Abstract: A fixture which secures a temperature detection element to a winding provided around a stator core of a motor, includes a main body to be inserted into a gap between the stator core and the winding, and an engagement portion formed on one end side of the main body on one side of the main body to engage with the rim of the opening of the winding. On the one side of the main body a recess is formed to house a temperature sensitive part of the temperature detection element. The depth of the recess is less than the maximum thickness of the temperature sensitive part of the temperature detection element.

Abstract: A fixture which secures a temperature detection element to a winding provided around a stator core of a motor, includes a main body to be inserted into a gap between the stator core and the winding, and an engagement portion formed on one end side of the main body on one side of the main body to engage with the rim of the opening of the winding. On the one side of the main body a recess is formed to house a temperature sensitive part of the temperature detection element. The depth of the recess is less than the maximum thickness of the temperature sensitive part of the temperature detection element.

Abstract: A linear motor (10) comprises a field portion (20) and an armature (15) arranged in predetermined spaced relation with the field portion and adapted to linearly move along the field portion. The field portion includes a plate (21), a plurality of permanent magnets (24) arranged adjacently to each other so as to arrange different polarities alternately on the plate, and mechanical fixing units (30) for fixing the permanent magnets mechanically on the plate. The permanent magnets are thus prevented from being separated under an external force which may be applied thereto. Each mechanical fixing unit each may include a cover portion (31) to cover the exposed surfaces of the permanent magnets. The mechanical fixing units are preferably formed of a non-or slightly-magnetic material.

Abstract: A linear driving device that reduces a cogging force with a simple structure as opposed to a drive mechanism having an existing structure, deals with a plurality of cogging waveforms having different periods, and suppresses not only the cogging force but also pitching that is vertical oscillation. The device has a structure provided with a plurality of magnet arrays in which permanent magnets having different polarities are alternately and rectilinearly arranged in the same direction, and a plurality of coil modules having a plurality of teeth and slots fitted with armature coils. The arrangement distance between the coil modules disposed along the displacing direction of each of the magnet arrays equals the sum or remainder of the length corresponding to a half of any one of periods possessed by the cogging force generated when the coil modules move by one magnetic pole and an integer multiple of the length of a magnetic pole pair.

Abstract: A field yoke (2) on which permanent magnets are mounted is fixed to a stationary member (1) of a machine. An armature (3) composed of coils is attached to a surface of a table (4), which is guided to move by a rectilinear movement guide (5), opposed to the field yoke (2). The field yoke (2) and the armature (3) constitute a linear motor. A compressed air feeding means (b) is mounted to the table (4). Compressed air jetting ports (6c) of the compressed air feeding means (6) are disposed ahead of and behind the table (4). While moving the table (4), compressed air is jetted to a movement surface, on which the table (4) moves, in order to remove foreign matter. Thus, as the movement surface on which the moving member (table (4)) of the linear motor moves is cleaned to remove the foreign matter, the movement of the table (4) is smooth. Moreover, the linear motor will not be damaged. This results in the linear motor capable of cleaning the movement surface on which the movable member of the linear motor moves.

Abstract: An electric motor, the insulating performance of the coil of which is high, contains no voids or few voids in the stator core. The coil 3 is wrapped in the sheet of insulating paper 4, which is open to the opening portion side of the slot 2 of the stator core 1, and is inserted into the slot 2. After that, molding is conducted by the insulating resin 5. When the resin 5 is entered into the slot 5, air is discharged from the slot to the opening portion. Nothing blocks this flow of air. Therefore, the generation of voids such as cavities and empty holes can be prevented, and the coil 3 can be insulated in the slot 2 under the condition that no voids are generated or the generation of voids is reduced. As no voids are generated, the dielectric strength can be enhanced. Further, the number of manufacturing processes can be decreased and the quantity of insulating paper used can be also decreased. Accordingly, it is possible to obtain an electric motor with a lower manufacturing cost.

