JPH0945558A - Ignition coil and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the effect of heat or vibration by arranging a primary coil on a coil bobbin formed by the extrusion molding of insulating material on the cable form magnetic core of ferromagnetic material, winding secondary coils between the flanges formed by the extrusion molding of the insulating material with expansion at certain distance and extrusion molding the insulating material on it. SOLUTION: A long cable form magnetic core 11 is formed by bundling the wire material 11a of electromagnetic soft iron. A primary coil bobbin 12 is formed by coating the magnetic core with the extrusion molding of fluororubber adding an enamel wire 13a along it lengthwise and a primary coil 13 is formed by winding the enamel wire 13a on it. A secondary coil bobbin 14, which is provided with flanges expanded in the direction of radius at certain distance, is formed by coating the primary coil bobbin 12 with the extrusion molding of the fluororubber and a secondary coil 15 are formed by sealing between the coils after winding enamel wire 15a on each section. An insulating layer 16 is formed on the secondary coil bobbin 14 covering it with fluororubber. This process provides an ignition coil, which requires a small installing space of a wire shape and is not affected by the heat or the vibration directly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition coil for an independent ignition system used in an internal combustion engine and a method for manufacturing the ignition coil.

[0002]

2. Description of the Related Art As shown in FIG. 12, an ignition coil of this type has a magnetic core 51 formed by laminating electromagnetic steel sheets, a primary coil bobbin 52 mounted on the magnetic core 51, and an enameled wire attached to the primary coil bobbin 52. A primary coil 53 formed by winding, a secondary coil bobbin 54 fitted on the outside of the primary coil bobbin 52 in which the primary coil 53 is formed, and an enamel wire wound around the secondary coil bobbin 54. Ignition coil body 50 having a secondary coil 55 formed by the above, and this ignition coil body 50
And a case 60 for accommodating the secondary coil 55 and a primary connector portion 61 having a connection terminal 62 to which the primary coil 53 is connected, and a connection to which the secondary coil 55 is connected. A secondary connector portion 63 having terminals 64 is formed.

A thermosetting resin such as an epoxy resin is filled in the space inside the case 60 in which the ignition coil body 50 is housed.
The secondary coil 53 and the secondary coil 55 are impregnated and fixed, and at the same time, the insulating property of withstanding the high output voltage of the secondary coil 55 is ensured.

In the ignition coil constructed as described above, the case 60 is directly fixed to the internal combustion engine with the secondary connector portion 63 fitted and inserted in the plug hole of the internal combustion engine.
The primary connector portion 61 is connected to a battery via a cable, and the secondary connector portion 63 is connected to a spark plug via a connecting component in the plug hole.

[0005]

By the way, as described above, in the ignition coil in which the primary coil bobbin 52 and the secondary coil bobbin 54 are assembled to the magnetic core 51 in which electromagnetic steel sheets are laminated, the ignition coil main body 50 itself is bulky. It is necessary to secure some installation space around the internal combustion engine to be installed.

Further, since such an ignition coil has a large number of constituent parts and the shapes of the respective parts are complicated, the cost for manufacturing a die for manufacturing these parts is high, and these parts are required for the ignition coil. Since it depends on the shape of the internal combustion engine in which it is installed, it is not versatile and different parts must be prepared according to the shape of the internal combustion engine.
This is a factor that increases the product cost of the ignition coil.

Further, as described above, such an ignition coil has a case 60 in which the ignition coil main body 50 is housed.
Since it is directly attached to the internal combustion engine, it is directly affected by heat and vibration from the internal combustion engine, which is a factor of shortening the life of the ignition coil.

Therefore, an object of the present invention is to provide an ignition coil which is not easily affected by heat and vibration from the internal combustion engine, and which can save space around the internal combustion engine and reduce the product cost, and a manufacturing method thereof. To do.

[0009]

In order to solve the above problems, the present invention has a flexible cable-shaped magnetic core formed by bundling wire rods made of a ferromagnetic material, and an insulating material extruded on the magnetic core. A primary coil winding bed formed by coating, a primary coil formed by winding an electric wire around the primary coil winding bed, and a primary coil winding bed on which the primary coil is formed A secondary coil winding bed formed by extruding an insulating material onto the secondary coil and having flange portions projecting in a radial direction at regular intervals, and each section partitioned by the flange portion of the secondary coil winding floor. Ignition coil provided with a secondary coil formed by winding an electric wire in multiple layers and an insulating layer formed by coating an insulating material on the secondary coil winding bed on which the secondary coil is formed. Provide Is shall.

