JPH0441254Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ignition device for an internal combustion engine used to ignite the engine.

[Prior Art] Capacitor discharge type ignition devices are often used as ignition devices for internal combustion engines. Figure 9 shows the configuration of a capacitor discharge type ignition device that is driven by the output of an exciter coil installed in a magnet generator driven by an internal combustion engine. In the figure, 1 is the exciter coil, and 2 is the ignition coil. ,3
is a control circuit unit that controls the primary current of the ignition coil. One end of the exciter coil 1 is grounded, and the other end is connected to a terminal fitting 4. A power terminal fitting 5 of the control circuit unit is in contact with the terminal fitting 4, and an anode of a diode D1 is connected to this terminal fitting 5. An ignition energy storage capacitor C1 is connected to the cathode of the diode D1.
One end of the capacitor C1 is connected, and the other end of the capacitor C1 is 1
The primary coil 2 of the ignition coil via the secondary terminal fitting 6
connected to one end of a. The other end of the capacitor C1 is also connected to the anode of a diode D2, and the cathode of the diode D2 is connected to the other end of the primary coil 2a via a primary terminal fitting 7. The anode of the discharge control thyristor Th1 is connected to one end of the capacitor C1, and the thyristor Th1
The cathode of is connected to a line connected to the terminal fitting 7. One end of the resistor R1 and the anode of the Zener diode Z1 are connected to the gate of the thyristor Th1, and the other end of the resistor R1 is connected to the thyristor Th.
1 cathode. One end of a resistor R2 and an anode of a diode D3 are connected to the cathode of the Zener diode Z1, the other end of the resistor R2 is connected to the cathode of the thyristor Th1, and the cathode of the diode D3 is connected to the cathode of the diode D1. Also, diode D1
A diode D4 with its cathode facing the diode D1 side is connected between the anode of the thyristor Th1 and the cathode of the thyristor Th1, and a diode D5 with its anode facing the cathode side of the thyristor Th1 is connected between the cathode of the thyristor Th1 and the anode of the diode D3. is connected. The cathode of the diode D5 and one end of the secondary coil of the ignition coil are connected to a power terminal fitting 8 on the ground side, and the power terminal fitting 8 is connected to a grounded terminal fitting 9. The other end of the secondary coil 2b of the ignition coil is connected to the non-ground terminal of a spark plug 11 attached to a cylinder of the engine via a secondary terminal fitting 10 and a high voltage cord connected to the secondary terminal fitting. has been done.

In this example, diodes D1 to D5, a Zener diode Z1, an ignition energy storage capacitor C1, a discharge control thyristor Th1,
A capacitor discharge type control circuit unit 3 is constituted by the resistors R1 and R2.

The electronic components constituting the control circuit unit 3 are printed circuit boards as shown in FIGS. 10 and 11.
The ignition device 20 is attached to a PC, and the substrate PC and ignition coil 2 are housed in a case 15 to form an ignition device 20. A partition plate 15a is provided inside the case 15 to divide the inside of the case into an ignition coil storage chamber 15A and a circuit board storage chamber 15B.The ignition coil 2 is placed in the storage chamber 15A, and the circuit board PC is placed in the board storage chamber 15B. It is stored. Since the ignition energy storage capacitor C1 is relatively large, it is placed on top of other electronic components in the board storage chamber 15B, and the connection means 16 that connects the board PC and the ignition coil 2 is connected to the partition plate 15a. It is provided through a gap 15c provided in the center of the. An insulating resin 17 such as epoxy is injected into the space inside the case 15.

