JPH084640A - Rotation angle detection device for internal combustion engine - Google Patents

Abstract

PURPOSE:To provide a rotation angle detection device for an internal combustion engine which protects a control circuit of a rotational angle detection device by the detection device itself against an electromagnetic noise due to a distributor in the internal combustion engine, corresponds to downsizing of the distributor of the internal combustion engine, and highly resist against the electromagnetic noises. CONSTITUTION:A detector 19 detects rotation. A power device part 30 has a power transistor 13 which connects and disconnects a primary voltage of an ignition coil. A control circuit 12 has function which shapes waveform of the rotational detection signal and switching function which drives the power device 30. The control circuit 12 is shielded from an electromagnetic noise generated by discharging at a distributor. A radiating metal plate 14 for heat radiation from the power device 30 is arranged between the detector 19 and the control circuit 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detection device for detecting a rotation angle, and more particularly to a rotation angle detection device built in a distributor for an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, as an ignition power transistor integrated rotation angle detection device incorporated in a distributor for an internal combustion engine, there is a technique described in Japanese Patent Laid-Open No. 4-203358.

According to this conventional technique, due to the structure of the detecting device, the detecting portion and the control circuit portion of the detecting device are close to the power distributing portion of the distributor, so that the electromagnetic noise due to the discharge of the distributing portion can be taken into consideration. It wasn't done.

[0004]

DISCUSSION OF THE INVENTION In the distribution of internal combustion engines, there is a trend toward miniaturization due to needs, and it is considered that the distance between the power distribution unit and the detection device will become shorter and shorter. On the other hand, the detection device must be protected by some means.

An object of the present invention is to protect the control circuit section of the detection device against electromagnetic noise from the power distribution unit by the detection device itself, and to cope with downsizing of the internal combustion engine power distributor.
An object of the present invention is to provide a rotation angle detection device having high resistance to electromagnetic noise.

[0006]

In order to achieve the above object, the present invention provides a power distribution section for discharging a high voltage induced by an ignition coil to a power distribution side electrode through a power distribution rotor, and a crank of an internal combustion engine. A distributor for an internal combustion engine, comprising a rotating body that rotates in synchronization with a shaft and has a signal disconnecting means for detecting a rotation signal, the distributor being arranged inside the distributor for an internal combustion engine. A detection part having a detection element for detecting an angular position from the rotation of the electric field and converting it into an electric signal, a power transistor for connecting and disconnecting the primary voltage of the ignition coil by the electric signal, and a heat dissipation metal plate to which the power transistor is attached. Rotation angle for internal combustion engine having a power device unit and a control circuit unit having a function of shaping the waveform of the detected rotation signal and a switching function of driving the power device In the output device, the heat dissipation metal plate is arranged between the power distribution unit and the control circuit unit, and between the detection unit and the control circuit unit, and a rotation angle detection device for an internal combustion engine. I will provide a.

[0007]

The basic idea of the present invention is to electromagnetically cut off the power distribution unit and the control circuit unit of the rotation angle detection device in the internal combustion engine power distributor, and to shield the metal body between the power distribution unit and the control circuit unit. Is to apply. There is a metal plate for heat dissipation as a member with a shielding effect among the components of the rotation angle detection device.Therefore, with the rotation angle detection device attached to the distributor housing, the metal plate for heat dissipation is installed in the control circuit section and the power distribution section. Place it so that it exists between them. As a result, it is possible to obtain a shield effect of protecting the control circuit unit from electromagnetic noise due to discharge of the power distribution unit. Further, by connecting the metal plate for heat dissipation to the terminal of zero potential, the shield effect can be further increased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An internal combustion engine rotation angle detecting device according to an embodiment of the present invention will be described below.

FIG. 1 is a partial cross-sectional view of a distributor for an internal combustion engine using the rotation angle detecting device of the present invention. A rotating disk 3 having a slit as an optical interrupter on a shaft 2 supported by a housing 1 which is a main body of a distributor, and a distribution rotor 4.
Is attached. A rotation angle detecting device 5 for detecting a rotation angle is attached to the housing 1 by a slit of the rotating disk 3, an ignition coil 6 for igniting an internal combustion engine is built in, and a synthetic resin having a distribution side electrode 7 is provided. It is covered with a cap 8. The power distribution unit 9 includes the ignition coil 6
The high voltage induced by is discharged from the coil electrode to the distribution side electrode 7 through the distribution rotor 4.

