170 results about "Low magnetic field" patented technology

The invention belongs to the field of magnetic refrigeration materials, and particularly discloses a gadolinium-based molybdate magnetic refrigeration material and a preparation method and application thereof. The gadolinium-based molybdate magnetic refrigeration material comprises GdXMoO4, wherein X is F, Cl, Br or I; the magnetic phase change temperature of the gadolinium-based molybdate magnetic refrigeration material is less than 2K, and the maximum magnetic entropy change of the gadolinium-based molybdate magnetic refrigeration material is greater than or equal to 12J. Kg <-1 >. K <-1 > when the magnetic field change is 0-50kOe. The gadolinium-based molybdate magnetic refrigeration material disclosed by the invention has extremely low magnetic phase transition temperature, has relatively high magnetocaloric efficiency in a low magnetic field, is an extremely low temperature region magnetic refrigeration material with excellent performance, and has a wide application prospect in the field of extremely low temperature magnetic refrigeration.

The present application is drawn to a system and method, as well as method for manufacture of a device and system for determining the position and orientation of at least one magnetic field sensor comprising: a rigid structure comprising an array of at least five electromagnetic coils; at least one wire that connects to and powers the electromagnetic coils; wherein the placement and orientation of the electromagnetic coils on the rigid structure are predetermined; wherein the electromagnetic coils, each having a predefined magnetic moment per unit current, are constructed with a printed circuit board (PCB) comprising at least one conductive layer; and wherein the system is configured such that a stray magnetic field emanating from the at least one, as measured at the location of the at least one magnetic field sensor, generates substantially lower magnetic field intensity than that produced by each of the at least five electromagnetic coils.

A magnetic orbital angular momentum beam accelerator will accelerate charged particles, electrons or ions, from rest in zero or low magnetic field into a high magnetic field regions with high kinetic energies in the form of magnetic orbital angular momentum. For example, a beam injector that accelerates electrons or ions into 1T magnetic fields with tens of keV kinetic energies transverse to the magnetic fields can be used to heat magnetically confined plasmas, to inject an initial energetic plasma component with high magnetic orbital angular momentum and to produce highly transverse particle momenta to the magnetic field for electron or ion beam lithography.

The invention relates to a Fe-Si-Nb-B-Cu-Er amorphous alloy and a preparation method and application thereof, and belongs to the technical field of metal materials. The atomic percent expression of the Fe-Si-Nb-B-Cu-Er amorphous alloy disclosed by the invention is (Fe < 83 > Si < 3 > Nb < 4 > B < 9 > Cu < 1 >) < 100-x > Er < x >, wherein x is equal to 3.5 to 4.5. The rare earth element Er is added to optimize the soft magnetic performance of a Fe-Si-Nb-B-Cu amorphous alloy system, the coercive force of the Fe-Si-Nb-B-Cu amorphous alloy system is reduced, the preparation method is simple and easy to implement, and the Fe-based amorphous alloy with the excellent soft magnetization performance is obtained. The magnetization intensity of the amorphous alloy is sharply increased along with increase of a magnetic field under a low magnetic field and then gradually reaches saturation, typical soft magnetic performance is presented, and the amorphous alloy has wide application space in the field of magnetic materials.

The invention belongs to the field of magnetic materials, and particularly discloses europium-based silicate as well as a preparation method and application thereof. The general chemical formula of the europium-based silicate is Eu2SiO4, and the europium-based silicate is subjected to secondary magnetic phase change from a paramagnetic state to a ferromagnetic state at the magnetic phase change temperature of 5.8 K; and at the temperature of 5.5 K, when the magnetic field change is 0-2T, the maximum magnetic entropy change is greater than 10J. Kg <-1 >. K <-1 >. The europium-based silicate disclosed by the invention generates paramagnetic to ferromagnetic phase change near the liquid helium temperature, is accompanied by a low-magnetic-field giant magnetothermal effect near the magnetic phase change temperature, shows large magnetic entropy change and refrigerating capacity near the liquid helium temperature, and has a wide application prospect in the field of magnetic refrigeration in a liquid helium temperature region.