In the above ignition system, exciter coil 1
induces an alternating current voltage in synchronization with the rotation of the internal combustion engine. The half-cycle output voltage of one polarity of the exciter coil 1 charges the capacitor C1 to the polarity shown through the diode D1, the diode D2, the primary coil 2a of the ignition coil, and the diode D6. Next, when a half-cycle voltage of the other polarity is induced in the exciter coil 1, the following happens: exciter coil 1 → Zener diode Z1 → gate cathode of thyristor Th1 → diode D4
→A trigger signal is given to thyristor Th1 through the path of the exciter coil, and thyristor Th1 becomes conductive. As a result, the charge in the capacitor C1 is discharged through the thyristor Th1 and the primary coil 2a of the ignition coil, and a high voltage for ignition is induced in the secondary coil 2b due to the magnetic flux change that occurs at this time. Since this high voltage is applied to the ignition plug 11, a spark is generated at the ignition plug and the engine is ignited.

[Problems to be solved by the invention] In the conventional ignition system in which the ignition coil and the control circuit unit are housed in a common case, the capacitor C1 is placed on top of other electronic components. There was a problem in that a large dead space DS (the shaded area in FIG. 11) was created around the capacitor C1, and the amount of resin injected into the case increased. In addition, in order to place the capacitor C1 on top of other electronic components, it is necessary to make the lead wire of the capacitor C1 considerably long and bend the lead wire, so it is necessary to insulate the lead wire. It was inevitable that the assembly of the control circuit unit would be troublesome.

In addition, in conventional ignition devices of this type, the connection between the ignition coil and the circuit board was made near the center of the board, which made soldering work difficult and the assembly work complicated. There was a problem with becoming.

In addition, with conventional ignition devices, it was necessary to position the ignition coil and control circuit unit individually within the case before resin was cast into the case, making the positioning work troublesome and manufacturing complicated. There was a problem.

An object of the present invention is to provide an ignition device for an internal combustion engine that solves the above problems.

[Means for Solving the Problems] The present invention provides an internal combustion engine in which an ignition coil and a control circuit unit for controlling the primary current of the ignition coil are housed in a case, and an insulating resin is injected into the case. In an engine ignition system, in the present invention, a pair of ignition coils connected to both ends of a primary coil of an ignition coil are used.
A secondary terminal fitting and a pair of power terminal fittings connected to the ignition power source are arranged side by side on one end side in the axial direction of the ignition coil, and the pair of primary terminal fittings and the pair of power terminal fittings are connected to the ignition coil. and fix it.

Further, the control circuit unit is arranged close to the ignition coil with the board surface of the printed circuit board parallel to the axis of the ignition coil and with a predetermined gap between the control circuit unit and the ignition coil.

The primary terminal fitting and the power terminal fitting are provided with a board connecting portion protruding toward the printed circuit board, and the board connecting portion is soldered to the conductive portion of the printed circuit board.

The capacitor is arranged at the other end of the ignition coil in the axial direction, aligned with the ignition coil in the axial direction, and facing the printed circuit board with a small gap therebetween. Furthermore, the capacitor is provided with a pair of lead wires that protrude toward the printed circuit board in a state that faces each other in a direction perpendicular to the axis of the ignition coil.
Solder the paired leads to the printed circuit board.

Furthermore, a flat insulating partition plate is integrally provided in the case to partition between the control circuit unit and the ignition coil and between the control circuit unit and the capacitor. and the gap between the capacitor and the control circuit unit. The distance between the pair of lead wires of the capacitor is set to a size that allows insertion of the partition plate.

[Operation of the invention] When the ignition energy storage capacitor is placed at one end of the ignition coil in the axial direction as described above,
Since no large dead space is created within the case, the entire structure can be made compact, and the amount of resin injected into the case can be reduced.

Furthermore, when the primary terminal fitting and the power terminal fitting are arranged side by side on one end of the ignition coil as described above, the connection between both ends of the primary coil of the ignition coil and the primary terminal fitting, and the connection between the secondary coil and the power terminal fitting are possible. All the connections between the ignition coil and the primary terminal fitting can be made at the end of the same side of the ignition coil, thereby simplifying the connection work between the ignition coil and the primary terminal fitting. In addition, by dipping the ends of the printed circuit board into a molten solder bath, each terminal fitting and the board can be connected at once.
Connection work between the ignition coil and the board can be easily performed.