FIG. 2 shows a rotation angle detecting device 5 used in FIG.
3 is a sectional view (section AA in FIG. 3) of FIG. The rotation angle detection device 5 includes a detection unit 19 that detects the rotation of the slit of the rotating disk 3 by the optical elements 10 and 11, a power device unit 30 that includes a power transistor 13 that connects and disconnects the primary voltage of the ignition coil 6, and a rotation unit. The control circuit section 12 has a function of shaping the waveform of the detection signal and a switching function of driving the power device 30, and these parts are supported by a synthetic resin case 33. The power device unit 30 includes a power transistor 13 and an insulating plate 3.
1 and the insulating plate 31 are sandwiched between the power transistor 13
The heat-dissipating metal plate 14 is attached. The heat-dissipating metal plate 14 is made of a material such as copper or aluminum that has good thermal conductivity and is resistant to electromagnetic noise.

Further, the rotation angle detecting device 5 includes a detecting section 19
The heat-dissipation metal plate 14 used for heat dissipation of the power device section 30 is disposed between the control circuit section 12 and the control circuit section 12. Specifically, in a cutout portion provided in a part of the heat dissipation metal plate 14,
The detection unit 19 held by a part of the synthetic resin case 33 is fitted and projected, and the control circuit unit 12 is arranged on the side opposite to the detection unit 19 with the metal plate 14 for heat radiation interposed therebetween. Further, the heat-dissipating metal plate 14 is electrically connected to the zero-potential terminal 17 via the connecting wire 15. As a result, it is possible to sufficiently obtain the shield effect of protecting the control circuit unit 12 from the electromagnetic noise caused by the discharge of the power distribution unit 9.

FIG. 3 shows the external shape of the rotation angle detecting device 5 of FIG. 2 are given the same reference numerals. The arrangement of the receiving metal fitting 16a for mounting the rotation angle detecting device 5 on the housing 1 is shown. Further, the heat generated in the power device unit 30 is radiated from the heat radiating metal plate 14 to the housing 1 via the receiving metal fitting 16a. At this time, the outer diameter portion in contact with the heat-dissipating metal plate 14 is enlarged so that the receiving metal fitting 16a has a heat-dissipating effect so as not to impair the original heat-dissipating function of the heat-dissipating metal plate.

FIG. 4 is a BB of the rotation angle detecting device 5 of FIG.
3 shows a cross section. 2 are given the same reference numerals. The connecting wire 15 is used in a method of electrically connecting the connecting portion between the receiving metal fitting 16a and the heat radiating metal plate 14, and the control circuit portion 12 and the power device portion 30. The connection with the connecting wire 15 is not easily affected by distortion and vibration during assembly of parts, and the electrical connection is reliable and stable. Therefore, there is a shield effect of protecting the control circuit unit 12 from electromagnetic noise. In order to obtain a heat dissipation effect, it is preferable that the receiving metal fitting 16a has a larger outer diameter portion than the other receiving metal fitting 16b and is made of a material having good thermal conductivity, such as copper or aluminum.

FIG. 5 is a sectional view of a conventional rotation angle detecting device 5. Since the heat-dissipating metal plate 14 does not exist between the detection unit 19 and the control circuit unit 12, the shield effect against electromagnetic noise due to the discharge of the power distribution unit 9 is small. Further, since the electrical connection between the control circuit unit 12 and other parts is made by the lead frame 18, it may be easily affected by distortion and vibration at the time of assembling the parts, and the electrical connection may become unstable. , Generally weak against electromagnetic noise.

FIG. 6 shows the structure and appearance of another embodiment. The same parts as those in FIG. 3 are designated by the same reference numerals. The basic configuration and external shape are the same as in FIG. The signal connecting / disconnecting means is composed of a rotating vane 23 having a magnetic shutter instead of the rotating disk 3, and the rotation detecting element is composed of a hall element 21 and a permanent magnet 20 instead of the optical elements 10 and 11. Other configurations are the same as those of the rotation angle detection device 5 of FIG. Further, the effect of electromagnetic noise and the heat dissipation effect are the same as those of the rotation angle detection device 5 of FIG.

As described above, according to the present invention, by disposing the heat radiating metal plate having the shielding effect between the power distribution unit and the control circuit unit, it is possible to increase the resistance of the power distribution unit to electromagnetic noise.

[0017]

As described above, according to the present invention, a rotation angle detecting device having a high resistance to electromagnetic noise can be realized, and the degree of freedom of the arrangement position of the rotation angle detecting device on the internal combustion engine distributor can be increased. It is effective for downsizing of electric distribution machines for engines.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a distributor for an internal combustion engine that incorporates a rotation angle detection device of the present invention.

FIG. 2 is a sectional view of a rotation angle detection device used in FIG.

FIG. 3 is a diagram showing an external shape of the rotation angle detection device of FIG.

4 is a cross-sectional view of the rotation angle detection device of FIG.

