45results about How to "Reduce magnetic leakage" patented technology

The invention relates to a charged particle beam lithography system comprising:

• • a charged particle optical column arranged in a vacuum chamber for projecting a charged particle beam onto a target, wherein the column comprises deflecting means for deflecting the charged particle beam in a deflection direction,
  • a target positioning device comprising a carrier for carrying the target, and a stage for carrying and moving the carrier along a first direction, wherein the first direction is different from the deflection direction, wherein the target positioning device comprises a first actuator for moving the stage in the first direction relative to the charged particle optical column,
  • wherein the carrier is displaceably arranged on the stage and wherein the target positioning device comprises retaining means for retaining the carrier with respect to the stage in a first relative position.

The invention discloses a moulding stamper for a magnetic shoe of a permanent magnet DC motor stator and a using method thereof. An upper die head consists of a bias magnetic die insert which is embedded in the center of an upper die block and is made of a non-magnetic material, and the upper die block made of a magnetic material; an lower die head consists of a hyperboloid die block made of a non-magnetic material and a lower die holder made of a magnetic material; and the radius of a curved surface of an upper head face of the lower die holder is less than that of an inner cambered surface of the magnetic shoe. The bias magnetic die insert and the hypoid die block are arranged vertically opposite to each other so as to change the trend of magnetic lines of force in a die cavity and the distribution orientation of the magnetic field in the magnetic shoe; the magnetic field intensity in the center of an outer cambered surface of the magnetic shoe is about 10 gausses; the magnetic field intensity on two sides of the magnetic shoe is gradually increased; and the magnetic field intensity in the center of the inner cambered surface of the magnetic shoe is 7-10 times that in the center of the outer cambered surface. The permanent magnet motor is provided with the obtained magnetic shoe, so that leakage of magnetism, temperature rising and noises of the motor can be reduced; air-gap magnetic flux of the motor can be increased by 10 to 15 percent; and overall performance of the permanent magnet motor can be improved.

A rotor for a brushless motor includes a shaft, a rotor core and a number of permanent magnets. The rotor core includes inner and outer annular portions. The inner annular portion has a central hole for receiving the shaft. The outer annular portion includes a number of sector segments arranged in a ring, with adjacent sector segments defining a slot there between for receiving a corresponding permanent magnet. Radially outer ends of adjacent sector segments are interconnected by a connector. The sector segments include first sector segments and second sector segments arranged alternately. The first sector segments are separated from the inner annular portion. The second sector segments are each connected to the inner annular portion by connecting arms.

The invention provides a defrosting device. The defrosting device comprises a metal cylinder body, a radio frequency generator module, a radio frequency antenna, and a detection module, wherein the metal cylinder body is provided with a defrosting chamber with a forward opening in a qualified mode, the radio frequency generator module is used for generating a radio frequency signal, the radio frequency antenna is electrically connected with the radio frequency generator module and can generate radio frequency waves with corresponding frequency in the defrosting chamber according to the radio frequency signal, and the detection module is used for detecting an incident wave signal and a reflected wave signal of the radio frequency antenna; the detection module is configured to calculate therate of change of a dielectric coefficient of a to-be-processed material according to the voltage and current of the incident wave signal and the voltage and current of the reflected wave signal to determine the defrosting progress of the to-be-processed material; the defrosting device further comprises a baffle arranged in conductive connection with the inner wall of the defrosting chamber; and the detection module is arranged in a shielding chamber enclosed by the inner wall of the baffle and the defrosting chamber, interference of the radio frequency waves generated by the radio frequency antenna to the detection module can be effectively avoided, and the accuracy of the incident wave signal and the reflected wave signal detected by the detection module is improved.

The invention discloses a permanent magnet gyromagnetic apparatus, which is used in the time-varying magnetic field field and particularly suitable for the medical treatment and rehabilitation field. The permanent magnet gyromagnetic apparatus comprises four permanent bar magnets which are respectively arranged on four corners of a quadrangle, wherein, a target area is formed in the quadrangular area. The permanent magnet gyromagnetic apparatus has the advantages of definite target area, measurable single magnetic field, small magnet volume, safe operation, selectable field density and knowable field form, and fundamentally solves the problem that the prior apparatus can not be further improved and developed and overcomes the technical difficulty with bottleneck property in the magnetic medical treatment field.

The invention relates to a three-phase launching guide rail applied to dynamic wireless power supply of an electric car and belongs to the technical field of wireless power energy transmission of theelectric car. The three-phase launching guide rail comprises multiple pi-type structures, strip-shaped ferrite magnetic cores longitudinally arranged according to a certain interval, multiple pi-typemagnetic pole structures formed by power supply cables wound around vertical rods of the pi-type magnetic cores, and a long straight type track formed by longitudinally arranging magnetic poles threeof which form one group according to the design interval. The three-phase launching guide rail has the characteristics that magnetic leakage is extremely small, and the electromagnetic compatibility is good.

The invention relates to a light and small optical fiber gyroscope structure with good environmental adaptability. A mounting base, an optical fiber ring mounting assembly, a mounting flange and an upper end cover are sequentially connected from bottom to top, and a gyroscope digital circuit board, a beam splitter and a Y waveguide are fixed on the mounting flange; in the optical fiber ring mounting assembly, an optical fiber ring base and an optical fiber ring upper cover form an annular cavity through a laser sealing welding process and are used for installing an optical fiber ring; and a gyroscope analog circuit, a temperature sensor and a light source are fixed on the mounting base. By designing the structure and used materials, miniaturization and light weight of the structural layout are realized, and the size and weight of the optical fiber gyroscope are reduced, so that the gyroscope is compact in overall structure, reasonable in layout, good in assembly manufacturability and small in size; a laser seal welding technology is adopted, so that magnetic leakage is reduced; a heat dissipation path is optimized, interference of a heat source on a heat-sensitive core component is reduced, temperature drift output by the optical fiber gyroscope is reduced, and output consistency and temperature stability of the gyroscope are improved.