Further, when the ignition energy storage capacitor is arranged side by side with the ignition coil as described above, the capacitor can be arranged close to the circuit board, so that the length of the lead wire of the capacitor can be sufficiently shortened. Therefore, insulation treatment of the capacitor lead wires can be omitted, and the capacitor can be easily attached. Further, by arranging the capacitor at a position apart from each terminal fitting as described above, insulation design can be facilitated.

Furthermore, as described above, the primary terminal fitting and the power terminal fitting fixed to one end of the ignition coil are soldered to the printed circuit board, and the capacitor is soldered to the printed circuit board to connect the ignition coil, the capacitor, and the control circuit. When the units are interconnected and a partition plate integrally provided in the case is inserted into the gap between the ignition coil and the control circuit unit and the gap between the capacitor and the control circuit unit,
By inserting the ignition coil, control circuit unit, and capacitor into the case, these positions can be automatically performed. Therefore, it is possible to omit the work of individually positioning the ignition coil, control circuit unit, and capacitor within the case prior to pouring resin into the case, thereby reducing assembly man-hours and facilitating manufacturing. I can do it.

[Embodiments] Examples of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show an embodiment of the present invention, and the electrical configuration of this embodiment is similar to the example shown in FIG. 9. In Figures 1 and 2, 2 is an ignition coil, 3 is a capacitor discharge type control circuit unit that controls the primary current of the ignition coil, and the ignition coil 2 is made of laminated steel plates as seen in Figure 3. A rod-shaped iron core 201 configured by
A resin bobbin 202 fitted into the bobbin 20
The primary coil 2a is wound around 2, and the primary coil 1 is wound separately.
Secondary coil 2b fitted around the outer periphery of secondary coil 2a
It consists of a primary coil 2a and a secondary coil 2b.
is molded by a resin mold part 203. A flange plate portion 204 is provided at one end of the bobbin 202, and a cylindrical high-voltage cord insertion portion 205 is integrally provided on a part of the outer periphery of the flange plate portion 204. A wood screw-shaped high voltage terminal fitting 206 is fixed to the bottom of the high voltage cord insertion part 205, and the high voltage terminal fitting 206 is screwed into the core wire of the high voltage cord 21 (see Fig. 1) inserted into the high voltage cord insertion part 205. The high-voltage terminal fitting 206 and the high-voltage cord 21 are connected in a state where the high-voltage terminal fitting 206 and the high-voltage cord 21 are bitten into each other.

At both widthwise ends of the bobbin collar plate 204, there are
In the figure, terminal fitting engagement grooves 207a and 207b are formed that are open downward and on both left and right sides, and a fourth
A power terminal metal fitting 5 having a shape as shown in the figure is inserted and held. This power terminal fitting 5 includes a tongue-shaped contact piece 5a, a locking part 5b bent at right angles from the base of the contact piece, and an extension part 5c extending from the locking part 5b parallel to the plate surface of the contact piece 5a. And this extension part 5c
The board connecting part 5d is formed to have a width narrower than that of the extension part 5c. This terminal fitting 5 has its locking portion 5b engaged in the engagement groove 207a, and the collar plate portion 20
4 is locked. The power terminal fitting 8 that is paired with the power terminal fitting 5 is formed in a shape symmetrical to that shown in FIG.
b, an extension part 8c, and a board connection part 8d. This power terminal fitting 8 has a second locking portion 8b.
Terminal fitting engagement groove 207 located on the right side in the figure
b and is locked to the flange plate portion 204.
In this way, the power terminal fittings 5 and 8 are attached to the collar plate part 204.
In the attached state, the respective board connection parts 5d and 8d protrude further outward in parallel from the outer peripheral surface of the molded part 203 of the ignition coil, and the contact piece 5a
and 8a protrude in a direction parallel to the axial direction of the ignition coil 1.

