JPS58170860A - Ignition device of internal-combustion engine - Google Patents

Abstract

PURPOSE:To prevent the generation of noises by a method wherein a pair of photosensors each comprising a photo-emissive element and a photo-receiving element are made integral with a unit comprising a control section and a switching section so that no space for mounting a photosensor and the circuit and no intermediate wiring is required. CONSTITUTION:A photo-diode 2a generates a pulsating signal in correspondence to the output circuit 20a of an oscillator 20. Even in case no incident light flux L2 on a photo-transistor 4a from a projection 3f of an object to be detected 3 is absent, a synchronous signal 20b is transmitted from the oscillator 20 to a synchronous detector 21. Next, when the object 3 to be detected is rotated to come to a position at which the effective light flux L2 becomes incident on the transistor 4a, a detecting signal is transmitted from the photo-receiving section 4, demodulated by the synchronous signal 20b, inputted to a next stage integrator 22, integrated every time when the detecting output is inputted to the integrator and finally becomes zero when no more detecting output is inputted. Such integrated output is received by a waveform shaping section 23 and when it is higher than a regulated level, an ignition coil 8 is energized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a contactless internal combustion engine ignition system that uses a photoelectric sensor to detect rotational position.

The basic configuration of this type of device is as shown in FIG.

That is, in FIG. 1, (11 is a constant current source, (2) is a light emitting unit consisting of a light emitting diode, etc., (3) is a rotational position detector that is driven by the engine and rotates in synchronization with the engine, (4)
) is a light receiving section consisting of a phototransistor etc., (5) is an amplifying section that amplifies the photocurrent photoelectrically converted in the light receiving section, (61
1 is a waveform processing unit that performs waveform processing for the purpose of various controls, (7) is a switching unit consisting of a power transistor, etc., and (8) is an ignition coil.

Among the above configurations, the conventional device has the light emitting section (2) and the light receiving section (4) integrated and provided close to the detection object (3), and on the other hand,
The constant current source (11, amplification part (5), waveform processing part (6), and switching part (7) were integrated and used separately from the detection object (3). Therefore, the light receiving part (4) ) to the amplifying part (5), and the signal level there was also very small, making it susceptible to external noise.Also, the amplifying part (
5) Space was needed to install a unit that would house the following items.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above.
By making everything except 1 and the ignition coil (8) into an integrated structure, there is no need for intermediate wiring as in conventional devices, making it possible to create a system that is resistant to external noise, and is small, lightweight, and space-saving. be.

Next, two types of embodiments of the present invention will be described.

First, the configuration for the DC light blocking type is shown in Figure 1, $2.
The operating waveforms are shown in FIG. 3, and the structure is shown in FIG. 4.

That is, in Fig. 2, (1a) is a constant current source that supplies a constant DC current, (2a) is a light emitting diode, L is the luminous flux of the light emitting diode (2a), and (3a) is the detector (3). The constituent rotating disk is provided with notches at every predetermined angle to allow light to pass through at the speed of light L1.L2 is the light flux that passes through the rotating disk (3a), and (4a) is the phototransistor. , (4b), (5b), (5a) is a resistor, (5a) C is a transistor for increasing width, (7a) is a power transistor, (8) is an ignition coil, and +91 is a DC power supply.

The above-mentioned parts are integrated in a structure as shown in FIG.

That is, the rotating disk (3!L) is driven by the shaft (3c) and has a notch (3b). The light emitting diodes (5) and phototransistors (5) face each other, and the rotating disk (worm) rotates between them. On the other hand, a board 0υ on which a circuit pattern is printed and wired is pasted on the top surface of the heat sink Ql, and the board ←
At a predetermined location on the surface of υ, a semiconductor chip 2 in which the amplifying section 15) and the waveform processing section (6) are integrated into an integrated circuit is mounted, and a power transistor (7a) is also mounted. A terminal (7b) is drawn out from the collector of the power transistor (7a), and a casing Qa) is provided to surround the terminal (7b). and C4
is a unit that integrates all of the above.

The operation of the first embodiment configured as above will be described next.

First, when the DC power supply (9) is connected to the entire device, the constant current source (1a) supplies a constant DC current to the light emitting diode (2a).
Continue to flow as shown in Figure 3. As a result, the light emitting diode (2a) continues to emit a luminous flux L1 having a constant amount of light. Next, when the engine rotates and the disc (3a) starts to rotate in synchronization with it, the above luminous flux L1 is affected by the presence or absence of the notch (3b) in the disc (3a), and first of all, there is no notch. In this case, the light beam L1 cannot pass through, so the phototransistor (4a) is not activated and does not conduct. As a result, the transistor (5a) also does not conduct, and as a result, the power transistor (7a) conducts and the ignition coil (8) receives current (&L).
flow. Next, when the notch (3b) of the disk (3a) begins to face the front surface of the light emitting diode (2a), the light flux Ll becomes a light flux L2 and passes through the phototransistor (the light fluxes L1 and L2 are the same). (4a) is activated and conductive. As a result, the transistor (5a) also becomes conductive, and as a result, the power transistor (7a) becomes non-conductive, and the ignition coil (
The current (8a) of 81 is cut off and a high ignition voltage is generated. As described above, in this embodiment, the DC light L+1 emitted from the light emitting diode (upper) is transferred to the rotating disk (3a).
This is the simplest and most common method in which the phototransistor (4a) is interrupted and the operation of the phototransistor (4a) is interrupted.

