1458 results about "Magnetic leakage" patented technology

A first object of the present invention resides in providing a novel installation structure for an RFID tag, which effectively protects the RFID tag from external stress or impact during the storage, transportation and usage, and allows communication with the external.A second object of the present invention resides in that providing a novel installation structure for an RFID tag, which enables communication with the external even if the RFID tag is installed on a conductive member such as a metal member, and the surface thereof is covered with a protective member typically made of a metal which has an excellent strength and durability.A third object of the present invention is to provide a communication method using an RFID tag as being surrounded by a conductive member typically made of a metal.Even if an RFID tag 1a is housed in a container A typically made of a conductive material such as a metal having a large mechanical strength, the RFID tag 1a can communicate with an external read / write terminal 9 as mediated by leakage magnetic flux if only a flux leakage path 12 composed for example of a gap is formed in such container A.

An improved structure of inductance core and wire frame mainly provides a center post at the center portion of the core. A containing circumferential channel is also provided at the periphery of the center post to make the outer circumference of the containing circumferential channel form a surrounded circumferential side wall that has small area of indentation openings at the end corners only. A center hole is also provided at the center portion of the wire frame that accommodates the center post, and a bobbin for the winding of the coil is further provided at the outer circumference of the center hole. A salient lead-out seat is provided at the end corner of the wire frame, and brazing posts are also provided on the same side at the upper edge of each of the lead-out seat to connect to the drawing head of the coil. By the use of the center post of the core embedding into the center hole of the wire frame, as well as making use of the containing circumferential channel to contain the wire frame, each of the lead-out seat of the wire frame can stretch out through the openings of the core. The magnetic leakage can be lessened and the inductance efficiency can be improved by making use of the circumferential side wall to form an integral surrounded covering.

The disclosed detector comprises: a driver, a magnetic-leakage probe, a magnetic-leakage signal process device with a rotary coder, a power, an ultrasonic probe, and a ultrasonic signal processor with a roller carried a milometer all connected by gimbals in turn. This invention integrates both magnetic-leakage and ultrasound, realizes precise positioning to defect in pipeline, and can detect the defect and hidden danger all round.

The invention discloses a permanent magnetic speed regulation, brake or load apparatus capable of stepless adjustment of magnetic field intensity. The apparatus is characterized in that the apparatus is a of single-rotating disk / multi-rotating disk type structure , a single-rotating cylinder / multi-rotating cylinder type structure, a rotating disk and rotating cylinder combination type structure or a rotating disk and rotating cylinder compound structure, and is mainly composed of a driving rotor, a driven rotor, a work magnetic coupling air gap / medium, a magnetic leakage magnetic circuit / air gap, a magnetic leakage magnetic circuit air gap adjusting disc and an adjusting mechanism. The apparatus provided by the invention is applied to such technical fields as coupling transmission, load speed regulation, automatic transmission, brake and braking, load rotation, power cut-off / combination, motor energy conservation, a household electrical appliance (including an air conditioner, an electric fan and a washing machine) and the like. The technical scheme is used for designing and manufacturing a permanent magnetic speed regulator, a speed regulation shaft coupling, an automatic transmission, a braking device, a load / loading device, a centrifugation load speed regulator or a clutch or a novel energy-saving household electrical appliance.

The invention relates to a device and a method for detecting defects of inner and outer walls of a pipeline based on three-axis magnetic flux leakage and eddy current, and belongs to the technical field of non-destructive testing. The device comprises a magnetic flux leakage detector, a data processing and storing device, a power supply, at least three odometer wheels and an eddy current detector, wherein the eddy current detector consists of an eddy current sensor and is a device used for detecting the defects on inner and outer surfaces of the pipeline. According to the device provided by the invention, a magnetic flux leakage detection method and an eddy current detection method are combined by using different characteristics of the magnetic flux leakage detection method and the eddy current detection method, so that the function of distinguishing the defect of the inner wall from the defects of the outer wall is realized; and in addition, the method provided by the invention is favorable in detection quality and simple in operation and can be widely applied to non-destructive detection of oil transmission pipelines in the industrial fields of petroleum, petrifaction and the like.