The invention relates to a high-power panel EMI filter. The high-power panel EMI filter comprises a compound coil, a magnetic core, a tube shell, a cover plate, a base plate, a first interference rejection circuit and a second interference rejection circuit, wherein the compound coil is a disk-shaped structure formed by two mutually insulating leads via winding; the magnetic core is tubular and the compound coil is penetrated into the magnetic ore; one end of the tube shell is an open and hollow metal shell; the magnetic core is fixed at the bottom of the cavity of the tube shell; the cover plate is a metal plate; and the base plate is a printed circuit board. The compound coil is made into a disk shape by mutually insulating leads via winding and is placed in the tubular magnetic core, sothat a high-power compound inductor for the filter is formed, magnetic shielding and relatively high magnetic flux are realized, the power and performance of the filter are enhanced, and the problemthat the high-power inductors are high in winding difficulty is solved.

The invention discloses a receiver with a novel shielding case. The receiver comprises a bottom case, an upper cover, a sound production tube, an electromagnet drive device arranged in a cavity formed by the bottom case and the upper cover, and a vibration film component, wherein the shielding case is arranged on the bottom case and the upper cover, and the connection position of the bottom case and the upper cover is sealed by the shielding case. The receiver with the novel shielding case is simple in structure and magnetic leakage can be effectively reduced, besides the gap between the bottom case and the upper cover can be effectively sealed by the shielding case arranged on the bottom case of the receiver and the upper cover, thus magnetic leakage is prevented, magnetic interference is absent from the sound production tube of the receiver and the sound quality is ensured.

The invention discloses an axial magnetic flux leakage prevention three-rotor motor and an assembling method thereof. The three-rotor motor comprises a shell, a stepped shaft, a stator assembly and arotor assembly. The stepped shaft is rotationally installed in the shell. The stator assembly comprises an inner sleeve, a stator core and an outer sleeve. The outer sleeve is fixed on the inner wallof the shell and wraps the stator iron core. The stator core is fixed in the outer sleeve and is used for winding the winding. The inner sleeve is fixed in the stator core, and the stepped shaft penetrates through the inner sleeve. The rotor assembly comprises two lateral magnetic rings, a magnetic flux leakage prevention structure and two fixing discs. The magnetic flux leakage prevention structure comprises an inner magnetic ring and an outer magnetic ring. The inner magnetic ring is fixed on the stepped shaft and is positioned between the two lateral magnetic rings and in the inner sleeve.The outer magnetic ring is fixed on the inner walls of the fixing discs. According to the invention, the magnetic field of the double rotors can be enhanced, the magnetic flux leakage prevention structure is utilized to generate third rotating torque, magnetic leakage is reduced, mechanical energy converted from magnetic energy can be concentrated on the stepped shaft, and the utilization rate ofthe motor for electric energy can be improved.

The invention discloses a power factor corrector, which consists of iron core and coil bulk, wherein the iron core is composed of two cut symmetrical combination blocks of inner-ring typed egg-shaped bulk winded by steel band; the coil body is composed of coil bag with rough diameter coil and thin diameter coil; two symmetrical combination blocks are plugged in the coil bulk through butting pattern. The invention saves material with excellent radiation property, which reduces magnetic leakage phenomenon.

The invention discloses a hollow large torque servo motor. The servo motor comprises a hollow direct shaft, a first annular step is arranged on the portion, near the front, of the middle of the directshaft, the first annular step is sleeved with a stator core, a stator coil winds on the periphery of the stator core, the outer side of the stator core is provided with an inner rotor core, the innerside of the inner rotor core is bonded with a magnet adjusting magnetic steel through magnetic force, the two ends of the inner rotor core are fixed on a front end cover and a back end cover, and thefront end cover and the back end cover are rotationally supported on the direct shaft; the height-to-width ratio of the stator core is 0.5-3, the width of the inner rotor core is greater than that ofthe stator core, and the length of the first annular step is greater than the width of the stator core. The height-to-width ratio of the stator core is 0.5-3, not only can large enough magnetic forcebe provided, but also the large enough magnetic force transfer area can be provided, the width of the inner rotor core is greater than that of the stator core, it can be ensured that inner rotor coreacquires the large enough magnetic force, and the magnetic leakage is reduced, thereby achieving that the structure is compact, and the large torque can be transferred.

A strip line type annular isolator disclosed in the invention comprises a cavity (1), a cover plate (2), a center conductor (3), a left containing cavity (5) and a right containing cavity (6), the left containing cavity (5) and the right containing cavity (6) are arranged in the cavity (1), the left containing cavity (5) is communicated with the right containing cavity (6), two left positioning grooves (7) are formed in the inner wall of the left containing cavity (5) in the axial direction of the left containing cavity (5), and two right positioning grooves (8) are formed in the inner wall of the right containing cavity (6) in the axial direction of the right containing cavity (6). Internal threads are arranged at the upper end of the left containing cavity (5) and the upper end of the right containing cavity (6), external threads (9) are arranged on the outer wall of the cover plate (2), and the cover plate (2) is in threaded connection with the internal threads through the external threads (9). And lower rotating magnetic sheets (10) are supported in the left containing cavity (5) and the right containing cavity (6). The strip line type annular isolator has the beneficial effects of compact structure, improved assembly efficiency, suitability for mass production and good shielding effect.