3812 results about "Excitation coil" patented technology

A wireless power system capable of transmitting power through the skin without percutaneous wires over distances ranging from a few inches to several feet includes an external transmitting coil assembly and a receiving coil assembly. The transmitting coil assembly includes an excitation coil and transmitting resonant coil which are inductively coupled to each other. The receiving coil assembly includes a receiving resonant coil and a power pick-up coil which are also inductively coupled to each other. A high frequency AC power input, such as radio frequency (RF), supplied to the excitation coil inductively causes the transmitting resonant coil to resonate resulting in a local time varying magnetic field. The transmitting and receiving resonant coils are constructed as to have closely matched or identical resonant frequencies so that the magnetic field produced by the transmitting resonant coil is able to cause the receiving resonant coil to resonate strongly also, even when the distance between the two resonant coils greatly exceeds the largest dimension of either coil. The receiving resonant coil then creates its own local time varying magnetic field which inductively produces a voltage in a power pick-up coil to provide power to an active implantable medical device or implantable rechargeable battery.

A fixer includes a fixing member provided with a rotary heat generator, a pressure member to form a nip with the fixing member to sandwich the sheet, an excitation coil disposed facing a heat generation layer of the rotary heat generator to generate magnetic flux that inductively heats the heat generation layer, a loop-shaped demagnetization coil unit disposed facing the heat generation layer to generate magnetic flux that partly counteracts the magnetic flux generated by the excitation coil, a first magnetic core disposed in a first area that is enclosed by both the excitation coil and the demagnetization coil unit, and a second magnetic core disposed in a second area that is outside a loop of the demagnetization coil unit and enclosed by the excitation coil. The first magnetic core and the second magnetic core are magnetically continuous in a rotary axial direction of the rotary heat generator.

An image forming apparatus includes an image carrier, a developing unit, a transfer unit, and a fixer to fix an image formed on a sheet and includes a rotary heat generator including a heat generation layer, a pressure member to form a nip with the rotary heat generator to sandwich the sheet therebetween, an excitation coil disposed facing the rotary heat generator, to inductively heat the heat generation layer, a demagnetization coil disposed facing the heat generation layer, to generate magnetic flux that partly counteracts magnetic flux generated by the excitation coil and a fixer controller to control activation of the excitation coil as well as the demagnetization coil before a second image formation job after completion of a first image formation job in which an image is formed on a sheet of recording media whose width is smaller than a maximum sheet width usable in the fixer.

A position detecting device is provided. The position detecting device includes a position pointer which transmits a position-pointing signal using a power supply stored in a rechargeable power storage unit, and a tablet which detects a position pointed to by the position pointer when receiving the position-pointing signal. The position pointer includes a coil, a charging circuit for charging the power storage unit, and a transmitter for transmitting the position-pointing signal. The tablet includes an excitation coil wound around a periphery of a position detecting area of the tablet, an excitation circuit for supplying an alternating voltage to the excitation coil, a position-pointing signal detector for detecting the position-pointing signal received from the position pointer, and an excitation controller for controlling a supply of the alternating voltage to the excitation coil based on the detected position-pointing signal.

A fixing device includes an excitation coil, a heat-generating layer, a magnetic shunt layer, and a degaussing member. The excitation coil generates a magnetic flux. The heat-generating layer generates heat using the magnetic flux generated by the excitation coil. The magnetic shunt layer transmits heat generated by the heat-generating layer. The degaussing member sandwiches the magnetic shunt layer together with the excitation coil, and selectively performs degaussing by generating a repelling magnetic flux for canceling the magnetic flux generated by the excitation coil so as to activate a self-temperature-control function. The degaussing member selectively refrains from degaussing so as to deactivate the self-temperature-control function.

The fixing device using an electromagnetic induction heating (IH) method includes a fixing sleeve having a heating layer, a pressure roller to form a nip while contacting the fixing roller and rotate to drive the fixing sleeve, a temperature detector to detect a temperature on a circumference of the fixing sleeve, and an excitation coil provided near the fixing sleeve and configured to perform induction heating of the heating layer of the fixing sleeve based on the detection result from the temperature detector. The fixing device is configured to change a rotation speed of the fixing sleeve in a standby time during which the fixing sleeve, while rotating, is controlled to be heated so as to maintain a target temperature when a periodic temperature difference occurs on a circumference of the fixing rotary member and having a fluctuation amplitude larger than a predetermined value compared to the target temperature.

