201results about How to "Uniform magnetic field distribution" patented technology

The invention relates to a small CPT atomic clock physical system, and belongs to the technical field of atomic frequency standard. The physical system comprises a laser portion and an atom air chamber portion. The laser portion comprises a VCSEL laser tube, an aperture diaphragm, and a [lambda] / 4 wave plate. The atom air chamber portion comprises an atom air chamber, a C field coil, a thermistor, a low electromagnetic film electric heating sheet, and a photoelectric detector. The C field coil uses a reverse Helmholtz coil structure to realize. Heating methods of the low electromagnetic film electric heating sheet and high-frequency AC electric heating are used to heat the atom air chamber. The system uses a vacuum heat insulation technology to package. The output frequency of the physical system is high in stability, stable in performance, small in volume, low in power consumption, and low in cost, and is especially suitable to be used for a glass type atom air chamber whose sealing port is on the central position of a cylindrical surface.

The invention discloses an omnidirectional A0 modal Lamb wave electromagnetic acoustic sensor, and belongs to the field of ultrasonic non-destructive testing. A double-layer spiral inflection coil structure is integrated in a flexible circuit board, and the omnidirectional A0 modal Lamb wave electromagnetic acoustic sensor is designed and developed to excite single A0 modal Lamb waves in an aluminum plate. The developed electromagnetic acoustic sensor is verified by experiments, the single A0 modal Lamb waves can be excited in the aluminum plate, defects in the aluminum plate are detected by the sensor, and positioning precision is high. The developed electromagnetic acoustic sensor has fine frequency response characteristics according to verification by scanning frequency experiments, and the developed electromagnetic acoustic sensor has fine omnidirectional characteristics according to verification by omnidirectional characteristic testing experiments. By the aid of the developed omnidirectional A0 modal Lamb wave electromagnetic acoustic sensor and an array combination imaging algorithm thereof, wide-range and high-efficiency defect imaging of a plate structure can be realized, and the sensor has great application values and potentials in the field of health monitoring and non-destructive evaluation for the plate structure.

The continual casting directional solidification method for TiAl-base alloy plate comprises, putting TiAl alloy material bar 3 and dummy ingot 4 with rectangular intersection into the electromagnetic induction range of coil 6, galvanizing to coil 6 with single-phase alternating current with power of 75~100kW from electrical power for 20~25min; the alloy bar 3 and ingot 4 move downward with velocity of 0.01-0.05mm / min and get into the bottom crystallizer 8. This invention overcomes the limit to rectangular intersection blank and fits to press for high performance material in economy, science and national defense industry.

A magnetic circuit for coaxial speaker includes a first magnetic unit, at least one second magnetic unit arranged around the first magnetic unit and at least one third magnetic unit arranged around the at least one second magnetic unit. The magnetic pole arrangement of the second magnetic unit is reversed to the magnetic pole arrangement of the first magnetic unit and the second magnetic unit, enabling a first magnetic loop to be established between the first magnetic unit and the at least one second magnetic unit and a second magnetic loop to be established between the at least one second magnetic unit and the at least one third magnetic unit. The magnetic circuit is practical for use in the inner and outer drivers of a coaxial speaker, providing uniform magnetic field distribution, and facilitating speaker miniaturization.

The invention provides a Cr-Cr nanometer composite metal ceramic coating as well as a preparation method and device thereof. The coating is provided with a Cr diffusion layer, a Cr bonding layer, a Cr transition layer, a CrNx supporting layer, a Cr / CrN corrosion-resistant layer and a Cr decoration layer, wherein the CrNx supporting layer satisfies 0<=x<1; the Cr / CrN corrosion-resistant layer is an alternating layer of Cr layers and CrN layers and provided with at least one layer of Cr layer and one CrN layer. The coating provided by the invention has gradual changes of structure and composition, good interlayer bonding and excellent corrosion resistance and comprehensive properties.

The invention belongs to the technical field of sensors, aims at solving the problem that existing differential transformer type displacement sensors are poor in linearity and low in accuracy and provides a differential transformer type displacement sensor which comprises a primary coil, secondary coils and a framework. The framework is of a cylindrical structure, the primary coil and the secondary coils are wound on the framework, and magnetic conductors are arranged on the framework and are symmetric according to central axis of the framework. When an iron core of the differential transformer type displacement sensor moves in a direction being close to the secondary coils, the magnetic conductors enable magnetic flux passing the secondary coils to be increased greatly, so that magnetic field distribution in the differential transformer type displacement sensor is improved and enabled to be more uniform; a sum of magnetic flux increment of the secondary coils is ensured to be similar to linear changing, so that linearity and output accuracy of the differential transformer type displacement sensor are improved while linear stroke of the same is increased.