Further, the ignition coil is made into a magnetic core by binding a plurality of wire rods formed by a continuously supplied ferromagnetic material, and a step of continuously feeding the magnetic core, and an outer periphery of the continuously fed magnetic core. A step of forming a primary coil winding bed on the continuous magnetic core by continuously extruding an insulating organic material on the surface, and winding a wire on the primary coil winding bed to form a primary coil. By continuously extruding an insulating organic material onto the primary coil-rolled bed on which the primary coil is formed by extrusion coating, a secondary coil-rolled bed having a flange portion protruding in a radial direction at regular intervals is obtained. And a step of forming and winding the wire in multiple layers in a line around each section partitioned by the collar portion of the secondary coil winding bed.
A step of forming a secondary coil, a step of forming an insulating layer by coating an insulating organic material on the secondary coil winding bed having the secondary coil formed therein, and the magnetic core continuously supplied at a predetermined position. It is manufactured by a manufacturing method of an ignition coil including a step of cutting.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1 (a), this ignition coil 10 includes a cable-shaped magnetic core 11 having a predetermined length, which is a ferromagnetic body, and a primary coil winding formed from one end to the other end of the magnetic core 11. A floor 12, a primary coil 13 formed by winding an enamel wire 13a around the primary coil winding bed 12, and an entire area of the primary coil winding bed 12 on which the primary coil 13 is formed. Secondary coil winding floor 14 formed over the entire length, and the secondary coil winding floor 14
A secondary coil 15 formed by winding an enamel wire 15a around the wire and sealing the space between the wires with an insulator;
An insulating layer 16 formed over the entire area of the secondary coil winding bed 14 on which the secondary coil 15 is formed, an iron foil 17 wound around the outer periphery of the insulating layer 16, and an iron foil 17
And a sheath 18 for covering.

The magnetic core 11 is an electromagnetic soft iron rod (JIS C
2503-90 SUYB1) is φ0.
It is a bundle of several to several tens of wire rods 11a drawn to have a thickness of 3 to 1.0 mm and has a certain degree of flexibility, and thus can be freely bent. In this embodiment, a plurality of wire rods 11a are simply bundled, but for example, a plurality of wire rods 11a are bundled and twisted, or after a plurality of wire rods 11a are bundled and twisted. Alternatively, the magnetic core 11 may be formed by compressing in the radial direction.

The primary coil winding bed 12 has the magnetic core 11
It is formed by extrusion-coating an insulating organic material with a thickness of 0.3 to 2.0 mm. Inside the primary coil winding bed 12, an enamel wire with a diameter of 0.4 to 0.6 mm is used as a magnetic core. A vertically extending wire 13b is formed by vertically extending along the longitudinal direction of 11 and one end of which is electrically connected to the primary coil 13 by welding or the like. As the insulating organic material, it is possible to extrude plastic materials such as fluororubber, ethylene / propylene rubber (EPDM, EPM), silicone rubber, and cross-linked polyethylene, and the heat resistant temperature is appropriately high, A material that has a proven record as an insulating material and is flexible is suitable.

The secondary coil winding bed 14 has an insulating organic material similar to that of the primary coil winding bed 12 having a thickness of 0.
It is formed by covering with 50 to 3.00 mm, and this secondary coil winding bed 14 has a flange portion 14a protruding in the radial direction at regular intervals.

As the insulating organic material forming the secondary coil winding bed 14, it is important that it has heat resistance since Joule heat generation from the primary coil 13 is large. On the other hand, as the insulating organic material forming the insulating layer 16, although the heat generated from the secondary coil is small, since it is installed in the vicinity of the internal combustion engine, the ambient temperature is high and heat resistance of about 120 ° C. is also required. Become. The electrical characteristics required for the insulating organic material forming the secondary coil winding bed 14 and the insulating layer 16 are a specific resistance of 10 ¹² Ω · cm.
As described above, the withstand voltage is required to be 20 KV / mm or more, and it is also an important condition to have a certain flexibility like the primary coil winding floor 12.