The collar plate portion 204 also includes power terminal fittings 5 and 8.
Lead-shaped primary terminal fittings 6 and 7 are fixed so as to be located on the inner side and on substantially the same plane as the extensions 5c and 8c of the power terminal fittings 5 and 8. In this example, a protrusion 208 is provided on the collar plate 204.
a and 208b are provided, and the terminal fittings 6 and 7 are fixed to the collar plate portion by elastically engaging these protrusions into holes provided in the terminal fittings 6 and 7. Board connecting portions 6d and 7d are provided at the tips of the terminal fittings 6 and 7, respectively, to align with the substrate connecting portions 5d and 8d of the power terminal fittings 5 and 8.

As shown in FIG. 5, the winding start end 2b1 of the secondary coil 2b is connected by wrapping and soldered to the terminal fitting 8, and the primary coil is connected to the terminal fittings 6 and 7, respectively. The winding start end 2a1 and the winding end end 2a2 of 2a are connected by wrapping and then soldered. A plurality of projections 209 are provided radially on the outer circumference of the flange plate portion 204, and these projections contact the inner surface of the case, which will be described later, so that a predetermined gap is maintained between the ignition coil 2 and the inner surface of the case. It's getting old.

The printed circuit board PC has a conductive circuit made of copper foil on one side a (the wiring part that connects electronic components)
is constructed, and electronic components 30 other than the ignition energy storage capacitor, such as the thyristor Th1, diodes D1 to D5, and resistors R1 and R2, are arranged on the side a on which the conductive circuit is constructed (hereinafter referred to as the copper foil surface). These electronic components are soldered to predetermined portions of the conductive circuit of the circuit board PC. These electronic components can be soldered all at once using a reflow oven.

The circuit board PC is placed close to the ignition coil with its copper foil surface a and its opposite surface b facing toward the ignition coil 2, with its plate surface parallel to the axial direction of the ignition coil. The circuit board PC is arranged such that one end thereof is located near one end of the ignition coil (the end on the side where the terminal fittings 5 to 8 are provided) and the other end extends beyond the other end of the ignition coil. It is formed longer than the axial length of the ignition coil. The board connection parts 5d to 8d of the terminal fittings 5 to 8 attached to the flange plate part 204 of the bobbin of the ignition coil 2 pass through holes provided at one end of the circuit board PC so that their respective tips are connected to the copper foil surface a side of the board PC. These board connection parts are soldered to predetermined parts of the conductive circuit of the board PC, and the ignition coil 2 and the control circuit unit 3 are electrically and mechanically connected.

The ignition energy storage capacitor C1 consists of a capacitor body 31 formed in a substantially rectangular plate shape and a pair of lead wires 32, 32 protruding from the capacitor body toward the control circuit unit. It is arranged so as to be aligned with the ignition coil in the axial direction on the other end side. The capacitor C1 is disposed with the main surface 31a of its main body perpendicular to the axial direction of the ignition coil, and has lead wires 32, which face each other in the direction perpendicular to the ignition coil axis.
32 passes through the printed circuit board PC and is soldered to a predetermined portion of the copper foil surface a of the board. In this embodiment, the main body 31 of the capacitor C1 and the substrate
A predetermined gap d is formed between the PC and the outer peripheral surface of the molded part 203 of the ignition coil 2 and the PCB.
The same gap d is also formed between.

In this embodiment, the connection relationship between the terminal fittings 5 to 8 and each part of the control circuit is the same as the example shown in FIG. coil 1
A terminal fitting 4 connected to the non-ground side terminal and a terminal fitting 9 connected to the ground are connected.