An excitation coil (19) surrounding the periphery of the position detecting area is connected to an oscillating circuit (21), which oscillates at a frequency f0, through a drive circuit (20). A CPU (18) supplies control signals to a selecting circuit (12), a sample-and-hold circuit (16), an A / D conversion circuit (17), and the drive circuit (20). Based on the control signal output from the CPU (18), the drive circuit (20) controls the power of the signal output from the excitation coil (19) to ON or OFF. Further, the strength of the excitation signal supplied from the excitation coil (19) is controlled based on information obtained by analyzing a signal received from a position indicator (40), such as the position indicated by the position indicator on the position detecting area and / or a strength of the signal received from the position indicator.

The present invention is directed to configurations of eddy current probes and methods for using these probes to detect cracks initiating at the edge of holes in single-layered or multi-layered metallic structures. The new devices and methods are suitable to detect buried cracks around fastener holes located in layers of multi-layered structures, for example in airplane wing splices, containing fasteners disposed in rows. The probes include excitations coils and one or more magnetic sensors. The magnetic sensors can be arranged in absolute, differential or array configurations. The probe is scanned linearly along the fastener row. The invention also contains an apparatus or system for monitoring cracks around holes, including signal processing circuits, driving circuits, data acquisition and display, and scanning systems.

A method and device for monitoring vascular access is described. A field coil is placed at a location on an extracorporeal circulation loop connected to the vascular system of a patient, and an induction coil is placed at another different location. A voltage is supplied to the field coil, inducing an electric current in the blood. The current induces a voltage in the induction coil. Monitoring the voltage in the induction coil reveals if vascular access is defective.

A magnetic field sensor for the measurement of at least one component of a magnetic field comprises a ferromagnetic core that serves as a magnetic field concentrator, an excitation coil and a read-out sensor. The read-out sensor preferably comprises two sensors arranged in the vicinity of the outer edge of the ferromagnetic core and measures the at least one component of the magnetic field. The ferromagnetic core is ring-shaped or disc-shaped. On operation of the magnetic field sensor, a current is temporarily applied to the excitation coil in order to bring the ferromagnetic core into a state of predetermined magnetization in which the magnetization of the ferromagnetic core produces no signal in the read-out sensor.

A force feedback interface device that provides force feedback to a joystick handle manipulated by a user. A force feedback device inputs control signals to a computer and outputs forces to a user of the force feedback device. The device includes a housing gripped by the user of the force feedback device and a joystick handle manipulable in at least two rotary degrees of freedom by the user, such as a gamepad. Sensors detect a position of the joystick handle and two direct drive actuators each provide torque in a rotary degree of freedom. Each of the actuators is a brushless, single phase actuator having a grounded excitation coil and a moving magnetic material. The joystick is mechanically constrained to not move past either of two limits where the torque output by the actuator in an unenergized state changes direction. The joystick handle can be oriented such that a center position is substantially at a local minimum reluctance position of the actuator, where the joystick is mechanically constrained to not move substantially past either local maximum reluctance position adjacent to the local minimum reluctance position. The local minimum reluctance position can in some embodiments provide a centering spring force on the joystick handle.

A fixing device includes an excitation coil, a heat-generating layer, a magnetic shunt layer, and a degaussing member. The excitation coil generates a magnetic flux. The heat-generating layer generates heat using the magnetic flux generated by the excitation coil. The magnetic shunt layer transmits heat generated by the heat-generating layer. The degaussing member sandwiches the magnetic shunt layer together with the excitation coil, and selectively performs degaussing by generating a repelling magnetic flux for canceling the magnetic flux generated by the excitation coil so as to activate a self-temperature-control function. The degaussing member selectively refrains from degaussing so as to deactivate the self-temperature-control function.

The present invention relates to a method and to a device for adapting the alternating current generated by a generator (1) and the alternating voltage generated by a generator (1) to a grid (8), whereby the generator (1) has at least one excitation coil (2). The power fed into the grid (8) can be flexibly adapted while entailing low switching losses in that a static frequency converter (9) is employed for the adaptation between the generator (1) and the grid (8), and in that, in order to control the power fed into the grid (8), means (3) are provided with which, on the one hand, the strength of the excitation field generated by the at least one excitation coil (2) is regulated and, on the other hand, the phase angle between the frequency converter voltage and the generator or grid voltage is appropriately controlled.