The invention discloses a transmitting coil structure with high-quality factor and a winding method thereof. A transmitting coil comprises a coil, an insulation layer attached to the coil and a shielding layer attached to the insulation layer. The coil is composed of M turns of loosely-intertwined winding wires and N turns of closely-intertwined winding wires. The spacing distance between turns of M turns of loosely-intertwined winding wires is larger than that between turns of N turns of closely-intertwined winding wires. M is less than N.The coil winding method thereof can help greatly the proximity effect of the coil, reduce loss and decrease the dead zone range of a magnetic field of the transmitting coil such that the quality factor of the transmitting coil is greatly increased. In addition, uniform magnetic field distribution is generated around the transmitting coil so that energy is effectively transmitted.

The present invention provides a double-layer sector array folded coil structure integrated in a flexible circuit board, and designs and develops an arrayed omnidirectional type horizontal shear modal magnetostrictive transducer. Based on the magnetostrictive effect of ferromagnetic material nickel, the transducer realizes excitation of omnidirectional horizontal shear modal SH wave in the plate structure. Test verifies that the developed arrayed omnidirectional type horizontal shear modal magnetostrictive transducer can excite single SH0 modal waveguide inaluminum plate, and verifies that the developed omnidirectional type horizontal shear modal magnetostrictive transducer has better frequency response characteristics. The developed omnidirectional type horizontal shear modal magnetostrictive transducer and an array combined imaging algorithm can achieve efficient defect imaging on plate structure in wide range and board structure, and has very great value and potential in health monitoring and non-destructive evaluation of the plate structure.

The invention provides an intermediate-voltage concatenated frequency converter, a pre-charging method and an intermediate-voltage concatenated frequency converter system. The intermediate-voltage concatenated frequency converter comprises a phase shift transformer, a power unit group and a pre-charging module, wherein the pre-charging module is used for converting power voltage input by the input end of the pre-charging module into pre-charging voltage which is consistent with the output voltage of a secondary winding of the phase shift transformer; the pre-charging voltage is connected with and output to any secondary winding of the phase shift transformer or the input end of any power unit of the power unit group through the output end of the pre-charging module to pre-charge the intermediate-voltage concatenated frequency converter; the pre-charging module comprises a contactor, a resistor and a transformer, and is connected to the low-voltage side of the intermediate-voltage concatenated frequency converter; and all the devices of the pre-charging module adopt low-voltage devices. By the technical scheme, the downsizing of a circuit is facilitated.

The invention discloses a set of motor equipment, and aims to provide a permanent magnet motor capable of effectively eliminating a slot effect. The permanent magnet motor adopts the structure that a rotor of the permanent magnet motor is a surface-mount permanent magnet, a stator of the permanent magnet motor adopts a split structure, boot tips are arranged at tooth boots of stator splits, the boot tips of two adjacent stator splits in the circumferential direction are closely contacted with each other and barely have clearance therebetween, notches are formed at the contact parts of the boot tips of the stator tooth boots of the permanent magnet motor, the permanent magnet takes the shape of an eccentric equant tile, the permanent magnet is segmented in the axial direction, the segments of the permanent magnet are placed at intervals, the homopolar permanent magnet segments are sequentially arranged in a malposed manner in the same circumferential direction, and the total malposition distance is the width of a slot. In the permanent-magnet motor provided by the invention, a specific structural combination is adopted to effectively eliminate the slot effect of the permanent magnet motor. The permanent magnet motor provided by the invention has simple manufacturing technology and lower manufacturing cost.

