98results about How to "Reduce magnetic flux" patented technology

In an electric power steering apparatus that generates an auxiliary steering torque by a brushless motor in response to a steering torque applied on a steering wheel and transmits it to an output shaft of a steering mechanism while reducing it by means of a reduction gear, the apparatus comprises a rotor ( 10 ) to which a cylindrical permanent magnet for rotational driving ( 12 ) and a member to be detected ( 13 ) for detection of a rotational angle of the rotor are attached and a cylindrical stator ( 30 ) opposed to the rotor in which a laminated core ( 16 ) on which a coil is wound, detection means ( 17 ) for detecting the rotational angle of the rotor by the member to be detected and a terminal ( 19 ) for providing connection to the coil are integrally formed by resin molding. At least one bearing ( 8, 9 ) for rotatably supporting the rotor is disposed radially inside the stator and between the permanent magnet for rotational driving and the member to be detected.

The purpose of this invention is to obtain a permanent magnet embedded type rotating electric machine in which the amount of magnetic flux of a permanent magnet can be prevented from reducing and the permanent magnet can be effectively cooled. In the permanent magnet embedded type rotating electric machine, a rotor (15) has: a rotor iron core (17) constructed by laminating and integrating magnetic steel sheets and firmly fixed to a shaft; a plurality of magnet housing openings (20) each formed so as to penetrate in an axial direction on the outer circumferential side of the rotor iron core (17) and disposed in a circumferential direction; and permanent magnets (21) housed in the respective magnet housing openings (20). An adhesive agent (22) is disposed only between the outside wall surface (20a) of the inner wall surfaces of each of the magnet housing openings (20), which is positioned outward in the radial direction, and the outside surface (21a) of the surfaces of each of the permanent magnets (21), which is positioned outward in the radial direction. The permanent magnets (21) are each disposed one-sided to the outside wall surface (20a) of each of the magnet housing openings (20) and fixed. A cooling flow path (23) through which a refrigerant flows is constituted by the inside surface (21b) of the surfaces of each of the permanent magnets (21), which is positioned inward in the radial direction, and the inside wall surface (20b) of the inner wall surfaces of each of the magnet housing openings (20), which is positioned inward in the radial direction.

A viscous clutch (30; 30') includes a stationary journal bracket (32; 32') defining a mounting shaft (32-1; 32-1'), an output member (34; 34') rotatably supported on the mounting shaft about an axis (A), an input member (34; 34') rotatably supported on the mounting shaft about the axis, and a working chamber (50; 50') defined between the input member and the output member to selectively transmit torque there between when a shear fluid is present. The mounting shaft extends axially through the viscous clutch from a front face (62; 62') of the viscous clutch to a rear face (56; 56') of the viscous clutch, with the rear face defining a mounting surface for mounting the viscous clutch at a mounting location. The front and rear faces are located at opposite sides of the viscous clutch and face in opposite directions.

The invention provides an electrical line-start motor comprising with a stator and a squirrel cage rotor adapted for rotation around a centre axis. The rotor comprises a squirrel cage winding in which a current is induced by corresponding windings of the stator, and a set of permanent magnets. To protect the magnets from excessive heat, the rotor comprises thermal barriers e.g. in the form of cavities located between the squirrel cage winding of the rotor and the magnets. Due to the thermal barriers, the thermal conductivity in a path between the windings and the magnets are reduced and the magnets are protected.

A brake is provided. The brake may include a rotor having a plurality of magnets and a plurality of ferromagnetic poles radially disposed thereabout, and a stator having a plurality of shunts and a plurality of teeth radially disposed thereabout. At least one of the plurality of shunts and the plurality of teeth may be configured to selectively move between an engagement state and a free engagement state. The teeth may be configured to generate magnetic flux with the ferromagnetic poles so as to generate a braking torque during the engagement state. The shunts may be configured to redirect the magnetic flux therethrough and reduce the braking torque between the teeth and the ferromagnetic poles during the free engagement state.

The invention discloses an external rotor motor. The external rotor motor comprises a stator formed by stacking stator punching sheets, permanent magnets and a rotor magnet yoke, wherein the permanentmagnets are the ones with non-uniform thickness; the plurality of permanent magnets are uniformly annularly arranged on the inner side surface of the rotor magnet yoke; the stator punching sheets areplaced on the inner sides of the permanent magnets; the permanent magnets with non-uniform thickness are magnetized in an unequal-diameter magnetizing manner; the permanent magnets with non-uniform thickness provides magnetic flows as well as magnetic circuits. The external rotor motor is reasonable in design; the permanent magnets with non-uniform thickness are magnetized in the unequal-diametermagnetizing manner, so that the magnetic flows are concentrated at the center of magnetic poles, the closed magnetic circuit is formed between the adjacent permanent magnets with non-uniform thickness, the magnetic flux passing through the closed rotor magnet yoke is reduced, and thus higher power can be output under a same size, the power density of the motor is improved, and the requirement onthe material of the rotor magnet yoke is also reduced.

The embodiment of the invention provides a headset and belongs to the field of electronic equipment. The headset comprises a shell and a net cover which are arranged in a split mode. A sound outlet is formed in the shell. The net cover covers the sound outlet. The net cover is made of magnetic shielding materials. A loudspeaker assembly is arranged in the shell and provided with a magnetic circuit unit. According to the headset, the net cover and the shell are arranged in the split mode, and the net cover covers the sound outlet of the shell; due to the fact that the net cover is made of the magnetic shielding materials, the outward-radiation magnetic flux of the magnetic circuit unit of the loudspeaker assembly can be reduced, the magnetic flux on the periphery of the net cover is greatly reduced, the attraction force of the magnetic circuit unit to external ferromagnetic substances is effectively weakened, the phenomenon that the ferromagnetic substances are attracted into a vibration film of the loudspeaker assembly through the net cover and the sound outlet is avoided, and it is ensured that the sound quality effect of the headset is not affected and the service life of the headset is prolonged.