The winding of the primary coil 13 and the vertically extending wire 1
The enamel wire 13a, which is 3b, has a diameter of 0.4 to 0.
The diameter of the enamel wire 15a, which is the winding of the secondary coil 15, is 0.03 to 0.1 mm.
I'm using one. The primary coil 13 simply winds the enamel wire 13a horizontally on the primary coil winding bed 12, but the secondary coil 15 is shown in FIG.
As shown in (b), the collar portion 1 of the secondary coil winding floor 14
For each section partitioned by 4a, the enamel wire 13a is stacked in multiple layers in the direction shown by the arrow in the figure and wound, so-called aligned section winding, and between the wires, for example, silicone oil, flexible epoxy, etc. Since the winding number of the secondary side is larger than that of the primary coil 13, which is simply wound in a horizontal direction, the winding number ratio of the secondary side to the primary side is wide. It has the advantage that it can be changed to

Further, as described above, since one end of the winding of the primary coil 13 and one end of the vertical wire 13b are connected to each other, the other end of the winding to be the lead wire of the primary coil 13 is connected to the other end. There is an advantage that the vertical wire 13b can be drawn out from the same end.

The insulating layer 16 is the primary coil winding floor 1
The sheath 1 is formed by extrusion coating an insulating organic material similar to that of No. 2 with a thickness of about 1 to 4 mm.
As the material of No. 8, silicone rubber, ethylene / propylene rubber (EPDM, EPM), acrylic rubber and the like are suitable.

The ignition coil 10 is covered with the iron foil 17 as described above. The reason why the iron foil 17 is provided is that the coil has a shielding function because it is a noise generation source, and therefore the energization is performed. This is because the magnetic field generated by the magnetic field is adjusted, the withstand voltage with respect to the outside is improved, and the electrostatic capacity is increased by grounding the shield to increase the ignition energy. In addition to the iron foil 17, a ferromagnetic material such as nickel, cobalt, or an amorphous alloy may be coated.

Ignition coil 10 constructed as described above
Is manufactured as follows. First, in the first step, since a plurality of wire rods 11a obtained by drawing the electromagnetic soft iron rod by a wire drawing machine (not shown) are continuously supplied,
As shown in FIG.
Are bundled together and sent as a continuous flexible cable-shaped magnetic core 11 to the next step.

In the second step, one enameled wire 13a is vertically aligned on the magnetic core 11 thus continuously fed out as shown in FIG. Meanwhile, an insulating organic material such as fluororubber is continuously extrusion-coated by the first organic material extrusion device 32 to form the primary coil winding bed 12, and is sent to the next step.

In the third step, the enamel wire 13a is formed on the primary coil winding bed 12 formed on the magnetic core 11 thus continuous by the primary coil winding device 33 as shown in FIG. By horizontally winding, the primary coil 13 is formed on each primary coil winding bed 12 and sent to the next step.

In the fourth step, as shown in FIG. 5, on the respective primary coil winding beds 12 on which the primary coils 13 are formed in this way, a fluororubber or the like is produced by the second organic material extruding device 34. The insulative organic material is continuously extrusion-coated to form the secondary coil winding bed 14 having a plurality of flange portions 14a radially extending at regular intervals, and the secondary coil winding bed 14 is sent to the next step.

As shown in FIG. 6, the second organic material extruding device 34 includes a plurality of circumferential grooves 3 for forming the collar portion 14a.
The molds 34a of the mold group 34a are rotated while rotating two sets of mold groups 34a, which are endlessly connected half molds 34b provided with 4c at regular intervals, in the supply direction of the magnetic core 11.
The magnetic core 11 on which the primary coil 13 is formed is sandwiched by b, and the insulating organic material is extruded into the mold 34b by the screw 34d.
The secondary coil winding bed 14 having 4a is formed by extrusion. Other molding methods include injection molding, blow molding, vacuum molding and the like.

