Matsushita Electric Industrial Co., Ltd.

Masami Wada

Fumitoshi Yamashita

Michinori Kishimoto

Toshiyuki Wakisaka

Fujio Nakagawa

Shuichi Kitayama

Yoshinari Asano

Akihiko Watanabe

Shinichiro Kawano

Hiroshi Ueda

Shoichi Koga

Mikio Hirano

Shouichi Koga

Hiroshi Dohi

Masaharu Miyagawa

Takeichi Ota

A card device to be inserted into a slot of an electronic apparatus having an electronic apparatus ground and electrically connected to this electronic apparatus, including a single antenna provided on a carrier, a card ground which is disposed on the carrier and electrically connected to the antenna, and a switch for carrying out, at a high frequency, a connection/disconnection of the card ground to/from the electronic apparatus ground in a condition where this card device is inserted in the slot.

Card device, electronic apparatus, and wireless device

Plural magnetic sheets () are laminated in circumference direction to form a cylindrical laminated core. Magnetic sheets () adjacent to each other have coupling point () at an upper section or a lower section and gap () on an opposite side of coupling point (). Coupling point () is prepared at upper section (), then lower section (), and upper section () then lower section () alternately. This structure allows assembling a radial laminated core with ease.

Linear actuator

An antenna diversity communications device switches communications paths between a plurality of antennas to improve reception in a frequency diversity communications system. Antenna selection is done in response to measurement of the receiving condition of the selected antenna. A memory unit stores frequency difference information between the current channel and the next channel. When the frequency difference between the current channel and the next channel is small enough to predict good correlation between the channels, and if current receiving conditions are good, the current channel remains connected. When the frequency difference between the current channel and the next channel is large enough to predict poor correlation, or if the receiving conditions on the current channel are bad, one of the other channels is selected.

Antenna diversity communications device

An electric bicycle 1 comprises a motor powered driving assembly 2 including a flat type DC motor a speed reduction mechanism, a control circuit, a pedal load sensor, and a pedal rotation speed sensor which are integrally assembled together, the motor powered driving assembly being disposed adjacent a lower median portion of a body frame. Through this arrangement it is possible to provide an electric bicycle which affords ease of control and good riding comfort and has relatively low center of gravity.

Electric bicycle

In the direct current motor having Ns pieces of stator teeth and Nr pieces of magnetic poles, each of the plural magnetic poles is disposed shifted with the predetermined shift angles .DELTA..theta.i around a rotor from the angular reference position defined by even angles around the axis of the rotor, respectively, and the shift angles .DELTA..theta.i are defined by the below-mentioned expression concerning the least common multiple Nc between the Ns and the Nr;

Direct current motor having a decreasing cogging torque

A method of manufacturing an inorganic bonding type rapidly solidified magnet, which is formed by energizing and sintering, after an instantaneous mutual attractive force has been applied intermittently in accordance with the electromagnetic force upon a thin piece shaped rapidly solidified magnet powder in a mold. A thin piece shaped inorganic glass having a thermal expansion ratio 9.times.10.sup.-6 /.degree. C. or less is used as the inorganic coupling agent. The magnet of the present invention having a ring shape, is effective to improve reliability as a rotor magnet in consideration of size, safety, mechanical strength, etc. of the present magnet formed in a ring shape. The electric resistance of the magnet is 10.sup.-3 through 10.sup.-1 .OMEGA.cm and is desirable as a rotor magnet of a PWM driving brushless electric motor.

Method of making isotropic bonded magnet

A method of manufacturing a permanent magnet which comprises applying one directional pressure and an electric current to an aggregate through a pair of electrodes to cause the aggregate to undergo a plastic deformation thereby to expand an axially projected surface area. The aggregate used is of a type containing alloy flakes interlocked with each other. The alloy flakes are those made of at least one rare earth metal and a ferrous component by the use of a melt quenching process.