The embodiment of the invention discloses a scanning NV probe microscope which comprises an atomic force microscopy system used for detecting surface topography information of a sample and an optical detection magnetic resonance system used for detecting surface magnetic field distribution information of the sample, and the atomic force microscopy system comprises a vibration arm and a diamond probe. The optical detection magnetic resonance system comprises an NV color center, a transition excitation light path and a fluorescence detection light path; a sample to be scanned and the transition excitation light path are respectively positioned on two opposite sides of the diamond probe, and the transition excitation light path and the fluorescence detection light path are positioned on the same side of the diamond probe; a first metal coating film is arranged on one side, close to the sample, of the diamond probe and is used for blocking surface fluorescence of the sample. According to the scanning NV probe microscope provided by the embodiment of the invention, the metal coating is arranged at the bottom of the diamond probe to block stray fluorescence from the surface of the sample, so that the problems of low magnetic field imaging signal-to-noise ratio and limited measurement precision of the existing scanning NV probe microscope are solved.

The invention provides a 90-degree Halbach array-based magnetic coupler for a reaction kettle, which comprises a sealing cover cylinder, an outer magnet support sleeve is rotatably connected to the outer side of the sealing cover cylinder, a plurality of outer magnets are arranged on the outer magnet support sleeve, an inner magnet support sleeve is rotatably connected to the inner part of the sealing cover cylinder, and a plurality of outer magnets are arranged on the inner magnet support sleeve. A plurality of outer magnets are arranged on the outer magnet supporting sleeve, a plurality of inner magnets are arranged on the inner magnet supporting sleeve, the outer magnets and the inner magnets are arranged according to a 90-degree Halbach array, the outer magnets are arrayed according to the fact that the magnetic induction intensity of the inner sides of the outer magnets is enhanced by the 90-degree Halbach array, and the inner magnets are arrayed according to the fact that the magnetic induction intensity of the outer sides of the inner magnets is enhanced by the 90-degree Halbach array. The invention further provides an optimal design method of the magnetic coupler, and an optimal design combination is found by adopting a multi-target parameterization optimal design method. The invention solves the technical problems of low magnetic field intensity between air gaps, low magnetic steel utilization rate, low maximum transmission torque and low design and development method efficiency of the existing magnetic coupler, and belongs to the technical field of magnetic drive reaction kettles.

The invention discloses a magnetic field chip design method based on a genetic algorithm, and the method comprises the steps: setting genetic algorithm parameters, and setting magnetic field chip target parameters according to actual application demands; generating an initial population, wherein the initial population is a plurality of groups of individuals containing coil parameters; checking constraint conditions of the individuals, wherein the constraint conditions comprise physical constraints and design constraints; the power consumption generated by the coil structures corresponding to the individuals meeting the constraint conditions serves as a fitness function, and the fitness of all the individuals in the current population is evaluated; and judging whether a termination condition is met or not, outputting an individual with the optimal fitness as an optimal combination of coil parameters under the target parameters of the magnetic field chip when the termination condition is met, otherwise, generating a next-generation population, and repeatedly carrying out constraint condition check and fitness evaluation until the termination condition is met. According to the method, the magnetic field chip with the minimum power consumption meeting the magnetic field target can be designed, the design time of the magnetic field coil is greatly shortened, and the design rapidity and flexibility are improved.

The invention provides a preparation method of a low-interface thermal resistance carbon fiber composite material based on a low magnetic field orientation technology and carbon fiber orientation equipment. The preparation method comprises the following steps: performing surface modification on short carbon fibers by adopting a non-magnetic carbon fiber surface modifier; mixing and dispersing the surface-modified short carbon fiber, liquid silicone rubber and an auxiliary agent to obtain a carbon fiber composite material; calendaring the carbon fiber composite material to a specified thickness, coating the surface of a rotating table with the carbon fiber composite material for rotary orientation, and preliminarily adjusting the distribution of carbon fibers in the carbon fiber composite material; performing orientation arrangement on the carbon fibers in the carbon fiber composite material again by combining a gradient magnetic field lower than 1T with ultrasonic vibration, wherein the vibration direction of the ultrasonic vibration is consistent with the direction of the magnetic field; and carrying out heating curing molding on the oriented carbon fiber composite material to obtain the low-interface thermal resistance carbon fiber composite material. By regulating and controlling fiber arrangement in stages and combining ultrasonic vibration auxiliary dispersion, carbon fiber dominant direction arrangement is effectively achieved, and the magnetic field intensity requirement is lowered.

