Abstract: In an appliance having an a.c. series motor, which comprises a rotor coil configuration and two stator coils, switching means are provided for switching the a.c. series motor to different speeds or speed characteristics. Both coil ends of each of the two stator coils are accessible from outside of the a.c. series motor and are connected to the switching means. The switching means connects either one stator coil or both stator coils in series or both stator coils in parallel and in series with the rotor coil configuration.

Abstract: A motor shaft assembly method for easily and inexpensively assembling a motor shaft with components and a motor housing eliminates the need for a snap ring or a threaded nut to retain the components on the shaft.

Abstract: A surface acoustic wave device substantially eliminates a stress caused by a curing shrinkage of an adhesive and substantially eliminates a strain in a case containing a surface acoustic wave element to prevent variation in characteristics of the surface acoustic wave device. In addition, a strength of joining of bonding wires provided in the surface acoustic wave device is improved to have an improved reliability. The surface acoustic wave element of the surface acoustic wave device is fixed on a case member via a soft adhesive and bonding electrodes of the surface acoustic wave element have a plurality of through holes. Ends of the bonding wires are wire-bonded to the bonding electrodes having the through holes formed therein.

Abstract: A vibration mechanism having a magnetic spring includes a lower frame, an upper frame vertically movably mounted on the lower frame via a plurality of link mechanisms, and at least two permanent magnets mounted on the lower frame and the upper frame, respectively, with the same magnetic poles opposed to each other. A plurality of springs are connected to the link mechanisms to produce a lifting force of the upper frame. The total spring constant of the permanent magnets and the springs is partially set to a negative value or substantially zero.

Abstract: In producing a rotor for a rotating machine by bonding a rotor body and a plurality of permanent magnets to each other through a heating step and a subsequent cooling step, a rotor body having a larger coefficicient of linear thermal expansion at the cooling step has its joint surface formed by assembling of a plurality of small joint faces. Thus, it is possible to moderate a thermal stress in a brazing filler metal layer between the rotor body and each of the permanent magnets to avoid the generation of cracks in the permanent magnets having a smaller coefficient of linear thermal expansion at the cooling step and to firmly bond the rotor body and each of the permanent magnets to each other.

Abstract: The invention relates to a motor which comprises a drive system which has a stator (10) and a rotor (14), and a control system which controls the drive system and has circuit boards (21), (22), both being housed in a casing (2), wherein the casing (2) has a first conductive pin (25) for flowing a current to input power to the control system and a second conductive pin (26) for flowing a current to output from the control system to respective phases of a coil, and the circuit boards are supported by the first and second conductive pins. And, the invention relates to a method of manufacturing a motor which comprises the steps of using a first die (101) and a second die (102) which are mutually connected with a die split face (104) therebetween and a third die (103) which is inserted in the middle of the first and second dies, inserting and fixing a motor stator, a metallic cylinder and embedding members into a cavity formed by the first, second and third dies, and pouring a molten resin to effect resin molding.

Abstract: A power tool has an electric motor with a stator assembly and an armature rotatable within the stator assembly. A commutator is rotatable with the armature and is connected to the armature via a shaft. The commutator has an outer layer formed from a titanium graphite material. Brushes are associated with the commutator and are held in an end plate. The brushes are formed from a titanium graphite material.

Abstract: A drive device has an electric motor having a rotor, a rotor shaft rotatable by the rotor, a ring magnet which is rotatable during the operation of the electric motor and having at least one North pole and one South pole, a hall sensor oriented to the ring motor, the ring motor being rotatably supported at a distance from the rotor shaft near the rotor shaft, and a drive wheel arranged on the rotor shaft, the ring magnet being in a driving connection with the drive wheel, the drive wheel having a diameter which is a greater than a diameter of the ring magnet.

Abstract: A stator core for a motor in which a member with rounded edges is used to prevent the electrical breakdown of the winding of a coil which may occur at a slot edge therein. End plates 18 are disposed on ends of the stator core 10 formed of laminated magnetic steel plates 12. Each of the end plates 18 has substantially the same pattern as each magnetic steel plate 1, viewed from the axis of the motor. The elongate surface 18a of the end plate 18 continues smoothly from the inner surface 16a of each of slots 16 to the rounded edge surface 18b. The rounded edge surface extends smoothly from the elongate surface 18a to the end surface 18c of the end plate 18. This structure can eliminate sharp edges from the fringe of the slot 16, thus preventing the electrical breakdown of a coated conductor 22 in the coil which may occur at the edges.

Abstract: The invention concerns a device for securing at least one part onto the bottom of a case including at least one stud which projects from said bottom, said part having at least one substantially flat portion provided with an orifice having an axis substantially perpendicular to said bottom and into which said stud is introduced. The case further includes a cover provided, on the face thereof which is directed towards the bottom of said case, complementary means to said stud for, in a closed position of the cover, applying and holding said flat portion onto a support surface provided in the region of said bottom, and means for blocking the cover onto said case. Said complementary means are shaped for generating deformation of said distal portion outwards so that said deformed distal portion of said stud is inserted between said flat portion and said complementary means.

Abstract: A micro-actuator includes a movable member having fins that are elastically mounted thereto, and a reciprocating actuator. In rotational micro-actuators embodying the invention, the fins are attached to a peripheral surface of a rotor, and the actuator moves to compress the fins toward the peripheral surface of the rotor. This imparts a rotational force which rotates the rotor. In linear micro-actuators, fins can be attached to a movable member which is arranged to move along a track. Actuators positioned along the track can cause the fins on the movable member to compress, thereby moving the movable member along the track. In alternate linear micro-actuators, the actuators can be located on the movable member, and the fins can be located on the track. Rotational and linear micro-actuators embodying the invention could also be configured to operate in opposing directions.

