JPS6012261Y2 - Molded internal combustion engine ignition system - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a molded internal combustion engine ignition device in which an ignition coil and a printed circuit board on which parts constituting an internal combustion engine ignition circuit are attached together with the ignition coil are molded with resin. .

Since ignition devices for internal combustion engines are required to be weather resistant, their main parts are molded with resin.

In this type of ignition device, a hole is provided in the printed circuit board on which the circuit components constituting the ignition circuit are mounted, and the iron core of the ignition coil is fitted into this hole, and the printed circuit board is brought into contact with a step provided on the iron core. There is one in which the primary and secondary coils of the ignition coil and a printed circuit board are arranged in the longitudinal direction of the iron core and molded with resin.

However, since such a structure uses a specially shaped iron core with a stepped portion, the iron core cannot be used in common with ignition coils used in other types of ignition devices, which has the disadvantage of increasing costs.

In addition, cores made of laminated steel plates formed by punching, which cannot be processed with high precision, have poor dimensional accuracy. Unavoidable looseness between the printed circuit board and the hole could result in the printed circuit board being tilted without being reliably positioned.

In addition, in conventional ignition devices of this type, in order to achieve insulation between the primary and secondary coils of the ignition coil and the printed circuit board,
The insulation distance between the primary and secondary coils and the printed circuit board was secured by extending a part of the ignition coil's bobbin toward the printed circuit board and bringing the extended part into contact with the printed circuit board. This structure has the disadvantage that the distance between the coil and the printed circuit board becomes long, resulting in an increase in the size of the device.

The purpose of the present invention is to ensure the positioning of the printed circuit board, and to shorten the distance between the primary and secondary coils of the ignition coil and the printed circuit board of the control unit, thereby achieving miniaturization. An object of the present invention is to provide a molded internal combustion engine ignition device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The molded internal combustion engine ignition device of the present invention will be explained in detail below with reference to the illustrated embodiments.

FIG. 1 is a cross-sectional view of one embodiment of the present invention, in which 1 is an ignition coil, and 2 is an ignition coil arranged on the side of the primary and secondary coils 100 of 1 of the ignition coil. A control unit 3, which also constitutes an internal combustion engine ignition circuit, is an insulating member disposed between the coil 100 and the control unit 2.

Further, 4 connects the non-grounded end of the secondary coil and the spark plug in order to apply the high voltage induced in the secondary coil of the ignition coil 1 to the spark plug attached to the cylinder of the internal combustion engine (not shown). It is a high voltage cord.

Reference numeral 5 denotes a case made of metal or resin that houses the ignition coil 1, the control unit 2, and the insulating member 3. The case 5 is filled with thermosetting insulating resin 6 to protect the ignition coil 1 to the insulating member 3. Each part is molded.

The ignition coil 1 includes a primary coil 10 as shown in FIG.
1 and a secondary coil 102 shown in FIG.

The primary coil 101 is wound around an I-shaped laminated core 103 at a position offset to one end from the center, and insulating side plates 104, 104 fitted to the core 103 are connected to the primary coil 101.
is in contact with both end faces of.

The primary coil 101 can also be wound around a flanged bobbin attached to the iron core 103, in which case the flanges of the bobbin correspond to the side plates 104, 104 described above.

Attachment holes 105, 105 are provided near both ends of the iron core 103, passing through the core in the lamination direction, and a ground terminal fitting 106 is provided on the end surface of the portion of the iron core 103 that protrudes longer from the primary coil 101 in the lamination direction. is fixed with rivets etc.

Note that 101a and 101b are lead wires at the winding start end and winding end of the primary coil 101, respectively.

The secondary coil 102 shown in FIG. 3 is wound around a cylindrical bobbin 107 having an inner diameter that allows the primary coil 101 to pass through, and a lead-shaped terminal fitting is attached to the inner peripheral surface of one end in the axial direction of the bobbin 107. 108 is fixed with eyelets, rivets, etc., and the winding start (ground side end) of the secondary coil 102 is connected to this terminal fitting 108.

The primary coil 101 is inserted inside the bobbin 107 of the secondary coil 102 to form the ignition coil 1.

When the ignition coil 1 is constructed by combining the primary and secondary coils in this way, the ground terminal fitting 106 connected to the iron core 103 is exactly aligned with the terminal fitting 108 of the secondary coil 102, and the tips of both terminal fittings are aligned. The positions are now aligned.