The invention presents a self-supplied magnetic current damper, which includes a magnetic current damper, a vibration energy collector, and an energy storage management module. The energy collector is a multi-vane disc shaped electro-magnetism type mechanical energy collector installed on the piston bottom of the magnetic current damper, which is composed of multiple impellers and disc shaped magnetoelectric transducers, wherein, the disc shaped magnetoelectric transducers are mounted on the piston, the multiple impellers are mounted on the rotor of the disc shaped magnetoelectric transducers, and the energy produeced by the disc shaped magnetoelectric transducers is lead out by the coil on the stator. The output lines of the disc shaped magnetoelectric transducers are connected to the energy storage management module, and the output of the energy storage management module is connected to the magnetizing coil of the magnetic current damper. During work, the magnetic current liquid impacts the vanes, the impeller converts the fluid washing into the rotation of the disc shaped stator inlaid on the rare-earth permanent magnet, the magnetic flux of the coil on the disc shaped stator is changed, in order to achieve effective collection of mechanical energy, and greatly reduce the transducer volume.

A kind of inversion magnetic current alter amortisseur,which has application in the absorption of vibration of the building structure and the locomotive cars. It includes the cylinder body,the piston, the piston rod which connected to it, the confinement gasoline device of the both sides of the cylinder body and the cylinder cap, there has magnetic current alternative liquid in the void of the cylinder body, and institutes the magnetizer that generates the magnetic field and the energizing coil and the electromagnet magnetic circuit component which is unitized of the running void, the cylinder body is composed of the master cylinder, or the master cylinder and the set jar, or the master cylinder and bypass jar, its character is:Institutes both the energizing coil and the permanent magnet magnetic circuit, composes the compounded magnetic circuit with the energizing coil and the permanent magnetic field, and also institutes the administer void in the electromagnet circuit, and when the power is cut, the most of the permanent magnetic field that generated by the permanent magnet will pass through the running void, so the amortisseur can work at the great amortization condition. The component of the electromagnet circuit may set at the pertinent position in terms of the different cylinder body. This kind of amortisseur can joint with the controlled structure, fulfills the semiactivly controlled with the absorption of vibration.

An antenna includes excitation terminals responsive to an RF source to supply an RF electromagnetic field to a plasma that processes a workpiece in a vacuum chamber. A matching network includes first and second portions respectively between the source and terminals and between the terminals and the antenna plasma excitation coil. In response to indications of impedance matching between the source and its load, currents flowing between (1) the first portion and the terminals and (2) the terminals and the coil are controlled so the latter exceeds the former. The indications control impedances of the first and second portions or the first portion impedance and the source frequency. The coil can include a transformer having a primary winding coupled to the excitation terminals and a multi-turn plasma excitation secondary winding.

The invention discloses an online oil way abrasive particle monitoring device. An amplitude difference and a phase difference of excitation signals on two groups of excitation coils of an oil way abrasive particle sensor are adjusted during initially electrifying, so that the polarities of magnetic fields generated by the two excitation coils of the oil way abrasive particle sensor are reversed and neutralized in a middle detection coil. Consequently, when oil liquid without abrasive particles passes through the oil way abrasive particle sensor under ordinary circumstance, only a small carrier signal is output from the detection coil; when oil liquid with abrasive particles passes through the sensor, generated abrasive particle signals are modulated on the carrier signal and subsequently transmitted into a signal detecting circuit to amplify and demodulate, so that effective abrasive particle signals can be acquired; the abrasive particle signals are transmitted to a DSP (Digital Signal Processor) to process so as to acquire parameters, such as the size, the number and the material, of the abrasive particles; and due to the parameters, the abrasion condition of a monitored mechanical device is reflected, so that the health condition of the monitored device is acquired in real time and the online monitoring on the oil way abrasive particles is realized.

