60 results about "Magnetic path length" patented technology

The challenge to be solved by the present invention is the miniaturization of a 1-300 W class of motor. This can be achieved by using a hollow-cylinder shaped anisotropic bonded magnet magnetized in a 4-pole configuration. The anisotropic bonded magnet has a maximum energy product approximately 4 times greater than the conventional sintered ferrite magnets. The use of a 4-pole configuration shortens the magnetic path length of the individual magnetic circuits and the magnetic force contributing to the torque is increased. When the torque is kept the same as in the conventional motor, the length of the electromagnetic rotor core and the axial magnet length can be reduced. In this fashion, 1-300 W class motors can be reduced in size.

The invention relates to an Epstein frame-based electrical sheet specific total loss measurement method, which belongs to the technical field of electromagnetic measurement. The technical scheme is as follows: three sizes of Epstein frame models are adopted to carry out the total loss measurement of the same group of measured electrical sheet samples; according to a secondary weighted average method, the effective magnetic path lengths of two groups of Epstein frames are calculated, and finally, different magnetic path lengths corresponding to different magnetic flux densities are obtained; and meanwhile, the secondary weighted average method is utilized to calculate specific total loss. The method has the advantages that: except for the measured electrical sheet samples, the material of other components is nonferromagnetic material, and therefore the affection of ferromagnetic material except for the test pieces on the measurement result is eliminated; and the method can be used for measuring the specific total loss of various brands of electrical sheets and analyzing the effective magnetic path lengths of Epstein frames and the loss of transformers and motors.

A wire-wound type chip coil can take various inductance values while maintaining its outer dimension at a specific fixed value. A chip coil is formed by winding at least two conductive wires regularly in a single layer around a core made of a magnetic material and firmly connecting both ends of each conductive wire to terminal electrodes disposed on respective flanges of the core. This makes it possible to obtain a great current capacity. Furthermore, the inductance decreases because of an increase in the magnetic path length. A great number of different inductance values can be easily obtained by properly selecting parameters including the number of substantially parallel conductive wires, the diameter of each conductive wire, and the number of turns.

A film thickness of second coil layers (second coil pieces) disposed below a main magnetic pole layer (first magnetic layer) is larger than a film thickness of first coil layers (first coil pieces). Hence, while a magnetic path length of magnetic flux flowing through the main magnetic pole layer (first magnetic layer) and a return path layer (second magnetic layer) is decreased by decreasing the film thickness of the first coil layers (first coil pieces) disposed in a space between the main magnetic pole layer (first magnetic layer) and the return path layer (second magnetic layer), series resistance of an entire coil layer can be decreased by increasing the film thickness of the second coil layers (second coil pieces).

A magnetostrictive vibration power generation device including: a longitudinal magnetostrictive element formed of a magnetostrictive material and configured to be attached to a vibrating member at at least one end part thereof; a coil wound on a closed magnetic path constituted including the magnetostrictive element; and a permanent magnet arranged so as to apply a bias magnetic field to the closed magnetic path. A yoke member formed of a magnetic material is arranged in parallel at a side of the magnetostrictive element, and the closed magnetic path is formed including the magnetostrictive element and the yoke member, the permanent magnet is attached to the yoke member on the closed magnetic path, and the yoke member is allowed relative displacement in relation to the magnetostrictive element on at least one side in a magnetic path lengthwise direction of the closed magnetic path.

A magnetic head includes first and second magnetic layers and first and second coil pieces in a space between and outside the first and second magnetic layers, respectively. A film thickness of second coil layers (second coil pieces) disposed below a main magnetic pole layer (first magnetic layer) is larger than a film thickness of first coil layers (first coil pieces). Hence, while a magnetic path length of magnetic flux flowing through the main magnetic pole layer (first magnetic layer) and a return path layer (second magnetic layer) is decreased by decreasing the film thickness of the first coil layers (first coil pieces) disposed in a space between the main magnetic pole layer (first magnetic layer) and the return path layer (second magnetic layer), series resistance of an entire coil layer can be decreased by increasing the film thickness of the second coil layers (second coil pieces).

