JP2011151181A - Ignition coil for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition coil that eliminates the occurrence of a defect due to welding or solder by employing neither welding nor soldering etc., and is easily assembled. <P>SOLUTION: The ignition coil for an internal combustion engine is characterized in that a primary coil terminal 16b and an igniter terminal 22a, and a connector 24a have the same protruding direction, the primary coil terminal 16b and igniter terminal 22a, and connector terminal 24a are connected so as to actualize electric conduction among them, and the primary coil terminal 16b and igniter terminal 22a, and connector terminal 24a are connected by a joint terminal 28. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a connection structure of a connector terminal, an igniter terminal, and a primary bobbin terminal of an ignition coil for an internal combustion engine.

Conventionally, a coil part composed of a primary coil, a secondary coil and an iron core, an igniter for supplying a primary voltage and an ignition signal to the coil part, and the igniter and an external battery are connected to the coil housing part of the case. In an internal combustion engine ignition coil that includes a connector that is filled with mold resin in the coil housing portion of the case, several methods for electrically connecting the connector terminal, igniter terminal, primary bobbin terminal, or secondary coil terminal have been proposed. As for the connection between the terminals of the ignition coil, several configurations have been proposed for the purpose of easy connection and improved reliability. As a typical example of this, for example, in Japanese Patent Application Laid-Open No. 11-050938 (hereinafter “Patent Document 1”), in a closed magnetic circuit type ignition coil including a primary coil, a secondary coil, an iron core, an igniter, and a connector, The connecting terminals of the igniter are taken out in parallel from the igniter body on substantially the same virtual take-out plane, and at least one of the adjacent connecting terminals is bent after taking out from the igniter body, and is connected to the external terminal in the ignition coil. There has been proposed an ignition coil in which a virtual straight line connecting adjacent electrical connection portions of the connection terminals to be electrically connected intersects the virtual take-out plane and is subjected to resistance welding.

As another example, Japanese Patent Application Laid-Open No. 11-062800 (hereinafter “Patent Document 2”) discloses an electronic control device for an internal combustion engine in an ignition coil for an internal combustion engine that generates a high voltage to be applied to the ignition device for the internal combustion engine. A plurality of connector terminals that are electrically connected to each other, an igniter body housed in the ignition coil, and a plurality of connection terminals that are taken out in parallel on substantially the same virtual take-out plane from the igniter body. A connecting terminal having at least one connecting terminal having a different length from the other connecting terminal, and a plurality of electrical connecting portions for electrically connecting the connector terminal and the connecting terminal in the ignition coil, At least one of the electrical connections adjacent to each other on the virtual take-out plane is different in distance from the other electrical connection and the igniter body. Even ignition coil was resistance welding and a connecting portion provided at the intersection of the terminal and the connector terminal have been proposed.

JP 11-050938 A Japanese Patent Laid-Open No. 11-062800

However, the conventional ignition coil has the following problems. That is, in the ignition coil of the above-mentioned Patent Document 1, the connecting terminals of the igniter are taken out and bent alternately so as to intersect with each other. However, because of variations in welding or soldering, the adjacent terminals are mistakenly connected or the terminals are connected. There is a problem that reliability cannot be maintained due to a failure such as inaccurate connection.

Further, in the ignition coil of Patent Document 2, the connector terminal or the igniter terminal is taken out on a plane and the length of one of the terminals is increased to increase the interval between the electrical connection portions. Since there are a plurality of terminals, there is a variation in welding or soldering. Therefore, there is a problem that reliability cannot be maintained due to a problem that the adjacent terminals are erroneously connected or the terminals cannot be correctly connected.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an ignition coil that can be easily assembled by eliminating the occurrence of defects due to welding or soldering without using welding or soldering.

In order to solve the above problems, the present invention is configured as follows. That is, according to the first aspect of the present invention, a coil portion comprising a primary coil, a secondary coil, and an iron core in a coil housing portion of the case, an igniter for supplying a primary voltage and an ignition signal to the coil portion, An ignition coil for an internal combustion engine comprising a connector for connecting an igniter and an external battery, wherein a coil housing portion of the case is filled with mold resin, and at least the input terminal and the output terminal of the primary coil and the secondary coil The terminal connected to the igniter terminal, the terminal of the connector, and the terminal of the igniter have a substantially flat metal terminal, the respective terminals have the same projecting direction, and the respective terminals are The ignition coils are connected so as to realize electrical continuity between the respective terminals, and the respective terminals are connected by joint terminals.

In the above configuration, each of the terminals may be formed with a groove for preventing disconnection for fitting the joint terminal in at least one place. The joining terminal may be press-fitted into a holder made of resin or the like, the joining terminal holding part for holding the joining terminal in the holder, and when the joining terminal is press-fitted into the holder You may form the bending part etc. which are hold | maintained to. In order to prevent the joining terminal from coming off the holder, the widest length L1 of the bent portion may be longer than the distance L2 between the joining terminal holding part and the joining holding part. Further, conductive silicon or the like may be injected into the holder into which the joining terminal is press-fitted to ensure electrical continuity even after filling with the mold resin.

