A rotor of an embedded magnet type motor has a plurality of magnets forming magnetic poles, the number of which is represented by P. A rotor core includes first accommodation holes, the number of which is represented by P/2, extending in a radial direction, and V-shaped accommodation holes, the number of which is represented by P/2, having a V shape protruding outward in a radial direction. The first accommodation holes and the V-shaped accommodation holes are alternately arranged in a circumferential direction. The V-shaped accommodation holes include a second accommodation hole and a third accommodation hole corresponding to two straight lines forming the V shape. The first accommodation hole is adjacent to the second accommodation hole at one side in the circumferential direction, and is adjacent to the third accommodation hole at the other side. A plurality of magnets include a first magnet arranged in the first accommodation hole, a second magnet arranged in the second accommodation hole, and a third magnet arranged in the third accommodation hole. The first magnet and the second magnet form one magnetic pole. The first magnet and the third magnet form another magnet pole. Accordingly, it is possible to achieve a high torque while suppressing an increase of the number of parts of the embedded magnet type motor.

Embedded magnet type motor

A heat pipe type radiator is formed with a cooling plate mounted on an evaporative section of a heat pipe and a flat heat conductive plate mounted on a condenser section Heat-generating electronic components are brought into contact with the cooling plate and a radiation fin molded from a thin plate in a wave form is mounted on both surfaces of the heat conductive plate Other embodiments of the radiation fin include a skived fin formed by skiving a flat plate in an arch form, a pin fin and a wire fin which are composed of and so forth Since each of these fins has the large surface area for heat radiation per unit volume and is small in weight, it is suitable to use for a heat pipe type radiator for an electronic apparatus The heat generated in the electronic components transported to the heat conductive plate through the cooling plate and the heat pipe is radiated from the entire surface of the radiation fin to the ambient air The heat conductive plate is molded in a flat form and, therefore, the heat generated in the electronic components can conduct to the portion most remote from the heat pipe Further, since the radiation fin has a large surface area for heat radiation per unit volume, the heat radiation capability is improved

Heat pipe type radiation for electronic apparatus

In one embodiment, a permanent magnet rotor is provided. The permanent magnet rotor includes at least one permanent magnet and a substantially cylindrical rotor core including an outer edge and an inner edge defining a central opening. The rotor core includes a radius R, at least one pole, and at least one radial aperture extending radially though the rotor core from the outer edge to a predetermined depth less than the radius. The at least one radial aperture is configured to receive the at least one permanent magnet. The rotor further includes at least one protrusion extending into the at least one radial aperture, the at least one protrusion positioned substantially along a bottom of the at least one radial aperture and configured to facilitate retention of the at least one permanent magnet within the at least one radial aperture.

Radially embedded permanent magnet rotor and methods thereof

PROBLEM TO BE SOLVED: To provide a magnet-embedded motor capable of reducing leakage flux and maintaining stiffness. SOLUTION: The magnet-embedded motor comprises a stator and a rotor 3, and the stator is formed nearly into a cylindrical form. In the stator, a wire is wound around a plurality of teeth that are formed so that they extend toward the axis center, at an equal angle interval in the circumferential direction. The rotor 3 has a rotor core 11 and a V-shaped permanent magnet 12 and is rotatably housed inside the stator. The rotor core 11 is formed nearly into a cylindrical form, while a plurality of core sheets 20 nearly in a disk shape, in which a plurality of housing holes 61a, 61b before lamination are formed in the circumferential direction, are laminated axially. And in the rotor core 11, a plurality of housing holes 21a, 21b are formed in the circumferential direction in the housing holes 61a, 61b before lamination. The V-shaped permanent magnet 12 is housed in the housing holes 21a, 21b. Then, a bridge 62 is formed between the outer edge in the radial direction of the housing holes 61a, 61b, before lamination (outer extension section 38) in the core sheet 20 and an outer periphery, and the axial thickness of the bridge 62 is set smaller than those of other portions. COPYRIGHT: (C)2006,JPO&NCIPI

Magnet-embedded motor

It is an object of the invention to provide an eddy current speed reducer that, though simple in construction, is superior in brake efficiency. Another object is to provide an eddy current speed reducer that has a small switching stoke and is capable of rapid switching. Thus, an eddy current speed reduce according to the invention comprises a brake disk (2) connected to a rotary shaft (1); a plurality of permanent magnets (7) having a magnetic pole surface opposed to the brake disk (2); and a drive mechanism for moving the permanent magnets (7) toward and away from the brake disk (2). Preferably, it further comprises a guide sleeve (3) supported by a nonrotatable structural section not connected to the rotary shaft (1), receiving a holder ring (4) supporting the permanent magnets (7) and opposed to the brake disk (2). And in the guide sleeve (3), a ferromagnetic member (8) is positioned in opposed relationship to the brake disk (2). Alternatively, the whole including the permanent magnets (7) of the guide sleeve (3) and the opposed end surface is constructed of nonmagnetic material.

