摘要:
A non-contact sensor for sensing a rotational position of a rotating object is provided. A ring-shaped permanent magnet magnetized in the axial direction is sandwiched between two pairs of magnetic plates from above and below. Two pairs of upper and lower protruded magnetic substance portions are provided between the upper and lower magnetic plates at opposite outer ends thereof. Magnetic sensitive devices are inserted in air gaps between the two pairs of upper and lower protruded magnetic substance portions. A magnetic flux generated from the ring-shaped permanent magnet is substantially concentrated to the protruded magnetic substance portions and passes the magnetic sensitive devices. The amount of magnetic flux passing each magnetic sensitive device is substantially proportional to the rotational angle of the ring-shaped permanent magnet. The rotational position of the ring-shaped permanent magnet and hence the rotational position of a rotating shaft supporting the ring-shaped permanent magnet can be sensed in a non-contact manner as a signal output from the magnetic sensitive device. Since the magnetic flux is effectively concentrated to positions where magnetic sensitive devices are attached, a non-contact rotational position sensor having high accuracy and high sensitivity can be obtained.
摘要:
A circular accelerator for extracting a charged-particle beam is arranged to increase displacement of the beam by the effect of the betatron oscillation resonance and increase the betatron oscillation amplitude of the particles, which have initially betatron oscillation within the stability limit for the resonance, to exceed the stability limit thereby extracting the particles exceeding the stability limit of the resonance.
摘要:
This invention relates to the structure of a field effect transistor, which is suitable for liquid crystal display of an active matrix scheme and there is disclosed a new structure for the field effect transistor, in which at least one of the source region and the drain region is of multi-layered structure, in which high impurity concentration portions and low impurity concentration portions are alternately superposed on each other.
摘要:
A switching control circuit includes a first field controlled thyristor having a gate and a cathode between which a backward bias voltage source and a second field controlled thyristor are connected in series. Conduction of the second field controlled thyristor is controlled by controlling a voltage applied across the gate and the cathode, thereby to control conduction of the first field controlled thyristor. A large load current can be positively and safely turned on and off by a relatively small control current or voltage.
摘要:
An improvement in a semiconductor switching device is disclosed which comprises a semiconductor substrate of a first conductivity type, an anode region of a second conductivity type formed in the semiconductor substrate adjacent to a major surface thereof, a gate region of the second conductivity type formed a distance from the anode region, and a cathode region of the first conductivity type formed in the gate region and having a higher impurity concentration than the semiconductor substrate. A channel region is formed immediately below the cathode region thereby to directly contact the cathode region to the semiconductor substrate. A current path extending from the anode region to the cathode region through the semiconductor substrate is interrupted by a depletion layer produced in the vicinity of the channel region upon application of a reverse bias across a pn-junction formed between the gate region and the cathode region. When no reverse bias voltage is applied, the anode region, the semiconductor substrate and the gate region cooperate to function as a thyristor. The semiconductor switching device has a high dv/dt capability and is easily implemented in integrated circuits.
摘要:
A semiconductor substrate having a single crystal semiconductor layer of one conductivity type exposed to the surface thereof is maintained at a temperature lower than the temperature at which the semiconductors is precipitated from the gas phase. In this state, a gas of a starting material of a semiconductor, a gas containing impurities capable of forming a semiconductor of the other conductivity type and a carrier gas therefore are fed onto the semiconductor substrate. Then, the semiconductor substrate is heated to form an amorphous or polycrystalline semiconductor layer of the other conductivity type on the semiconductor substrate. Simultaneously, the impurities of the other conductivity type are diffused from the amorphous or polycrystal semiconductor layer into the substrate which has a single crystal semiconductor layer of one conductivity type, to form a single crystal semiconductor layer having a p-n junction just below the amorphous or polycrystal semiconductor layer between the amorphous or polycrystalline semiconductor layer and the single crystal semiconductor layer of one conductivity type.In a p-n junction to be formed according to this process, the distribution of the concentration of impurities can be controlled precisely, and the step-like distribution of the concentration of impurities can be attained very well.
摘要:
An object of the present invention is to provide a small, high-power rotating electrical machine by suitably forming a distributed winding coil such that two stator magnetic poles each formed of in-phase coil turns are arranged within an electric angle of 360 degrees formed by magnetic poles of the rotor. The present invention provides a method for manufacturing a stator, the method including a first step of placing a distributed winding coil 207 composed of a wire wound around a reel 210, as a whole, inside a stator core 202, and a second step of moving an insertion blade 213 so as to spread the distributed winding coil 207 in the radial direction of the stator core 202, thus inserting the distributed winding coil 207 into a stator core slot 206.
摘要:
An object of the present invention is to provide an insulating sheet superior in heat dissipation efficiency, heat resistance, insulation efficiency and moldability. Provided is a sheet-shaped insulating sheet of a resin composition containing an epoxy resin, a curing agent and an inorganic filler, wherein one or both of the epoxy resin and the curing agent have a naphthalene structure, the inorganic filler contains hexagonal boron nitride, and the inorganic filler is contained in an amount of 70 to 85 vol % in the entire resin composition. It is possible to increase the filling efficiency of an inorganic filler in the insulating sheet by using an epoxy resin and/or a curing agent having a naphthalene structure, which are favorably compatible with the hexagonal boron nitride contained in the inorganic filler.
摘要:
An electric motor comprising a rotor having plural magnetic poles in the circumferential direction; and a stator whose teeth are disposed opposite to the periphery of the rotor, with an air gap interposed between the rotor and the stator, wherein the coil conductors are wound on the stator so that two stator magnetic poles may be formed by two coil units of a phase wound around stator teeth within the range of 360 electrical degrees subtended by the magnetic poles of the rotor; each of the two coil units forming the stator magnetic poles spans an electrical angle less than 180 electrical degrees; the two coil turns forming the two stator magnetic poles are laid out so that they may not overlap each other; and the coil conductors are so wound that the adjacent stator magnetic poles exhibit opposite magnetic polarities.
摘要:
An electric motor comprising a rotor having plural magnetic poles in the circumferential direction; and a stator whose teeth are disposed opposite to the periphery of the rotor, with an air gap interposed between the rotor and the stator, wherein the coil conductors are wound on the stator so that two stator magnetic poles may be formed by two coil units of a phase wound around stator teeth within the range of 360 electrical degrees subtended by the magnetic poles of the rotor; each of the two coil units forming the stator magnetic poles spans an electrical angle less than 180 electrical degrees; the two coil turns forming the two stator magnetic poles are laid out so that they may not overlap each other; and the coil conductors are so wound that the adjacent stator magnetic poles exhibit opposite magnetic polarities.