The invention relates to the technical field of marine power, in particular to a magnetorheological elastomer thrust bearing base dynamic vibration absorber and a use method. The dynamic vibration absorber is arranged on a thrust bearing base and comprises magnet yoke sets, a magnetism isolating support shaft, a magnetic conductive shaft sleeve, magnetorheological elastomers and an electromagnetic assembly. The outer layer of the magnetism isolating support shaft is sleeved with the magnetic conductive shaft sleeve. The two ends of the magnetic conductive shaft sleeve are provided with the parallelly arranged magnet yoke sets correspondingly. The joints of the magnetic conductive shaft sleeve and the magnet yoke sets are provided with the magnetorheological elastomers. At least one electromagnetic assembly is arranged around the part, between the two magnet yoke sets, of the magnetic conductive shaft sleeve. According to the magnetorheological elastomer thrust bearing base dynamic vibration absorber and the use method, longitudinal vibration of the thrust bearing base is controlled effectively, then the transmitting ratio of pulsating force of a propeller through the bearing base to a boat body is lowered, and the purpose of reducing of radiation noise is achieved.

The invention discloses a method for compound magnetic powder flaw detection, comprising the following steps: (1) pretreating; (2) magnetizing; (3) applying magnetic powder or magnetic suspension; (4) observing and recording a magnetic trace; (5) rating the flaw; (6) demagnetizing; and (7) post-treating. The magnetizing mode in the step (2) is circumferential closed magnet yoke magnetization and coil magnetization full sensing. The magnetic powder flaw detection method designed by the technical scheme of the invention has the advantage of high work efficiency, lightens the labor intensity of workers, avoids fire striking phenomenon, does not burn workpieces and has even magnetic field distribution.

The invention discloses a refrigerator. The refrigerator comprises a box body, a sterilizing box for containing food, a magnetic field generator and a sterilizing chamber door body; a refrigeration chamber, a sterilizing chamber and a compressor bin provided with a compressor are defined in the box body; the sterilizing box is arranged in the sterilizing chamber and is provided with an opening. The magnetic field generator is arranged on the sterilizing box to form a magnetic field in the sterilizing chamber. The sterilizing chamber door body is arranged on the box body or the sterilizing box to open or close the opening. According to the refrigerator, food storage is not influenced, and the magnetic field generator is placed in the sterilizing chamber to generate the magnetic field for sterilization, so the magnetic field intensity is convenient to improve, the magnetic field distribution is uniform, the omnibearing sterilization without a dead corner is realized, and the sterilization efficiency of the magnetic field for food is improved. In addition, harmful chemical substances are not used in the refrigerator, and the food safety is ensured. The refrigerator has the dual functions of sterilization and refrigeration, so the deadline of the fresh keeping quality of food is greatly prolonged, and the practicability of the refrigerator is improved.

The rectangle cold crucible system fit to casting continually and directional solidification comprises mould cavity 1-1 of crucible body 1 with proportion of width, length and height as 1:2~6:10~20 that belongs to fillet transition of two near surfaces and four square platform of big end down; opening splits with number about 6~18 run through outer surface 1-2 to mould cavity 1-1 on crucible body 1. This invention has no pollution to material, prepares heterotype alloy blank of high quality, overcomes the limit to rectangular intersection blank and fits to requirement of metallurgical and aerospace industry.

The invention discloses an electric machine having in each case at least two clamping protrusions for attaching a permanent magnet. The present invention relates to a spoke rotor for an electric machine, having a main body which extends concentrically around an axis of rotation and which has a plurality of pole shoes, between which permanent magnets are arranged in holders, wherein there is provided for each permanent magnet in its holder in each case at least one first clamping element and one second clamping element, which fixes said permanent magnet in the holder, wherein the first clamping element fixes the permanent magnet in a radial direction relative to the axis of rotation and the second clamping element fixes it in a tangential direction relative to the axis of rotation, and wherein in each case a movement clearance is provided for each second clamping element. The present invention also relates to a clamping lamella, in particular for such a spoke rotor. The present invention also relates to an electric machine comprising such a spoke rotor. The present invention also relates to a device, in particular a hand-held power tool, an adjustment drive for a motor vehicle, a power steering system, a servo motor, an electromechanical brake booster or a vehicle drive, comprising such an electric machine.

The invention discloses a position detecting device and a signal processing device and method thereof. The position detecting device comprises a rotor and a stator covering the rotor inside, wherein the rotor comprises a first magnetic steel ring and a second magnetic steel ring which are fixed on a rotation axis; n-numbered magnetic induction elements which are uniformly distributed and correspond to the second magnetic steel ring, and m-numbered magnetic induction elements which are distributed at a certain angle and correspond to the first magnetic steel ring are arranged on the stator; and when the rotor carries out rotational motion relative to the stator, the magnetic induction elements convert the sensed magnetic signals into voltage signals and output the voltage signals to the signal processing device. In the invention, the magnetic induction elements fixed on the circumference of the stator are utilized to induce magnetic filed intensity variation caused by rotation of the magnetic steel fixed on the axis to output the voltage signals, and the voltage value is used for judging the rotation angle of the axis, thus realizing position detection. The invention has the advantages of quick response, high processing precision, low cost, simple manufacturing process, etc.

