Abstract: A variable reluctance-type resolver which does not deteriorate detecting accuracy, and which can fix the rotor to the rotate shaft cheaply is comprised of a stator 5 on which coils 6 are wound, a rotor provided with protrude poles 4a and an annular stopper 10 made of magnetic material. An outer diameter DS of the stopper 10 is selected to be smaller than a valley diameter DR of the rotor 4. Leakage of the magnetic flux from the stator to the stopper is prevented, and the stopper made of the magnetic material can fix the rotor in cheaper way.
Abstract: An electric steering control device is provided which is capable of enabling the driver to perform steering manipulation stably without being substantially affected by the ambient temperature and the heat generation of the control device. The control device comprises a temperature sensor for detecting the temperature of a circuit board mounting a motor drive circuit thereon and a compensation section for compensating an electric current command value based on the board temperature detected by the temperature sensor, so that en electric motor for exerting an assist force on a vehicle steering mechanism is driven by the compensated electric current command value output from a motor drive circuit. Therefore, the steering operation can be done stably without being substantially affected by the ambient temperature and the heat generation of the control device.
November 14, 2003
Date of Patent:
April 18, 2006
Toyoda Koki Kabushiki Kaisha, Toyota Jidosha Kabushiki Kaisha
Abstract: The number of the teeth of a second sun gear is slightly different from that of a first sun gear. A first planetary gears mesh with both the first sun gear and the second sun gear. A first carrier supports the first planetary. The number of the teeth of a third sun gear is same as that of the first sun gear. The second planetary gears mesh with both the second sun gear and the third sun gear. The second carrier supports the second planetary gears with preventing the same from revolving. The second power source generates a torque for rotating the first carrier.
Abstract: In a tripod-type constant velocity joint having an inner joint member, an outer joint member, and three roller units, the radius R1, outer width W1, and inner width W2 of the outer periphery cylindrical surface of each roller unit, and the radius R3 of the center hole of each roller unit are determined to satisfy the following two inequalities: 0.5Rtc(1/cos0.3??1)+(R1?R3)?<W1 1.5Rtc(1?cos0.3?)+(R1?R3)?<W2 where Rtc: the radius of a circle passing through the respective centers of tripod spherical surfaces of the inner joint member, ?: the maximum joint angle between the outer joint member and the inner joint member, and ?: coefficient of friction between each tripod spherical surface and the wall surface of the center hole of the corresponding roller unit.
Abstract: A booster circuit is equipped with booster control section that detects a power supply voltage and an actual booster voltage. The booster control section sets a target booster voltage. The booster control section 200 sets a duty ratio to eliminate a deviation between the target booster voltage and the actual booster voltage. The booster control section calculates a correction value based on an input voltage change obtained from the power supply voltage. The booster control section provides feedback control by correcting a duty ratio using the correction value, and turning on and off a transistor based on the corrected duty ratio.
Abstract: The control section can determine, on the basis of a detection signal from a detection device, whether operation of an element corresponding to the detection device has completed. The display device can display step sequence data and a three-dimensional model of a machine tool operated through simulation. When the abnormality detection section detects an abnormality of the machine tool, the control section extracts, from a ladder circuit corresponding to a step in which an abnormality has been detected, an element to be operated in response to completion of operation of a preceding element in the ladder circuit, or an element not having completed its operation. The control section then specifies a detection device corresponding to the extracted element or a moving part corresponding to the detection device, and displays the element or the moving part in the displayed three-dimensional model in a distinguishable manner.
Abstract: A grinding wheel 10 comprises a disk core 11 and a grinding stone 20 surrounding the core 11. The grinding stone 20 includes a first abrasive portion 30 and a second abrasive portion 40. The first abrasive portion forms a circumferential surface of the grinding stone 20 and has small grains. The second abrasive portion 40 forms at least one lateral surface of the grinding stone 20 and has larger grains than the first abrasive portion 30.