As shown in FIG. 6, the case 40 that houses the ignition coil 2 and the control circuit unit 3 has a case body 41 formed in a box shape with one end open and facing the opening 41a of the case body 41. A flat insulating partition plate 42 extending from the surface toward the opening 41a, a mounting plate portion 43 extending from one corner of the case body 41 in a direction perpendicular to the plate surface of the insulating partition plate 42, and the mounting plate portion 43. Rib 44 to reinforce
The mounting plate portion 43 has a mounting hole 45 formed therein. The capacitor C1
The distance between the pair of lead wires is set to be greater than or equal to the width of the insulating partition plate 42 so that the insulating partition plate 42 can be inserted therein. The insulating partition plate 42 contains the ignition coil 2 and the control circuit unit 3 within this case.
When the lead wire 3 of capacitor C1 is inserted
2 and 32 so that it can fit into the gap d between the ignition coil and the circuit board,
The ignition coil 2 and control circuit unit 3 are installed in the case 4.
0, a partition plate 42 is interposed between the ignition coil 2 and the circuit board PC to insulate the two. Since the ignition coil 2 and the control circuit unit 3 are connected to each other via the terminal fittings 5 to 8, it is easy to insert them into the case.

After the ignition coil and control circuit unit are inserted into the case 40 as described above, the insulating resin 50 is injected into the case. In this embodiment, the width dimension of the insulating partition plate 42 is smaller than the inner width dimension of the case body 41, and a gap S is formed between both ends of the insulating partition plate 42 in the width direction and the inner surface of the case body 41. Therefore, the flow of the insulating resin can be improved, and the parts housed in the case can be molded with the resin without any gaps, thereby improving the insulation performance.

As mentioned above, in the present invention, the terminal fitting 5
- 8 are arranged side by side on one end of the ignition coil, it is easy to connect the coil conductor to these terminal fittings 5 - 8, and the terminal fittings 5 - 8 and the copper of the circuit board PC can be easily connected. Soldering with foil is
This can be done all at once by dipping one end of the circuit board PC into a bath of molten solder.

Further, in the present invention, since the capacitor C1 is located on the opposite side of the terminal fittings 5 to 8 and is separated from them, the insulation design between the ignition coil and the circuit board can be facilitated.

As described above, the electronic component 30 is placed on the copper foil surface a of the printed circuit board PC having copper foil on one side, and the ignition coil 2 is placed on the copper foil side b of the circuit board.
In the case of arranging it toward the side, the partition plate 42 of the case 40 can be omitted as shown in FIGS. 7 and 8.

Note that the present invention is not limited to the case where the electronic components are arranged on the copper foil surface a of the board as described above, but also when the electronic components 30 are arranged on the side opposite to the copper foil surface of the printed circuit board PC. The lead wires of each electronic component may be passed through the board and soldered to the copper foil surface, and the circuit board may be arranged with the copper foil surface facing the ignition coil 2 side.

[Effects of the invention] As described above, according to the invention, since the ignition energy storage capacitor is placed at one end of the ignition coil in the axial direction, it is possible to prevent the creation of a large dead space within the case, thereby reducing the overall It is possible to have a compact structure and reduce the amount of resin injected into the case. In addition, the board connection parts of the primary terminal fitting and the power terminal fitting are arranged side by side on one end of the ignition coil, so both ends of the primary coil of the ignition coil and the primary terminal fitting are connected, and the power terminal fitting and the ignition coil are connected to each other. All the connections between the coil and the secondary coil can be made at the ends on the same side of the ignition coil, and the connection work between the ignition coil and the primary terminal fitting and the power terminal fitting can be simplified. Further, by dipping the ends of the printed circuit board into a molten solder bath, each terminal fitting and the board can be connected at once, so the connection work between the ignition coil and the board can be easily performed. In addition, an ignition energy storage capacitor is placed side by side with the ignition coil, the capacitor is opposed to the circuit board with a small gap, and a pair of lead wires protruding from the capacitor toward the board are connected to the circuit board. Since it is soldered, the length of the capacitor lead wire can be made sufficiently short. Therefore, insulation treatment of the capacitor lead wires can be omitted, and the capacitor can be easily attached. Furthermore, since the capacitor is arranged at a position apart from each terminal fitting, the insulation design between the ignition coil and the control circuit unit can be facilitated.