Abstract: An electric motor with a stator structure having a high thermal conductivity from coils to a stator core, and capable of suppressing vibration of coils and adjusting an output torque and a cogging amount of the motor. A stator core is provided at its inner periphery with main teeth extending radially and spaced at regular intervals from one another. Auxiliary teeth are provided in slots formed between adjacent main teeth. Coils are arranged such that, when wound around the main teeth, their outer peripheral faces are in close contact with the auxiliary teeth. Since the coils are in contact at their central portions with the main teeth and in close contact at their outer peripheral portions with the auxiliary teeth, heat generated from the coils energized is efficiently conducted to the stator core, and removed by cooling devices provided at outer peripheral portions of the stator, thereby cooling the motor. Since the coils are fixedly held between the main and auxiliary teeth, vibration can be prevented.

Abstract: A permanent magnet (2) whose upper surface has an S pole and a permanent magnet (2) whose upper surface has an N pole are arranged on a yoke plate (10) having a predetermined width and a predetermined length in the longitudinal direction of the yoke plate, thereby constituting one field pole unit F. Tenons (61) formed on the yoke plate (10) of the field pole unit F are engaged with tenon grooves (62) formed on both side portions (7a, 7b) of a frame member (7), so that a plurality of field pole units F are held by the frame member (7) in a manner such that the field pole units F are arranged in the longitudinal direction of the frame (7), thereby constituting a permanent magnet field pole for a linear motor.

Abstract: A motor housing structure with an integrally molded electric connector comprises a front flange (26) and a molded rear housing (28) fixed respectively to the front and rear ends of the core (12) of the stator (10) of a motor, and supports a rotor (20) for rotation in rotary bearings (30, 32) held respectively on the front flange (26) and the molded rear housing (28) with a gap between the inner circumference of the stator (10) and the outer circumference of the rotor (20). The front flange (26) is formed of a metal and the rear housing (28) is formed as a lightweight resin member, by molding. An electric connector unit (40), to which an external electric connector (50) is connected to supply electric drive current to the motor, is formed integrally with the molded rear housing (28). The external electric connector (50) is plugged into the electric connector unit (40) in a direction along the axis of the motor, to electrically connect the external electric connector (50) to the electric connector unit (40).

Abstract: A method for inserting a rotor including the step of centering and guiding a first end portion of the rotor by a first guide tool having an inclined face which is in turn attached to the first end portion of the stator cooperating with a second guide tool attached to a rear end portion of the rotor shaft during initial insertion of the rotor into the stator. The rotor has a magnet which is easily chipped and is arranged on a peripheral face of the rotor. The method further includes the step of guiding a second end portion of the rotor within the stator by guiding a front end portion of a rotor shaft by a front bearing attached to the second end portion of the stator, and by guiding a rear end portion of the rotor shaft by the first guide tool attached to the first end portion of the stator cooperating with the second guide tool attached to a rear end portion of the rotor shaft.

Abstract: A chip-mounting portion of a flexible cable (18) having a light-receiving element chip mounted thereon is placed on a shielding plate (22), and a pattern portion (15b) on a fixed coding plate (15) and the shielding plate (22) are grounded, thereby shielding the periphery of the light-receiving element chip to improve noise tolerability with respect to noise generated internally.

Abstract: An injection molding machine using a linear motion type electric motor (10, 20), as a drive source, is provided, which is simple and compact in construction. The linear motion type electric motor includes a non-magnetic shaft (21) on which yokes (22) and permanent magnets (23) are alternately fitted, and an annular stator (10) having an outer tube (11) within which cores (12) and printed type coils (13-18) are alternately disposed, the shaft extending through the stator. Upon supply of three-phase alternating currect to the coils, a screw of the injection molding machine coupled to the shaft is moved in unison with the shaft to thereby perform injection operation.

Abstract: A digital servor system can swiftly stop a moving object, having a small friction resistance to the motion, at the position where the object should stop, without vibration thereof. A velocity command generating device (3) calculates a velocity command (V.sub.cmd) based on the deviation value of a position fedback from a position command detected by a position deviation detecting device (2). A velocity deviation detecting device (5) calculates a deviation (E) of a velocity fedback from the velocity command (V.sub.cmd). A torque command generating device (6) calculates a torque command (T.sub.cmd) giving a delay processing to the deviation (E), and outputs the torque command (T.sub.cmd) to a motor driving means (7).

