JP2583841B2 - Ignition voltage detector for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition voltage detecting device for an internal combustion engine which detects the ignition voltage of a spark ignition type internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, an apparatus for detecting an ignition voltage on a secondary side in an ignition system of an internal combustion engine is known. This is disclosed in JP-A-52-118135,
By winding a band made of a conductor as a sensor outside a high-tension cord (high tension cord) to which a spark plug or the like is connected, a minute capacitor having a dielectric as an insulating material of the high-tension cord is formed, The conductor is connected in series with a measuring capacitor whose one end is grounded. Then, a predetermined signal voltage is obtained in the measuring capacitor according to the principle of electrostatic partial pressure,
It is possible to confirm that an ignition voltage has been generated.

[0003]

However, in order to not only confirm that an ignition voltage is generated but also to accurately measure the waveform of the ignition voltage, the above-described conventional apparatus requires a high-voltage cord. Due to a simple configuration in which a band made of a conductive material is wound around the device, the capacitance easily changes due to vibration, temperature (moisture), and the like, which causes a large fluctuation in the measurement voltage, which causes problems in detection accuracy and durability. there were. In addition, since a high voltage of tens of thousands of volts is close to the device, a large-scale protection circuit is required to cope with a high-voltage leak, and the configuration becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a detection circuit which is excellent in detection accuracy and durability, does not require a protection circuit for coping with high voltage leakage, and is lightweight and compact. It is an object of the present invention to provide an ignition voltage detecting device for an internal combustion engine, which has been developed.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an internal combustion engine having a sensor provided outside a secondary high-voltage cord in an ignition system for detecting the ignition voltage of the internal combustion engine. In the ignition voltage detecting device, the sensor includes a block body made of an insulating material having an insertion hole through which the high-pressure cord is inserted in a watertight manner, and a predetermined interval radially outside the peripheral portion of the insertion hole in the block body. And a ceramic insulator disposed between the insertion hole and the conductor in the block body.

[0006] To achieve the same object, the present invention provides:
In an ignition voltage detection device for an internal combustion engine, wherein a sensor is provided outside a secondary high voltage cord in an ignition system of an internal combustion engine having a plurality of cylinders to detect an ignition voltage of the internal combustion engine, the sensor may be configured such that the high pressure cord is watertight. A block body made of an insulating material having a plurality of insertion holes corresponding to the number of the cylinders, and a predetermined interval radially outside the periphery of the plurality of insertion holes in the block body. And a conductor provided between the insertion hole and the conductor in the block body.

[0007]

In the ignition voltage detecting device for an internal combustion engine according to the first and second aspects of the present invention, a high-voltage cord is inserted in a watertight manner into an insertion hole of a block made of an insulating material, and has a predetermined space radially outward from the high-pressure cord. As a result, the conductor is provided, so that it has excellent durability and insulation properties, and can ensure high detection accuracy and stable output. In addition, since an insulator made of ceramic is provided between the insertion hole and the conductor, corona discharge from the high-voltage cord can be prevented, and the conductor can be brought close to the high-voltage cord, so that the weight and size can be reduced. Also, deterioration of the conductor can be prevented.

[0008]

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

FIG. 1 is a longitudinal sectional view of a sensor in an ignition voltage detecting device for an internal combustion engine according to a first embodiment of the present invention, and FIG. 2 is a partially cutaway plan view of the sensor. In the figure, reference numeral 1 denotes a sensor of an ignition voltage detecting device, which has a block 2 made of an insulating material such as rubber (EPDM) or silicon having a high withstand voltage. The block body 2 has a substantially rectangular cross section, and a plurality of (four in the present embodiment) through holes 3 are formed corresponding to the number of cylinders of an internal combustion engine (not shown).
These insertion holes 3 are located on the same straight line (center line of the block body 2) L whose center is orthogonal to the axis, and are disposed at equal intervals in the direction orthogonal to the axis. .