The wire rope detection method based on 3D leakage magnetic field comprises: acquiring the defect sample magnetic leakage signal by Hall sensor array; eliminating trough by an adaptive space trapping filter; taking normalization and K-L transformation to extract feature and train NN, and detecting the real defect by the network. The corresponding detection device comprises: a sensor probe included a permanent magnet excitation part and an analog switch and a photoelectric encoder, a data acquirement processor, and a computer. This invention can provide full defect signal and improve detection precision.

The invention provides a 12-pulse converter comprising an autotransformer having a primary winding connected in a delta configuration and two secondary windings connected in star configurations, the two secondary windings being connected to two rectifier bridges that are enabled to operate in parallel by two interphase chokes, the converter further comprising means for generating an additional magnetic leakage flux in at least one of the interphase chokes so as to incorporate a smoothing choke therein.

The invention discloses a sweeping robot obstacle avoiding and positioning system and method. Collision detection is composed of nine sections. A direction detecting assembly is a three-axis magnetoresistive sensor. The outer surfaces of all motors are covered with magnetic shielding assemblies. A distance detecting assembly comprises a multi-pole magnetic ring (16) and a Hall sensor (17). The outer wall of the multi-pole magnetic ring (16) is covered with a magnetic shielding layer (18). A semi-circular front cover of a sweeping robot is divided into the nine sections to carry out collision detection, and the collision position can be accurately and specifically recognized. Direction detection is achieved through the three-axis magnetoresistive sensor, the structure is simple, cost is low, the motors are tightly covered with the magnetic shielding assemblies, and the leakage flux interference of the motors is further reduced. Distance measuring is achieved through the cooperation of the Hall sensor and universal wheels, the structure is simple, cost is low, strict magnetic shielding is adopted, the leakage flux interference of the motors is effectively avoided, a magnetic field produced on the multi-pole magnetic ring can be restrained within the radial range of Hall sensor detection through the magnetic shielding layer of the multi-pole magnetic ring, and the distance measuring accuracy is high.

An apparatus that reduces vibration generation and magnetic leakage, wherein the apparatus is a motor, an articulated serial robot that has a motor built in, a substrate loader that includes the articulated robot, and a related exposure apparatus equipped with the substrate loader. The motor includes a drive shaft to drive the motor; a rotor attached with the shaft; and a stator that opposes the rotor and causes an electromagnetic force to act between the rotor and the stator to drive the drive shaft; an RC stator, for reaction force cancellation attached with the stator; an RC rotor for reaction force cancellation, opposing the RC stator; and a counterweight sleeve attached with the RC rotor, wherein the reaction force, which is applied to the stator via the drive shaft when the counterweight sleeve rotates in a direction opposite that of the drive shaft, is cancelled.

The invention provides an intelligent analysis system and method for magnetic flux leakage detection data in a pipeline. The process comprises the following steps: adopting time domain-based sparse sampling and KNN-softmax data complete set construction module, obtaining a complete magnetic flux leakage data set; a pipeline connection assembly discovery method based on combination of selective search and a convolutional neural network is adopted in the discovery module to obtain the accurate position of the weld joint; adopting an abnormal candidate region searching and identifying method based on a Lagrangian multiplication frame and multi-source magnetic flux leakage data fusion in the discovery model to find out defective magnetic flux leakage signals; Adopting a defect quantification method based on a random forest in a quantification module to obtain a defect size; a pipeline solution improved based on the ASME B31G standard is adopted in the solution module, and an evaluation result is output. An analysis method is provided from the overall perspective, and pretreatment, connection assembly detection and abnormity detection, defect size inversion and final maintenance decision are achieved.

The device for magnetically suspending a rotor relative to a structure comprises at least one axial active magnetic bearing with a main electromagnet coil disposed in a stator and having load-bearing surfaces placed facing an armature extending essentially perpendicularly to the axis of the rotor. A device for detecting the axial position of the rotor is associated with circuits for servo-controlling the current carried by the main electromagnet coil. A compensation coil is disposed close to the main electromagnet coil, but in a position that is situated away from the load-bearing surfaces of the stator that co-operate with the rotor armature. The compensation coil is connected in series with the main electromagnet coil, but carries current in the opposite direction to that carried by said main electromagnet coil. The device constitutes an axial abutment of optimized capacity without magnetic leakage.