Further, according to the present invention, the primary terminal fitting and power terminal fitting fixed to one end of the ignition coil are soldered to a printed circuit board, and the capacitor is soldered to the printed circuit board, so that the ignition coil and the capacitor are connected to each other by soldering to the printed circuit board. Since the circuit units are interconnected and the partition plate integrally provided in the case is inserted into the gap between the ignition coil and the control circuit unit and the gap between the capacitor and the control circuit unit, the ignition By inserting the coil, control circuit unit, and capacitor into the case, these positions can be automatically performed. Therefore, it is possible to omit the work of positioning the ignition coil, control circuit unit, and capacitor within the case prior to resin casting, which has the advantage of reducing assembly man-hours and facilitating manufacturing. .

[Brief explanation of the drawing]

FIG. 1 is a front longitudinal sectional view showing an embodiment of the present invention;
FIG. 2 is a right side view of the same embodiment, and FIGS. 3A and 3B are front sectional views and left side views showing the ignition coil used in the same embodiment and the control circuit unit attached to the ignition coil, respectively. Figure 4 is a perspective view showing the power terminal fitting used in the same example, Figure 5 is a detailed view of the vicinity of the terminal metal fitting part in the same example, and Figure 6 is a partially cutaway view of the case used in the same example. A perspective view, FIG. 7, and FIG. 8 are a front vertical sectional view and a right side view showing other embodiments of the present invention, respectively, and FIG. 9 shows an electrical configuration of a control circuit unit used in an embodiment of the present invention. 10 is a sectional view showing a conventional example, and FIG. 11 is a sectional view taken along line A--A in FIG. 10. 2...Ignition coil, 3...Control circuit unit,
5, 8... Power terminal fitting, 5, 6... Primary terminal fitting, 30... Electronic components constituting the control circuit, 40
...Case, PC...Printed circuit board, C1...Ignition energy storage capacitor.

Claims (1)

[Claims for Utility Model Registration] An ignition coil comprising a primary coil wound around a bobbin fitted to an iron core, and a secondary coil wound around the primary coil, and one of the ignition coils. A control circuit unit for controlling the next current is housed in a case, and an insulating resin is injected into the case. and components of a discharge control circuit for discharging the electric charge of the capacitor to the primary coil of the ignition coil, which are soldered to a printed circuit board. A pair of primary terminal fittings connected to both ends and a pair of power terminal fittings connected to an ignition power source are arranged side by side on one end side in the axial direction of the ignition coil, and the pair of primary terminal fittings and a pair of power terminal fittings are connected to the power source. and a terminal fitting is fixed to the ignition coil, and the control circuit unit has a board surface of the printed circuit board parallel to the axis of the ignition coil and a predetermined gap between the control circuit unit and the ignition coil. the primary terminal fitting and the power terminal fitting have a board connecting part protruding toward the printed circuit board, and the board connecting part is soldered to a conductive part of the printed circuit board. the capacitor is disposed on the other end of the ignition coil in the axial direction, aligned with the ignition coil in the axial direction, and facing the printed circuit board with a slight gap therebetween; a pair of lead wires protruding toward the printed circuit board in a direction perpendicular to the axis of the ignition coil; the pair of lead wires are soldered to the printed circuit board; A flat plate inserted into the gap between the ignition coil and the control circuit unit and the gap between the capacitor and the control circuit unit to partition between the control circuit unit and the ignition coil and between the control circuit unit and the capacitor. An ignition device for an internal combustion engine, characterized in that an insulating partition plate is integrally provided in the case, and a distance between the pair of lead wires of the capacitor is set to a size that allows the partition plate to be inserted. .