A secondary high-pressure cord 4 in the ignition system of the internal combustion engine is inserted through each insertion hole 3 in a watertight manner. These high-voltage cords 4 are obtained by covering a core wire 4a with double inner and outer coating layers 4b and 4c. The core wire 4a is
A conductive material made of nichrome wire or the like is wound around a center line made of aramid fiber or the like via an insulating material. The inner coating layer 4b is made of an insulating material such as flexible cross-linked polyethylene or rubber (EPDM) having high withstand voltage. Further, the outer coating layer 4c is made of rubber (EPD) having high withstand voltage.
M). The inner diameter of each insertion hole 3 is set to be larger than the outer diameter of the high-pressure cord 4. Annular lip portions 5 for waterproofing are integrally provided on the inner peripheral surfaces of both ends of each insertion hole 3. The inner peripheral surface of these annular lip portions 5 is in close contact with the outer peripheral surface of the high-pressure cord 4 as shown in FIG. 3, and the annular lip portion 5 allows water to flow between the insertion hole 3 and the high-pressure cord 4. Infiltration is prevented.

In the block 2, conductors 6 are provided corresponding to the respective insertion holes 3. These conductors 6 have an annular (cylindrical) shape concentric with the insertion hole 3. Each of the conductors 6 is located radially outside of the peripheral edge of the insertion hole 3 with a predetermined interval H therebetween. The interval H is a value such that the conductor 6 is not affected by corona discharge from the high-voltage cord 4, and is, for example, about 5 mm to 10 mm. Each conductor 6
Are integrally connected to each other at adjacent portions thereof.
One end (the left end in FIGS. 1 and 2) of the conductor 6 is connected to one end of a conductive line 7 formed of a shield line. The conductive wire 7 is obtained by winding a shield material made of a conductive material around a core wire made of a conductive material via an insulator, and covering the outside thereof with an exterior material made of an insulator. The other end of the conductive wire 7 extends outward from one longitudinal end surface of the block body 2. The signal voltage of the conductor 6 can be taken out of the block 2 by the conductive line 7. An insulator 8 made of ceramic is provided in an annular space between the insertion hole 3 and the conductor 6.

The conductor 6 and the insulator 8 are set in a state where the conductive wire 7 is connected to the conductor 6 in advance, set in a mold for the block 2, and the block 2 is molded. It is molded with the block 2.

The sensor 1 of the ignition voltage detecting device configured as described above is incorporated in an ignition system of an internal combustion engine as shown in FIGS. That is, one end of the high-pressure cord 4 inserted into each insertion hole 3 of the block 2 of the sensor 1 is connected to the spark plug 9.
The other end is connected to the output side of the distributor 10, respectively. In addition, the conductive wire 7 extending outside the block 2 of the sensor 1 is connected to the input side of the detection unit 11. The detection unit 11 and the sensor 1 constitute an ignition voltage detection device. This detection unit 1
The output side of 1 is connected to the input side of the ECU 12. The output side of the ECU 12 is connected to the input side of the distributor 10 via an igniter 13, an ignition coil 14, and a diode 15. FIG.
In the figure, 16 is a power source (battery), the positive electrode of which is a resistor 17
Through the ignition coil 14.
The detection unit 11 has a determination circuit 18 for determining whether or not the ignition voltage is normal. The determination circuit 18 has an operational amplifier 19, a capacitor 21, and resistors 22 and 23.

Next, the operation will be described.

A high voltage is generated on the secondary side because the igniter 13 cuts off the primary current of the ignition coil 14 by an ignition signal output from the ECU 12 in accordance with an ignition timing adjusted and set according to the rotation speed of the internal combustion engine. Then, this high pressure is distributed to the ignition plug 9 of each cylinder via the distributor 10 and the high pressure cord 4, and each cylinder is ignited.

The high voltage, that is, the ignition voltage is detected by the sensor 1, and the detected voltage signal is supplied to the detection unit 11.
The determination circuit 18 compares the ignition voltage with a predetermined voltage value, and determines whether the ignition voltage is normal. The determination signal is input to the ECU 12 as information for adjusting the ignition timing. .

The above operation is the same as in the prior art.