The control unit 2 has a control circuit attached to a printed circuit board that suddenly changes the current in the primary coil 101 of the ignition coil 1 at the ignition position of the engine to induce a high voltage in the secondary coil 102. A circuit component whose circuit includes a capacitor provided on the primary side of the ignition coil, a diode that rectifies the output of an exciter coil (not shown) and applies it to the capacitor, and a thyristor that discharges the charge of the capacitor to the primary coil 101. The control unit 2 and the ignition coil 1 constitute a capacitor discharge type internal combustion engine ignition circuit.

The external appearance of the control unit 2 is as shown in FIG. 4, in which 201 is a printed circuit board having an approximately oval shape, and circuit components such as a capacitor C1 and a thyristor SCR are attached to one surface of the printed circuit board 201. There is.

A substantially rectangular window portion 20 is provided in the substantially central portion of the printed circuit board 201.
2 is formed, and a U-shaped notch 203 is formed on one side of the rectangle of the window portion 202.

Further, the capacitor C is arranged at one end of the printed circuit board 201 so as to protrude from the board at a substantially right angle, and at the corner of the end of the printed circuit board 201 where the capacitor C is arranged, a high voltage A notch (relief portion) 204 is formed for passing the cord holding portion.

Further, a pair of holes 205 and 205' are formed near the end of the printed circuit board opposite to the capacitor C.

5 to 7 show the structure of the insulating member 3,
This insulating member is the primary and secondary coil 1 of the ignition coil 1.
Coil 10 is interposed between 00 and printed circuit board 201.
0 and the printed circuit board 201.
An iron core through hole 302 through which the iron core 103 passes is formed at a position slightly shifted toward one end side from the center of this plate-shaped portion 301.

A substantially duct-shaped core fitting portion 303 into which the core 103 is fitted is formed integrally with the plate portion 301 by protruding the peripheral edge of the core through hole 302 in a direction perpendicular to the plate surface of the plate portion 301. , protrusions 304° 304 for abutting the printed circuit board 201 are provided on opposing sides of the core fitting portion 303.
is provided.

A part of one side surface perpendicular to each side surface on which the protrusions 304, 304 of the iron core fitting part 303 are provided is cut out to have approximately the same width dimension as the notch part 203 provided in the printed circuit board 201. A ground terminal insertion groove 305 is formed in the plate portion 301, and this insertion groove 305 and the core through hole 30 are formed in the plate-like portion 301.
A U-shaped notch 306 is formed which is continuous with the two.

The window portion 202 of the printed circuit board 2 is formed so as to fit the duct-shaped core fitting portion 303 of the insulating member without any gap. When the parts 303 are fitted together, the notch 305 of the insulating member 3 is aligned with the notch 203 of the printed circuit board.

Near the end of the plate-like part 301 of the insulating member 3 on the side closer to the core fitting part 303, there is a 1 that protrudes on the same side as the core fitting part 303 and fits into the holes 205, 205 of the printed circuit board 2, respectively.
A pair of columnar protrusions 307 and 307' are formed, and through holes 309a and 309b are formed at the axial center of these protrusions, through which the lead wires 101a and 101b of the primary coil 101 are inserted, respectively.

A bottomed cylindrical high voltage cord holding part 310 is provided integrally with the insulating plate at a corner of the plate part 301 on the end side away from the core fitting part 303.

This high-voltage cord holding part 310 is provided so as to extend in a direction perpendicular to the plate-like part 301 and open in the direction in which the core fitting part 303 protrudes. A terminal fitting 311 to which the high voltage cord 4 is connected is fixedly provided.

A protrusion 312 that protrudes to the same side as the core fitting part 303 is provided at the corner of the plate-shaped part 301 on the opposite side from the high voltage cord holding part 310.
is integrally provided, and this protruding portion 312 has a core fitting portion 3.
The base of a tongue-shaped terminal fitting 313 that protrudes to the same side as 03 is buried.

An output terminal fitting of an exciter coil (not shown) is connected to this terminal fitting 313.

A core fitting portion 303 is located at the end of the plate portion 301 between the high voltage cord holding portion 310 and the terminal fitting 313.
On the opposite side, a capacitor holding part 315 is provided integrally with the plate part 301 and protrudes perpendicularly to the plate part 301.

This capacitor holding part 315 has a flat plate part 316 that supports one main surface of the capacitor C attached to the printed circuit board 201.
and side wall portions 317 and 317 having a substantially crescent-shaped cross-sectional shape rising from both ends of the flat plate portion 316 in the width direction, and an end wall rising from the end of the flat plate portion 316 remote from the plate-like portion 301. It consists of 318.

The spacing between the side walls 317 and 317 of the capacitor holding part 315 is set to be slightly smaller than the width of the capacitor C, so that when the capacitor C is inserted between the side walls 317 and 317, the elasticity of the both walls allows the capacitor to C is now being held.