Abstract: In an AC servomotor constructed so that the outer circumference (21b) of a stator core (21) formed by laminating thin steel plates (22) is used as part of a motor housing, bearing mounting bores (25a, 26a) for receiving bearing members (27, 28) to be mounted on a pair of brackets (25, 26) attached to the front and rear ends of the stator core (21) and mounting surfaces (25b, 25c) of the motor are formed with accurate concentricity and squareness with reference to the center bore (21a) and the outer circumference (21b) of the stator core (21) after firmly joining the brackets (25, 26) to the stator core (21). Thus, a rotor (29) is supported with high accuracy in concentricity with the stator core (21) on the brackets (25, 26) and the squareness of the output shaft (29a) to the mounting surfaces (25b, 25c) is established.

Abstract: A rotor for a synchronous motor, having a plurality of first magnetic poles formed by a plurality of permanent magnets respectively and disposed at practically equal circumferential intervals on the outer circumference of a yoke fixed to a rotatable motor shaft, and a second magnetic pole projecting radially from the yoke adjacently to each first magnetic pole and the second magnetic pole wherein the shape of the pole face of each first magnetic poles are in a circular arc and the shape of the pole face of each of second magnetic pole is determined by a given equation so that the magnetic flux distribution established by a pair of the first magnetic pole and the second magnetic pole is substantially equivalent to a sinusoidal magnetic flux distribution in the sweeping effect by the armature coils of each phase of the stator.

Abstract: In order to obtain an injection drive apparatus which is low-priced, can produce a great output torque, and has a satisfactory acceleration/deceleration characteristic, in an injection-molding machine which performs injection by driving a screw by means of servomotors, one or more ball screws (7), used to drive a screw (2) in the axial direction, are driven by means of a plurality of servomotors (M1, M2), a position detector (P1) for detecting the screw position is provided only for one servomotor (M1), and the servomotors (M1, M2) are provided individually with power amplifiers, which are controlled by means of one control circuit so that the individual servomotors (M1, M2) are controlled in synchronism with one another.

Abstract: A permanent-magnet field synchronous motor comprises a rotor body (22) having a cylindrical outer surface. A plurality of permanent magnets (25) attached to the cylindrical outer surface of the rotor body and arranged in the circumferential direction thereof form a field system. Each of the permanent magnets has an outer surface (25b) which extends circumferentially in parallel to the cylindrical outer surface of the rotor body and also has a constant thickness in the whole thereof. The inner surface and the outer surface of each of the permanent magnets has a certain configuration, respectively, each of which is composed of a plurality of straight lines and approximates to a contour line consisting of half-sine curves (S.sub.1, S.sub.2) extending between the circumferential opposite ends of each of the permanent magnets when developed in a plane surface.

Abstract: A synchronous machine comprising a stator (41) having armature windings matching to a .phi. phase power source and S number of slots (42) accommodating the armature windings, and a rotor (31) having a number of field poles (32) identical with the P number of poles of the rotor (31) and magnets (33) for exciting the field pole (32), in which where the number of the slots per pole per phase S/P.phi. is expressed by an irreducible fraction m/n, the length (W) of the portion of the field pole (32) facing to the slots (42) of the stator (41) along the circular direction is selected out of the integer multiple value of 1/n of the slot (42) pitch length (L) in the stator (41), whereby slot ripple is reduced and the lack of uniformity of the velocity at light load operation is decreased when the synchronous machine is used as a servomotor.

Abstract: A permanent magnet rotor assembly has a rotor shaft (11), and a plurality of yokes (12) extended along the axis of the rotor shaft at circumferential intervals around the rotor shaft. Permanent magnets (13) extended along the axis of the rotor shaft are held between two adjacent yokes. A pair of end plates (14, 15) attached to the axially opposite ends of the yokes are formed of a nonmagnetic material. Bosses (14a, 15a) fitting the outer circumference of the rotor shaft are formed in the respective central portions of the end plates. The bosses of the end plates are secured to the outer circumference of the rotor shaft by the compressive force of fastening rings (18, 19) mounted on the bosses by thermal shrinkage insertion.

Abstract: A motor with DC brake having a DC electromagnetic brake (10) arranged on the shaft (14) of the rotor (16) thereof, in which a partial shaft (14b) extending through and outward from the DC electromagnetic brake (10) is formed of a nonmagnetic metal material. A partial shaft (14a) extending through the rotor (16) is formed of a free cutting metal material, and partial shafts (14a) and (14b) are coaxially united to form the integral shaft (14) at a junction (18) by friction welding.