The invention belongs to the field of magnetic particle imaging, particularly relates to a zero-inertia magnetism gathering ring magnetic-field-free line magnetic particle imaging system and method, and aims to solve the problems of low magnetic field gradient, high magnetic field control complexity and limited imaging space. The current of a gradient magnetic field coil group is generated by a magnetic field control and imaging module, is output by a signal acquisition and output module, and is amplified and provided by a gradient power amplifier module. The current of the axial excitation magnetic field coil is generated by the magnetic field control and imaging module, is output by the signal acquisition and output module and is amplified and provided by the excitation power amplifier module, and a signal received by the multi-axis detection coil is filtered and amplified by the signal processing unit and then is input to the imaging module by the magnetic field control and imaging module for algorithm reconstruction. According to the invention, the magnetic field gradient and the control precision are obviously improved, and the imaging space of the axial fault plane is realized.

Winding grooves are formed in a stator iron core in the circumferential direction, the winding grooves comprise outer-layer stator grooves on the yoke portion side and inner-layer stator grooves on the side close to a permanent magnet rotor, harmonic windings are embedded in the outer-layer stator grooves, and the harmonic windings are double-layer short-pitch windings; a fundamental wave winding is embedded in the inner-layer stator slot, and the fundamental wave winding is a centralized winding; a plurality of modulation teeth are arranged in the stator iron core along the circumferential direction in a non-equidistant manner; the number pf of pole pairs of the fundamental wave winding is consistent with the number pf of pole pairs of the permanent magnet rotor, the number ph of pole pairs of the harmonic wave winding is different from the number pf of pole pairs of the fundamental wave winding, and the number Ns of poles of the modulation teeth meets the condition that Ns = pf + ph, Ns = (1 + 2n) ph or Ns = (1 + 3n) ph. The technical defects that a traditional permanent magnet motor cannot utilize harmonic waves and a conventional magnetic gear effect permanent magnet motor cannot efficiently utilize harmonic waves and fundamental waves to do work can be overcome, the torque density of the motor is greatly improved while the power factor is not degraded, and the complexity, the system cost and the additional loss of a magnetic field modulation structure are reduced.

The utility model discloses a submerged arc furnace cover capable of reducing magnetic field interference, which comprises a cover body, a plurality of groups of annularly distributed grounding plates are arranged on the cover body, a mounting frame is arranged on the cover body, a mounting rod is arranged in the mounting frame, a valve plate is sleeved on the mounting rod, the valve plate is movably clamped with the cover body, and the valve plate is connected with the cover body. The mounting rod is sleeved with a compression spring, an adjusting plate is sleeved with the mounting rod, a threaded rod is arranged in the mounting rod, the mounting frame is sleeved with a splash guard, the cover body is sleeved with a cooling water pipe, and the arranged valve plate is matched with the compression spring, the threaded rod and the adjusting rod to achieve overpressure protection of the furnace cover. Safety accidents such as damage to the furnace cover or the furnace body caused by too high pressure in the furnace body are avoided, protection of splashing of furnace charge in the furnace cover is achieved through the arranged splash-proof cover, and the furnace charge is prevented from splashing out to damage equipment or injure workers in the opening process of the valve clack.