As described above, by connecting the igniter terminal, the connector terminal, and the primary coil terminal or the secondary coil terminal with the joining terminal, there is no variation in the joining state, the occurrence of defects can be suppressed, and the assembly is facilitated. An ignition coil can be realized.

1 is a perspective view of an ignition coil according to an embodiment of the present invention. It is side surface sectional drawing of the ignition coil made into the Example of this invention. It is the A section enlarged view of FIG. It is a perspective view of the electrical connection part of a connector, an igniter, and a coil. It is a perspective view of the junction terminal inserted in the holder. It is a perspective view of the junction terminal after press work. It is a perspective view of the junction terminal cut by the tie bar.

The present invention is particularly characterized in the connection structure between the connection terminals derived from the primary coil, the igniter, and the connector, and it is easy to use the terminal joining member without welding or soldering between these respective terminals. It is characterized by having a connectable structure. The terminals connected by the joining member include a connector terminal-igniter terminal, a connector terminal-primary coil terminal, or a combination of these three types of signals, ground, power supply terminal, and the like. The number of sheets and this combination can be changed.

FIG. 1 is a perspective view of an ignition coil according to an embodiment of the present invention, and FIG. 2 is a side sectional view of FIG. In the ignition coil of the present invention, a coil portion is arranged outside a plug hole formed in an upper portion of an engine (not shown), and a high voltage generated from the coil portion is supplied to the ignition plug via a conductive member.

In FIGS. 1 and 2, the case 14 forming the coil portion of the ignition coil 10 is made of a resin and has a box shape. The case 14 is provided with a case fixing portion 15 for fixing to the engine. The case 14 includes an igniter 22 for controlling the ignition operation of the ignition coil, and an iron core 20 so that at least a part of the case 14 is accommodated. The outer side of the iron core 20 has an outer periphery of the primary bobbin 16a. A primary coil 16 in which the primary winding 16c is wound about 100 turns, and a secondary coil 18b is wound around the outer periphery of the secondary bobbin 18a on the outer side of the primary coil 16 by about 8000 to 15000 turns. The coil 18 is disposed, and in the final stage of the assembly process, the case is filled with a thermosetting mold resin so that the components are fixed and insulated. In the above configuration, the igniter 22 is vertically placed in a direction perpendicular to the opening surface of the case 14, and the terminal extending direction is substantially parallel to the side surface of the case 14, thereby reducing the dimension in the height direction of the case 14. This makes it possible to suppress the connection and facilitates the connection between the connector terminal and the coil terminal.

Further, a connector 24 for connecting a battery (not shown) and an ignition coil control unit such as an external ECU is provided on one outer peripheral side surface of the case 14.

Next, a connection structure between the terminals of the ignition coil according to the embodiment of the present invention will be described. In the present embodiment, the connection terminals derived from the primary coil 16, the igniter 22, and the connector 24 are connected by a joining member. This specific structure is described below. 3 is an enlarged view of a portion A in FIG. 2, and FIG. 4 is a perspective view of an electrical connection portion of the connector, the igniter, and the primary coil. 2 to 4, the primary coil terminal 16b has a terminal connected to the igniter terminal 22a, the connector terminal 24a and the igniter terminal 22a having a substantially flat metal terminal, and the primary coil terminal. 16b, the igniter terminal 22a, and the connector terminal 24a have the same protruding direction. The primary coil terminal 16b, the igniter terminal 22a, and the connector terminal 24a are connected so as to achieve electrical continuity between them. Further, the primary coil terminal 16b, the igniter terminal 22a, and the connector terminal 24a are connected by a joining terminal 28. Further, the joining terminal 28 is formed of a conductive member such as a metal having elasticity. Further, a portion 26 where the primary coil terminal 16b, the igniter terminal 22a and the connector terminal 24a of the connector terminal 24a come into contact with each other is formed with a groove portion 26 for preventing the primary coil terminal 16b from engaging with the portion. The groove 26 is preferably provided so as to dig a groove in the flat surface of each terminal, but may be formed by other means. In addition, the groove portion 26 is provided to prevent the joining terminal 28 from coming off from each terminal, but the removal preventing structure is not limited to the formation of the groove 26 as described above, and the joining terminal 28 is directly attached to the case. It is good also as a structure engaged.

Next, FIG. 5 is a perspective view of the connection terminal in which the joint terminal 28 is inserted into the holder 12, and FIGS. 6 and 7 are perspective views of the joint terminal 28 before the holder 12 is assembled. 5 to 7, the junction terminal 28 is press-fitted into a holder 12 made of PBT. The holder 12 includes a joining terminal holding portion 12a for holding the joining terminal 28, and an upper fixing portion 12b for fixing the top surface of the joining terminal 28. The joining terminal 28 includes an inside of the holder 12. A bent portion 28a is formed which is held by the joint terminal holding portion 12a when being press-fitted into the connector. Further, in order to prevent the joining terminal from coming off from the holder, the widest length L1 dimension of the bent portion 28a is made longer than the distance L2 dimension between the joining terminal holding part 12a and the joining terminal holding part 12a. In addition, conductive silicon 30 is injected into the holder 12 into which the joining terminals 28 are press-fitted to ensure electrical continuity even after filling with the mold resin.

