FUEL INJECTION DEVICE

• US 20150152824A1
• Filed: 06/07/2013
• Published: 06/04/2015
• Est. Priority Date: 06/08/2012
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.), Honda Motor Co., Ltd. (Honda Motor Company), Honda Motor Company
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.), Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Akazaki, Shusuke, Soma, Masahiro, Takaoku, Atsushi
• Granted Patent: US 9,644,587 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02D 2041/281 between sensors and control unit
• CPC Class Codes: F02D 35/023 by determining the cylinder pressure
• CPC Class Codes: F02M 2200/247 Pressure sensors
• CPC Class Codes: F02M 51/061 using electromagnetic operating means
• CPC Class Codes: F02M 51/0671 the armature having an elongated valve body attached thereto
• CPC Class Codes: F02M 57/005 the devices being sensors
• CPC Class Codes: G01L 9/00 Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements G01L11/004 takes precedence; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means measuring differences of two or more pressure values G01L13/00; measuring two or more pressure values simultaneously G01L15/00
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In a fuel injection device having a sensor for detecting a state in the combustion chamber in a free end thereof, the noises that may be generated in the sensor signal transmitting member for transmitting the sensor signal are minimized. The fuel injection device comprises: a valve body (33) having a free end exposed to the combustion chamber (7) defined in the engine main body (3) and a base end located outside of the engine main body; a sensor (38) supported at a free end of the valve body to detect a state of the combustion chamber; an actuator (37) received in the valve body; a sensor signal transmitting member (91, 128) extending from the sensor to the base end of the valve body; a drive signal transmitting member (83, 84) extending from the actuator; and a first shield member (133) interposed between the sensor signal transmitting member and the drive signal transmitting member, the first shield member having an electro-conductive property and being grounded.

Claims

1. A fuel injection device, comprising:

a valve body having a free end exposed to a combustion chamber defined in an engine main body and a base end located outside of the engine main body;

a sensor supported at the free end of the valve body to detect a state of the combustion chamber;

an actuator received in the valve body;

a sensor signal transmitting member extending from the sensor to the base end of the valve body;

a drive signal transmitting member extending from the actuator; and

a first shield member interposed between the sensor signal transmitting member and the drive signal transmitting member, the first shield member having an electro-conductive property and being grounded.

2. The fuel injection device according to claim 1, wherein the valve body is provided with an electro-conductive property and grounded via the engine main body, and the first shield member is supported by and electrically connected to the valve body.

3. The fuel injection device according to claim 2, further comprising:

a first resin portion molded to the base end of the valve body to define a connector portion;

a first connecting terminal placed in the connector portion and connected to the sensor signal transmitting member; and

a second connecting terminal placed in the connector portion and connected to the drive signal transmitting member,

the first shield member being at least partly buried in the first resin portion.

4. The fuel injection device according to claim 3, wherein the first shield member includes a part interposed between the first and second connecting terminals.

5. The fuel injection device according to claim 3, further comprising:

a second resin portion molded to the valve body and the first resin portion and covering the sensor signal transmitting member; and

a second shield member having an electro-conductive property and covering the second resin portion, the second shield member being electrically connected to a part of the first shield member extending from the first resin portion.

6. The fuel injection device according to claim 3, wherein the second connecting terminal comprises a pair of second connecting terminals which are placed on either side of a diametric line extending perpendicular to an axial line of the valve body, and the first connecting terminal is positioned on a side of one of the second connecting terminals facing away from the other second connecting terminal.

7. The fuel injection device according to claim 6, wherein a distance between the first connecting terminal and the adjoining second connecting terminal is greater than a distance between the two second connecting terminals.