Abstract: A controller controls an electric motor to provide assist power corresponding to steering operation for an electric power steering apparatus. The controller comprises a detecting device, a filtering device, a judging device and a determining device. The detecting device detects present voltage of a power source for the electric motor. The filtering device filters the present voltage based on a small time-constant when the voltage of the power source increases and based on a large time-constant when the voltage of the power source decreases. The judging device judges whether the filtered voltage is lower than a predetermined threshold. And, the determining device determines being abnormality of the power source when it is judged that the filtered voltage is lower than the threshold.
Abstract: It is one object of a grinding machine and a grinding fluid supply-nozzle therefor according to the present invention to supply grinding fluid to a moving grinding point reliably, even if the surfaces of a grinding wheel is abraded up. A wheel head 5 advances/retracts to a workpiece. A grinding wheel G is carried rotatably by the wheel head 5 and grinds an eccentric portion W of the workpiece. A grinding fluid supply-nozzle 50 supplies grinding fluid to a moving grinding point K where the grinding wheel G contacts the eccentric portion W of the workpiece. The grinding fluid supply-nozzle 50 is made from a curve portion 53, an opening 51 and a straight portion 52 between the curve portion 53 and the opening 51. The grinding fluid supply-nozzle 50 spouts the grinding fluid to a grinding fluid supply point Pc upstream the grinding points K and Ks, even in the case that the grinding wheel G has been abraded up.
Abstract: In a pressure sensor which has a metal housing 12 containing a sensor chip 11 and a joint housing 14 and in which an insulating member 15 is arranged to electrically insulate both of the metal housing 12 and the joint housing 14 from each other, the metal housing 12 is connected to a stable potential such as, for example, a sensor power supply or a sensor ground. Thus, there can be solved a problem that the detection signal is liable to be influenced by electric noise from outside where a signal line of the pressure sensor and the sensor housing are electrically suspended or unfixed.
Abstract: An electric power steering apparatus includes a booster circuit and a microcomputer. The booster circuit includes a booster coil, a first FET, and a second FET. The booster coil is connected to the first FET, which is grounded. A node a between the booster coil and the first FET is connected to the second FET, which is connected to a drive circuit. The microcomputer drives the first and second FETs such that the first and second FETs are selectively turned on and off, thereby controlling an output voltage of the booster circuit. When application of assisting force to a steering system is stopped, the microcomputer holds the second FETs on until the output voltage of the booster circuit becomes equal to a predetermined voltage.
Abstract: In a torque sensor, a first detection tube (13) made from magnetic material covers a cylindrical magnetic leak prevention member (12) that is made from nonmagnetic material and covers a first shaft (3) made from magnetic material. Magnetic resistance to magnetic flux, which passes through one end of the first detection tube (13) and one end of a second detection tube (14) that is made from magnetic material and rotates together with a second shaft (4), changes according to elastic relative rotation of the two shafts (3, 4) corresponding to transmitted torque, by providing a plurality of teeth (13a, 14a) along the circumferential direction at the one end of each detection tube (13, 14). The first shaft (3) and the first detection tube (13) are integrated with the magnetic leak prevention member (12) so that they can rotate together, by being inserted in a mold for forming the magnetic leak prevention member (12) before the synthetic resin material is poured into the mold.
Abstract: A microcomputer includes a rotation angular velocity computation section, a feedback gain determination section, and a dead time compensation amount determination section. The rotation angular velocity determination section computes the rotation angular velocity of a brushless motor. Based on the rotation angular velocity, the feedback gain determination section determines feedback gains. The dead time compensation amount determination section determines a dead time compensation amount. The greater the absolute value of the rotation angular velocity, that is, the higher the rotation speed of the brushless motor, the greater the feedback gains determined by the feedback gain determination section become, and the higher the responsivity of the feedback gains becomes. The greater the absolute value of the rotation angular velocity, the smaller the dead time compensation amount determined by the dead time compensation amount determination section becomes.
