JPS60718A - Ignition coil - Google Patents

Abstract

PURPOSE:To contrive miniaturization and lightweightedness of the title ignition coil by a method wherein a secondary coil is formed by fitting an insulating plate, whereon a thin film conductor of spiral pattern will be formed, on a secondary spool. CONSTITUTION:A primary coil 3 is provided on the primary spool 2 located on the circumference of a core 1, and a secondary spool 4 is provided thereon. A secondary coil 10, consisting of a plurality of the first and second insulating plates 7 and 8 in fitted state, is provided on the secondary spool 4. A thin film conductor 7a of spiral pattern to be wound in clockwise direction is formed on one surface of the first insulated plate 7, and a thin film conductor 8a of spiral pattern to be wound in counter-clockwise direction is formed on other surface of the second insulated plate 8. Then, an electrode 11 is provided at the pattern starting point of thin film conductors 7a and 8a, and they are electrically connected successively. As a result, the small-sized and lightweighted ignition coil having almost no disconnection of wire can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ignition coil used as an ignition device for an internal combustion engine.

Conventionally, in this type of ignition coil, as shown in FIG. A secondary coil 5 similarly made of a plurality of layers is coaxially disposed on a secondary winding frame 4 provided on the secondary winding frame 4 with an insulating paper 5c between the eyebrows interposed therebetween. These are integrated in a molded part 6 made of synthetic resin or the like to form an ignition coil. It is connected to the. In the figure, 3a and 5b indicate the winding start lead part of the primary coil 3 and the winding end cleat part of the secondary coil 5, respectively.

In this ignition coil, the iron core 1 forms a common magnetic path for both coils 3 and 5, and when the second coil 3 is energized, the iron core 1
Since magnetic energy is stored in the secondary coil 5, when the energization is interrupted, a high voltage for ignition is generated in the secondary coil 5.

Now, the above-mentioned secondary coil 3 has a diameter of 0.5 to 1, and Q
The secondary coil 5 has a diameter of 60 to 80μ.
n is used, and as the insulating paper 5c, 10 to 30
μ-thickness is often used.

Since the number of turns of the secondary coil 5 is 10,000 tan or more, the number of layers is very large. Therefore, it is necessary to perform interlayer insulation using the insulating paper 5C.

However, in order to form such a secondary coil 5, the amount of winding is extremely large, so there is a risk of wire breakage during winding, and it is necessary to insert insulating paper 5c each time each layer is formed. Moreover, there is a limit to the automation of manufacturing, and furthermore, there are limits to miniaturization due to the structure.

The present invention was made in order to eliminate the above-mentioned conventional drawbacks, and aims to provide a small, lightweight ignition coil that is almost never disconnected, does not require insulating paper, and can be automated. shall be.

An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the ignition coil according to the present invention has a primary coil 3 coaxially disposed in multiple layers on a primary winding frame 2 on the peripheral surface of an iron core 1, and a secondary winding frame 4 on top of this. It is provided.

A secondary coil 10 is disposed on the secondary winding frame 4 and is made up of a large number of first and second insulating plates 7 and 8 fitted together. 1st
As shown in FIG. 3, a thin film conductor 7a having a spiral pattern wound clockwise is formed on one surface of the insulating plate 7, and a hole 7b for fitting the secondary winding frame 4 is provided in the center. ing. Further, on one surface of the second insulating plate 8, a thin film conductor 8a having a spiral pattern wound counterclockwise is formed, and a fitting hole 8b is similarly provided. These thin film conductors 7a and 8a can be automatically formed on an insulating plate by a known high-precision pattern forming method such as a printing method, a vapor deposition method, or an etching method. It can be formed by Further, the insulating plates 7 and 8 can be formed from extremely thin plates of ceramic or plastic.

Electrodes 11 are provided at the pattern start points (inside) of the thin film conductors 7a and 8a, and other electrodes 12 are provided at the pattern end points, respectively.

Such first and second insulating plates 7 and 8 are shown in FIG.
As shown in a), the secondary winding frame 4 is fitted closely along the axial direction of the secondary winding frame 4 with the surface having thin film-conductors 7a and 8a alternately facing leftward in the figure. As shown in FIGS. 3 and 4, the electrode 12 on the outer circumferential side of the first insulating plate 7 and the electrode 12 on the outer circumferential side of the second insulating plate 8,
The electrode 11 on the inner circumferential side of the insulating plate 7 and the electrode 11 on the inner circumferential side of the second insulating plate 8 are electrically connected along the alignment direction by eleventh welding or other means. Therefore,
These first and second insulating plates 7.8 are arranged alternately.
The thin film conductors 7a and 8a are electrically connected in series. The electrode 11 on the inner peripheral side of the first insulating plate 7 located on one end side is connected to the winding end series part 3b of the primary coil 3 via the lead wire 9, and the second electrode 11 located on the other end side
A lead wire 14 is connected to the electrode 12 on the outer circumferential side of the insulating plate 8, and this lead wire 14 is connected to the winding start lead portion 3a and the winding end lead portion 3b of the -th coil 3, as shown in FIG.
It is also pulled out from the mold part 6.

Incidentally, it is preferable that the first and second insulating plates 7 and 8 be fixed to each other by filling an insulating adhesive between them.

Furthermore, the electrodes 1j and 12 of the insulating plates 7 and 8 can be connected in series with respective lead wires.

As explained above, according to the present invention, a spiral thin film conductor is formed on one side of a thin insulating plate, and these insulating plates are arranged so as not to hinder the generation of induced voltage. By electrically connecting thin film conductors in series, a secondary coil can be created without winding wire or using insulating paper as in the past. Therefore, it is possible to provide a high-quality, inexpensive ignition coil that has almost no risk of disconnection, is small in size, generates heat, and can be mass-produced by automation.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are a cross-sectional view and a front view showing a conventional ignition coil, and FIGS. 2(a) and (b) are a cross-sectional view and a front view showing an ignition coil according to an embodiment of the present invention. 3 is a perspective view showing separated insulating plates constituting the secondary coil according to the present invention, and FIG. 4 is a sectional view showing the connection of thin film conductors between the insulating plates of FIG. 3. DESCRIPTION OF SYMBOLS 1... Iron core, 3... Secondary coil, 4... Secondary winding frame, 5°10... Secondary coil, 7, 8... First and second insulating plates, 7a, 8a...Thin film conductor, 11.12
···electrode. In the drawings, the same reference numerals indicate the same or corresponding parts. Agent Masuo Oiwa

Claims (1)

[Claims] It includes an iron core, a primary coil wound on the iron core in multiple layers through a primary winding frame, and a secondary coil coaxially arranged on the secondary coil through a secondary winding frame. An ignition coil, wherein the secondary coil has a first coil formed with a thin film conductor wound clockwise in a spiral pattern on one side.
and a second insulating plate having a spiral pattern of thin film conductors wound counterclockwise on one side thereof, the thin film conductors are alternately arranged on the secondary winding frame along its axial direction. An ignition coil characterized in that the thin film conductors of each adjacent insulating plate are electrically connected in series.