In the present embodiment, the conductors 6 are disposed at predetermined intervals radially outside the periphery of the insertion hole 3 of the block 2 made of an insulating material, and the high-voltage cord 4 is inserted into the insertion hole 3. Is inserted, the conductor 6 is arranged in a state where a predetermined distance is accurately secured to the high-voltage cord 4. For this reason, the bad influence of the conductor 6 due to the corona discharge phenomenon generated from the high-voltage cord 4 can be prevented, the durability of the conductor 6 can be improved, and high detection accuracy and stable output can be obtained.

Further, since the insulator 8 made of ceramic is provided between the insertion hole 3 and the conductor 6, corona discharge from the high-voltage cord is reliably prevented, and the conductor 6 is brought closer to the high-voltage cord 4. Accordingly, the weight and size of the entire sensor 1 can be reduced, and the deterioration of the conductor 6 can be prevented, and the durability of the conductor 6 can be improved.

Further, since the high-voltage cord 4 is inserted into the insertion hole 3 of the block body 2 in a watertight manner, the capacitance of the conductor 6 is hardly affected by vibration, humidity (moisture) and the like. Also,
The diameter of the insertion hole 3 is set to be larger than the outer diameter of the high-pressure cord 4, and watertightness between the insertion hole 3 and the high-pressure cord 4 is secured by the waterproof annular lip portion 5 provided on the inner peripheral surface of the insertion hole 3. Since the high-pressure cord 4 is easily inserted into the insertion hole 3, the watertightness between the insertion hole 3 and the high-pressure cord 4 is ensured.

Further, since the plurality of conductors 6 are integrally connected to each other, only one conductive wire 7 for extracting the signal voltage to the outside of the block body 2 is required, and the size and weight of the entire sensor 1 can be reduced. . In addition, since the conductive wire 7 is a shielded wire, electromagnetic wave resistance and noise resistance are improved, and the influence of disturbance noise on the detection voltage can be prevented.

[Second Embodiment] FIG. 5 is a longitudinal sectional view of a sensor 1 showing a second embodiment of the present invention. In the present embodiment, one plate-shaped conductor 6 having a length covering the entire insertion hole 3 is disposed so as to be deviated to one side in the radial direction with respect to the center of the insertion hole 3, and one end of the conductor 6 is provided. In addition, a conductor 8 is connected, and an insulator 8 made of ceramic is provided on the entire inner surface (side surface of the insertion hole 3) of the conductor 6. Other configurations are the same as those in FIG.
4 are the same as those in the first embodiment shown in FIG.