The invention relates to a permanent-magnet and pulsed-eddy-current composite magnetic flux leakage detection method. With the method provided by the invention, defects on inner and outer surfaces can be effectively identified. The method belongs to the field of nondestructive test. With the effect of a permanent magnet, a ferromagnetic material requiring detection is magnetization into a local saturation state; if a detected magnetic flux leakage signal is larger than a preset intensity threshold B1, the ferromagnetic material has a defect; a reverse narrow pulse signal is applied to a excitation coil, such that the excitation coil generates a pulsed magnetic field, and pulsed eddy current is formed on the inner surface of the ferromagnetic material below two poles of a U-shaped magnetic yoke; at the time, if a detected leakage field intensity pulsation value is larger than a preset pulsation threshold B2, the defect is positioned on the inner surface of the ferromagnetic material; otherwise, the defect is positioned on the outer surface of the ferromagnetic material. The method provided by the invention has the advantages of simple hardware structure, low energy consumption, and convenient and fast signal processing.

According to the invention, a tandem alternator includes a rotary shaft, a first and a second field arranged in tandem on the rotary shaft, and a first and a second armature arranged in tandem in the axial direction of the rotary shaft. The first armature is provided on an outer periphery of the first field to constitute a first power generation unit. The second armature is provided on an outer periphery of the second field to constitute a second power generation unit. The first and second fields are arranged to abut each other in the axial direction of the rotary shaft, so as to minimize the axial length of the alternator. The first and second fields are configured to respectively create a first and a second magnetomotive force whose directions are opposite to each other, so as to minimize magnetic leakage between the first and second power generation units.

The invention discloses a single freedom degree magnetic levitation rotor support system, a magnetic levitation bearing and a magnetic biasing weight reducing device. The single freedom degree magnetic levitation rotor support system is composed of an attraction type axial magnetic levitation bearing (24), attraction type radial magnetic levitation bearings (25,26), magnetic biasing weight reducing devices (27,28) and air gap limit protective devices (29,30) of the axial and radial magnetic levitation bearings which are all arranged in the same movement mechanism. Active cell parts and stator parts of the axial and radial bearings are composed of a permanent magnetic field or a controllable magnetic device not generating non-work air gap magnetic leakage loss. So long as designing margin of the magnetic field is enough, the system of the invention can operate stably without adopting any form of sensor feedback control technology.

The system comprises: a driver, a magnetic leakage probe, a magnetic leakage signal processing device, a power device, a milometer on the rolling wheel of processing device, a rotary encoder and a positioning analysis module both fixed in the processing device; wherein, using gimbals to connect the first four devices in turn. This invention realizes precise positioning, and overcomes accumulated error.

This invention relates to deficiency identification and quantification based on three dimensional limit element neutral network, which comprises the following steps: a, according to deficiency leakage magnetic field three dimensional element computation module forming three dimensional element neutral network; b, measuring and extracting deficiency magnetic field characteristics value and setting measurement values and computing error valve conditions; c, given deficiency characteristics parameters initial values by use of three dimensional limit element neutral network for overlap computation to realize deficiency identification and evaluation through comparing deficiency computation values and error size.

The disclosed detection method for defect and magnetic leakage of a large-area steel plate comprises: local magnetizing the steel plate, detecting flux density on pole to calculate the inner magnetization saturation state by a formula; then, using multiple magnetic sensitive elements to form a detection probe to detect leakage flux density by equal interval, processing the output signal, comparing the detected value with dynamic-set threshold for decision. This invention improves cover range and space resolution, and ensures detection precision.

A clasp in which magnetic leakage is reduced includes a pair of pieces which are to be engaged with each other. Both pieces, when being engaged, both may rotate about an axis common to both pieces. Both pieces are provided with a pair of permanent magnets held in both pieces. Both permanent magnets have front and rear surfaces in which multiple poles are magnetized, and when both pieces are engaged, the front surfaces of both permanent magnets face each other.