Method of making permanent magnet containing rare earth metal and

A resin bonded magnet which comprises a resinous binder and melt quenched magnetically isotropic ferromagnetic alloy particles having a coercive force of 8 to 12 KOe of the formula: Fe.sub.100-x-y-z Co.sub.x R.sub.y B.sub.z wherein R is at least one of Nd and Pr, x is an atomic % of not less than 15 and not more than 30, y is an atomic % of not less 10 and not more than 13 and z is an atomic % of not less than 5 and not more than 8; the ferromagnetic alloy particles uniformly dispersed in the binder.

Rare earth containing resin-bonded magnet and its production

A process for producing a rare earth element-iron-boron anisotropic magnet that may generate a strong static magnetic field in vacant spaces of a magnetic circuit mounted in a motor is disclosed. The process comprises the steps of placing a billet produced of rapid solidification powder of a rare earth element-iron-boron alloy into a mold cavity, applying a primary pressure to said billet, while allowing a primary current to pass through said billet, applying to said billet a secondary pressure which is increased up to at least five times as much as the primary pressure, and applying a secondary current greater than the primary current through said billet, wherein the billet is finally subjected to plastic deformation at the temperature between the crystalline temperature and 750.degree. C.

Process for producing a rare earth element-iron anisotropic magnet

In a method for manufacturing yokes (3, FIG. 1) to be used in a permanent magnet type stepping motor (10, FIG. 2), a surface-treated dead soft steel sheet such as nickel-plated steel sheet or aluminized steel sheet containing carbon in 0.01 wt. % or less is press-worked to form yoke (3) having plural pole teeth (3a, FIG. 1) on its inner periphery, and then the yoke is annealed in an inactive gas atmosphere in a temperature range of 750.degree.-820.degree. C. to remove residual stress, and permeability of the yoke is improved.

Yoke of stepping motor and method for manufacturing the same

A process for producing a rare earth-iron-boron magnet, which includes the steps of: (1) charging a melt spun powder of a rare earth-iron-boron magnet into at least one cavity, which is confined by a pair of electrodes inserted into a hole of an electrically non-conductive ceramic die; (2) subjecting the melt spun powder to a non-equilibrium plasma treatment, under a reduced atmosphere of 10.sup.-1 to 10.sup.-3 Torr, while applying a uniaxial pressure of 200 to 500 kgf/cm.sup.2 to the melt spun powder in the direction connecting the electrodes interposed between a pair of thermally insulating members, thereby fusing the melt spun powder; and (3) heating the fused melt spun powder to a temperature higher than or equal to its crystallization temperature by transferring a Joule's heat generated in the thermally insulating members by passing a current through the members to the melt spun powder thereby causing the plastic deformation of the melt spun powder to form a rare earth-iron-boron magnet.

Process for producing a rare earth-iron-boron magnet

A process for producing resin bonded magnet structures is disclosed which includes the steps of: (a) adding a solid epoxy resin of at least one epoxy oligomer and a microcapsule which contains at least one liquid epoxy resin to a melt spun powder of a rare earth element-iron alloy to form a granulated intermediate material, wherein the epoxy oligomer has alcoholic hydroxyl groups in the molecular chain thereof and the solid epoxy resin has a softening temperature (Durran's melting point) of 65.degree. C. to 85.degree. C.; (b) mixing the granulated intermediate material with a powdered curing agent and a lubricant to form a compound; (c) forming a green body of a resin bonded magnet by compressing the compound, and then integrating the green body directly with a supporting member; and (d) curing the solid and liquid epoxy resins in the green body by application of heat to form a rigid structure of the resin bonded magnet integrated with the supporting member.

Process for producing a resin bonded magnet structure

A method for making a resin-bonded magnet of flaky pieces of a ferromagnetic alloy and a resin composition which comprises providing composite granules obtained from a mixture of magnetically isotropic pieces of an Fe-B-R alloy, in which R is Nd and/or Pr, in the form of fine pieces and a resin composition comprised of at least one film-forming polymer having a functional group reactive with isocyanate groups and a blocked isocyanate. The granules are compression molded to obtain a green compact and subsequently thermally treated to allow reaction between the at least one film-forming polymer and the isocyanate by dissociation of the blocking groups by heating, thereby obtaining a resin-bonded magnet.

Growing community of inventors

Hirakata, Japan

Masami Wada