Electromagnetic valve driving device

Patent metadata

Field	Value
Publication number	US-11448174-B2
Application number	US-202117405502-A
Country	US
Kind code	B2
Filing date	Aug 18, 2021
Priority date	Sep 30, 2020
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

Abstract

An electromagnetic valve driving device which drives a fuel injection valve having a solenoid coil, includes: a regenerative switching element disposed between a first end portion of the solenoid coil and the ground; and a control unit configured to control the regenerative switching element to be in an ON state or an OFF state, wherein the control unit includes: a voltage detection unit configured to detect a voltage of the first end portion of the solenoid coil; and an abnormality detection unit configured to detect an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit.

First claim

What is claimed is:

1. An electromagnetic valve driving device which drives a fuel injection valve having a solenoid coil, comprising:
a regenerative switching element disposed between a first end portion of the solenoid coil and a ground; and
a control unit configured to control the regenerative switching element to be in an ON state or an OFF state,
wherein the control unit includes:
a voltage detection unit configured to detect a voltage of the first end portion of the solenoid coil; and
an abnormality detection unit configured to detect an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit.

2. The electromagnetic valve driving device according to claim 1 ,
wherein the control unit includes a drive control unit configured to control the regenerative switching element to be in an ON state or an OFF state, and
wherein the abnormality detection unit detects an abnormality of the regenerative switching element on the basis of the voltage detected by the voltage detection unit when the drive control unit controls the regenerative switching element to be in an ON state.

3. The electromagnetic valve driving device according to claim 2 ,
wherein the abnormality detection unit detects an abnormality of the regenerative switching element when the voltage detected by the voltage detection unit is a prescribed value or higher before the fuel injection valve is driven.

4. The electromagnetic valve driving device according to claim 3 , further comprising:
a boost circuit configured to step up a battery voltage which is an output voltage of a battery;
a first switching element disposed between the boost circuit and the first end portion of the solenoid coil;
a second switching element disposed between the battery and the first end portion;
a third switching element disposed between a second end portion of the solenoid coil and a ground; and
a first switch which is disposed between the second end portion and a ground and is different from the third switching element,
wherein, when the voltage detected by the voltage detection unit is the prescribed value or higher, the abnormality detection unit detects an abnormality of the regenerative switching element if both of the regenerative switching element and the first switch are in an ON state.

5. The electromagnetic valve driving device according to claim 4 , further comprising:
a bootstrap capacitor configured to generate a voltage required for turning on the first switching element and the second switching element; and
a second switch disposed between the bootstrap capacitor and a ground,
wherein the drive control unit controls the second switch to be in an ON state to cause the bootstrap capacitor to be charged with electricity, and
when the second switch is in an OFF state and both of the regenerative switching element and the first switch are in an ON state, the abnormality detection unit detects an abnormality of the regenerative switching element if the voltage detected by the voltage detection unit is the prescribed value or higher.

6. The electromagnetic valve driving device according to claim 1 , wherein the control unit stops the driving of the fuel injection valve when an abnormality of the regenerative switching element is detected.

Assignees

• Hitachi Astemo Ltd
• Nuvoton Technology Corp Japan

Inventors

• Kato Motoaki
• Ogawa Atsushi
• Nomura Kengo
• Kuroda Keisuke

Classifications

• F02D41/20 Primary

  Output circuits, e.g. for controlling currents in command coils · CPC title

• F02D2041/2013

  by using a boost voltage source · CPC title

• F02D2041/2093

  detecting short circuits · CPC title

• F02D2041/2044

  using pre-magnetisation or post-magnetisation of the coils · CPC title

• F02D2041/2006

  by using a boost capacitor · CPC title