Abstract: A motor driver circuit including an inverter, a motor-drive-current detector, a current detector, and a controller operable to calculate a d-axis current difference between the detected d-axis current and a commanded d-axis current value, and a q-axis current difference between the detected q-axis current and a commanded q-axis current value. The controller is further operable on the basis of the calculated d-axis and q-axis current differences, to calculate a d-axis difference signal which is not influenced by a q-axis input voltage of the motor and which is influenced by a d-axis input voltage of the motor, and a q-axis difference signal which is not influenced by the d-axis input voltage and which is influenced by the q-axis input voltage. The controller controls the inverter, so as to zero the d-axis and q-axis difference signals.

Abstract: A variable valve timing controller includes an intake-valve and an exhaust-valve. When the engine is started, the intake-valve and the exhaust-valve are operated in a first mode in which the exhaust-valve is closed before top dead center and then the intake-valve is opened. And if a first predetermined condition is met, the intake-valve and the exhaust-valve are operated in a second mode in which the opening time of the intake-valve in the first mode is advanced before top dead center.

Abstract: An electronic control unit adjusts an electronic throttle valve to a starting opening in a cold start mode of an engine, then maintains the opening of the electronic throttle valve so that an engine rotational speed detected by a crank angle sensor increases to a target rotational speed, and increases the opening of the electronic throttle valve and retards an ignition timing if the engine rotational speed is increased above the target rotational speed.

Abstract: Two inverters (INV1, INV2) supply phase currents to three-phase coils (Y1, Y2). Although two phase currents must conventionally be measured and four current sensors are thus required, according to the present invention, the number of phase currents to be measured is reduced as a result of use of an observer for phase current estimation.

Abstract: An idle speed control apparatus for an internal combustion engine is provided which, when the internal combustion engine is started in a cold mode, provides ignition timing engine speed control (m1) such that ignition timing in which said ignition driving device performs ignition in the internal combustion engine is retarded and the engine speed of the internal combustion engine is controlled to the target engine speed, and then provides intake air quantity engine speed control (m2) such that the engine speed of the internal combustion engine is feedback-controlled to the target engine speed by controlling the intake air quantity of the internal combustion engine. As a result, it is possible to prevent the exhaust gas temperature from being increased insufficiently due to a deficiency in retard angle, and to prevent the activation of a catalytic converter from being delayed.

Abstract: Just after the start of an engine at cold start, an overlap in the opening time of an intake valve (7a) and an exhaust valve (7b) is controlled to include an intake stroke range, such that liquid fuel in an intake port (11) flows into a cylinder with the downward movement of a piston (16) without being directly exhausted to an exhaust side, so that the fuel can be combusted without fail.

Abstract: A direct-current power supply (40) is connected between the neutral points of two three-phase coils (24, 26) of a 2Y motor (22) constituted of the windings of the two three-phase coils (24, 26), which are connected in Y-connection and wound on a same stator, and to which three-phase alternating current power is severally supplied with a phase difference of a shifted angle between the windings from two inverter circuits (30, 32) having a positive pole bus (34) and a negative pole bus (36) for common use. A capacitor (38) is connected between the positive pole bus (34) and the negative pole bus (36). The electric potential difference between the neutral points of the three-phase coils (24, 26) is made larger or smaller than the voltage of the direct-current power supply (40) through the switching control of the inverter circuits (30, 32). Thereby, the capacitor (38) can be charged or discharged. Consequently, an inverter input voltage can be adjusted within a wide range.

Abstract: A motor driver circuit including an inverter, a motor-drive-current detector, a current detector, and a controller operable to calculate a d-axis current difference between the detected d-axis current and a commanded d-axis current value, and a q-axis current difference between the detected q-axis current and a commanded q-axis current value. The controller is further operable on the basis of the calculated d-axis and q-axis current differences, to calculate a d-axis difference signal which is not influenced by a q-axis input voltage of the motor and which is influenced by a d-axis input voltage of the motor, and a q-axis difference signal which is not influenced by the d-axis input voltage and which is influenced by the q-axis input voltage. The controller controls the inverter, so as to zero the d-axis and q-axis difference signals.

Abstract: A direct-current power supply (40) is connected between the neutral points of two three-phase coils (24, 26) of a 2Y motor (22) constituted of the windings of the two three-phase coils (24, 26), which are connected in Y-connection and wound on a same stator, and to which three-phase alternating current power is severally supplied with a phase difference of a shifted angle between the windings from two inverter circuits (30, 32) having a positive pole bus (34) and a negative pole bus (36) for common use. A capacitor (38) is connected between the positive pole bus (34) and the negative pole bus (36). The electric potential difference between the neutral points of the three-phase coils (24, 26) is made larger or smaller than the voltage of the direct-current power supply (40) through the switching control of the inverter circuits (30, 32). Thereby, the capacitor (38) can be charged or discharged. Consequently, an inverter input voltage can be adjusted within a wide range.

Abstract: Just after the start of an engine at cold start, an overlap in the opening time of an intake valve (7a) and an exhaust valve (7b) is controlled to include an intake stroke range, such that liquid fuel in an intake port (11) flows into a cylinder with the downward movement of a piston (16) without being directly exhausted to an exhaust side, so that the fuel can be combusted without fail.

Abstract: A sprung mass estimating apparatus applied to a vehicle having a suspension device detects a sprung mass acceleration "a" and an amount of relative displacement "s" of a sprung member relative to an unsprung member by using an acceleration sensor and a stroke sensor, respectively. The apparatus calculates a relative velocity ds/dt based on the amount of relative displacement "s". The apparatus then derives a damping force F corresponding to the relative velocity ds/dt and a set switch level of the damping coefficient, with reference to a damping force characteristic table. Based on a data row a(k), a data row s(k) and a data row F(k) (where k=1, 2, . . . , N) indicating sprung mass accelerations "a", amounts of relative displacement "s", and damping forces F obtained over such a sufficiently long time that the ratio .beta. of the spring constant to the sprung mass M can be considered constant, the apparatus calculates a sprung mass M.