The insulating member 3 is placed in the case 5 around the plate-shaped portion 301.
When inserted into the case 5, the insulating member 3 comes into contact with the inner surface of the case 5.
An appropriate number of positioning protrusions 319 (four in the illustrated example) are provided for positioning.

To assemble the ignition device of this embodiment, first, as shown in FIG. At the same time, the lead wires 1°la and 101b of the primary coil 101 are inserted into the protrusions 307 and 303.
07' through holes 309a and 309b, respectively.

In this state, the core 103 is inserted into the core fitting portion 303 until the side plate 104 of the primary coil comes into contact with the plate-like portion 301 of the insulating member 3.
Push it into.

Next, the secondary coil 102 is fitted onto the outer periphery of the primary coil 101, and one end surface of the secondary coil 102 is brought into contact with the plate-shaped portion 301 of the insulating member.

In this case, the terminal fitting 108 of the secondary coil 102 is
Notch 306 along with ground terminal fitting 106 of the next coil
Let it penetrate inside.

Next, the control unit 2 is placed on the side opposite to the primary and secondary coils of the ignition coil, with the surface on which its circuit components are attached facing the insulating member 3 side, and the iron core 103 is attached to the printed circuit board 20.
1 into the window 202 of the insulating member 3, and the core fitting part 3 of the insulating member 3.
03 into the window part 202, and at the same time the protrusions 307, 3
07' into holes 205 and 205'.

At this time, the printed circuit board 201 comes into contact with the protrusions 304 and is positioned in the longitudinal direction of the iron core.

Further, when assembling the printed circuit board in this manner, the capacitor C is inserted into the capacitor holding portion 315 and held therein.

With the printed circuit board assembled in this manner, the notch 203 of the printed circuit board is aligned with the notch 306 of the insulating member, and the ground terminal fitting 1°6 of the iron core 103 and the secondary coil 1
The terminal fitting 108 of No. 02 penetrates through the notches 306 and 203 and protrudes to the back side of the printed circuit board 201.

Further, the terminal fitting 313 is located on the side of the printed circuit board 201.

Terminal fittings 106 and 10 on the back side of the printed circuit board 201
A conductive layer maintained at a ground potential is formed near 8, terminal fittings 106 and 108 are bent toward this conductive layer (ground potential portion), and both terminal fittings are soldered to the conductive layer. .

Through hole 30 at the center of protrusion 307° 307' of insulating member 3
Primary coil 101 led out by penetrating through 9a and 309b
The lead wires 101a and 101b are soldered to predetermined printed wiring sections provided on the back surface of the printed circuit board 201.

The terminal fitting 313 also has a lead wire (not shown).

) is connected to a predetermined printed wiring section on the printed circuit board.

As described above, the ignition coil 1, control unit 2, and insulating member 3 are integrated.

When the insulating member 3 is provided with a duct-shaped iron core fitting part as in the above embodiment, the fitting part comes into contact with the iron core on a wide surface and is fitted, so even if the dimensional accuracy of the iron core is poor, the insulating member 3 can be stably positioned without greatly tilting the iron core.

In addition, since the dimensional accuracy of the core fitting portion 303 of the insulating member 3 and the dimensional accuracy of the window portion 202 of the printed circuit board 201 can be made sufficiently high, the core fitting portion of the insulating member is fitted to the window portion 202 of the printed circuit board. With this structure, the printed circuit board 201 can be reliably positioned with respect to the insulating member 3.

Furthermore, if the structure is such that the capacitor C is held in the capacitor holding part 315 and the terminal fittings 106 and 108 that pass through the insulating member are soldered to the printed circuit board as in this embodiment, the insulating member and the printed board can be easily connected by a machine. Since they can be firmly bonded together, they can be reliably prevented from moving during molding.

After assembling each part as described above, the end of the winding of the secondary coil 102 and the terminal fitting 311 for the high voltage cord are connected.

In this embodiment, a terminal plate 109 made of copper foil or the like is arranged around the outer periphery of the secondary coil 102, and the secondary coil 109 is placed on this terminal plate.
The end of the winding 02 is soldered, and the terminal plate 109 is connected to the secondary coil 10 with insulating tape so that a part of it is exposed.
It is fixed at 2.

One end of the thin lead wire 7 is soldered to the terminal plate 109, and the other end of the lead wire 7 is soldered to the terminal fitting 311.

The assembly assembled as described above is inserted into the case 6, and one end of the iron core 103 is inserted into the hole 601 at the bottom of the case 6.
mated to.