The invention relates to a high-thermal-conductivity all-carbon-series heat-conducting gasket and a preparation method and application thereof, in particular to a high-thermal-conductivity all-carbon-series heat-conducting gasket based on a shearing force field and low magnetic field double-field orientation technology and a preparation method thereof, belongs to the technical field of preparation of electronic functional materials, and is mainly used for thermal management of high-power electronic components such as chips, LEDs and 5G equipment. The high-thermal-conductivity all-carbon-series heat-conducting gasket comprises the following raw materials in parts by weight: 100 parts of organic silica gel, 200-500 parts of pitch-based carbon fibers, 80-230 parts of spherical heat-conducting filler and 300-700 parts of a diluent, and the all-carbon-series heat-conducting gasket is oriented in the direction of a magnetic field by utilizing the synergistic effect of a shear force field and the magnetic field. The process has the characteristics of high production efficiency, low cost and easiness in industrial production, and can ensure that a highly-oriented and tightly-arranged heat-conducting network structure is formed in the composite material. The technical breakthrough is of great significance in promoting the practical application of the high-performance thermal interface material.

The invention discloses an energy recovery type electric tensioner and method for an overhead line, and relates to the technical field of overhead transmission line construction equipment. The tension control mechanism comprises a mounting frame, a first driving mechanism and a fine adjustment mechanism; wherein the mounting rack is connected to the rack in a sliding manner, and the cable is tensioned on the mounting rack; the first driving mechanism is mounted on the rack and is used for driving the mounting rack to slide on the rack so as to control the tension of the cable; the fine adjustment mechanism is installed on the installation frame and used for controlling the tensioning distance between the cable and the installation frame. By arranging the first driving mechanism and the fine adjustment mechanism, the precision of coarse adjustment and fine adjustment is superposed, and a pure mechanical tension control chain is adopted, so that the tension measurement error in a magnetic field is reduced, and the tension control precision is improved; a two-stage control system is formed through the first driving mechanism and the fine adjustment mechanism, and the tension adjusting range is guaranteed.

The invention discloses a room temperature magnetic heat pump control system and a control method, which are used for controlling the regenerative cycle operation process of a room temperature magnetic heat pump and comprise a power supply module, a sensor module, a single chip microcomputer, an actuator module and a serial port screen, the sensor module is used for collecting temperature, pressure, flow, liquid level, magnetic field position and motor operation state signals and transmitting the signals to the single-chip microcomputer. The serial port screen is connected with the single-chip microcomputer, displays and stores the signal data in real time, and sends a control signal to the single-chip microcomputer; the single-chip microcomputer receives signals of the sensor module and the serial port screen and then sends control signals to the actuator module, and closed-loop control over the room-temperature magnetic heat pump system is achieved. The single-chip microcomputer serves as a core controller to achieve automatic control and key parameter collection of the room temperature magnetic heat pump system, and it is ensured that the actual process is close to theoretical regenerative cycle through time sequence matching and parameter feedback; the problems that an existing room-temperature magnetic heat pump system is low in automation degree, low in magnetic field positioning precision, unbalanced in cold and hot flow and poor in controller following performance are solved.

The present application is drawn to a system and method, as well as method for manufacture of a device and system for determining the position and orientation of at least one magnetic field sensor comprising: a rigid structure comprising an array of at least five electromagnetic coils; at least one wire that connects to and powers the electromagnetic coils; wherein the placement and orientation of the electromagnetic coils on the rigid structure are predetermined; wherein the electromagnetic coils, each having a predefined magnetic moment per unit current, are constructed with a printed circuit board (PCB) comprising at least one conductive layer; and wherein the system is configured such that a stray magnetic field emanating from the at least one, as measured at the location of the at least one magnetic field sensor, generates substantially lower magnetic field intensity than that produced by each of the at least five electromagnetic coils.

The utility model relates to copper wire production technical field, concretely relates to a kind of copper wire production and processing's stretching device, including lubricating bucket and the conveying part for being immersed into the copper wire in lubricating bucket;Electromagnetic rod is located in lubricating bucket, it includes the sealing sleeve coaxially fixed in lubricating bucket and the electromagnetic coil coaxially located in sealing sleeve, for generating strong magnetic field and drive copper powder to the arc-shaped inner wall of lubricating bucket, fishing part is located in lubricating bucket, it includes the fishing ring coaxially slidingly located in lubricating bucket, the outer edge of the fishing ring contacts the inner wall of lubricating bucket.The utility model generates strong electromagnetic field by electromagnetic rod, since copper powder belongs to inverse magnetic material, it generates induced eddy current in alternating magnetic field, and then generates reverse magnetic field, forms repulsion with magnetic field source Lorentz magnetic force and is pushed to low magnetic field area by magnetic repulsion, copper powder can be pushed to the arc-shaped inner wall of lubricating bucket and gathered in real time, greatly extend the period of lubricating liquid cleaning or replacement, reduce its cleaning or replacement frequency.