The invention relates to a fixing structure of a permanent magnet generator or a motor permanent magnet. The fixing structure comprises a rotor cylinder and permanent magnets, wherein the permanent magnets are arranged along the circumference of the surface of the rotor cylinder at intervals. Pole shoes are arranged among the permanent magnets along the circumference of the surface of the rotor cylinder and are used for fixing the permanent magnets, and a protruding part for clamping tightly the permanent magnets on two sides is respectively arranged on two side surfaces of each pole shoe. Each permanent magnet is fixed on the surface of the rotor cylinder by virtue of adjacent pole shoes on the two sides of each permanent magnet. According to the invention, the problem that the fixation of a current generator permanent magnet is not firm and consumes time and labors is effectively solved, the air gaps between the rotor and the stator can be reduced and the working efficiency of the generator is improved.

Provided is test equipment for electromagnetic immunity to interference. The test equipment for the electromagnetic immunity to interference comprises a support part, an induction coil and an instrument container, wherein the instrument container is connected with the induction coil in an electrical mode, the support part comprises a carrier block and a support, a clamping groove used for carrying a body of a gauss meter is formed in at least one side face of the carrier block, the induction coil comprises an annual coil and a connector used for mounting the annual coil on the carrier block, the support is mounted on the connector and extends into the annual coil along the radial direction of the annual coil, and the tail end of the support carries a probe of the gauss meter and can be adjusted to any position between the center position of the annual coil and the connector.

The invention discloses an omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer, wherein the transducer comprises a cylindrical neodymium-iron-boron magnet, a magnetic concentrator and a circular array type back-folding line ring. The multi-cluster circular zigzag line ring in a flexible circuit board is placed on the surface of an aluminum plate to be detected,and the magnetic concentrator and the neodymium-iron-boron magnet are attracted and then placed right above a return line ring. Based on lorentz force effect, the stimulating of omni-directional S0 modal guided wave in a plate structure is realized. Experiments verify that the prepared array type omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can be usedfor stimulating a single S0 mode guided wave in the aluminum plate; with an omni-directional test experiment carried out, the developed omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can stimulate to a S0 guide wave spread in the 360-degree direction; and a defect detection experiment verifies that the omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can effectively reduce the analysis difficulties and errors of defect signals.

The invention relates to a magnetic powder flaw detection device which comprises furcated current coils distributed on the positions of two end faces of a detected workpiece; the detected workpiece shows a two-surface surrounded shape by the furcated current coils; each furcated current coils in the positions of the end faces of the detected workpiece consist of a plurality of conductor wires which are radial from center to outside; the furcated current coils in the positions of the left end face and the right end face are fixed on two permanent seats of flaw detection equipment; two permanent seats can relatively move; the furcated current coils in the positions of the left end face and the right end face are connected through a wire connecting terminal which can be opened and closed; and when the wire connecting terminal is closed, the furcated current coils are connected to form a current passage. The magnetic powder flaw detection device overcomes the disadvantages of a rod-threading method in detecting a large-scale annular, disc or hollow workpiece, has an ideal magnetizing effect and an accurate and reliable detection result, and is suitable for batch detection, in particular for the detection of the annular, disc or hollow workpiece with large difference between inside diameter and outside diameter.

The invention relates to a coil structure of a wireless electric energy transmission system and especially relates to a wireless electric energy transmission system based on magnetic resonance coupling. A structure core is that magnetic field distribution of an electric energy receiving end is uniform and an auxiliary coil can receive a part of magnetic field which is scattered around a main coilso that losses can be reduced and partial overheating of a magnetic core can be restrained. In a structure of the whole wireless electric energy transmission system, losses of a coupling coil portionoccupy a large portion of losses of the whole system. By using the coil structure, the losses can be greatly reduced and transmission efficiency of wireless electric energy is increased.