Positioning protrusions 319, 319 of this sharpening insulating member 3.・
... comes into contact with the inner surface of the case 6 to position the assembly.

Thereafter, a thermosetting insulating resin 6 liquid is injected into the case 6 and cured by heating, and the molded internal combustion engine ignition device is charged and discharged.

After completion, the high voltage cord 4 is press-fitted into the high voltage cord holding portion 310, and the terminal fitting 311 is connected to the core wire of the high voltage cord.

In the above embodiment, the resin is injected into the case 6 and molded by curing. However, the present invention is not limited to such a casting method, and it is possible to perform injection molding without using the case 6. Coil 1 by mold
00, Insulating member 3 and H The control unit 2 may be molded.

In the present invention, since the insulating member 3 and the control unit 2 are firmly positioned with respect to the iron core, they can sufficiently withstand the injection pressure during injection molding.

In particular, in the above embodiment, the lead wire of the primary coil is the protrusion 307,
307', there is no risk of these lead wires moving due to injection pressure, and it is possible to reliably eliminate breakage of the drawing lead wires and accidents of contact with high voltage parts.

In the above embodiment, notches 306 and 203 are provided in the plate-shaped portion 301 of the insulating member and the printed circuit board 201, respectively, and the terminal fittings 106 and 108 are made to protrude to the ground potential side of the printed circuit board through these notches. However, the lead-out structure of these terminal fittings is arbitrary.

For example, an iron core through hole 30 provided in a plate-like portion 301 of an insulating member
The terminal fitting 1 is installed between the core through hole 302 and the core 103 by making the width dimension in one direction of 2 larger than the width dimension of the core 103.
06.108 is formed, and similarly, the width dimension in one direction of the window part 202 of the printed circuit board is made larger than the width dimension of the core fitting part 303, and the core fitting part Terminal fitting 106,1 is installed between 303 and window 202.
A gap may be formed for passing 08.

Further, the terminal fittings 106 and 108 may each penetrate different parts of the insulating member 3 and the printed circuit board 201' and protrude near the ground potential portion of the printed circuit board.

As described above, according to the present invention, the plate portion of the insulating member is interposed between the primary and secondary coils of the ignition coil and the control unit. The distance can be shortened, and the device can be made more compact.

In addition, the iron core is fitted into the duct-shaped iron core fitting part of the insulating member to stably hold the insulating member to the iron core, and the iron core fitting part of the insulating member is fitted into the window part of the printed circuit board to securely hold the insulating member to the iron core. Since the capacitor of the control unit is held in the capacitor holding part provided on the insulating member, the ignition coil, the insulating member, and the control unit can be firmly connected to each other, and each part can be easily connected during molding. You can prevent it from moving.

Therefore, it is possible to prevent parts from coming into contact with each other, wire breakage accidents, etc., and the yield of products can be improved.

[Brief explanation of drawings]

Figures 1 to 7 show an embodiment of the present invention.
Fig. 1 is an overall sectional view, Fig. 2 is a front view showing the primary coil and core of the ignition coil, Fig. 3 is a sectional view showing the secondary coil of the ignition coil, and Fig. 4 is a perspective view of the control unit. , 5th
7 to 7 are a front view, a right side view, and a rear view of the insulating member, respectively. 1...Ignition coil, 101/song/primary coil,
102...Secondary coil, 103...Iron core, 106°108...Terminal fitting, 2...
...Control unit, 3...Insulating member, 301.
...Plate-shaped part, 302 ... Core through hole, 3
03... Iron core fitting part, 315... Capacitor holding part, C... Capacitor.

Claims (1)

[Scope of utility model registration request] An ignition coil formed by winding primary and secondary coils around an iron core, and a printed circuit board disposed on the side of the primary and secondary coils with the plate surface oriented substantially perpendicular to the longitudinal direction of the iron core. A molded internal combustion engine ignition device comprising a control unit to which components constituting a capacitor discharge type internal combustion engine ignition circuit are attached together with the ignition coil, and a molded internal combustion engine ignition device, wherein the primary and secondary coils and the printed circuit board are molded together. A plate-shaped portion interposed between the core fitting portion, which is a substantially duct-shaped iron core fitting portion into which the iron core fits, a capacitor holding portion holding a capacitor of the capacitor discharge type internal combustion engine ignition circuit, and an output end of the secondary coil. An insulating member is provided which integrally has a high voltage cord holding portion that holds an end of the high voltage cord, and the printed circuit board has a window portion that penetrates the iron core fitting portion of the insulating member into which the iron core is fitted. A molded internal combustion engine ignition device characterized by: