JPH0230981A - Distributor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power distribution device for an internal combustion engine, and particularly to a power distribution device having a function of reducing noise radio waves generated between a rotating electrode and a fixed electrode.

[Conventional technology]

BACKGROUND ART Among the ignition devices of internal combustion engines such as automobiles, noise radio waves generated during discharge of a power distributor and a spark plug have a wide frequency band, and therefore may cause radio wave interference to various wireless communications. Therefore, in order to suppress harmful noise radio waves generated by these ignition devices.

Various measures are being taken to reduce noise radio waves.

In order to reduce the noise radio waves generated by spark plugs, the combined use of resistor-containing spark plugs and resistor-containing high-voltage wires has been put into practical use, and its effectiveness has been recognized. On the other hand, as a means for reducing noise radio waves generated from power distributors, Japanese Patent Laid-Open No. 57-262
No. 70, JP-A-57-195871, JP-A-58-2
As disclosed in Japanese Utility Model Application Publication No. 0966 and Japanese Utility Model Application Publication No. 59-13672, a method has been proposed in which a dielectric is added to the tip discharge portion of a metal electrode of a power distributor to reduce the discharge voltage.

[Problem to be solved by the invention]

It has been found that the above conventional technology has the following problems. As disclosed in Japanese Patent Application Laid-open No. 57-26270, there is a method of lowering the discharge voltage by using a metal with low thermal conductivity such as stainless steel as an electrode and combining the thermionic radiation effect and the dielectric addition effect. However, in this method, the temperature of the electrode increases significantly, so if used for a long period of time, both the electrode and the dielectric material will be seriously damaged. In such a state, the discharge voltage increases and the noise radio wave reduction effect deteriorates.

Also, JP-A-57-195871, JP-A-58-20
966 and Japanese Utility Model Application Publication No. 59-13672, there is also a method of attaching a dielectric material to a metal electrode using a silicone adhesive or the like to reliably lower the discharge voltage.

However, when these are used for a long period of time, the adhesive deteriorates due to the thermal effects of discharge, causing the dielectric to separate from the electrode.

The effect of adding the resin plate becomes smaller. Therefore, the discharge voltage increases and the noise radio wave reduction effect deteriorates.

An object of the present invention is to provide a power distributor that has a good noise radio wave reduction effect during long-term use.

[Effect]

The present invention will be described in detail below based on the drawings.

FIG. 15 shows a cross section of a power distribution section of a power distributor to which the present invention is applied. It is attached to an internal combustion engine by a housing 9 and a camshaft 15. The camshaft 15 is mounted so as to rotate in conjunction with the rotary drive shaft of the internal combustion engine, and a distribution element 17 having a rotating electrode 16 attached to the upper surface of an insulator is mounted on the upper part. A plurality of fixed electrodes 11 are provided in the circumferential direction of this rotating electrode 16, and a power distribution gap 10 in which a central terminal 12 is fixedly installed near the center is attached to the housing 9.

Explain the operation of a power distributor. Rotating electrode 16 and fixed electrode 11
When the ignition coils reach their opposing positions, the high voltage generated by the actuation of the primary current interrupter of the ignition coil is transmitted to the rotating electrode 16 via the center terminal 12, the spring 14, and the carbon contact 13. After electrical power is distributed to the fixed electrode 11 by dielectric breakdown of the air in the minute gap 18 between the tip and the fixed electrode 11, it is supplied to the ignition plug. At this time, the discharge generated between the rotating electrode 16 and the fixed electrode 11 causes the generation of noise radio waves.

It is known that the cause of the generation of noise radio waves is a state in which a large current flows in an impulse manner between the floating capacitance existing between the rotating electrode 16 and the fixed electrode 11 at the initial stage of discharge, that is, a capacitive discharge current. . In order to reduce noise radio waves, it is possible to reduce the capacitance discharge current, but since capacitance has a limit value determined by the shape of the power distributor, it is impossible to reduce it significantly. Rather, it is necessary to lower the discharge starting voltage. is appropriate.