The invention provides a permanent magnet synchronous motor rotor integration stamped sheet used for an oil-field oil pumper, comprising magnetic pole pieces and a magnetic steel tank, wherein the magnetic pole pieces are arranged into an integration structure along the periphery of motor revolving shaft hole, a magnetic steel mounting hole is arranged between each two adjacent magnetic pole pieces, a circle of conducting bar holes used for casting and starting mouse cage conducting bars and end rings at the outer ring of the magnetic pole pieces, and after a plurality of rotor stamped sheetsare overlapped and pressed, a channel with two ends open, namely the magnetic steel tank is formed by the magnetic steel holes. The invention eliminates the phenomenon of unbalanced rotor caused by assembling error of the original plural independent magnetic pole pieces, reduces vibration of the motor in operation, eliminates the problem of uneven width of the original magnetic steel tank, and improves work efficiency of magnetic steel assembling; the distribution of magnetic steel tank and magnetic pole pieces are even, and the motor operation is more stable; as the rotor stamped sheets forman integration structure, thus reducing production cost and labor intensity and greatly improving productivity.

The invention discloses a single loudspeaker and a production method of the single loudspeaker. The single loudspeaker comprises a magnetic cover, a magnet and a washer which are arranged in sequence. The centers of the magnetic cover, the magnet and the washer are provided with holes. The holes are consistent in shape and size. A fixed column is arranged in the single loudspeaker. The shape of the fixed column is matched with the shapes of the holes. The magnetic cover, the magnet and the washer sleeve the fixed column and are concentrically fixed together by the fixed column. Through arrangement of the holes at the centers of the magnetic cover, the magnet and the washer of the single loudspeaker, the magnetic cover, the magnet and the washer are brought together in a penetrating manner by the fixed column which is matched with the holes in shape. The magnetic cover, the magnet and the washer are firmly fixed together on the premise of ensuring the concentricity of the magnetic cover, the magnet and the washer. According to the single loudspeaker with such a structural design, distribution of the magnetic field generated by a magnetic circuit system is uniform, a high-quality sound effect is provided, the magnetic circuit system is fixed through adoption of the fixed column, therefore, the strength is relatively high, the reliability is high, and the service life of the product can be improved.

A magnetic Fe3O4 nano-particle / flake aluminium pigment composite nanometer material is disclosed. The composite nanometer material is prepared by in-situ synthesis of Fe3O4 nano-particles on surfaces of flake aluminium particles by a high-temperature oil phase method. A preparation process is green, safe, and free of pollution to the environment. According to the composite nanometer material, when the composite nanometer material is added into a pigment matrix, the Fe3O4 nano-particles are uniformly distributed in the pigment matrix and are not liable to agglomerate, and distribution of a magnetic field is more uniform.

The invention provides a variable frequency speed regulating disk type motor which uses sinusoidal windings and is in a double-layered type. Through interactive compensation action of two coils in each electrode of two main windings, the electrodes are sequentially connected, a magnetic filed is made to be distributed more evenly, the waveform is close to the sine wave, and declining of torque can not happen any more at a low rotating speed. Meanwhile, in the starting process, an auxiliary winding is connected with an operating capacitor and a starting capacitor, in the operating process, the auxiliary winding and the operating capacitor are connected, and startability and overload capacity are guaranteed. Meanwhile, through switching of the connecting mode of a high voltage and a low voltage, when the motor works in the high voltage of 200V-240V, the first main winding and the second main winding are in parallel connection with an auxiliary winding circuit after being in series connection, and when the motor works in the low voltage of 100V-120V, the first main winding, the second main winding and the auxiliary winding circuit are in mutual parallel connection. The variable frequency speed regulating disk type motor meets the operating demands in different rotating speed range under a general voltage condition in the global range. In addition, integration of the motor and a pump is achieved when the variable frequency speed regulating disk type motor is applied to a vacuum pump.

