JPS595952Y2 - ignition coil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an ignition coil used in an ignition system for an internal combustion engine, and in particular to an improvement in the connection between the end of the secondary winding of the ignition coil and the high-voltage cord.

The secondary winding of the above ignition coil is generally 0.05 to 0.0.
We use ultra-fine enamel coated wire of about 0.07 mm,
In order to draw out the end of the winding to the outside, conventionally a thick metal plate in the shape of a letter is fixed to the outer periphery of the coil with taping, and this metal plate is attached to the end of the winding of the secondary winding and the high voltage for external extraction. I had soldered the side cord.

However, in such a conventional leader line connection structure,
Not only does the number of parts and man-hours required for coil assembly increase, but due to the thickness of the metal plate, a step is created between the end of the winding soldered to the upper surface of the metal plate and the outer periphery of the coil.

For this reason, the end of the winding is likely to break near the metal plate, and the stepped portions are not satisfactorily filled with impregnating agent, resulting in voids, which tend to cause dielectric breakdown due to corona generation.

In view of these shortcomings, the present invention has developed a winding end of the secondary winding,
The present invention provides an ignition coil with an improved structure at the connection part to the high voltage side cord.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In Fig. 1, 1 is an iron core, 2 is a bobbin fitted to this iron core, 3 is a primary winding wound around the bobbin 2, and 4 is a secondary winding wound on the primary winding 3. It is a winding.

Reference numerals 5a and 5b are both made of insulating material and form a side plate for forming the collar of the bobbin 2. Reference numeral 6 is a primary wire whose tip end is fixed to one side plate 5a, and one end of the primary winding 3 is connected to this primary wire. is soldered.

7 is a kraft paper wound on the secondary winding 4 as an exterior material, 8 is a connection terminal made of copper foil to which the end of the secondary winding is connected, and 9 is connected to this terminal. This is the high voltage side cord.

This code 9 connects a part of the outer peripheral side of the other side plate 5b,
It is held tightly in a groove of a holding portion 5C which is provided to protrude in the radial direction.

Reference numeral 10 denotes an insulating molding material molded onto the iron core 1 so as to cover the side plates 5a, 5b, the ends of the primary wire 6, the craft paper 7, the terminals 8, the ends of the cord 9, etc. .

Next, the detailed structure of the connection terminal 8 will be explained with reference to FIGS. 2 and 3.

In these drawings, the same parts as in FIG. 1 are designated by the same reference numerals.

The outer periphery of the secondary winding 4 is wrapped with an insulating sheathing material and 1.5 turns of kraft paper 7 is wrapped around it. At the overlapping part, solder is applied in advance to the approximate center of a copper foil having a predetermined length and width. A connecting terminal 8 in which a convex portion 8a is formed by applying a heaping up of bonding agent is inserted, and the terminal end 4a of 40 turns of the secondary winding is soldered to one end of the terminal 8.

Then, the protrusion 8a is made to protrude from a through hole 7a that is previously provided at a portion where the kraft paper 7 contacts the protrusion 8a.

A high voltage side cord 9 is connected to this convex portion 8a as shown in FIG.

The end of the roll of kraft paper 7 is sealed with adhesive tape 11.

In this embodiment, the connection terminal is made of copper foil, but it is not limited to copper foil, and may be made of metal conductor foil.

In the ignition coil of the present invention, the connection terminal between the winding end of the secondary winding and the high-voltage side cord is made of metal conductor and is wrapped between the layers of the exterior material. There is no difference in level between the installation parts.

Therefore, no unreasonable force is applied to the connection end of the thin wire-wound conductor connected to the terminal, and disconnection accidents at this portion can be prevented.

In addition, there is no need to create extra voids due to differences in level.
Dielectric breakdown due to corona generation is also prevented.

Furthermore, the above-mentioned connection terminal has the advantage that the protrusion provided on the surface of the metal conductor foil protrudes from the through hole provided in the exterior material and is wrapped between the layers of the exterior material, making it extremely easy to position and fix the terminal. There is.

Furthermore, since a metal conductor foil is used, unlike conventional metal plate terminals, there is no risk of the ends of the metal fittings damaging the coil or exterior material.

[Brief explanation of the drawing]

FIG. 1 is a partial longitudinal sectional front view of an ignition coil according to the present invention, and FIGS. 2 and 3 are explanatory diagrams showing how connection terminals are arranged in the ignition coil according to the present invention. 1... Iron core, 3... Primary winding, 4...
...Secondary winding, 4a... End of winding of secondary winding, 7... Kraft paper as exterior material, 7a.
...Through hole, 8...Connection terminal, 8a...
...Protrusion, 9...High voltage side cord.

Claims (1)

[Scope of utility model registration request] In an ignition coil formed by winding a primary winding and a secondary winding around an iron core and connecting a high voltage side cord to a winding end of the secondary winding, the winding end of the secondary winding and the high voltage side cord are connected to each other. The connection terminal for connecting is made of a metal conductor foil with a convex part made of a bonding agent formed on a part of the surface, and is wound between the layers of the exterior material wound on the secondary winding. The convex portion protrudes from a through hole provided in the exterior material, one end of the high voltage side cord is connected to the protruding portion, and the winding end of the secondary winding is connected to one end of the metal conductor foil. An ignition coil characterized in that it is connected to.