Third Embodiment FIG. 6 is a longitudinal sectional view of a sensor 1 showing a third embodiment of the present invention. In the present embodiment, a pair of flat conductors 6 having the same insulator 8 as the second embodiment shown in FIG. A projecting wall symmetrically arranged on both sides in the radial direction with respect to the center, one conductive wire 7 is connected to one end of both conductors 6, 6, and integrally projecting from the lower surface of the block body 2. 2a, a slit 24 is provided.
The mounting bracket 25 is inserted into and fixed to the mounting bracket. With this mounting bracket 25, the sensor 1 can be mounted at a predetermined position. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Fourth Embodiment] FIG. 7 is a longitudinal sectional view of a sensor 1 showing a fourth embodiment of the present invention. In the present embodiment, one curved plate-shaped conductor 6 having a length covering the entire insertion hole 3 is disposed so as to be deviated to one side in the radial direction with respect to the center of the insertion hole 3,
A conductive wire 7 is connected to one end of the conductor 6, and an insulator 8 made of ceramic is provided on the entire inner surface (the side surface of the insertion hole 3) of the conductor 6. The curved surface of the conductor 6 is concentric with each of the insertion holes 3. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Fifth Embodiment] FIG. 8 is a longitudinal sectional view of a sensor 1 showing a fifth embodiment of the present invention. In the present embodiment, a pair of curved plate-shaped conductors 6 having the same insulators 8 as those of the fourth embodiment shown in FIG. Are arranged symmetrically on both sides in the radial direction with respect to the center, and one conductive wire 7 is connected to one end of both conductors 6 and 6. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Sixth Embodiment] FIG. 9 is a longitudinal sectional view of a sensor 1 showing a sixth embodiment of the present invention. In this embodiment, the conductor 6 is formed in a U-shape surrounding each insertion hole 3, the conductors 6 corresponding to the respective insertion holes 3 are integrally connected to each other, and the entire inner surface of the conductor 6 is made of ceramic. An insulator 8 is attached, and a mounting bracket 25 is inserted into the projecting wall 2a of the block body 2. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Seventh Embodiment] FIG. 10 is a longitudinal sectional view of a sensor 1 showing a seventh embodiment of the present invention. In this embodiment, the conductor 6 is formed in a substantially square frame shape surrounding each of the insertion holes 3, and the conductors 6 corresponding to the respective insertion holes 3 are integrally connected to each other, and the entire inner surface of the conductor 6 is In addition, an insulator 8 made of ceramic is attached to the protruding wall 2a of the block body 2, and the mounting bracket 25
Is inserted. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Eighth Embodiment] FIG. 11 is a longitudinal sectional view of a sensor 1 showing an eighth embodiment of the present invention. In this embodiment, the conductor 6 has a rectangular frame shape surrounding all the insertion holes 3, and an insulator 8 made of ceramic is formed on the entire inner surface of the conductor 6.
And a slit 2 in the protruding wall 2a of the block body 2.
In FIG. 4, the mounting bracket 25 is inserted and fixed similarly to the third embodiment shown in FIG. Other configurations are the same as those of the first embodiment shown in FIGS.
The same parts in the drawings have the same reference characters allotted, and description thereof will not be repeated.

In the above-described first to eighth embodiments, the arrangement in which the conductor 6 is displaced to one side in the radial direction with respect to the center of the insertion hole 3 is advantageous in that the entire sensor 1 can be made compact. It is.

In the case where the conductor 6 is disposed symmetrically on both sides in the radial direction with respect to the center of the insertion hole 3 (including an annular shape),
This is advantageous in improving and stabilizing the voltage detection accuracy.

Furthermore, the detection accuracy of the shape of the conductor 6 is improved as the area facing the high voltage cord 4 at a certain distance from the high voltage cord 4 is increased (this is advantageous in increasing the capacitance). Ninth Embodiment FIG. 12 is a longitudinal sectional view of a sensor 1 showing a ninth embodiment of the present invention. In the present embodiment, a plurality of insertion holes 3
And its center is located on the same circle line L ₁ around the central portion of the cross section square of the block body 2, and in which is disposed to exist at equal intervals in the circumferential direction. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

FIG. 13 shows a tenth embodiment of the present invention.
It is a longitudinal section of sensor 1 showing an example. In this embodiment,
A substantially rectangular frame-shaped conductor 6 surrounding the whole of the plurality of insertion holes 3 arranged in the same manner as in the ninth embodiment shown in FIG. 12 described above is provided, and the entire inner surface of the conductor 6 is made of ceramic insulation. The body 8 is attached. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Eleventh Embodiment] FIG. 14 shows an eleventh embodiment of the present invention.
It is a longitudinal section of sensor 1 showing an example. In the present embodiment, a radiating plate-shaped conductor 6 is provided at the center of the area surrounded by the plurality of insertion holes 3 arranged in the same manner as the ninth embodiment shown in FIG. An insulator 8 made of ceramic is attached to the entire outer surface of the conductor 6, and one end of one conductor 7 is connected to one piece of the conductor 6. The surface facing the hole 3 is concentric with the insertion hole 3. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

[Twelfth Embodiment] FIG. 15 shows a twelfth embodiment of the present invention.
It is a longitudinal section of sensor 1 showing an example. In the present embodiment, a cross-shaped (radiating plate-shaped) conductor centered on the center is located at the center of the area surrounded by the plurality of insertion holes 3 arranged in the same manner as the ninth embodiment shown in FIG. 6, an insulator 8 made of ceramic is attached to the entire outer surface of the conductor 6, and one end of one conductive wire 7 is connected to one piece of the conductor 6. Other configurations are shown in FIGS.
Since this is the same as the first embodiment shown in FIG. 4, the same reference numerals are given to the same parts in the drawing, and the description thereof will be omitted.

