while being lined up in an axial direction. When the first tube and the second tube are at a fully contracted position, a gap is provided between an end face of an outer tube of the second tube and an opposing face of a base portion of the first tube.

Abstract: A linear actuator includes; a first tube provided with a plurality of coils placed thereinside, the plurality of coils being held by a tubular yoke; a rod that is movable in an axial direction inside the yoke; a plurality of permanent magnets held by the rod while being lined up in the axial direction, the plurality of permanent magnets opposing the plurality of coils; and a detent member configured to prevent relative rotations of the first tube and the yoke.

Abstract: A linear actuator includes: a first tube provided with coils placed there inside, the coils being held by a yoke; a second tube mounted on an outer circumference of the first tube; a rod fixed to an end of the second tube at one end; permanent magnets held by the rod while being lined up in an axial direction; and a joint portion disposed at the outer side of the second tube, to be joined with an external device. The rod has a non-magnetic portion at the one end fixed to the second tube. The second tube includes: an outer tube formed along the outer circumference of the first tube; and a small diameter portion that is formed along an outer circumference of the non-magnetic portion of the rod and smaller in diameter than the outer tube. The joint portion is disposed at the outer side of an end face of the small diameter portion of the second tube.

Abstract: A linear actuator that is configured to be extended/contracted by relatively displacing a first tube and a second tube in an axial direction, includes a rod that is provided inside the first tube, a plurality of permanent magnets that are held in the rod so as to be arranged in the axial direction; a stopper that is provided on a tip-end portion of the rod, a coil that is provided inside the second tube so as to face the permanent magnets, and a stopper receiving portion that is provided on the second tube so as to face the stopper, wherein the relative displacement between the first tube and the second tube in the extension direction is restricted by bringing an extension-direction-side end surface of the stopper into contact with the stopper receiving portion at a fully extended position.

Abstract: A linear actuator that is configured such that a first tube and a second tube are relatively displaced in an axial direction, includes a rod that is provided in the first tube and whose one end is fixed to an end portion of the first tube, a plurality of permanent magnets that are held by the rod so as to be arranged in the axial direction, and a tubular coil holder that is provided in the second tube and holds a coil that faces the permanent magnets, wherein the first tube has a first linear guide portion with a cylindrical surface that extends in the axial direction around the coil holder, and the second tube has a second linear guide portion with a cylindrical surface that is faced to the first linear guide portion without a gap therebetween so as to be slidably fitted therewith.

Abstract: A linear actuator for generating a thrust force for relatively displacing an outer tube and an inner tube in an axial direction includes a rod standing in an axial center part of the inner tube, a plurality of permanent magnets held side by side in an axial direction by the rod, a plurality of coils facing the permanent magnets, and a holder that is fixed to the outer tube and holds the plurality of coils. The holder includes a tubular coil holding portion that is provided in an annular space formed between the rod and the inner tube and holds the coils. A clearance is formed between the outer periphery of the coil holding portion and the inner periphery of the inner tube.

Abstract: A linear actuator is provided with an outer tube and an inner tube inserted in the outer tube so as to be free to slide axially. A rod is erected at a central axis part of the inner tube, forming an annular space between the rod and the inner tube. Permanent magnets are retained along an axial direction in the rod, and a holder is fixed to the outer tube for retaining coils which are disposed face to face with the permanent magnets. The holder includes a cylindrical coil holding portion inserted in the annular space such that an extreme end of the cylindrical coil holding portion can move further into and backward from the annular space. The coil holding portion retains the coils within an inner peripheral surface, and a flange portion joined directly to a proximal end of the coil holding portion is fixed to the outer tube.