FIG. 5 is a sectional view of a conventional rotation angle detection device.

FIG. 6 is a diagram showing a configuration and an external shape of another embodiment.

[Explanation of symbols]

1 ... Housing, 2 ... Shaft, 3 ... Rotating disk, 4 ... Distribution rotor, 5 ... Rotation angle detecting device, 6 ... Ignition coil,
7 ... Side electrode, 8 ... Cap, 9 ... Power distribution part, 10, 11 ...
Optical element, 12 ... Control circuit section, 13 ... Power transistor, 14 ... Heat dissipation metal plate, 15 ... Connection wire, 16
a, 16b ... Receiving metal fitting, 17 ... Terminal, 18 ... Lead frame, 19 ... Detecting section, 20 ... Permanent magnet, 21 ... Hall element, 23 ... Rotating vane, 30 ... Power device section, 33 ... Synthetic resin case

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiaki Kaminaga 2477 Kashima Yatsu, Katsuta-shi, Ibaraki Pref. 3 Hitachi Hitachi Engineering Co., Ltd. (72) Inventor Ryoichi Kobayashi 2520 Takaba, Katsuta-shi, Ibaraki Shares Company Hitachi, Ltd. Automotive Equipment Division

Claims (7)

[Claims] 1. A power distribution unit for discharging a high voltage induced by an ignition coil to a power distribution side electrode via a power distribution rotor, and a signal interrupting unit for rotating a rotation signal for rotating in synchronization with a crankshaft of an internal combustion engine. A distributor for an internal combustion engine having a rotating body having a detecting element arranged inside the distributor for the internal combustion engine, which detects an angular position from rotation of the signal interrupting means of the rotating body and converts it into an electric signal. A detection unit having, a power device unit having a power transistor for connecting and disconnecting the primary voltage of the ignition coil by the electric signal, and a heat dissipation metal plate to which the power transistor is attached, and a function of waveform-shaping the detected rotation signal And a rotation angle detecting device for an internal combustion engine having a control circuit section having a switching function for driving the power device, wherein the heat dissipation metal plate is connected to the power distribution section and the front section. The rotation angle detection device for an internal combustion engine, wherein the rotation angle detection device is arranged between the control circuit sections and between the detection section and the control circuit section. 2. The heat-dissipating metal plate according to claim 1,
A rotation angle detecting device for an internal combustion engine, which is connected to a terminal of zero potential. 3. The rotation angle detecting device for an internal combustion engine according to claim 1, wherein the control circuit section and another electrical connection section are connected by wire bonding. 4. The rotating disk according to claim 1, wherein a pair of light receiving and emitting photoelectric elements are used as the detection elements of the detection section, and the rotating body has slits that are formed as annular portions at predetermined intervals as the signal connecting / disconnecting means. Is a rotation angle detecting device for an internal combustion engine. 5. The detection device according to claim 1, wherein a hole element is used as a rotation detecting element of the detecting section, and the detecting section is provided with a permanent magnet having a function of generating a hole voltage in the hole element.
A rotation angle for an internal combustion engine, characterized in that the rotating body is provided with a rotating vane in which shutters of a magnetic body for blocking magnetic flux acting on the hall element from the permanent magnet are arranged at predetermined intervals. Detection device. 6. The synthetic resin case for holding the power device unit according to claim 1, wherein at least two receiving metal fittings for mounting the heat-dissipating metal plate are provided, and at least one outer shell is in contact with the heat-dissipating metal plate. A turning angle detection device for an internal combustion engine, characterized in that a diameter portion is enlarged. 7. A power distribution unit for discharging a high voltage induced by an ignition coil to a power distribution side electrode through a power distribution rotor, and a signal interrupting means for rotating a rotation signal for rotating in synchronization with a crankshaft of an internal combustion engine. A distributor for an internal combustion engine having a rotating body having a detecting element arranged inside the distributor for the internal combustion engine, which detects an angular position from rotation of the signal interrupting means of the rotating body and converts it into an electric signal. A detection unit having, a power device unit having a power transistor for connecting and disconnecting the primary voltage of the ignition coil by the electric signal, and a heat dissipation metal plate to which the power transistor is attached, and a function of waveform-shaping the detected rotation signal. And a rotation angle detecting device for an internal combustion engine, which comprises a synthetic resin case holding a control circuit unit having a switching function for driving the power device, The detection part held in a part of the synthetic resin case is fitted into a notch part provided in a part of the metal plate for heat to protrude, and the side opposite to the detection part is sandwiched with the metal plate for heat dissipation. A rotation angle detecting device for an internal combustion engine, characterized in that the control circuit section is provided in the.