On the other hand, it is known that the discharge starting voltage can be significantly lowered by using a rotating electrode or a fixed electrode with a dielectric added thereto.

However, as shown in Fig. 12, if a rotating electrode made of a laminated stainless steel plate 6 and silicone resin plate 7 (dielectric material) with low discharge voltage characteristics is used for a long period of time, the running distance will decrease as shown in Fig. 13. The discharge voltage increases as
It has been found that there is a drawback that the amount of radio noise increases.

The reason for this is that, as shown in FIG. 14, a gap 8 is generated at the joint 2 between the stainless steel plate and the silicone resin plate during use, which weakens the effect of lowering the discharge voltage due to the addition of the dielectric.

Therefore, in order to prevent the discharge voltage from increasing, the gap generation during use should be made as small as possible by 4X. However, the electrode of the stainless steel plate 6 becomes hot during discharge.

Therefore, the silicone resin plate 7 laminated on the stainless steel plate 6 is affected by the heat of the stainless steel plate 6, causing thermal deformation, burnout, etc., and in the end, the generation of the gap 8, which causes an increase in discharge voltage, can be avoided in this electrode. do not have.

In addition, as a countermeasure to this problem, improvements have been made in which the stainless steel plate 6 and the silicone resin plate 7 are joined without any gaps using a silicone adhesive, but the adhesive deteriorates after long-term use and the silicone resin plate 7 peels off, burns out, etc., resulting in gaps, and this is not an effective measure to prevent gaps.

The feature of the present invention is that, as shown in FIG. 6, a metal is used for the electrode so that the tip discharge part 5 of the electrode slightly melts due to electric discharge, and a dielectric material 3 is installed on the lower surface of the metal electrode 1. There is a particular thing. If you do this.

The tip discharge portion 5 of the gold@electrode 1 is melted by the discharge, forming a tip melting portion 4 that comes into close contact with the dielectric 3 placed on the lower surface of the metal electrode 1. This action takes place every time a discharge occurs, so for example,
Is there a gap between the metal electrode 1 and the dielectric 3 due to thermal deformation or burnout in the dielectric 3? Even if III gaps occur, molten metal flows into the locations where these gaps occur, suppressing the generation of gaps, and making it possible to maintain the discharge voltage at a constant low level even after long-term use.

The metal electrode material used in the present invention is preferably a metal with a melting point of 1083° C. or lower. Particularly preferred are copper and copper metal, tin and tin alloys, lead and lead alloys, zinc and zinc alloys, and the like. In addition, since this metal has a smaller electrode temperature rise during discharge than stainless steel, it also has the advantage of less uneven heat loss in the dielectric.

The dielectric material is glass fiber cloth impregnated with silicone resin.

Molded products of alumina, magnesia, silica, titania, etc. may be used.

Further, the metal electrode and the dielectric material are melted into close contact with each other. There is also an advantage that there is no need to stick them together using an adhesive or the like as in the prior art.

Note that the effect of the present invention is greater when applied to the electrode that becomes the negative electrode during discharge, so in commonly used power distributors, the present invention is applied to the rotating electrode that is connected to the negative electrode during discharge. It is better to apply it.

[Means to solve the problem]

The feature of the present invention is that a metal having a melting point of 1083° C. or less is used for the discharging portion at the tip of at least one of the rotating electrode and the fixed electrode of the power distributor, and a dielectric plate is disposed on the lower surface of the metal.

〔Example〕

<Example 1> FIG. 1 shows an example of a rotating electrode of a power distributor according to the present invention.