As a modification of the above-described embodiment, the terminal of the primary coil 16 and the terminal of the secondary coil 18, the igniter terminal 22a, the terminal to be a substantially flat metal terminal among the connector terminals 24a depends on the design matters. You may choose arbitrarily. The joining terminal 28 may be made of other materials such as brass, stainless steel, aluminum, phosphor bronze, etc., or may be subjected to surface treatment using tin plating or nickel plating. Further, the number and position of the groove portions 26 for preventing the fitting for fitting the terminals of the primary coil 16 and the terminals of the secondary coil 18, the igniter terminal 22a, and the joining terminal 28 formed on the connector terminal 24a. May be arbitrarily changed according to design matters. The holder 12 may be made of other materials such as modified PPE, nylon, PPS, PET, and elastomer. Further, the bent portion formed in the joining terminal 28 may be a protruding portion. Further, a conductive adhesive may be used as the resin injected into the holder 12a. In addition, the conductive silicon 30 is not necessarily required when the connection between the terminals is sufficiently made, and in this case, each terminal may be joined only by the joining terminal 28, The conductive silicon may be replaced with another easily conductive member having conductivity, such as epoxy, urethane, acrylic, thermoplastic resin, or the like.

Next, a method for manufacturing a joining terminal of an ignition coil will be described with reference to FIG. 6 showing a perspective view of a joining terminal after press working and FIG. 7 showing a perspective view of a joining terminal cut by a tie bar. In FIG. 6, the junction terminals 28 are formed by pressing one iron plate to the number necessary to connect the terminals of the primary coil 16 and the secondary coil 18, the igniter terminal 22a, and the connector terminal 24a. Has been. The joining terminal 28 is press-fitted into a holder 12 made of PBT and is held in the holder 12 by a bent portion 28a of the joining terminal 28. Further, in FIG. 7, conductive silicon 30 is injected into the holder 12, and then the tie bar is cut to separate the joining terminals.

10: Ignition coil
12: Holder
12a: Joint terminal holding part
12b: Upper fixed part
14: Case
15: Case fixing part
16: Primary coil
16a: primary bobbin
16b: Primary bobbin terminal
16c: Primary winding
18: Secondary coil
18a: Secondary bobbin
18b: Secondary winding
20: Iron core
20a: Core core
20b: Exterior iron core
22: Igniter
22a: Igniter terminal
24: Connector
24a: Connector terminal
26: Groove
28: Junction terminal
28a: Bending part
30: Conductive silicon

Claims (6)

A coil portion comprising a primary coil, a secondary coil and an iron core in the coil housing portion of the case;
An igniter for supplying a primary voltage and an ignition signal to the coil section;
Provided with a connector for connecting the igniter and an external battery,
In the ignition coil for an internal combustion engine in which the coil housing portion of the case is filled with mold resin,
Of the input terminal and the output terminal of the primary coil and the secondary coil, at least a terminal connected to the igniter terminal, the connector terminal, and the igniter terminal have a substantially flat metal terminal. ,
Each of the terminals has the same protruding direction,
The respective terminals are connected so as to realize electrical conduction between the respective terminals,
The ignition coil is characterized in that each of the terminals is connected by a junction terminal. 2. The ignition coil according to claim 1, wherein each of the terminals is formed with a groove for preventing disconnection for fitting the joining terminal in at least one place. 3. The ignition coil according to claim 1 or 2, wherein the joining terminal is press-fitted into a holder made of resin or the like. The ignition coil according to claim 3, wherein the holder has a junction terminal holding portion that holds the junction terminal;
The junction terminal is formed with a bent portion or the like that is held when pressed into the holder,
In order to prevent the joining terminal from coming off from the holder, the widest length L1 of the bent part is made longer than the distance L2 between the joining terminal holding part and the resistance holding part. coil. 5. The ignition coil according to claim 3, wherein conductive silicon or the like is injected into the holder into which the joining terminal is press-fitted to ensure electrical continuity even after filling with the mold resin. A coil portion comprising a primary coil, a secondary coil and an iron core in the coil housing portion of the case;
An igniter for supplying a primary voltage and an ignition signal to the coil section;
Provided with a connector for connecting the igniter and an external battery,
In the method of manufacturing an ignition coil for an internal combustion engine in which the coil housing portion of the case is filled with mold resin,
The number of the junction terminals necessary for connection of the respective terminals is formed by pressing from a single metal plate,
A method of manufacturing an ignition coil, wherein the joining terminals are separated by tie bar cutting after being press-fitted into the holder.

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