PLUG CAP

• US 20120322280A1
• Filed: 02/23/2011
• Published: 12/20/2012
• Est. Priority Date: 02/24/2010
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Kitamura, Ryohei, Yamamoto, Takao, Fuma, Tomohiro, Ohta, Junpei, Sonoda, Yutaka
• Granted Patent: US 8,851,915 B2
• Time in Patent Office: Days
• US Class Current: 439/125
• CPC Class Codes: F02P 13/00 Sparking plugs structurally combined with other parts of internal-combustion engines connection of ignition coil to spark plug connector F02P3/02; with fuel injectors F02M57/06 ; spark plug connector per se H01T13/04 – H01T13/06; predominant aspects of sparking plug, see H01T13/40 – H01T13/44
• CPC Class Codes: H01T 13/06 Covers forming a part of the plug and protecting it against adverse environment

Abstract

One object of the invention is to provide a plug cap that more reliably prevents the leakage of current by suppressing the ingress of water from a gap between a terminal body and a rubber member.

A plug cap 1 includes an electrical connection portion 5 that electrically connects a spark plug to a plug cord, a terminal body 2 that is provided on the outer periphery of the electrical connection portion 5, and a cylindrical rubber member 3 which is mounted on at least one of one end portion and the other end portion of the terminal body 2 and into which the spark plug or the like is inserted. The terminal body 2 includes a one end-side insertion portion 41 which is formed at one end of the terminal body and into which the spark plug is inserted and the other end-side insertion portion 42 which is formed at the other end of the terminal body and into which the plug cord is inserted. The rubber member 3 includes an inner cylindrical portion 31 that is inserted into the one end-side insertion portion 41 or the other end-side insertion portion 42, and a cylindrical outer cylindrical portion 32 that is positioned close to the outer periphery of the inner cylindrical portion 31. The inner cylindrical portion 31 includes annular protrusions 35 that come into contact with the inner peripheral surface of the terminal body 2.

Claims

1-6. -6. (canceled)

7. A plug cap comprising:

an electrical connection portion that electrically connects a spark plug to a plug cord, the spark plug being connected to one end of the electrical connection portion and the plug cord being connected to the other end of the electrical connection portion;

a terminal body that is made of a resin, is provided on an outer periphery of the electrical connection portion, and includes a one end-side insertion portion which is formed at one end of the terminal body and into which the spark plug is inserted and the other end-side insertion portion which is formed at the other end of the terminal body and into which the plug cord is inserted, at least the one end-side insertion portion and the other end-side insertion portion being formed in a cylindrical shape; and

a cylindrical rubber member which is mounted on at least one of one end portion and the other end portion of the terminal body and into which the spark plug or the plug cord is inserted,

wherein the rubber member includes a cylindrical inner cylindrical portion that is inserted into the one end-side insertion portion or the other end-side insertion portion of the terminal body, a cylindrical outer cylindrical portion that is positioned close to the outer periphery of the inner cylindrical portion and is disposed with the terminal body interposed between the outer cylindrical portion and the inner cylindrical portion, and a connecting portion that connects the outer cylindrical portion to the inner cylindrical portion, and

the inner cylindrical portion includes an annular protrusion that comes into contact with the inner peripheral surface of the terminal body.

8. The plug cap according to claim 7,

wherein the rubber member is mounted on the one end portion of the terminal body, the electrical connection portion includes a connector bracket of which one end portion comes into contact with the spark plug, and

a leading end portion of the inner cylindrical portion, which faces the other end of the terminal body, extends to one end face of the connector bracket or is positioned closer to the other end portion of the terminal body than the one end face of the connector bracket.

9. The plug cap according to claim 7,

wherein at least one of the annular protrusion, which is provided at the inner cylindrical portion, is formed on the inner cylindrical portion in a range of the length of the outer cylindrical portion.

10. The plug cap according to claim 9,

wherein the spark plug includes:

a cylindrical metal shell; and

an insulator which is inserted into the metal shell and of which a rear end-side body portion is exposed from the metal shell,

a step portion and a cylindrical portion, which is positioned closer to the metal shell than the step portion, are formed on the outer periphery of the rear end-side body portion, and the rear end-side body portion is inserted into the one end-side insertion portion when the plug cap is connected to the spark plug,

the rubber member is mounted on the one end portion of the terminal body, and

the annular protrusion is formed on the inner cylindrical portion at a position that faces the cylindrical portion of the rear end-side body portion when the plug cap is connected to the spark plug.

11. The plug cap according to claim 7,

wherein a length of the inner cylindrical portion from the connecting portion is larger than a length of the outer cylindrical portion from the connecting portion.

12. The plug cap according to claim 7,

wherein a reduced-diameter portion, of which a diameter is reduced stepwise and/or continuously toward an opposite end portion of the terminal body opposite to the end portion of both end portions of the terminal body on which the rubber member is mounted, is formed at a leading end portion of the outer cylindrical portion facing the opposite end portion.