The electrode was made by laminating a silicone resin-impregnated glass fiber cloth 20 with a thickness of 0.5 mm over the entire lower surface of a brass plate (JIS, C2600) 19 with a thickness of 0.6 mm. The second is the result of measuring the discharge voltage and the size of the gap generated in the electrode when a 100,000 km running test was conducted using the electrode of the present invention. According to this, the discharge voltage of the product of the present invention is 3.8
~4.4kV, the gap is O~0.04mm, and even if the running cline increases, the increase in discharge voltage and gap is extremely small.
It has a good noise reduction effect even after long-term use. In addition,
In addition to this embodiment, the same effects as in this embodiment can be obtained even when metals such as pure copper, red bronze, bronze, and phosphor bronze are used as the electrode material.

〈Example 2〉 Fig. 3 shows another example of the invention of the rotating electrode of the power distributor according to the present invention.
The electrode is made by laminating silicone resin-impregnated glass fiber cloth 20 mm thick. Fig. 4 shows the 100,000 k
These are the results of measuring the discharge voltage and the size of the gap generated between the electrodes during the m running test. According to this, the discharge voltage of the product of the present invention is 4-4.5kv, and the gap is O-0.05m.
Even if the running distance increases, the increase in discharge voltage and gap is extremely small, and it has a good noise radio wave reduction effect even after long-term use. In addition to this embodiment, the same effect as in this embodiment can be obtained even when a tin alloy such as Bahit metal is used as the electrode material.

<Embodiment 3> FIG. 5 shows another example of the invention of the rotating electrode of a power distributor according to the present invention, in which a thickness of 0.5
The electrode is made by laminating silicone resin-impregnated glass cloth 20 mm thick. FIG. 6 shows the results of measuring the discharge voltage and the size of the gap generated in the electrode when a 100,000 km running test was conducted using the electrode of the present invention. According to this, the discharge voltage of the product of the present invention is 4.1 to 4.4 kv, and the gap is 0 to 0.04 mm.
Even if the running distance increases, the increase in discharge voltage and gap is extremely small, and it has a good noise radio wave reduction effect even after long-term use. In addition to this embodiment, the same effect as in this embodiment can be obtained even when a lead alloy such as white metal is used as the electrode material.

<Embodiment 4> Fig. 7 shows another example of the invention of the rotating electrode of a power distributor according to the present invention, in which a 0.5 m thick zinc plate 23 with a thickness of 0.5 m is provided on the entire lower surface of the zinc plate 23 with a thickness of 1 mm.
The electrode is made by laminating silicone resin-impregnated glass cloth 20 of m. FIG. 8 shows the results of measuring the discharge voltage and the size of the gap generated in the electrode when a 100,000 km running test was conducted using the electrode of the present invention. According to this, the discharge voltage of the product of the present invention is 3.9 to 4.6 kv, and the gap is O to 0.05 m+n.
Even if the running distance increases, the increase in discharge voltage and gap is extremely small, and it has a good noise radio wave reduction effect even after long-term use. In addition to this embodiment, the electrode material may be made of a zinc alloy such as ZDC, and the same effects as in this embodiment can be obtained.

<Example 5> Fig. 9 shows another example of the invention of the rotating electrode of the power distributor according to the present invention, in which a brass plate (JIS) with a thickness of 0.6 mm is used.

A molded alumina plate 24 having a thickness of 0.5 mm is laminated on the entire lower surface of the C2600) 19. FIG. 15 shows the results of measuring the discharge voltage and the size of the gap generated in the electrode when a 100,000 km running test was conducted using the electrode of the present invention. According to this, the discharge voltage of the product of the present invention is 4 to 4.5 kv.
The gap is 0 to 0.05111 m, and even if the running distance increases, the increase in discharge voltage and gap is extremely small, and it has a good noise radio wave reduction effect even after long-term use. In addition to this embodiment, the same effect as in this embodiment can be obtained even when a molded body of a refractory material such as magnesia, silica, titania, etc. is used as the dielectric material.