A wire-wound type chip coil can take various inductance values while maintaining its outer dimension at a specified fixed value. A chip coil is formed by winding at least two conductive wires regularly in a single layer around a core made of a magnetic material and firmly connecting both ends of each conductive wire to terminal electrodes disposed on respective flanges of the core. This makes it possible to obtain a great current capacity. Furthermore, the inductance decreases because of an increase in the magnetic path length. A great number of different inductance values can be easily obtained by properly selecting parameters including the number of substantially parallel conductive wires, the diameter of each conductive wire, and the number of turns.

The invention discloses a three-phase electromagnetic balancing energy-saving electric reactor. The three-phase electromagnetic balancing energy-saving electric reactor mainly consists of coils (1), core limbs (2), an upper iron yoke (3), a lower iron yoke (6) and a tightening bolt (4), wherein the coils (1) are arranged on the core limbs (2) in a sleeving mode, clamped between the upper iron yoke (3) and the lower iron yoke (6), and fixed by tightening the upper iron yoke (3) and the lower iron yoke (6) through a tightening bolt (4). During usage, the three-phase electromagnetic balancing energy-saving electric reactor is in series connected in a to-be-governed power grid of an electric power system without special operation needs and quick-wear parts, so that the application is convenient and the operation maintenance cost is low. The three-phase electromagnetic balancing energy-saving electric reactor can be manufactured into a dry-type structure and also can be manufactured into an oil-immersion structure, is simple in structure, high in practical performance, easy for large-scale production, convenient to dismount, and easy to maintain; an arrangement structure of the core limbs is in the shape of an equilateral triangle, three magnetic paths are consistent in length, shortest, and are equal in three-phase magnetic resistance; a three-phase coil is arranged on each magnetic pillar, and therefore, the magnetic resistance is relatively balanced and the loss is low. The three-phase electromagnetic balancing energy-saving electric reactor can be widely applied to balancing a three-phase power supply phase angle in electric systems of factories, authorities, residential areas and the like, increasing a system utilization rate, and lowering harms of impact and waveform distortion of large-power equipment operation to the power grid, so that purposes of saving energy and operating safely are achieved.

The invention discloses a vibration power generation device comprises a power generation part and a support part, wherein the power generation part comprises a top cover, an upper permanent magnet, a magnetostrictor and a lower permanent magnet which are sequentially laminated and fixed, a coil is wound around the magnetostrictor, and the support part comprises an elastic part and a base. During usage, pressure is applied to the top cover, so that the upper permanent magnet, the magnetostrictor, the coil and the lower permanent magnet downwards move together to cause change of the length of a magnetic path, the coil generates a changing magnetic field, and an induced electromotive force is generated in the coil according to a Faraday law of electromagnetic induction, namely electromagnetic power generation; and when the top cover is pressed, the base is extruded by the lower permanent magnet and is knocked, so that the magnetic path is closed, meanwhile, a generated counter-reacting force acts on the magnetostrictor, the changing magnetic field is generated in the coil according to an inverse magnetostriction effect, and the induced electromotive force is further generated, namely piezomagnetic power generation. The device is simple to design and comprises two power generation processes of electromagnetic power generation and piezomagnetic power generation, and the power generation efficiency is improved.

The invention provides an induction power taking device of a non-closed type magnetic core, which comprises a non-closed type drawable magnetic core coil assembly and an electric energy management module connected with the drawable magnetic core coil assembly, and is characterized in that the drawable magnetic core coil assembly comprises a plurality of thin column type magnetic cores and a magnetic core coil arranged on the outer sides of all the thin column type magnetic cores in a sleeving manner; at least a portion of the fine cylindrical core is drawable with respect to the core coil. The non-closed type magnetic core is adopted in the induction power taking device of the non-closed type magnetic core, the problem that different voltage classes of the induction power taking device are matched and compatible with the cable diameter is solved, meanwhile, a traditional whole magnetic core is equivalently replaced by several thin magnetic cores with higher effective magnetic conductivity, the magnetic cores can be drawn to change the length of a magnetic circuit in the magnetic cores, and therefore the magnetic core can be replaced by the thin magnetic cores with higher effective magnetic conductivity. And the output power and the power density of the whole magnetic core can be improved.