The invention discloses an oil and gas pipeline intelligent internal detection device based on multi-module combined location. The device comprises an internal detector arranged inside an oil and gas pipeline and a floor marker arranged outside the oil and gas pipeline. The internal detector comprises a driving system, a magnetic leakage detecting system, a speed control system, a distance measuring system and a low frequency emitting system, wherein the driving system, the magnetic leakage detection system, the speed control system, the distance measuring system and the low frequency emitting system are relatively fixedly connected together; the floor marker at least comprises a low frequency receiving system; the low frequency emitting system is used for sending detection results obtained by the magnetic leakage detection system out of the oil and gas pipeline; the low frequency receiving system is used for receiving low frequency electromagnetic pulse signals transmitted by the low frequency emitting system. The oil and gas pipeline intelligent internal detection device based on the multi-module combined location can timely obtain the detection data of the pipeline detector and analyze the detection data and accordingly rapidly determine the defect conditions of the pipeline.

The invention relates to a mixed exciter synchronous machine, composed a PM (permanent magnet) synchronous machine and an electric excited synchronous machine, and placed in a case, where there is an exciting winding set on the rotor of the electric excited synchronous machine and a pair of electric brushes and a slide ring mounted on the rotating shaft, and the PM synchronous machine stator armature windings connects in series with those of the electric excited synchronous machine. Compared with the existing techniques, it has no axial / radial magnetic circuit and additional air gap, but low magnetic leakage and high electric exciting efficiency, convenient for structural design optimization and achieving the optimum energy-saving effect. The exciting current can be controlled, bidirectionally and meeting broad running speed requirements.

The invention relates to the technical field of pipeline defect detection and discloses a pipeline defect and magnetic leakage detection device which comprises a central shaft, a magnetic conduction device and a flux leakage detection device, wherein a left leather cup and a right leather cup are fixedly installed at both ends of the central shaft through a flange disc and a pressure plate, the magnetic conduction device which can conduct magnetism to a pipeline to be detected is installed on the central shaft between the left leather cup and the right leather cup, and a flux leakage detection device which can detect magnetic leakage signals is installed at the outer side of the middle part of the magnetic conduction device. The invention has the advantages of reasonable and compact structure and convenient use, and can efficiently magnetize an oil pipe and enhance the magnetization strength of a pipe wall to be detected, thereby greatly enhancing the detection quality of defects of an oil pipeline and being not easy to generate blockage when passing through a variable diameter part of the pipeline because of favorable deformation by arranging a plate spring.

The invention discloses a detection system of a pulsed magnetic flux leakage rail and a detection method thereof, and belongs to the rail non-destructive test field. The structure of the detection system comprises a sensor module, a signal conditioning module, a data acquisition module, a signal stimulating module, a computer processing module and a coded disc position acquisition module; a U-shaped magnetic yoke coil exerts magnetic field excitation on a tested rail, magnetic force line distribution is generated between the tested rail and a coil magnetic yoke, the surface of the rail cracks, the distribution of the magnetic force line changes due to the existence of cracks near the cracks on the surface of the rail, and generates magnetic flux leakage; and square-wave signals with adjustable frequency are exerted on an exciting coil by the impulse excitation technology so that the magnetic flux leakage situation is applicable to the cracks with different depths. The system and the method perform non-contact type non-destructive test on the rail surface and shallow surface cracks, the device has a simple structure and the system has high reliability.

The invention discloses a multifunctional electromagnetic stirrer, comprising six layers of annular cores (1) which are horizontally arranged, six rack cores (2) which are vertically arranged and thirty-six identical solenoid coil windings (5); the six layers of annular cores are mutually independent layer by layer, are aligned vertically and are separated at intervals; the inner wall of each layer of annular core is provided with six salient poles (3); the six rack cores are uniformly distributed on the outer walls of the annular cores; each rack core is provided with five salient poles (4); the salient poles of the rack cores are inserted into the intervals, which are vertically separated, of the annular poles; the salient poles of each rack core and the salient poles of the six layers of annular cores are located on the same circumference; the top surfaces of the salient poles of each rack core are inserted into the inner walls between the salient poles of the annular cores; the thirty-six solenoid coil windings are respectively sleeved on each salient pole of the annular cores; and three-phase low-frequency alternating current is supplied by a variable-frequency power source. According to the multifunctional electromagnetic stirrer, the structure is simple, the size is small, magnetic leakage is small, and the working efficiency is high.

