Fuel injection device

• US 9,541,046 B2
• Filed: 01/10/2014
• Issued: 01/10/2017
• Est. Priority Date: 01/24/2013
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Yasukawa, Yoshihito, Ehara, Hideharu, Ishikawa, Tohru, Abe, Motoyuki, Kusakabe, Ryo
• Primary Examiner(s): HWU, DAVIS D
• Application Number:
  US14/763,029
• Publication Number:
  US 20150354515A1
• Time in Patent Office: 1,096 Days
• Field of Search: 239/585.1, 2395853-5855
• US Class Current: 1/1
• CPC Class Codes: F02D 41/20 Output circuits, e.g. for controlling currents in command coils
• CPC Class Codes: F02M 2200/08 Fuel-injection apparatus having special means for influencing magnetic flux, e.g. for shielding or guiding magnetic flux
• CPC Class Codes: F02M 45/00 Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship pumps having such delivery by means of delivery valves F02M59/462
• CPC Class Codes: F02M 45/08 Injectors peculiar thereto
• CPC Class Codes: F02M 51/061 using electromagnetic operating means
• CPC Class Codes: F02M 51/0625 characterised by arrangement of mobile armatures
• CPC Class Codes: F02M 51/0657 the body being hollow and its interior communicating with the fuel flow
• CPC Class Codes: F02M 51/066 the armature and the valve being allowed to move relatively to each other or not being attached to each other
• CPC Class Codes: F02M 61/04 having valves , e.g. having a plurality of valves in series
• CPC Class Codes: F02M 61/10 Other injectors with elongated valve bodies, i.e. of needle-valve type
• CPC Class Codes: F02M 61/20 Closing valves mechanically, e.g. arrangements of springs or weights or permanent magnets; Damping of valve lift

Abstract

A fuel injection valve having a variable stroke mechanism is constructed. A valve body provided to be slidable; a first movable element for cooperating with the valve body; an inner fixed iron core provided at a position to oppose a second movable element; an outer fixed iron core; and a coil are included. A lift amount of the second movable element is set larger than a lift amount of the first movable element, and a portion of the second movable element is projected into the first movable element. In this way, large and small lifts are constituted by using a difference between magnetic attractive forces that are generated in the first movable element and the second movable element by a current supplied to the coil.

Claims

1. A fuel injection valve comprising:

a valve body;

a movable element for moving the valve body;

a fixed iron core provided at a position to oppose the movable element;

a valve seat member formed with a valve seat; and

a coil for displacing the movable element and causing the valve body to be seated on or unseated from the valve seat, wherein

the movable element moves the vale body and is constructed of a first movable element and a second movable element, the valve body is a two stroke valve body that is configured to be moved by movement of the first movable element, and the two stroke valve body is configured to be moved by movement of the second movable element independent of any movement of the first movable element.

2. The fuel injection valve according to claim 1 wherein a first current is applied to the first movable element, and a second current is applied to the second movable element, the second current having a greater magnitude than the first current such that movement of the valve body by the second movable element results in a larger stroke than a stroke caused by movement of the valve body by the first movable element.

3. The fuel injection valve according to claim 1 wherein the second movable element is arranged on the valve body side from the first movable element, and a portion of the second movable element is projected into the first movable element.

4. The fuel injection valve according to claim 1 wherein a surface of the fixed iron core that corresponds to the two movable elements is divided into an inner peripheral side and an outer peripheral side in a radial direction.

5. The fuel injection valve according to claim 1 wherein a waveform of a drive current that is supplied to the fuel injection valve when the two movable elements are moved varies in accordance with a moving amount.

6. The fuel injection valve according to claim 1 wherein the first movable element and the second movable element are configured to contact the fixed iron core when being moved.

7. The fuel injection valve according to claim 1 wherein the second movable element is configured to be integrated with the valve body.

8. The fuel injection valve according to claim 1 wherein the first movable element causes the valve body to be moved by contacting the second movable element when being moved.

12. The fuel injection valve according to claim 1 wherein the first movable element and the second movable element are configured to contact the fixed iron core when being lifted.

13. The fuel injection valve according to claim 1 wherein the second movable element is configured to be integrated with the valve body.

14. The fuel injection valve according to claim 1 wherein the first movable element causes the valve body to be lifted by contacting the second movable element when being lifted.

16. The fuel injection valve according to claim 7, wherein the valve body is configured to be lifted by lifting of the first movable element, and the valve body is configured to be lifted by lifting of the second movable element.

9. A fuel injection valve comprising:

a two stroke valve body;

a movable element having multiple movable elements that move the valve body;

a fixed iron core provided at a position to oppose the movable element;

a valve seat member formed with a valve seat; and

a coil for displacing the movable element and causing the valve body to be seated on or unseated from the valve seat, wherein

the movable element is constructed of a first movable element and a second movable element, and

the first movable element and the second movable element are movable independently.

10. The fuel injection valve according to claim 9, wherein different currents are applied to each of the multiple movable elements, the different currents causing the multiple movable elements to move by different amounts, such that the different amounts of movement of the multiple movable elements lead to different stroke amounts of fuel by the fuel injection valve.

11. The fuel injection valve according to claim 9 wherein the second movable element is arranged on the valve body side from the first movable element, and a portion of the second movable element is projected into the first movable element.

15. A fuel injection valve comprising:

a valve body;

a movable element for moving the valve body;

a fixed iron core provided at a position to oppose the movable element;

a valve seat member formed with a valve seat; and

a coil for displacing the movable element and causing the valve body to be seated on or unseated from the valve seat, wherein

the movable element is configured to move the valve body for a first length by a flow of a first current through the coil and move the valve body for a second length that is longer than the first length by a flow of a second current that is larger than the first current through the coil.

17. The fuel injection valve according to claim 15 wherein a lift amount of the second movable element is larger than a lift amount of the first movable element.

18. The fuel injection valve according to claim 15 wherein the second movable element is arranged on the valve body side from the first movable element, and a portion of the second movable element is projected into the first movable element.

19. The fuel injection valve according to claim 15 wherein a surface of the fixed iron core that corresponds to the two movable elements is divided into an inner peripheral side and an outer peripheral side in a radial direction.

20. The fuel injection valve according to claim 15 wherein a waveform of a drive current that is supplied to the fuel injection valve when the two movable elements are lifted varies in accordance with the lift amount.