Abstract: In a steering device 10, the upper side portion of a rubber boot 120 is fixedly fitted on a case outer cylindrical component 41 of a cable case 39, and the lower side portion of the rubber boot 120 is fixed to a dashboard 100 of a vehicle body 14 over the entire circumference thereof. Thus, the case outer cylindrical component 41 can be secured against rotation more firmly compared with a prior art steering device wherein such a case outer cylindrical component is fixed at two portions thereon by means of a wire of a V-letter shape. Further, the problem attendant on the wire of the V-letter shape in the prior art steering device no longer arises even in the car models wherein the case outer cylindrical component 41 and the dashboard 100 are relatively far from each other. That is, it can be realized to secure the case outer cylindrical component 41 of the cable case 39 against rotation relative to the vehicle body 14 even in any car model.
August 29, 2005
March 9, 2006
FAVESS Co., Ltd., TOYODA KOKI KABUSHIKI KAISHA, KOYO SEIKO CO., LTD., TOYOTA JIDOSHA KABUSHIKI KAISHA
Abstract: A dynamic quantity sensor device capable of measuring a dynamic quantity at a high precision and securing insulation of a pressure sensing body easily. This dynamic quantity sensor includes a pressure sensing body composed of composite ceramics in which a material having a pressure resistance effect is dispersed on a matrix made of an electrical insulation ceramic material and a pressure receiving body having an electrical insulation characteristic and disposed on a pressure receiving surface of the pressure receiving body, wherein the pressure sensing body and the pressure receiving body are integrated with each other.
Abstract: A booster includes a booster circuit and a microcomputer. The booster circuit outputs an output voltage. The output voltage is obtained by boosting a power supply voltage. The microcomputer controls the output voltage through a feedback control based on the deviation of the output voltage from a target voltage. The microcomputer determines whether the booster is in an initial state based on a start signal or a restart signal. When determining that the booster is in the initial state, the microcomputer corrects the target voltage such that the target voltage gradually increases from the power supply voltage as time elapses until a predetermined period elapses from the start of the initial state.
Abstract: A hunting detecting device used for an electrical load detecting device sets a current command value for an electrical load. Based on a deviation between a current that actually flows through the electrical load and the current command value, the hunting detecting device performs at least proportional control in a group including proportional control, integral control, and differential control. The hunting detecting device sends a current generated based on the performed control to the electrical load. A current determining device determines whether there is a current through the electrical load. When the current determining device determines that there is a current through the electrical load, a hunting detector detects a number of times of hunting within a predetermined period.
Abstract: A drive power transmission device is disclosed having a drive mechanism for transmitting a drive power between first and second rotary members rotatable relative to each other, by the operation of an electromagnetic type clutch mechanism which brings a friction clutch into connection. A magnetic path generated around an electromagnet of the electromagnetic type clutch mechanism includes a clutch magnetic path in which a magnetic flux passes to reciprocate plural times across th friction clutch, and diamond-like carbon surface treatment is given on a part or all of the friction contact surfaces of the friction clutch to form a hard amorphous carbon film thereon. Thus, the transmission device can be constructed using a smaller number of the outer and inner plates for the electromagnetic type clutch mechanism, so that it can take a small construction with a longer durability life.
Abstract: An electric power steering apparatus has a motor controlled so as to generate steering assist power according to the steering torque required to operate a steering wheel. As a result of correction of the output of the motor in accordance with a value correlating with the rotation angular velocity correspondence value of the steering wheel, in the frequency response characteristic represented by the steering frequency of the steering wheel and the amplitude ratio of the steering torque relative to the steering angle of the steering wheel, the amplitude ratio is set within a setting range, at least within the steering frequency range when a person operates the steering wheel.
Abstract: An electric power steering device according to the embodiment disclosed herein employs, in addition to a motor resolver of an electric motor for assisting the rotational manipulation of a steering shaft, first and second resolvers which are made different in the number of N-S pole pairs from each other each for detecting the rotational position of the steering shaft. The reduction gear ratio of a reduction gear mechanism of a ball screw mechanism driven by the electric motor is set so that a calculated value which is obtained by multiplying the reduction gear ratio with the number of pole pairs of a motor resolver represents a non-integer having a numerical value of the decimal place. Thus, it does not occur that calculated value becomes an integer which does not have any numerical value of the decimal place.