A wearable device is disclosed. The wearable device may comprise: a speaker including a coil; a coin cell battery disposed on the speaker; and a conductive tab on a first surface of a case of the coin cell battery, the conductive tab being electrically connected to a portion of a first electrode positioned on the first surface of the case. The coin cell battery can include: the case that includes the first surface facing the speaker and a second surface opposite to the first surface; and a jelly roll. The conductive tab on the first surface of the case can extend in a second rotational direction opposite to the first rotational direction of the jelly roll so as not to overlap the coil of the speaker.

The invention provides a vehicle magnetic field interference shielding method, system and device, a storage medium and a product, and the method comprises the steps: measuring an interference magnetic field in a preset range of a magnetic field sensitive part through a three-axis magnetic sensor, and obtaining interference magnetic field data; wherein the interference magnetic field data comprises the intensity and the direction of the interference magnetic field; if the intensity of the interference magnetic field is greater than a preset safety intensity threshold value, controlling the magnetic field interference shielding device to generate an anti-interference magnetic field according to the interference magnetic field data so as to offset the interference magnetic field in a preset range of the magnetic field sensitive component; the direction of the anti-interference magnetic field is opposite to that of the interference magnetic field, and the intensity of the anti-interference magnetic field is consistent with that of the interference magnetic field. According to the scheme, the low-frequency strong magnetic field interference can be effectively eliminated while the magnetic field interference shielding cost is reduced, and the safety and reliability of the vehicle are improved.

The present invention belongs to the field of magnetic particle imaging, and specifically relates to a zero-inertia magnetic focusing ring magnetic particle imaging system and method without magnetic field lines, aiming to solve the problems of low magnetic field gradient, high complexity of magnetic field control, and limited imaging space. The present invention includes: the current of the gradient magnetic field coil group is generated by the magnetic field control and imaging module, output through the signal acquisition and output module, and amplified by the gradient power amplifier module. The current of the axial excitation magnetic field coil is generated by the magnetic field control and imaging module, output through the signal acquisition and output module, and amplified by the excitation power amplifier module. The signals received by the multi-axis detection coil are filtered and amplified by the signal processing unit, and then input to the imaging module by the magnetic field control and imaging module for algorithm reconstruction. The present invention not only significantly improves the magnetic field gradient and control accuracy, but also realizes the imaging space of the axial cross-section.

To provide a magnetic shield device for shielding magnetism from the outside, which maintains a low magnetic field environment in the magnetic shield device (magnetic shield space) and reduces a fluctuation amount of a magnetic field by suppressing temperature fluctuation of the magnetic shield device itself causing magnetic field fluctuation (maintaining temperature stability).SOLUTION: The magnetic shield device 1 includes two or more layers of magnetic shield members 11,12, a thermally conductive member 13 which can accommodate a magnetic sensor and a test object therein, is disposed outside the innermost magnetic shield member 11, and is in thermal contact with substantially the entire surface of the innermost magnetic shield member 11, and a thermally conductive member temperature stabilizing means (here, a constant-temperature fluid 14, a constant-temperature fluid passage 15, a constant-temperature fluid delivery function, and a heat insulating layer 19) for maintaining the thermally conductive member 13 at a constant temperature.SELECTED DRAWING: Figure 2