Abstract: Actuators for power driven accessories for moving objects, such as vehicle power windows, windshield wipers, vehicle power antennas, power side view mirrors, catheter drivers, curtain moving machines, bi-directional rotary motors, thruster mechanisms that move relative to a reaction surface or that drive a driven member relative to itself, use orthogonal oscillatory transducers cooperatively to drive intermediary elements to move these objects bi-directionally along constrained paths. The actuators may also power a pneumatically driven autonomous robot element using dual pneumatic DSES elements such as planar contact surfaces with an array of apertures which are cyclically switched form a source of compressed air which acts as a lubricant to greatly reduce surface friction to a vacuum source, which acts as a clamping medium increasing contact frictional force. Orthogonal bladders are cyclically pressurized or vented to move a central block relative to a surrounding frame.

Abstract: The present invention resides in an improved disc-type brushless alternator which contains an alternator housing, a shaft rotatably attached to the alternator housing, a plurality of rotors and a pulley at one end. The alternator housing is attached to a stator. The rotors and stators have serrated surfaces wherein the serrated surfaces of said rotors and stators face each other and define an axial air gap there between.

Abstract: A structure of an armature of a radial rib winding type rotating electric machine which constitutes at least a member of a stator or a rotor is disclosed. The structure comprises a laminated core having an annular core portion, a radial rib-like core portion that extends radially from the annular core portion toward an opposing member and a facing core portion that is formed at the edge of the radial rib-like core portion to face the opposing member. A coil is wound about the radial rib-like core portion of the laminated core. A partial laminating core is laminated on at least the facing core portion of the armature to enlarge the facing surface thereof opposite the opposing member. The total lamination thickness of the facing core portion and partial laminating core portion is larger than the thickness of the radial rib-like core portion.

Abstract: A high energy magnetizer/demagnetizer on a nonoperative portion of a housing of a power driving tool includes a magnetizer/demagnetizer body on the nonoperative portion of the power driving tool and defining a mounting axis. At least one permanent magnet is formed of a magnetized material having North and South poles defining a magnetic axis and arranged on the body of the power driving tool to permit selective placement of a magnetizable element at at least one position along the magnetic axis at a predetermined distance from one of the poles to magnetize the element and placement of the magnetizable element at a selected distance from the other of the magnetic poles greater than the predetermined distance to demagnetize the element.

Abstract: A switched reluctance machine includes a first element having a plurality of uniform poles and a second element having a first pole and a second pole. The first pole has a wide face and the second pole has a narrow pole face. The first and second elements are disposed for movement relative to each other such that the wide and narrow poles are moveable in spaced relation to the plurality of uniform poles.

Abstract: A commutator for a dynamo-electric machine according to the present invention comprises a cylindrical commutator main body provided with a plurality of commutator segments disposed around the circumference thereof, an equalizer assembly disposed inside the commutator main body provided with equalizer segments electrically connecting commutator segments which are to have the same electric potential, and an insulating resin portion disposed within the space inside the commutator main body integrating the commutator main body and the equalizer assembly.

Abstract: A hybrid stepper motor having optimized torque per unit volume or "torque density" comprises a stator having an outer diameter and an inner diameter, and a rotor rotatably position within the stator inner diameter and being drivably coupled to a shaft. The rotor is of the permanent magnet type having at least one permanent magnet positioned on the shaft, and includes two rotor segments coupled on either end of the permanent magnet. The rotor segments each have a length which is calculated to optimize the torque density of the motor. The calculated optimization of the rotor segment length is accomplished as a function of the stator inner diameter to stator outer diameter ratio. The optimization of the rotor segment lengths allows for a range of values for a given stator inner diameter to outer diameter ratio as defined by a maximum length and a minimum length equation.

Abstract: A magnetic coupling is provided having a first shaft and a second shaft. A plurality of first magnets is in rotationally driving engagement with the first shaft and defines alternating polarity magnetic surfaces. A plurality of second magnets is in rotationally driving engagement with the second shaft and defines alternating polarity magnetic surfaces. The first and second magnet surfaces are separated by a gap so that rotation of one of the first magnets and second magnets urges synchronous rotation of the other. An electrically conductive member is in rotationally driving engagement with the second shaft and is disposed proximate to the first magnet surfaces so that rotation of the conductive member or the first magnets relative to the other induces electric current in the conductive member and urges asynchronous rotation of the other of the conductive member and the first magnets in the same rotational direction.

Abstract: An electrical machine, such as an electric motor, dynamo or alternator has a casing (26) with cooling vents (64) enabling cooling fluid (F) to flow into and out of the casing when the rotor (10) of the electrical machine rotates. The rotor (10) may be formed from conductive elements (44) connected together at their outer regions by inter-connecting members (40) which have vanes (68, 70) arranged to direct cooling fluid over the outer regions. Each conductive element (44) is a metal strip (45) with legs (46, 48) bent in opposite directions (D.sub.1, D.sub.2) relative to the plane of the strip. Portions of the windings (28, 30) of the rotor (10) are spaced apart to allow fluid to flow between the windings to enhance the cooling effect. With a current carrying rotor, the magnetic field intensity across the rotor is varied by varying the axial separation of the rotor and the stator (74, 76).