A system for generating a magnetic field for excitation of a leadless marker assembly. The system of at least one embodiment includes a source generator that generates a plurality of alternating electrical signals each having an independently adjustable phase. A plurality of excitation coils are configured to simultaneously receive a respective one of the alternating electrical signals at a selected phase to generate a magnetic field. The phase of the alternating electrical signal for each excitation coil is independently adjustable relative to the phase of the alternating electrical signal for the other excitation coils so as to adjust the magnetic field from the respective coil. The magnetic fields from the excitation coils combine to form a spatially adjustable excitation field for excitation of the remote leadless marker assembly.

In a magnet-exciting rotating electric machine system, a rotor surface has magnetic salient poles and island-shaped magnetic poles alternately in circumferential direction, and the island-shaped magnetic poles are constituted so that magnetic flux coming from an external source does not flow through. A magnetic excitation part magnetizes the island-shaped magnetic poles and the magnetic salient poles collectively in the same direction, and then control a flux amount flowing through an armature. The armature has armature coils that face the magnetic salient pole and the island-shaped magnetic pole simultaneously so that driving torque fluctuation or power generation voltage waveform distortion is controlled. The magnetic excitation part changes magnetization state of a field magnet irreversibly, or changes an excitation current to an excitation coil to control a flux crossing the armature.

The invention discloses a composite excitation partitioned stator and rotor switched reluctance motor belonging to the field of switched reluctance motors. The motor can be in a three-phase 6 / 4, four-phase 8 / 6 or three-phase 12 / 8 structure and the like and comprises U-shaped stator blocks, excitation coils, magnet vanes, permanent magnets, segmental rotor tooth blocks and a non-magnetic conduction rotor metallic sheath, wherein the segmental rotor tooth blocks are embedded into the non-magnetic conduction rotor metallic sheath; one magnet vane is arranged between two adjacent U-shaped stator blocks; the permanent magnets are embedded between two stator tooth notches of each U-shaped stator block; the excitation coils are wound on the yokes of the U-shaped stator blocks; and the excitation field generated by each excitation coil wound on the yoke of each U-shaped stator block is in parallel connection with the permanent magnetic field generated by the permanent magnet embedded between two stator tooth notches of the U-shaped stator block. The motor of the invention has high torque, small wind resistance loss when the rotor operates at high speed, small end winding, strong fault tolerance and low production cost.

The invention discloses a DSP-based electromagnetic flowmeter signal processing system, which comprises a hardware system and a software system. The hardware system consists of an excitation driving module, a signal modulation and acquisition module, a signal processing control module, a man-machine interface module, a communication module and a power supply management module. The signal control module uses DSP as a core. In the system, a high frequency square wave excitation control scheme is adopted, and the DSP generates an excitation time sequence to control the excitation driving module to perform high frequency square wave excitation of a magnet exciting coil; the signal modulation and acquisition module amplifies and filters an output signal of an electromagnetic flowmeter, performs the analog-to-digital conversion of the output signal and outputs the output signal to the DSP; the software system processes an acquired signal to obtain a flowmeter measurement result and send the result to a liquid crystal display; and the parameters of the flowmeter are set by keyboard operation or by the interaction between a master computer and the flowmeter by the communication module. The system can realize the high-accuracy and high-speed measurement of fluid flow, particularly the measurement of flow of liquid-solid two-phase fluid such as pulp.

A metal detector has a circular excitation coil (10) through which foodstuffs to be tested (65) pass, on a conveyor belt (40). The excitation coil (10) is excited by a stable oscillator (50) and the lines of flux generated by the excitation coil (10) link two receiver coils (20, 30) equidistantly spaced either side of the excitation coil (10). As a foodstuff (65) having a foreign ferromagnetic or electrically conductive object therein passes through the receiver coils (20, 30), a voltage is induced in them. This induced voltage is phase compensated. The change in amplitude or frequency of the oscillator (50) as the foodstuff (65) moves through the excitation coil (10) is also passed to the processor (70) which removes the artifacts from the detector signal caused by the volume of the foodstuff (65) itself. The resultant signal, which was previously swamped by the effect of the volume of the foodstuff itself, can then be detected and the foodstuff can be removed from the conveyor (40).

The present invention is horizontal continuous light alloy casting process and apparatus with cooperation of power ultrasonic wave and low frequency electromagnetic wave. In the continuous casting apparatus, one set of exciting windings is set inside the water jacket and applied with AC power to produce low frequency electromagnetic field, or one set of exciting windings is set inside the water jacket while one other set of exciting windings is set between the crystallizer and the pouring basket to produce electromagnetic fields. At the same time, one ultrasonic rod is inserted into the crystallizer to apply power ultrasonic field during casting. The present invention can reduce the temperature gradient in casting blank solidification, alter liquid hole shape, raise the homogeneity of the casting blank and raise casting blank quality.