Eddy current speed reducer

PROBLEM TO BE SOLVED: To solve a problem that the rigidity and strength of a rotor is insufficient when a centrifugal force becomes larger during high-speed rotation since a part on outer circumferential side of nonmagnetic parts around a rotating shaft is only engaged with the nonmagnetic parts, in a rotating machine having a magnetic pole part 2 in which permanent magnets 5 are radially arranged around the rotating shaft in such a manner that the magnets of the same polarity face each other and clearances between the permanent magnets are filled with a laminated magnetic material (for example, a magnetic steel sheet), and also having the nonmagnetic parts in which the outer and an inner circumferential sides (including a peripheral part of the rotating shaft) are filled with a nonmagnetic material (for example, aluminum). SOLUTION: The peripheral part 6 of the rotating shaft and the magnetic material constituting magnetic pole parts of either polarity (for example, N) are constructed as a continuously integrated object. As a result, regarding the magnetic material no engagement exists on the way from the center to the outer circumference, which enhances the rigidity and the strength of the rotor during the high-speed rotation.

Rotor of rotating machine

PURPOSE: To suppress the maximum temperature of the high temperature part of a braking drum, while avoiding the drop of braking torque, so as to keep the strength to heat by providing a circumferential recess at the center in axial direction of the surface of a ferromagnetic plate or on the side of the opening end (the side of the opening end of the braking drum). CONSTITUTION: A shallow circumferential recess 21 circular in cross section is made at the center in width direction of the surface of a ferromagnetic plate 14, preferably, at the section being biased toward the side of the opening end (left end) of a braking drum from the center in width direction. The depth d of the recess 21 is approximately 1.2 to 1.4 times the space c between the inside periphery 4e of the braking drum 4 and a ferromagnetic plate 14, and the width w of the recess 21 is approximately 0.1 to 0.3 times the width of the ferromagnetic plate 14 or permanent magnet 6. By providing the recess 21 at the outer surface of the ferromagnetic plate 14, cooling effect in the vicinity of the recess 21 becomes high, and also the calorific value by eddy currents decreases a little, so temperature rise is suppressed. COPYRIGHT: (C)1992,JPO&Japio

Eddy current type reduction gear

PROBLEM TO BE SOLVED: To improve performance by preventing looseness during high-speed revolution SOLUTION: This dynamo-electric machine comprises a stator 2 and rotors 4 allocated in the stator 2 The rotor 4 further comprises a rotor iron core 42, a plurality of permanent magnets mounted to the external circumferential surface of the rotor iron core 42 in the circumferential direction, keeping an interval and protection rings 44 mounted for covering the external circumferential surface of permanent magnets 43 The protective ring 44 is configured with a low coersive force material, which has magnetic anisotropy in one axis, showing strong magnetic anisotropy in the radial direction and substantially has a constant thickness A gap 45 is formed between the external circumferential surface of the rotor iron core 42 and the internal circumferential surface of the protection ring 44 among the permanent magnets 43

Dynamo-electric machine

PROBLEM TO BE SOLVED: To increase braking force by a method, wherein the cross sections of magnets perpendicular to the central axis of a magnet supporting cylinder have trapezoidal shapes to increase the densities of fluxes applied to a brake drum by the magnets. SOLUTION: A guide cylinder 10, which is made of nonmagnetic material and has a hollow inside part with rectangular cross sections, is provided in a brake drum 7 coupled with a rotary shaft. A number of ferromagnetic plates 15 are arranged in the outer cylinder part 10a of the guide cylinder 10 in a circumferential direction at identical intervals. Magnets 14a are attached to the outer surface of a magnet supporting cylinder 14, which is rotatably supported in the hollow inside part of the guide cylinder 10 so as to have repectively two magnets face one ferromagnetic plate 15 and to have different polarities for every two sets of magnets in the circumferential direction. The circumferential dimension of the magnet 14a is gradually reduced radially outward. A distance between cross points of the side surfaces 33 or 34 of the adjacent magnets 14a which are separated from each other, and the respective outer surfaces 31 of the magnets 14a is made equal to or slightly larger than the dimension of the inner surface of the ferromagnetic late 15.

Eddy current decelerator

PROBLEM TO BE SOLVED: To provide an eddy current speed reducer which has a mechanism for automatically returning a magnet support cylinder to a non-braking position, prevents the occurrence of drag torque at the time of non-braking, and possesses a simple device configuration. SOLUTION: The eddy current speed reducer is equipped with a brake drum 7 coupled with a rotating shaft, an immovable guide cylinder disposed in the brake drum and provided with an inner cavity with a rectangular cross section, a magnet support cylinder 14 provided in the inner cavity, a plurality of magnets 24 provided on the outer peripheral surface of the magnet support cylinder at equal intervals in the peripheral direction so that polarities alternately change, and a plurality of ferromagnetism parts provided on positions corresponding to the magnets. The respective ferromagnetism parts 121 and coupled parts 122 form an integral ferromagnetic 15, and an actuator 20 is provided which is connected to the magnet support cylinder 14 so as to rotate the magnet support cylinder 14 in the peripheral direction and in the direction opposite to the usual rotation of the brake drum 7 from the non- braking position, in which two adjacent magnets with different polarities are disposed partly facing to the shared ferromagnetism part 121 to the braking positions opposed to the respective magnets. COPYRIGHT: (C)2003,JPO

徹桑原

Papers

Rotor of rotating machine

Eddy current type reduction gear

Dynamo-electric machine

Eddy current decelerator

Eddy-current speed reducer

徹 桑原

Papers

Rotor of rotating machine

Eddy current type reduction gear

Dynamo-electric machine

Eddy current decelerator

Eddy-current speed reducer

徹桑原