The invention relates to the technical field of rheological testing and material characterization, and provides a local rheological testing system and device based on electromagnetic driving and visual displacement tracking, and the system comprises a magnetic field generation module which is used for generating a stable magnetic field for magnetizing a magnetic needle in a sample area and a periodic gradient magnetic field for driving the magnetic needle, and a driving module, the magnetic field generation module is used for providing corresponding steady-state and alternating current excitation for the magnetic field generation module, and the image acquisition module is used for generating a uniform linear magnetic field gradient in a central area by a gradient field Maxwell configuration coil pair and an external trigger synchronization mechanism through the arrangement of the structures such as the gradient field Maxwell configuration coil pair and the external trigger synchronization mechanism; the driving force acting on the magnetic needle is ensured to be stable and repeatable; an external trigger synchronization mechanism controls driving signals to be strictly synchronized with image acquisition, and magnetic needle displacement and phase difference are accurately extracted by combining image recognition and a sub-pixel positioning algorithm, so that magnetic field fluctuation and time sequence errors are effectively reduced, the rheological parameter inversion precision is improved, and the problems of large errors and high cost in the prior art are solved.

The invention relates to the technical field of magnetron sputtering equipment, in particular to a space type magnetic field assembly, an annular rotating cathode and magnetron sputtering coating equipment. At least four magnet base bodies are arranged, the space layout adjacent to the inner ring of a cooling pipeline is adopted, and at least one of the following adjustments is made on the end portions of the two ends of each magnet base body; the method comprises the following steps of: 1, adjusting, wherein the shape of the end part of the magnet base body is different from that of the middle part of the magnet base body; adjusting II, wherein the magnetizing process of the end part of the magnet base body is different from the magnetizing process of the middle part of the magnet base body; and 3, the magnet base body is sleeved with a magnet sleeve, the magnet sleeve at the end of the magnet base body is made of a gradient functional material, the magnetic conductivity difference of the material is utilized, on one hand, local etching of the end area of the target material is optimized, the utilization rate of the target material is increased, and on the other hand, the magnet sleeve abuts against the inner ring of the cooling pipeline, and magnetic field intensity attenuation is reduced.

The invention provides a neodymium iron boron magnet and a preparation method thereof. The method comprises the following steps: obtaining neodymium iron boron magnetic powder; the neodymium iron boron magnetic powder is put into the mold, and the neodymium iron boron magnetic powder is in a loose loading state in the mold; applying an alternating-current oscillation attenuation magnetic field to the neodymium-iron-boron magnetic powder in the mold; orientation profiling is conducted in a preset orientation static magnetic field, a pressed blank is obtained, and the magnetic field direction of the preset orientation static magnetic field is perpendicular to the magnetic field direction of the alternating-current oscillation attenuation magnetic field; and post-processing the pressed blank to obtain the neodymium-iron-boron magnet. The magnetic field is attenuated through alternating-current oscillation, the magnetic field direction is perpendicular to the static magnetic field direction, agglomeration of the magnetic powder can be scattered, and meanwhile the influence of non-parallel magnetic lines of the magnetic field on magnetic powder orientation can be reduced.

The invention provides a three-phase electromagnetic coupling mechanism and a wireless power transmission system, and relates to the technical field of wireless power transmission. The three-phase electromagnetic coupling mechanism comprises a magnetic core layer, an A-phase coil, a B-phase coil and a C-phase coil, wherein the A-phase coil, the B-phase coil and the C-phase coil are arranged on the magnetic core layer in a stacked mode and form a three-layer stacked structure. The A-phase coil, the B-phase coil and the C-phase coil respectively comprise two coil sections which are electrically connected, each coil section covers a 180-degree corresponding area in the circumferential direction of the magnetic core layer, and orthographic projections of the two coil sections of each phase coil on the magnetic core layer are in central symmetry; and each layer of the three-layer laminated structure is provided with coil parts of coil sections of at least two different-phase coils. Multi-layer participation and symmetrical coverage of the three-phase coils are realized in the three-layer laminated structure, and each layer comprises different-phase coil sections, so that the problems of low space utilization rate and non-uniform magnetic field of a planar structure are effectively solved, and the magnetic coupling stability and the power transmission performance are improved.