[Thirteenth Embodiment] FIG. 16 shows a thirteenth embodiment of the present invention.
It is a longitudinal section of sensor 1 showing an example. In the present embodiment, a rod-shaped conductor 6 having a substantially square cross section is provided at the center of an area surrounded by a plurality of insertion holes 3 provided similarly to the ninth embodiment shown in FIG. An insulator 8 made of ceramic is provided on the entire outer surface of the conductor 6, and one end of one conductive wire 7 is connected to one corner of the conductor 6. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

FIG. 17 shows a fourteenth embodiment of the present invention.
FIG. 18 is a longitudinal sectional view of the sensor 1 showing the embodiment. In this embodiment, a block 2 is formed in the same shape as a code clamper attached to a cylinder head cover (not shown) of an internal combustion engine. Insertion hole 3
Are provided on the block body 2 along the inner peripheral surface of each of the insertion holes 3 and integrally connected to each other in the block body 2. The entire surface of these conductors 6 is covered with the insulator 8. One end of one conductive wire 7 is connected to the conductor 6 by molding, and a mounting bracket 26 for mounting to the cylinder head cover is provided on the lower surface of the block body 2. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 4 described above, and therefore, the same reference numerals are given to the same portions in the drawings, and description thereof will be omitted.

The ninth to first parts shown in FIGS.
3 an insertion hole 3 as in Example, the center is located on the same circle line L ₁ around the central portion of the cross section square of the block body 2, and then exist at equal intervals in the circumferential direction from each other Due to the arrangement, the sensor 1 is compared with the above-described first to eighth embodiments.
This is advantageous in that the overall shape can be made compact.

In each of the embodiments described above, the case where four insertion holes 3 are provided in the block body 2 has been described. However, the present invention is not limited to this. Are set in accordance with the number of cylinders.

[0039]

As described above, according to the ignition voltage detecting apparatus for an internal combustion engine of the present invention, the sensor structure is formed such that the electric conductor is disposed at a predetermined distance radially outward from the periphery of the insertion hole of the block made of insulating material. Is disposed and the high-voltage cord is inserted into the insertion hole, so that the conductor is disposed in a state where a predetermined distance is accurately secured to the high-voltage cord. Therefore, it is possible to prevent the conductor from being adversely affected by the corona discharge phenomenon generated from the high-voltage cord, improve the durability of the conductor, and obtain high detection accuracy and stable output. In addition, since an insulator made of ceramic is provided between the insertion hole and the conductor, corona discharge from the high-voltage cord is reliably prevented, and
Since the conductor can be brought closer to the high-voltage cord, the weight and size of the entire sensor can be reduced.
Deterioration of the conductor can be prevented, and its durability can be improved. Further, since the high-voltage cord is inserted through the insertion hole of the block body in a water-tight manner, the capacitance of the conductor is hardly affected by vibration, humidity (moisture) or the like. Further, when a sensor having such a structure is provided, a protection circuit for dealing with high voltage leakage is not required.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a sensor in an ignition voltage detection device for an internal combustion engine according to a first embodiment of the present invention.

FIG. 2 is a partially cutaway plan view of the sensor.

FIG. 3 is a system configuration diagram of an ignition system of an internal combustion engine including the device of the present invention.

FIG. 4 is an electric circuit diagram of the system.

FIG. 5 is a longitudinal sectional view of a sensor according to a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a sensor according to a third embodiment of the present invention.

FIG. 7 is a longitudinal sectional view of a sensor according to a fourth embodiment of the present invention.

FIG. 8 is a longitudinal sectional view of a sensor according to a fifth embodiment of the present invention.

FIG. 9 is a longitudinal sectional view of a sensor according to a sixth embodiment of the present invention.

FIG. 10 is a longitudinal sectional view of a sensor according to a seventh embodiment of the present invention.

