Drive Device for Fuel Injection Device, and Fuel Injection System

Patent metadata

Field	Value
Publication number	US-2018209366-A1
Application number	US-201815891909-A
Country	US
Kind code	A1
Filing date	Feb 8, 2018
Priority date	Jul 29, 2013
Publication date	Jul 26, 2018
Grant date	—

Abstract

A drive device capable of detecting individual variations of an injection quantity of a fuel injection device of each cylinder and adjusting a current waveform provided to an injection pulse width and a solenoid such that the individual variations of the fuel injection devices are reduced. The fuel injection device in the present invention includes a valve body that close a fuel passage by coming into contact with a valve seat and opens the fuel passage by separating from the valve seat and a magnetic circuit constructed of a solenoid, a fixed core, a nozzle holder a housing and a needle and when a current is supplied to the solenoid a magnetic suction force acts on the needle and the needle has a function to open the valve body by colliding against the valve body after performing a free running operation and changes of acceleration of the needle due to collision of the needle against the valve body are detected by a current flowing through the solenoid.

First claim

1 . A drive device for driving a fuel. injection device by controlling energization/non-energization of a solenoid of the fuel injection device,
the fuel injection device includes a valve body that closed by being brought into contact with a valve seat, and opened by being separated from the valve seat, a movable element that is driven by a magnetic suction force from the solenoid and energizes the valve body in a valve opening direction when coming into contact with the valve body, and an air gap provided between the valve body and a contact surface of the movable element and used by the movable element to come in to contact with the valve body after performing a free running operation due to the magnetic suction force from the solenoid, the drive device reduces a valve opening current which started energizing the solenoid in a state in which the valve body is closed, before the valve body starts to open.

2 . The drive device according to claim 1 ,
the drive device reduces the valve opening current before the valve body starts to open after the free running operation of the movable element toward the valve body.

3 . The drive device according to claim 1 ,
the drive device includes a step-up circuit for step up a battery voltage, the step up voltage of the step-up circuit is applied to the solenoid to supply the valve opening current, and the applying of the step up voltage is stopped before the valve body starts to open.

4 . The drive device according to claim 1 ,
the drive device opens the valve body in a state in which the valve opening current is reduced.

5 . The drive device according to claim 4 ,
the drive device supplies a current smaller than the valve opening current during a period until the valve body closes after the valve body opens.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Kusakabe Ryo
• Abe Motoyuki
• Hatanaka Ayumu
• Aono Toshihiro
• Hirotsu Teppei
• Sakamoto Hideyuki
• Toyohara Masahiro
• Mukaihara Osamu
• Fukuda Takao
• Yasukawa Yoshihito
• Miyamoto Akiyasu

Classifications

• F02D2041/2037

  for preventing bouncing of the valve needle · CPC title

• F02D41/0085

  Balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio · CPC title

• F02D2200/063

  Lift of the valve needle · CPC title

• F02M65/005

  Measuring or detecting injection-valve lift, e.g. to determine injection timing · CPC title

• F02D41/20 Primary

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