The invention discloses a low-energy-consumption method for separating ilmenites from tailings in an iron choosing plant. The method comprises the following steps: firstly, by taking the tailings in the iron choosing plant as raw materials, separating the tailings by using a permanent magnet drum-type mediate-intensity magnetic separator; discharging non-magnetic materials directly taken as magnetic separation tailings; next, grinding mediate magnetic separation concentrates taken as magnetic materials under the conditions that the monomer separation of the ilmenites is effectively realized while the grinding concentrates, the fineness of which is controlled as -75mu m, account for 75% to 95%; performing low-intensity magnetic separation on the mediate magnetic separation concentrates by using a low-intensity magnetic separator so as to separate iron concentrates and lead the rest of mineral materials to enter the next step; performing rough separation on the rest of mineral materials and then performing fine separation on the concentrates for multiple times after the rough separation so as to obtain ilmenite concentrates; performing sweeping separation on the tailings after the rough separation; combining the useful mineral materials for multiple times after the sweeping separation; returning the tailings after the fine separation into a rough separation process; and finally discharging the tailings which are subjected to the sweeping separation are taken as the ilmenites. The method is simple in process, reasonable in magnetic path design, uniform in magnetic field distribution, high in metal recovery rate and good in separation quality.

The invention discloses a low-field nuclear magnetic resonance probe magnet structure with a magnetic field switch function, comprising an outer ring magnet (1) and an inner ring magnet (2), and the outer ring magnet (1) is sheathed outside the inner ring magnet (2) . The outer ring magnet and the inner ring magnet of the low-field nuclear magnetic resonance probe magnet structure with the magnetic field switching function generate the same uniform magnetic field distribution inside the probe. During NMR measurement, after the static magnetic fields of the outer ring magnet and the inner ring magnet are superimposed on each other, they are equal to the magnetic field strength required by the design; when the measurement ends or the static magnetic field needs to be temporarily "turned off", the outer ring magnet is driven by the motor Rotate 180 degrees. At this time, the magnetic field strength generated by the inner and outer ring magnets is the same, but the direction is opposite, thus canceling each other out. At this time, the sample entering the magnetic field will no longer be magnetized.

The invention discloses a compact cycloidal wheel magnetorheological coupling. The compact cycloidal wheel magnetorheological coupling is composed of an outer rotary component and an inner rotary component. An outer sleeve is formed by fixedly connecting a magnetizer and magnetism isolating rings which are symmetrically distributed on the two sides in the axial direction, and a multi-turn electromagnetic coil is wound in an annular groove of the outer sleeve. An outgoing line of the electromagnetic coil and a wiring terminal are guided out from the axial side face of an input-end coupling and connected with a power supply slip ring, and the input end is sleeved with the power supply slip ring. The outer-diameter portion of the outer sleeved is sleeved with cooling fins, and the two ends of the outer sleeve are connected with the input end of the coupling and a transparent cover through magnetism isolating screws. Oil injection plug screws are symmetrically distributed and mounted on the axial outer-diameter portion of the transparent cover. Pressure release valves which are symmetrically distributed are mounted at the input-end coupling in the circumferential direction. An outer cycloidal wheel sleeve is formed by fixedly connecting a cycloidal wheel and an inner magnetism isolating ring and is of a hollow barrel-shaped structure, and the two ends of the outer cycloidal wheel sleeve are connected with a rotary flange and an output-end coupling through magnetism-isolating stainless steel screws correspondingly. The inner rotary component and the outer rotary component are connected through a bearing. The compact cycloidal wheel magnetorheological coupling has the advantages of being compact in structure, low in manufacturing cost, convenient to maintain, and capable of transmitting a large torque.

The invention discloses a 5-point generatrix configuration method of a large-area inequipotential electricity type. It is composed of the cathode soft generatrix, cathode generatrix, bottom generatrix, side generatrix, lower column generatrix and electrobath. The lower column generatrix is 5-piece configuration. The invention not only can make the current passing every column appropriate and effectively reduce the magnetic field in the slot and the transverse magnetic field, but also match with every slot paramete of the large-scale slot. Especially compared with the two columns, the center columune has low current and is benefit to reduce the danger caused by the middle level magnetic field in the electrobath to make the electrobath more stable.

The invention provides a magnetron assembly and magnetron sputtering equipment. The magnetron assembly comprises a center permanent magnet and annular permanent magnets surrounding the center permanent magnet. The polarity of the center permanent magnet is opposite to that of the annular permanent magnets. The annular permanent magnets are of an integrated structure. According to the magnetron assembly provided by the invention, installing is convenient and safe, the distribution uniformity of outer ring magnetic fields can further be improved, the higher magnetic field intensity is achieved under the condition of the same-size outer ring magnets, and thus the higher power density can be obtained under the condition that the effect that the magnetic field intensity is not decreased is ensured.