The solenoid is capable of generating great thrust and having broad-ranging thrust characteristics. The solenoid of the present invention comprises: a guide pipe formed into a cylindrical shape and provided inside of an excitation coil; a movable element having a small diameter section and a large diameter section; a first yoke part covering one end face of the excitation coil, the first yoke part having a first facing surface, which faces an outer circumferential face of the small diameter section of the movable element, and a second facing surface, which faces one end face of the small diameter section; and a second yoke part covering the other end face of the excitation coil, the second yoke part having a third facing surface, which faces an outer circumferential face of the large diameter section of the movable element, and a fourth facing surface, which faces one end face of the large diameter section.

The present invention provides an object sensor configured such that excitation coils (13c and 13d) and a detection coil (12) are separately disposed, and the detection is performed in accordance with the balance between the excitation coils (13c and 13d) in a pair, a residual variation amount after the impedance due to a DC resistance part and the like has been offset and removed is obtained at high sensitivity with excellent linearity while using a small core body (11), regardless of the impedance including a DC resistance part. Additionally, the object sensor to be used as an inlet sensor is located in an appropriate position on a more upstream side than the read / write position in an insertion direction of the IC card. A contact terminal portion of the IC card is sensed whereby to detect the validity of the card inserted into the apparatus from a card insertion slot. Thereby, steady detection operations can be implemented for the presence or absence of the IC card, notwithstanding environmental temperature variations.The invention further provides an IC card reader configured such that a plurality of inlet sensors for detecting the type of an inserted card is provided in appropriate positions more upstream than the read / write position in a card insertion direction, wherein when an unusable card or the like is inserted, a control operation of closing shutter means can be performed, thereby enabling illegal action with the card to be prevented.

This electromagnetic switching device comprises an electromagnetic device 1 in which a movable core 15 comes into contact with or separates from a fixed core 14 in response to energization of an excitation coil 11 wound around a coil bobbin 10 a contact device 2 with a fixed contact 21 and a movable contact which comes into contact with or separates from the fixed contact in conjunction with a movement of the movable core 15 of the electromagnetic device, and a boxy case 3 configured to house the electromagnetic device and the contact device. The coil bobbin 10 has a flange 10a at its end in an axis direction of the coil bobbin, and the case 3 has, on its inner surface, a recess 31 into which a periphery of the flange 10a of the coil bobbin is fitted, and a cushioning member 32 for absorbing an impact which is transmitted from the electromagnetic device to the case is disposed in the recess, and the flange of the coil bobbin is supported by the recess through the cushioning member whereby the electromagnetic device is supported in the case.

An oil metal abrasive particles online monitoring system comprises sensors, a microprocessor and a circuit; each sensor is a solenoid type inductive transducer, and an oil circuit can pass through the solenoid of the inductive transducer; an excitation AC signal-generator is connected with two excitation coils respectively in two totally same sensors, and two induction coils of the two sensors are connected with a signal amplifier; and the signal amplifier, a RMS-DC converter, an AD converter, the microprocessor and a display are in a sequential connection, and the microprocessor is also connected with a keyboard and an alarm. The monitoring system is reasonable in structure, high in sensitivity of monitoring weak signals outputted by the inductive transducer, good in linearity, good in anti-interference capability, stable and reliable in operation, convenient to operate, good in real-time performance, high in measuring precision, and accurate and reliable in monitoring result. The monitoring system can be used in military and civil fields, be used to monitor and diagnose oil pollutant degree and faults of machinery equipment such as various airplanes, ships, automobiles and the like, and the occurrence of various engine accidents is avoided.

A system for sensing stress in a ferromagnetic material is provided. The system includes at least one magnetic flux device configured to induce a conditioning magnetic flux in the ferromagnetic material. The system also includes a sensor positioned proximate to the ferromagnetic material. The sensor includes a core, at least one excitation coil configured to induce a second magnetic flux in the ferromagnetic material, and at least one detector configured to detect changes in the second magnetic flux.