In the fifth step, as shown in FIG. 7, each section of the secondary coil winding floor 14 thus formed which is partitioned by the flange portion 14a is treated by the secondary coil winding device 35 as described above. By winding the enamel wire 15a in an aligned section and further sealing the space between the wires with silicone oil or the like, the secondary coil 15 is formed on the secondary coil winding bed 14 and sent to the next step.

In the sixth step, as shown in FIG. 8, fluororubber or the like is applied to each of the secondary coil winding beds 14 thus formed with the secondary coil 15 by the third organic material extrusion device 36. The insulating organic material is continuously extrusion-coated to form the insulating layer 16, and the insulating layer 16 is sent to the next step.

In the seventh step, as shown in FIG. 9, the iron foil winding device 37 winds the iron foil 17 on the insulating layer 16, and then the fourth organic material extrusion device 38 winds the iron foil 17 on the iron foil 17. An insulating organic material such as silicone rubber is continuously extrusion-coated to form a sheath 18, which is then sent to the next step.

In the final eighth step, as shown in FIG. 10, a cutting device 39 cuts the wire into a predetermined length, and one end of the winding of the primary coil 13 and one end of the vertical splicing wire 13b are pulled out. By welding each other, the cable-shaped ignition coil 10 having a predetermined length is sequentially manufactured.

In this embodiment, the insulating layer 16 is formed by extrusion coating an insulating organic material such as fluororubber.
However, the present invention is not limited to this, for example, covering a tube formed of an insulating material, winding an insulating tape, applying a liquid resin, or molding with an insulating resin. It can also be formed by

Further, in this embodiment, the insulating layer 16 is used.
A magnetic shield layer made of a ferromagnetic material such as an iron foil 17 is provided on the outside of, but such a magnetic shield layer is not necessarily provided.

Further, in the above manufacturing method, the magnetic cores 11, 1
Secondary coil winding floor 12, primary coil 13, secondary coil winding floor 1
4, the secondary coil 15, the insulating layer 16 and the like are formed in a series of steps. For example, the primary coil side 12 in which the primary coil winding 12 and the primary coil 13 are sequentially formed on the continuously supplied magnetic core 11 An element and a secondary coil side element in which a continuous tubular secondary coil winding floor 14 having a collar portion 14b is formed, and then a secondary coil 15, an insulating layer 16 and the like are sequentially formed on the secondary coil winding floor 14. It is also possible to manufacture the ignition coil 10 by separately manufacturing and, and then assembling the secondary coil side element to the primary coil side element. In this case, the gap between the primary coil side element and the secondary coil side element must be filled with an insulating organic material.

Ignition coil 10 manufactured in this way
Is a flexible cable and can be handled in the same manner as a normal high tension cord, and is specifically used as follows.

As shown in FIG. 11, one end of a connector 24 housed in the plug hole 21 is connected to the terminal 23 of the spark plug 22 installed in the plug hole 21 of the internal combustion engine 20. Connector 2
The other end side of 4 is supported by a fixing member 25 fixed to the internal combustion engine 20, and the ignition coil 10 has the secondary coil 15 at one end side thereof and the connection connector 2
4 is connected to the other end side of the
Next coil 13 is power transistor 26, igniter 2
7. Connected to a control circuit such as an electronic control unit (ECU) 28.

As described above, since the ignition coil 10 is in the form of a flexible cable, the installation space for the ignition coil 10 is smaller than that of the conventional one, and it is not necessary to directly mount it on the internal combustion engine 20 as described above. Since it is not necessary to change the shape, structure, etc. of the ignition coil according to the shape of the internal combustion engine 20, versatility is enhanced.

Further, since the ignition coil 10 is formed in the form of a cable to increase the distance from the internal combustion engine 20, it is less susceptible to heat and vibration from the internal combustion engine 20, and the life of the ignition coil 10 itself is extended. Since it is not necessary to make the insulating layer 16 and the sheath 18 surrounding the secondary coil 13 thicker than necessary, the capacitance increases, and the ignition energy increases accordingly.

Further, since the primary coil bobbin 12 and the secondary coil bobbin 14 corresponding to the conventional primary coil bobbin and secondary coil bobbin are respectively formed by extrusion coating of an insulating organic material, the number of parts is small. Moreover, since the use of the mold is reduced, the cost of the product can be reduced by reducing the cost of the mold.