Abstract: Acceleration detecting sensor (60) is provided in a sprung structure (50), while a vibration model comprising the sprung mass of a vehicle, the spring, and the shock absorber is previously stored in control unit (58). The deviation of the detected acceleration from the estimated vertical acceleration of the sprung structure is computed by a control unit (58) and then amplified. The vertical acceleration of the sprung structure and the relative velocity between sprung and unsprung structures are estimated by a control unit (58) according to the amplified deviation and the vibration model. The stored vibration model has one degree of freedom and a simple structure.

Abstract: A sprung structure is provided with an acceleration computing section. A damping force estimating section (16) of a relative velocity estimating section (12) estimates a damping force by reading information from a damping force characteristic storing section (14) in accordance with a valve opening degree instruction and the relative velocity between sprung and unsprung structures estimated in the last control cycle. An estimating and computing section 18 estimates the relative velocity between sprung and unsprung structures in accordance with the above acceleration and estimated damping force. A suspension system is controlled in accordance with the relative velocity.

Abstract: A variable valve mechanism using a non-uniform coupling in an internal combustion engine is equipped with an axis-supporting member for supporting a cam-side rotation axis in an eccentric state. In the variable valve mechanism, the axis-supporting member is driven while taking account of friction occurring in the axis-supporting member by changing the position of the axis-supporting member so as to align with the direction of a dragging torque generated between the axis-supporting member and an intermediate rotating member or between the axis-supporting member and a rotation axis member.

Abstract: In a vibration isolating device, a main chamber has a part of a wall constituted by a first elastic member to be deformed by input vibration and is filled with liquid, and a sub chamber has a part of a wall constituted by a second elastic member and is filled with liquid, and the main chamber communicates with the sub chamber through a main flow path. A liquid pressure adjusting plate is installed within the main chamber and divides the main chamber into a first chamber and a second chamber and vibrates in an opposite phase to that of the input vibration. The first chamber communicates with the second chamber through a sub flow path and the dimensions of the sub flow path is set so that the sub flow path is choked during high frequency vibration of the liquid pressure adjusting plate.

Abstract: A naphthyloxazolidone derivative of the formula: ##STR1## wherein R.sup.1 is hydrogen atom, hydroxy group, nitro group, amino group, sulfo group, aminosulfonyl group, a lower alkenyloxy group, a lower alkynyloxy group, a mono or di(lower alkyl)aminocarbonyloxy group, a lower alkanoyloxy group or a lower alkoxy group which may have a substituent selected from an aryl group, a cycloalkyl group, an oxygen-containing heteromonocyclic group, hydroxy group, a lower alkoxy group, cyano group, a di(lower alkyl)amino group, aminocarbonyl group, a lower alkoxycarbonyl group, a lower alkanoyloxy group, a lower alkylthio group, a lower alkylsulfinyl group and a lower alkylsulfonyl group; R.sup.2 is hydroxy group, a lower alkoxy group, a lower alkylsulfonyloxy group, triazo group or an amino group which may have a substituent selected from a lower alkyl group and a lower alkanoyl group, and a pharmaceutically acceptable salt thereof are disclosed.

Abstract: The invention relates to aminotetrahydronaphthalene derivatives which are intermediates for the preparation of sulfonylaminotetrahydronaphthalenes.

Abstract: A tetrahydronaphthalene derivative of the formula: ##STR1## wherein R.sup.1 is a substituted or unsubstituted phenyl group, naphthyl group, a sulfur- or nitrogen-containing heterocyclic group, a lower alkyl group or cycloalkyl group, and R.sup.2 is hydroxymethyl group, carboxyl group, a lower alkoxycarbonyl group or a group of the formula: ##STR2## wherein R.sup.3 is hydrogen atom or a lower alkyl group, R.sup.

Abstract: A naphthyloxazolidone derivative of the formula: ##STR1## wherein R.sup.1 is hydrogen atom, hydroxy group, nitro group, amino group, sulfo group, aminosulfoyul group, a lower alkenyloxy group, a lower alkynyloxy group, a mono or di(lower alkyl)aminocarbonyloxy group, a lower alkanoyloxy group or a lower alkoxy group which may have a substituent selected from an aryl group, a cycloalkyl group, an oxygen-containing heteromonocyclic group, hydroxy group, a lower alkoxy group, cyano group, a di(lower alkyl)amino group, aminocarbonyl group, a lower alkoxycarbonyl group, a lower alkanoyloxy group, a lower alkylthio group, a lower alkylsulfinyl group and a lower alkylsulfonyl group; R.sup.2 is hydroxy group, a lower alkoxy group, a lower alkylsulfonyloxy group, triazo group or an amino group which may have a substituent selected from a lower alkyl group and a lower alkanoyl group, and a pharmaceuticaly acceptable salt thereof are disclosed.

Abstract: A novel thiazolidine derivative of the formula: ##STR1## wherein R.sup.1 is a substituted or unsubstituted phenyl group, R.sup.2 is hydrogen or a lower alkyl group, R.sup.3 is hydrogen, a lower alkyl group or a lower alkanoyl group, Q is a single bond or a lower alkylene group, Alk is a lower alkylene group, Y and Z are the same or different and are oxygen atom or sulfur atom and the group of the formula: ##STR2## is either ##STR3## or a pharmaceutically acceptable salt thereof, which is useful as a cardiotonic agent is disclosed together with processes for the preparation of the compound and a pharmaceutical composition containing said compound.