摘要:
A position detection apparatus and a medical-device-position detection system that have improved position detection accuracy are provided by setting high amplification for the position detection apparatus. The position detection apparatus includes a circuit that has at least one embedded coil (10a) and that is provided inside an object (10) to be detected; a first magnetic-field generating unit (11) for generating a first magnetic field in the region where the embedded coil (10a) is disposed; a magnetic-field detecting unit (5, 12) for detecting an induced magnetic field generated at the embedded coil (10a) by the first magnetic field; and a second magnetic-field generating unit (23) for generating a second magnetic field having a phase substantially opposite to the phase of the first magnetic field.
摘要:
There are provided a position detection system, a guidance system, and a position detection method which obviate the need for frequency adjustment of an alternating magnetic field used in position detection of a device and which allow the device to be made more compact and less expensive. There are included a device (capsule endoscope 20) provided with a magnetic induction coil, a drive coil 51 for generating an alternating magnetic field, a plurality of magnetic sensors 52 for detecting an induced magnetic field, a frequency determining section 50B for determining a position calculating frequency based on a resonance frequency of the magnetic induction coil, and a position analyzing unit 50A for calculating, at the position calculating frequency, at least one of the position and the orientation of the device 20 based on the difference between outputs from the magnetic sensors 52 when only the alternating magnetic field is applied and outputs from the magnetic sensors 52 when the alternating magnetic field and the induced magnetic field are applied; and at least one of a frequency range of the alternating magnetic field and an output frequency range of the magnetic field sensors is limited based on the position calculating frequency.
摘要:
A self-starting type axial gap synchronous motor includes a stator in which plural small stators are arranged on the same circumference; disc-shaped rotors in each of which plural permanent magnets facing the stator are arranged on the same circumference; and a shaft coupled to the rotors. Each of the disc-shaped rotors includes a metal frame that is provided so as to surround the plural permanent magnets arranged on the same circumference, and each of the metal frames is configured using a nonmagnetic and conductive material.Accordingly, it is possible to obtain a self-starting type axial gap synchronous motor that can be started by a commercial electric power without using an inverter, and a compressor and a refrigeration cycle apparatus using the same.
摘要:
A current instruction generation unit generates a d-axis current instruction and a q-axis current instruction based on a torque instruction for an AC motor, using a map in which a current instruction capable of lowering noise (vibration and sound noise) (low-noise current instruction) generated from the AC motor is determined in advance for each torque of the AC motor. Then, a signal for driving an inverter is generated based on the generated d-axis current instruction and the q-axis current instruction.
摘要:
When an ECU receives a transmission signal having a high level from a transmission, the ECU exerts torque reduction control to reduce a torque control value for a motor generator. Furthermore the ECU sets an optimum (or target) value of a voltage as based on the torque control value and a motor rotation speed and controls an upconverter. Herein, when the transmission is shifting gears, the ECU controls the upconverter to allow the voltage to be constant regardless of whether the torque reduction control is exerted to reduce the torque control value.
摘要:
In the rectangular-wave voltage control mode, torque feedback control, in which the voltage phase of the rectangular-wave voltage is adjusted based on the deviation of the torque estimated value from the torque command value, is performed. A torque estimation portion calculates the torque estimated value using the motor currents calculated based on the values detected by a current sensor and a rotational position sensor, as in the case of the PWM control mode. Namely, the same state quantity (quantity detected by the sensors) of the alternating-current motor is used in the motor control in both the rectangular-wave voltage control mode and the PWM control mode.
摘要:
Disclosed is a sintered gear composed of a sintered alloy having a metal matrix and pores. The tooth surface (2, 3, 4) of the tooth and the bottom land (5) have a densified layer (11) in which the porosity is reduced to 10% or less from the sintered alloy. The densified layer at the tooth surface is formed with a thickness of 300 to 1,000 microns, and the densified layer at the bottom land is formed with a thickness of 10 to 300 microns. The boundary surface of the densified layer is continuous from the tooth surface side to the bottom land side so as not to have a substantial level difference.
摘要:
An electrically powered vehicle includes a motor generator configured to be capable of transmitting and receiving torque to and from a driving shaft coupled to a driving wheel; a DC power supply including a power storage device; and an inverter for performing bidirectional DC/AC power conversion between the DC power supply and the motor generator. The MG-ECU controls a plurality of power semiconductor switching elements to be turned on/off in accordance with a torque command value and a state value of the motor generator. When an accelerator pedal is released, the MG-ECU controls the inverter to superimpose a DC current component on an AC current of each phase in the motor generator in accordance with the state of charge of the power storage device.
摘要:
Disclosed is a sintered gear composed of a sintered alloy having a metal matrix and pores. The tooth surface (2, 3, 4) of the tooth and the bottom land (5) have a densified layer (11) in which the porosity is reduced to 10% or less from the sintered alloy. The densified layer at the tooth surface is formed with a thickness of 300 to 1,000 microns, and the densified layer at the bottom land is formed with a thickness of 10 to 300 microns. The boundary surface of the densified layer is continuous from the tooth surface side to the bottom land side so as not to have a substantial level difference.
摘要:
A ball grid array type semiconductor device comprises a bare chip, metal-filled through hole portions connected to internal electrodes of the bare chip, inner leads and a flexible tape carrier having external electrodes. The internal electrode of the bare chip has a length in a direction perpendicular to a side of the chip, which is three times or more the pitch of adjacent internal electrodes. The through hole portions are connected respectively to the internal electrodes so that the through hole portions are arranged in three or more rows. The inner lead led from the through hole portion in the intermediate row is spaced apart from an adjacent through hole portion so as not to interfere with it.