The invention relates to a wide-frequency square-wave transformer for measurement and protection and a manufacturing method thereof. The square-wave transformer is used for measuring and protecting electrical parts and equipment and belongs to the technical field of electrical measurement and protection, comprising an iron core and a winding, wherein the iron core is of an R type iron core processed through vacuum high-temperature annealing, cooling and non-oxidation treatment; the size of the iron core is 2700-3000 square millimeters in area; the length of the magnetic path is 600-630 millimeters; and the winding comprises a first winding and a second winding. The transformer has the advantages of large variation range of working frequency value, square wave of voltage waveform, high requirement on precision, little distortion of waveform restoration, high grade of voltage withstand, high mechanical strength and good protective performance.

A device for measuring electrical current in a line may include, among other things, a Hall effect sensor wherein a first response is generated by electrical current in the line; a current transformer disposed with the line extending axially therethrough and connected in series to the Hall effect sensor wherein a second response is generated by the electrical current in the line. An equalizer may be connected to the Hall effect sensor and to the current transformer and may be configured to flatten the first and second responses relative to each other. The permeability magnetic path length and cross section of the current transformer is selected such that low frequency roll-off of the current transformer is at a lower frequency than high frequency roll-off of the Hall effect sensor.

The invention belongs to the field of electromechanical switched reluctance motors and relates to a rotor slotless switched reluctance motor, in particular to a switched reluctance motor having a rotor slotless structure. A stator of the rotor slotless switched reluctance motor has a magnetic pole structure which is formed by combining six main magnetic poles and auxiliary magnetic poles; a rotorhas an anisotropic axial lamination structure and is laminated into a four-pole structure; the axial lamination structure comprises a rotary shaft, a non-magnetic-conduction bracket, an axial lamination, a non-magnetic-conduction filling material and a non-magnetic-conduction fastening ring; and magnetic poles of the axial lamination are formed by alternately laminating a high-magnetic-conductionmaterial silicon steel sheet and a non-magnetic-conduction insulating material lamination along the axial direction. The rotor slotless switched reluctance motor has the advantages that: by adopting combined stator magnetic poles and an axial laminated rotor, the length of a magnetic path is reduced, the iron loss of the switched reluctance motor can be reduced, and the torque pulsation of the switched reluctance motor is effectively reduced; and windings are wound on the main magnetic poles, so that the windings are convenient to embed, the problem about insulation is solved, and the utilization rate of a slot is high.

The present invention provides a magnetic head, which performs highly efficient recording / reproducing even when a magnetic path length is shortened, and a signal wavelength is short. This magnetic head is provided with magnetic body parts and made of a pair of soft magnetic materials, in which main surfaces face a recording medium, and a magnetic gap, in which a gap between the pair of magnetic body parts in a side opposite the main surface is wider than that in the main surface, and continuously changed from the main surface side to the side opposite the main surface.

The invention provides a small type current clamp for the checking of a live line measurement scene, wherein one end of a current clamp body is arranged in a clamp body jacket; the other end of the current clamp body stretches out of the clamp body jacket; a clamp body embedment is arranged at an out-stretching current clamp head; a clamp body sliding chute in the same direction with a clamp body is formed in the middle part of an out-stretching end of the current clamp body; the interior of the current clamp head is provided with a measurement magnetic core component which can move left and right along the clamp body sliding chute; and a dynamic magnetic arm and a static magnetic arm of the component are closed to form a closed magnetic circuit and are opened to cause the whole closed magnetic circuit to be disconnected. With the adoption of the small type current clamp for the checking of the live line measurement scene, the problem that due to large volume, the current clamp of the prior art is inapplicable for small operation space is solved; moreover, the working position of the measurement magnetic core component extends to the current clamp head from the interior of the current clamp body; in such a way, the length of a magnetic path in the current clamp body is decreased; under the premise of guaranteeing a proportion between the cross section of the magnetic path and the magnetic path length, the measurement precision of the current clamp is guaranteed; and therefore, the small type current clamp for the checking of the live line measurement scene is applicable for the field of various live line measurements.