Valve control device and valve system

Patent metadata

Field	Value
Publication number	US-10280834-B2
Application number	US-201615559961-A
Country	US
Kind code	B2
Filing date	Mar 24, 2016
Priority date	Mar 26, 2015
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A valve control device includes a drive circuit for supplying a drive signal to an actuator adjusting an opening degree of a valve via a prescribed transmission line, generates a PWM signal on the basis of a target opening degree supplied from the outside and a sensor signal that indicates a real opening degree of the valve, and supplies the PWM signal to the drive circuit. The valve control device includes a disconnection detection unit which detects, on the basis of the PWM signal and a monitor signal of the drive signal, whether the transmission line is disconnected.

First claim

The invention claimed is:

1. A valve control device which has a drive circuit supplying a drive signal to an actuator adjusting a degree of opening of a valve via a predetermined transmission line, generates a PWM signal on the basis of a target degree of opening supplied from an outside and a sensor signal indicating a real degree of opening of the valve, and supplies the generated PWM signal to the drive circuit, wherein the drive circuit includes a self-diagnostic function of diagnosing its own soundness, the valve control device comprising:
a disconnection detecting unit configured to detect, on the basis of the PWM signal and a monitor signal of the drive signal, whether the transmission line is disconnected, and the disconnection detecting unit detects the disconnection of the transmission line on the basis of a result of self-diagnosis of the drive circuit in addition to the PWM signal and the monitor signal of the drive signal.

2. The valve control device according to claim 1 , wherein the disconnection detecting unit acquires a monitor voltage of the drive signal as the monitor signal, and determines that the transmission line is disconnected when a state in which the monitor voltage is lower than or equal to a predetermined voltage threshold and the duty ratio of the PWM signal is higher than or equal to a predetermined DUTY threshold continues for a predetermined evaluation time.

3. The valve control device according to claim 1 , wherein the disconnection detecting unit acquires a monitor voltage of the drive signal as the monitor signal, and determines that the transmission line is disconnected when, after a state in which the monitor voltage is lower than or equal to a predetermined voltage threshold and the duty ratio of the PWM signal is higher than or equal to a predetermined DUTY threshold continues for a predetermined first evaluation time, a sound state of the drive circuit continues for a predetermined second evaluation time.

4. The valve control device according to claim 1 , wherein the valve is a wastegate valve provided for a supercharger for the engine.

5. The valve control device according to claim 1 , wherein,
when the actuator is a motor,
the disconnection detecting unit calculates an effective drive duty ratio excluding influence of a back electromotive force generated from a duty ratio of the PWM signal by the motor, and compares the effective drive duty ratio with the DUTY threshold.

6. A valve system comprising:
a valve;
an actuator; and
the valve control device according to claim 1 .

7. A valve control device which has a drive circuit supplying a drive signal to an actuator adjusting a degree of opening of a valve via a predetermined transmission line, generates a PWM signal on the basis of a target degree of opening supplied from an outside and a sensor signal indicating a real degree of opening of the valve, and supplies the generated PWM signal to the drive circuit, the valve control device comprising:
a disconnection detecting unit configured to detect, on the basis of the PWM signal and a monitor signal of the drive signal, whether the transmission line is disconnected,
when the actuator is a motor, the disconnection detecting unit calculates an effective drive duty ratio excluding influence of a back electromotive force generated from a duty ratio of the PWM signal by the motor, and compares the effective drive duty ratio with the DUTY threshold.

Assignees

• Keihin Corp
• Honda Motor Co Ltd

Inventors

• Ito Hiroshi
• Yahagi Takuya
• SHIKINE Youichiro
• Ichikawa Tomohide
• Yamamoto Kensuke
• Inoue Akihito

Classifications

• H02P2209/09

  PWM with fixed limited number of pulses per period · CPC title

• F02B37/18

  by bypassing exhaust {from the inlet to the outlet of turbine or to the atmosphere} · CPC title

• F02D2250/16

  End position calibration, i.e. calculation or measurement of actuator end positions, e.g. for throttle or its driving actuator · CPC title

• Y02T10/144

  Cross-Sectional Technologies · mapped topic

• G05B9/02

  electric · CPC title