A design method for a double-layer, double-plane self-shielded coil significantly reduces magnetic field crosstalk and shielding barrel coupling effects, improving magnetic field stability and space utilization. It is suitable for coil design and integration applications in high-precision magnetic field control systems. A target field model is established based on the target magnetic field distribution, and magnetic flux constraints ensure that the external magnetic field of the coil approaches zero, thus achieving self-shielding characteristics. Subsequently, a stream function discretization method is used to obtain the coil winding path, and a mapping relationship and current scaling factor between the inner and outer coil layers are established to ensure that the double-layer coil effectively cancels out the external magnetic field while generating the target magnetic field. To further optimize magnetic field uniformity and energy distribution, this invention introduces a tornado optimization algorithm for global optimization of the coil distribution, thereby obtaining a coil structure with high uniformity and high attenuation performance. Finally, finite element simulation is performed on the coil shape to analyze whether its uniformity and attenuation meet the design requirements.

The utility model discloses a differential driving type loudspeaker with inner and outer sets of magnetic circuits and a sound box. Wherein the differential driving type loudspeaker with the inner and outer sets of magnetic circuits comprises an inner side upper washer, an inner side upper magnet arranged below the inner side upper washer, an inner side magnetic conductive column arranged below the inner side upper magnet, an inner side lower magnet arranged below the inner side magnetic conductive column, and an inner side lower washer arranged below the inner side lower magnet; the voice coil is sleeved on the outer end surfaces of the inner side upper washer and the inner side lower washer; the magnetic flux ring is sleeved on the outer end surface of the voice coil; the outer side upper washer is sleeved on the outer side of the upper part of the voice coil; the outer side upper magnet is arranged below the outer side upper washer; the outer side lower magnet is arranged below the outer side magnetic conductive column; and the outer side lower washer is arranged below the outer side lower magnet. The magnetic field sensor has the beneficial effects of light weight, low energy consumption, high magnetic field intensity and high sensitivity.

The invention discloses a shot blasting, sorting, cleaning and recycling system. Steel shots, oxide skin and dust are separated through a stirring kettle by means of flowing of a liquid medium. An electromagnetic module attached to the side wall of the kettle body is arranged outside the kettle body, the magnetic field of the electromagnetic module is changed through a current control module, and gradient magnetic attraction is generated to enable steel shots, oxide skin and dust to be mixed with liquid in sequence and discharged; the invention further discloses a shot blasting, sorting, cleaning and recycling method. The method comprises the steps of liquid mixing and stirring (enabling dust, steel shots and oxide skin to be preliminarily dispersed), gradient magnetic attraction (enabling a high-intensity magnetic field to attract the steel shots and enabling a medium-intensity magnetic field to attract the oxide skin) and step-by-step impurity removal (firstly removing non-magnetic dust liquid, then enabling the oxide skin to be separated and discharged by lowering the magnetic field, and finally achieving thorough separation of the steel shots and the impurities). And dust, oxide skin and steel shots in waste materials generated by shot blasting are effectively separated.

The invention discloses a rotor structure for fixing a magnet by using a magnetic pole box, relates to the technical field of motor rotors, and aims to solve the problems of poor fixing reliability, inconvenience in installation and adjustment and high maintenance cost of a permanent magnet in the prior art. The top of the rotor support is provided with a rotor iron core, and the bottom end of the annular inner wall of the rotor iron core is connected with symmetrically-distributed pull rods in an inserted mode. The fixing device is reliable in fixing and high in stability, the problem that a permanent magnet of a traditional structure is not reliable in fixing is solved through a multi-stage positioning and elastic pressing structure, rigid supporting is formed by the pull rod and the fastening assembly, circumferential positioning is achieved through cooperation of the check block and the groove, and axial elastic pressing is formed by the limiting ring and the pressing block; triple fixation enables the permanent magnet not to loosen and fall off at a high rotating speed, the rubber pressing block buffers pressure, the fragmentation rate of the permanent magnet is reduced, the distribution uniformity of a magnetic field is improved, the vibration noise of the motor is reduced, and the operation stability is remarkably improved.

Provided is a vehicle that, in order to promote the safety of a user having an active implantable medical device implanted therein, is configured to acquire a strength of a magnetic field inside the vehicle, notify the user of the strength of the magnetic field, and control at least one electric device among a plurality of electric devices in the vehicle, in order to reduce the strength of the magnetic field. The vehicle may be a combustion engine vehicle and / or an electric vehicle.