Further, in the above-mentioned manufacturing method, since extrusion molding is frequently used, it is possible to use the extrusion coating device used for manufacturing the coated electric wire, and it is possible to reduce the equipment cost.

[0038]

As described above, the entire ignition coil of the present invention is formed in the same linear shape as that of a normal cable, so that the installation space can be reduced.
Moreover, since it does not need to be directly attached to the internal combustion engine, it is not affected by the shape of the internal combustion engine, the versatility is increased, and heat and vibration from the internal combustion engine are not directly received.
This has the effect of extending the product life.

Further, since the number of constituent parts is small and the primary coil winding floor and the secondary coil winding floor are respectively formed by extrusion coating with an insulating material, the use of a mold is reduced when manufacturing the components, The product cost can be reduced by reducing the die cost.

Further, in this ignition coil, the secondary coil is formed by winding the electric wire in an aligned section around each section partitioned by the collar portion of the secondary coil winding bed having a collar portion protruding in the radial direction at regular intervals. Because it was formed
Since the flexibility of the number of turns of the secondary side is increased as compared with the secondary coil in which the electric wire is simply wound horizontally, there is also an effect that the number of turns of the secondary side with respect to the primary side can be widely changed.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a process chart showing a manufacturing method of the same.

FIG. 3 is a process drawing showing the manufacturing method of the above.

FIG. 4 is a process drawing showing the manufacturing method of the above.

FIG. 5 is a process drawing showing the manufacturing method of the above.

FIG. 6 is a schematic view showing a second organic material extrusion apparatus of the above.

FIG. 7 is a process drawing showing the manufacturing method of the above.

FIG. 8 is a process drawing showing the manufacturing method of the above.

FIG. 9 is a process drawing showing the manufacturing method of the above.

FIG. 10 is a process drawing showing the manufacturing method of the above.

FIG. 11 is a schematic view showing an example of use of the above.

FIG. 12 is a sectional view showing a conventional example.

[Explanation of symbols]

 10 Ignition coil 11 Magnetic core 12 Primary coil winding bed 13 Primary coil 13b Vertical laying wire 14 Secondary coil winding bed 14a Collar portion 15 Secondary coil 16 Insulating layer 17 Iron foil 18 Sheath 31 Bundling device 32 First organic material extrusion device 33 primary coil winding device 34 second organic material extrusion device 35 secondary coil winding device 36 third organic material extrusion device 37 iron foil winding device 38 fourth organic material extrusion device 39 cutting device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location 9375-5E H01F 31/00 501Q

Claims (2)

[Claims] 1. A flexible cable-shaped magnetic core formed by bundling wire rods made of a ferromagnetic material, a primary coil winding bed formed by extruding an insulating material on the magnetic core, and 1. A primary coil formed by winding an electric wire around a secondary coil winding bed, and a primary coil formed on the primary coil winding bed on which the primary coil is formed by extrusion coating an insulating material at regular intervals. A secondary coil winding bed having a flange portion projecting in a radial direction; and a secondary coil formed by aligning and winding an electric wire in multiple layers on each section partitioned by the flange portion of the secondary coil winding floor, An ignition coil, comprising: an insulating layer formed by coating an insulating material on the secondary coil winding bed on which the secondary coil is formed. 2. A step of forming a magnetic core by bundling a plurality of wire rods formed by a continuously supplied ferromagnetic material, continuously feeding the magnetic core, and an insulating organic material on the outer peripheral surface of the magnetic core continuously fed. A step of forming a primary coil winding bed on the continuous magnetic core by continuously extrusion-coating a material; a step of winding an electric wire on the primary coil winding bed to form a primary coil; A step of forming a secondary coil winding bed having a flange portion protruding in a radial direction at regular intervals by continuously extrusion-coating an insulating organic material on the primary coil winding bed on which the secondary coil is formed; Forming a secondary coil by winding an electric wire in multiple layers around each section partitioned by the collar portion of the secondary coil winding bed; and on the secondary coil winding bed having the secondary coil formed thereon. Insulating organic material Process and method for producing an ignition coil and a step of cutting the core which is continuously supplied at a predetermined position for forming an insulating layer by coating a.