FIG. 11 is a longitudinal sectional view of a sensor according to an eighth embodiment of the present invention.

FIG. 12 is a longitudinal sectional view of a sensor according to a ninth embodiment of the present invention.

FIG. 13 is a longitudinal sectional view of a sensor according to a tenth embodiment of the present invention.

FIG. 14 is a longitudinal sectional view of a sensor according to an eleventh embodiment of the present invention.

FIG. 15 is a longitudinal sectional view of a sensor according to a twelfth embodiment of the present invention.

FIG. 16 is a longitudinal sectional view of a sensor according to a thirteenth embodiment of the present invention.

FIG. 17 is a perspective view of a sensor according to a fourteenth embodiment of the present invention.

FIG. 18 is a longitudinal sectional view of the sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor 2 Block body 3 Insertion hole 4 High voltage cord 5 Annular lip part 6 Conductor 7 Conductive wire 8 Insulator H Predetermined interval

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masatake Kanahiro 1-4-1, Chuo, Wako-shi, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Inventor Shigeki Baba 1-4-1, Chuo, Wako-shi, Saitama Inside Honda R & D Co., Ltd. (72) Inventor Takuji Ishioka 1-4-1 Chuo, Wako-shi, Saitama Pref. Inside Honda R & D Co., Ltd. (56) References JP-A-4-370372 (JP, A) JP-A-4 −298685 (JP, A)

Claims (9)

(57) [Claims] 1. An ignition voltage detecting device for an internal combustion engine, wherein a sensor is provided outside a secondary high-voltage cord in an ignition system of the internal combustion engine to detect an ignition voltage of the internal combustion engine. A block body made of an insulating material having an insertion hole that is inserted in a watertight manner; a conductor disposed at a predetermined interval radially outside a peripheral portion of the insertion hole in the block body; An ignition voltage detecting device for an internal combustion engine, comprising: an insulator made of ceramic disposed between the insertion hole and the conductor. 2. An ignition voltage detecting device for an internal combustion engine, wherein a sensor is provided outside a secondary side high pressure cord in an ignition system of an internal combustion engine having a plurality of cylinders to detect an ignition voltage of the internal combustion engine. A block body made of an insulating material having a plurality of insertion holes in which the high-pressure cords are inserted in a watertight manner corresponding to the number of cylinders, and a predetermined distance radially outward from a peripheral portion of the plurality of insertion holes in the block body; An internal combustion engine, comprising: a conductor disposed in the presence of an insulator; and an insulator made of ceramic disposed in the block body between the insertion hole and the conductor. Ignition voltage detector. 3. The plurality of insertion holes are characterized in that their centers are located on the same straight line perpendicular to the axis, and are arranged at equal intervals in the direction perpendicular to the axis. The ignition voltage detecting device for an internal combustion engine according to claim 2, wherein 4. A center of the plurality of insertion holes is located on the same circle centered on a central portion of the block body, and is arranged at equal intervals in a circumferential direction. The ignition voltage detecting device for an internal combustion engine according to claim 2, characterized in that: 5. The ignition of an internal combustion engine according to claim 1, wherein the conductor is disposed so as to be deviated to one side in a radial direction with respect to a center of the insertion hole. Voltage detector. 6. The ignition voltage detection for an internal combustion engine according to claim 1, wherein the conductor is disposed symmetrically on both sides in the radial direction with respect to the center of the insertion hole. apparatus. 7. The ignition voltage detecting device for an internal combustion engine according to claim 2, wherein the conductors corresponding to the plurality of insertion holes are integrally connected to each other. 8. An inner diameter of the insertion hole is larger than an outer diameter of the high-pressure cord, and water enters between at least the inner peripheral surfaces of both ends of the insertion hole between the insertion hole and the high-pressure cord. 8. The ignition voltage detecting device for an internal combustion engine according to claim 1, further comprising a waterproof annular lip portion for blocking. 9. The ignition voltage detection for an internal combustion engine according to claim 1, wherein a signal voltage of said conductor is taken out of said block body via a conductive wire formed of a shield wire. apparatus.