Denso Corporation

Other

Toyota Jidosha Kabushiki Kaisha

Asmo Co., Ltd.

Hideji Tani

Haruyuki Urushihata

Akihiko Takenaka

Noboru Tsuge

Yoshihiro Sato

Hideji Yoshida

Takayuki Inohara

Masafuyu Sano

Seiji Morino

Toshihiro Matsuura

A valve controller includes a detector detecting a shutdown command signal to shutdown an engine, a driving circuit for driving a motor, and a power source controller. The power source controller turns on the driving circuit until the predetermined period has passed since the shutdown command signal is detected. Thus, the valve controller adjusts the valve opening/closing character in such a manner as to be suitable to an engine condition.

Valve controller

A stator having a stator core about which a coil is wound is secured to an aluminum frame. A magnet-embedded type rotor is rotatably accommodated inward of the stator. A circuit substrate is attached to the surface of the aluminum frame opposite to the surface to which the stator is secured. A control circuit and hall ICs for detecting the rotational position of the rotor are mounted on the circuit substrate. Detection signals of the hall ICs are received by the control circuit. The control circuit supplies a drive current to the coil of the stator in accordance with the detection signals.

Electric motor

The invention provides a valve controller of a motor utilizing type for improving control accuracy and reducing cost. The valve controller controls valve opening and closing of an engine by utilizing rotation torque of the motor, and has a driving circuit receiving a control signal generated by a control circuit, and applying an electric current to the motor and driving the motor on the basis of a target rotation number of the motor shown by this control signal using a frequency, and a target rotating direction of the motor shown by this control signal using a duty ratio.

The valve timing controller is driven by a motor. The valve controller has a control circuit and a driving circuit. The driving circuit receives a control signal generated by the control circuit and an engine rotation speed signal. The driving circuit supply a current to the motor to drive it based on the engine rotation speed represented by engine rotation speed signal and a target variation of the motor rotation speed represented by the control signal.

Valve timing controller

The valve controller is driven by a motor. The valve controller has a control circuit and a driving circuit. The driving circuit drives a motor based on a control signal generated by the control circuit and a rotational position signal generated by a rotational position sensor. The driving circuit generates a rotation number signal representing an actual rotation number of the motor according to the rotational position signal, and transfers the rotation number signal to the control circuit.

A valve timing controller of a motor utilizing type has a control circuit for generating a control signal, and a driving circuit for turning-on and driving the motor in accordance with the control signal generated by the control circuit. The control circuit for receiving a motor rotation signal showing the real rotation speed of the motor, and an engine speed signal showing the real rotation speed of the engine generates the control signal on the basis of the motor rotation signal when the real rotation speed of the engine is less than a reference value. The control circuit also generates the control signal on the basis of the engine speed signal when the real rotation speed of the engine becomes the reference value or more.

A valve opening and closing control device of a type making use of a motor enhances driving performance of the motor and restricts heat generated by constituent elements. A bridge circuit of a motor driving circuit comprises three rows of arms comprising two switching elements connected in series to each other and two diodes connected in parallel to corresponding switching elements. The respective arms are connected in parallel to an electric source, and motor windings are connected to points of interconnection of the switching elements on the respective arms. After putting the respective switching elements of the arms in an ON state to carry an electric current to the windings, a control circuit causes the switching element in an ON state to be put as an electricity introduction stoppage element in an OFF state and causes the switching element of the same arm as that, on which the electricity introduction stoppage element is disposed, to be put in an ON state.

Motor drive apparatus

A valve timing controller is driven by a motor and has a control circuit and a driving circuit. The driving circuit drives the motor according to a target rotation speed which is represented by a control signal frequency generated by the control circuit. Accordingly as the frequency becomes higher, the target rotation speed increases. When the frequency of the control signal is either lower than or equal to a first threshold frequency, or higher than or equal to a second threshold, the first threshold frequency being greater than zero and being greater than the second threshold frequency, the driving circuit stops supplying current to the motor.

The variable valve timing controller controls the valve timing of the intake valve. The variable valve timing controller has a shaft, the stator fixed on the engine and generating the magnetic field around the shaft and rotational phase converter converting the torque applied to the shaft. When the valve timing is in the most delayed timing, the engine can be started. The rotational phase of this timing is called the feasible phase. When the stator stops generating the magnetic field, the load torque arise on the shaft. The rotational phase converter varies the rotational phase into the feasible phase with receiving the load torque from the shaft.

Growing community of inventors

Hashima-gun, Japan

Hideji Tani