〔Effect of the invention〕

According to the present invention, noise radio waves generated from a power distributor can be effectively reduced over a long period of time, and electrodes can be easily manufactured using inexpensive materials.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an electrode according to an embodiment of the present invention, Fig. 2 is a graph showing the measurement results of the discharge voltage and gap generated in the electrode when the electrode of Fig. 1 is used, and Fig. 3 is a graph of the present invention. A perspective view of an electrode according to another embodiment of the invention, FIG. 4 is a graph showing the measurement results of the discharge voltage and the gap generated in the electrode when the electrode of FIG. 3 is used, and FIG. Perspective view of electrode of Example, No. 6
The figure is a graph showing the measurement results of the discharge voltage and the gap generated in the electrode when using the electrode shown in Fig. 5, Fig. 7 is a perspective view of an electrode according to another embodiment of the present invention, and Fig. 7 is a graph showing the measurement results of the discharge voltage when using the electrode and the gap generated in the electrode, FIG. 9 is a perspective view of a black electrode according to another embodiment of the present invention, and FIG. Figure 9 is a graph showing the measurement results of the discharge voltage when using the electrode and the gap generated in the electrode, Figure 11 is a cross-sectional view of the electrode to which the present invention is applied, and Figure 12 is a graph of the electrode of the prior art. A cross-sectional view, Fig. 13 is a graph showing the measurement results of discharge voltage when using the electrode shown in Fig. 12, and Fig. 14 shows the measurement result of the gap generated in the electrode when using the electrode shown in Fig. 12. The graph and FIG. 15 are main part sectional views showing the power distribution section of the power distributor. DESCRIPTION OF SYMBOLS 1...Metal electrode, 3...Dielectric, 4...Tip melting part, 6...Stainless steel plate, 7...Silicone resin plate, 8...Gap, 11...Fixed electrode, 12...Rotating electrode, 19...Brass plate, 2o...Silicone resin impregnated glass fiber cloth, 21...
・Tin plate, 22γ/lead plate. 23...Zinc plate, alumina plate. Fig. 1: De-Yuuha Gen Fig. A beggars large flL (X/θ4) Fig. 22: Yoshiya Fig. Ma-itei y big skin * (xtty' ni place) Fig. 8 Fig. 7A, Bamboo y large separation (starved to X/θ4) Fig. 11 Fig. 12 * Fig. 10 Distance (x/θ4 position) Possible diagram

Claims (1)

[Claims] 1. A rotating electrode that rotates in conjunction with a rotating shaft of an internal combustion engine;
In a power distributor for distributing high voltage to a spark plug via a fixed electrode facing the rotating electrode with a gap, at least a distal end discharge portion of the rotating electrode and/or the fixed electrode is made of a metal having a melting point of 1083° C. or less. A power distributor characterized in that a dielectric material is disposed at least at a discharge tip portion of the rotating electrode and/or the fixed electrode except for a discharge facing surface of the rotating electrode and/or the fixed electrode. 2. Claim 1, characterized in that at least the tip discharge portion of the rotating electrode and/or the fixed electrode is made of a metal with a melting point of 1083° C. or lower, and a dielectric is disposed on the lower surface of the tip discharge portion. A power distribution device. 3. The power distributor according to claim 2, wherein copper or a copper alloy is used for at least the distal end discharge portion of the rotating electrode and/or the fixed electrode. 4. The power distributor according to claim 2, wherein tin or a tin alloy is used for at least the distal end discharge portion of the rotating electrode and/or the fixed electrode. 5. The power distributor according to claim 2, wherein lead or a lead alloy is used for at least the distal end discharge portion of the rotating electrode and/or the fixed electrode. 6. The power distributor according to claim 2, wherein zinc or a zinc alloy is used for at least the tip discharge portion of the rotating electrode and/or the fixed electrode. 7. Claim 2, characterized in that a resin obtained by impregnating glass fiber with silicone resin is used for the dielectric material disposed on the lower surface of at least the tip discharge part of the rotating electrode and/or the fixed electrode. A power distribution device. 8. Claim 2, wherein the dielectric material disposed at least on the lower surface of the tip discharge part of the rotating electrode and/or the fixed electrode includes alumina,
A power distributor characterized by using a molded body of an inorganic refractory such as magnesia, silica, titania, etc.