The invention is a quantizing method for detecting corrosive defect by using magnetic leakage. The invention uses the distribution property of the detected leakage magnetic field to implement quantizing corrosive defect size according to a specified algorithm. The concretely implementing method: firstly making a sample with three series of standard defects, according to the leakage magnetic detected data, determining the length, width and coefficient in deep quantizing method, thus obtaining a corrosive defect quantizing method and providing a basis for evaluating using state of equipment and equipment maintenance. The invention effectively overcomes the disadvantage of being difficult to quantize corrosive defect and defect depth in existing techniques, and the method of the invention is simple and easy to apply and able to be implemented, manually and by computer, high-efficiency and having a wider application prospect.

The invention discloses a dual-Hall element current sensor and belongs to a current sensing device. The dual-Hall element current sensor is capable of solving the problems that the magnetic leakage is high and the measurement accuracy is lower due to the fact that air gaps in an iron core of a traditional dual-Hall element current sensor are bigger, and meanwhile, reducing outside noise interference, magnetic field interference, electrostatic interference and the like, and is used for measuring alternating current or direct current. The dual-Hall element current sensor disclosed by the invention comprises an insulating shell, an open annular iron core and two Hall elements, wherein the open annular iron core is located in the annular cavity of the insulating shell; the two Hall elements are located in the same air gap of the open annular iron core and the same section which is vertical to a magnetic line of force; the insulating shell is provided with a wiring terminal; the two Hall elements are respectively and electrically connected with the wiring terminal; and a magnetic shielding ring is arranged between the insulating shell and the open annular iron core. According to the dual-Hall element current sensor disclosed by the invention, by the placement mode of the two Hall elements, the magnetic leakage of the open iron core is reduced, and the measurement accuracy is correspondingly improved. The interference of a peripheral electromagnetic field can be effectively shielded by the arranged magnetic shielding ring.

A permanent magnet rotor for a motor, the permanent magnet rotor including an iron core and a permanent magnet. The iron core includes an annular ring having a central axial bore and a plurality of magnetic induction blocks protruding outwards from an outer side of the annular ring. Between two adjacent magnetic induction blocks form a radial recess for mounting the permanent magnets. The magnetic induction blocks at both sides of an opening of the radial recess protrude with a hook block. The section of an outer side surface of the magnetic induction blocks is a circular-arc line and the outer side surface employs a point with a distance deviating from the center of the central axial bore as a center of circle. The permanent magnet rotor has a simple structure, low magnetic leakage and torque ripple, big counter-electromotive force constant, and smooth waveform of counter-electromotive force.

The invention provides a nondestructive flaw detector for steel wire ropes, and solves the problem that quantitative detection of wire break and wear in steel wire ropes cannot be realized by the prior art. The nondestructive flaw detector for steel wire ropes comprises a steel wire rope walking positioning mechanism, a magnetic leakage flux detector, an optical detector, a photoelectric encoder, and an embedded signal processing system. The steel wire rope walking positioning mechanism is provided with a steel wire rope channel, the inner wall surface of which is fixed with the magnetic leakage flux detector, the optical detector and the photoelectric encoder. The embedded signal processing system is fixed on the steel wire rope walking positioning mechanism, and the magnetic leakage flux detector, the optical detector and the photoelectric encoder are connected to the embedded signal processing system. By combining a magnetic leakage flux technology and an optical determination technology to perform signal feature extraction and quantitative analysis on wire break, pitting corrosion, wear and other defects of steel wire ropes, the nondestructive flaw detector realizes online high speed and high accuracy detection of the steel wire ropes.

The present invention relates to the invention of the magnetic flux leakage flaw detection method. The strong magnets such as steel plates are magnetized in multiple magnetic fields of different strengths, and the magnetic probes are used to detect the magnetic flux leakage of the magnetized strong magnets, or the strong magnets are magnetized in a certain magnetic field. A plurality of magnetic probes arranged at different positions along the magnetization direction are used to detect the magnetic flux leakage of the magnetized strong magnet, and the output signal of the magnetic probe after the detected magnetic flux leakage is subjected to the calculation of highlighting the signal generated by the internal defect of the strong magnet. In addition, the magnetic flux leakage flaw detection method can be used to detect defects with high precision, so the hot-rolled steel sheet after hot rolling is inspected by this method, and the detected defect is calibrated on the position of the defective steel sheet, so that the correct defect can be grasped in advance. Scaled or descaled hot-rolled steel sheet with location information.