Next, the configuration of the second embodiment of the modulated light reflection type is shown in FIG. 5, the operating waveforms are shown in FIG. 6, and the structural diagram is shown in FIG. 7. First, in FIG. The output waveform of the oscillator is a pulse waveform as shown in waveform (20a) in FIG. As shown in the cross-sectional view of FIG. 7, the position detector is driven by the engine by a shaft (γ), and has a support (3e) and projections (3f) at predetermined angles. (5 ) is an amplifying section, C11 is a synchronous detection section, ■ is an integrating section, θ is a waveform shaping section, (7) is a switching section, and (8) is an ignition coil.

Also, in Figure 7, (2a) is a light emitting diode, (4a)
is a phototransistor, (24 is a heat sink, ■ is a printed wiring board, (to) is a semiconductor chip in which the circuit from 51 to the shaping part is integrated into an integrated circuit, (
7a) is a power transistor, (7b) is its collector terminal, and (2) is a casing part provided so as to surround each of the above parts. And [Yes] is a unit that integrates all of the above.

Note that the outer peripheral surface of the protrusion (3f) is a light emitting diode (2).
It has a mirror finish so that it can sufficiently reflect the light beam L1 from a), and the phototransistor (4a) is arranged at a position where it can most efficiently receive the effective reflected light beam L2.

Next, the operation will be explained. First, the oscillator (1) continues to oscillate to generate a rectangular wave current (20a) at a sufficiently high constant frequency. In response to this oscillator output current (20a), the light emitting diode (2a) emits light and emits a luminous flux Lt in the form of a pulse as shown in FIG. Now, when the protrusion (3f) of the detection object (3) is rotated to a position where it is not in a position facing the light emitting diode (top) and the phototransistor (4a), there is no light flux L2 incident on the phototransistor (4a), and therefore no light is received. There is no output from section (4), that is, no input signal to the synchronous detection section. Note that even in this state, the synchronous detection section (211
A synchronizing signal (20b) is sent from the oscillator (2) to the oscillator (20b). Next, the detection body (3) rotates and its protrusion (3)
f) reflects the luminous flux Ll from the light emitting diode (2a) to produce a luminous flux L2 effective for the phototransistor (4a).
When it reaches a position where it is incident, a detection signal is sent from the light receiving section (4) via the middle section (5), and the signal is detected by the synchronous detection section Q old iron synchronization signal (20b).
It becomes the detection output (21b) and is input to the next stage integrator@. The integrator (2) integrates the detected output (21a) one step at a time to a high potential every time one pulse enters, and conversely, as soon as the detected output disappears, the integrated output is discharged to zero. The waveform is like the waveform (22a') in Fig. 6.The threshold level of the waveform shaping section that operates in response to the integrator output (22a) is (23a). The level J
The output (23b) is output only when there is the above integrator output (22a) on a, and this output (23b)
In response to this, a switching section (7) consisting of a power transistor (7a) energizes an ignition coil (8).

As described above, in this second embodiment, a modulated light pulse is created by the output pulse of the oscillator (a), and the resulting light flux Ll is emitted toward the rotational position detector,
The reflected light flux L2 is photoelectrically converted, extracted and integrated in synchronization with the oscillator output pulse, and a pulse waveform with the necessary time width is obtained, which energizes the ignition coil. This is an excellent method for reducing the influence of temperature changes on the light emitting section and the light receiving section.

FIG. 8 shows an embodiment in which the unit charge according to the $2 embodiment described above is built into the power distributor (40).

In Fig. 8, gloss is the housing, cll) is the ball bearing, Q is the drive shaft, (to) is the camshaft, (c) is the unit (5) mounting base provided on the inner surface of the housing circle,
In the figure, the leader line from the unit [with], (c) is the centrifugal advance device, (36) is the power distribution rotor, (37) is the cap, and in the figure, the rotational position detector (3) is the camshaft ( The drive shaft (32) is fixed to the drive shaft (38) through this camshaft.
). Since the unit is made to be extremely small, it is fixed on the mounting base (33) inside the housing.
The light emitting diode (A) and phototransistor (4a) shown in Figure 87 are facing the detection object (3).

As described above, the unit (5) can be installed inside the power distribution device (40), but on the other hand, the detection object (3) can be installed outside the power distribution device, for example, on a part of the crankshaft or camshaft, and the unit can be mounted opposite to it. This is easy to provide since the unit is extremely small.

As described above, this invention has a structure in which a pair of photoelectric sensors consisting of a light emitting and a light receiving element are integrated into a conventional unit consisting of a control section and a switching section. No installation space is required, and the only wiring required is the power supply line and ignition coil line, eliminating the need for intermediate wiring, making it more resistant to external noise.In addition, it can be built into a power distribution device, contributing to smaller size and lighter weight. There are many effects that can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing a first embodiment of the present invention, Fig. 2 is an electric circuit diagram of the first embodiment, Fig. 3 is an operation waveform diagram of the first embodiment, and Fig. 4 is a jl diagram. ! Structural diagram of Example 1, No. 5
The figure is a configuration diagram showing an embodiment of gJ2, FIG. 6 is an operation waveform diagram of the second embodiment, FIG. 7 is a structural diagram of the second embodiment, and FIG.
The figure is a sectional view showing another structure showing the second embodiment. In the figure, (3) is a rotational position detector, +21. (2a)
is the light emitting part, f4+, (4a) is the light receiving part, +51. +
61. (211, (23, (23) are control units, (81
is the ignition coil, +71. (7a) is a switching section;
(40) is a power distributor. In the figures, the same reference numerals indicate the same or corresponding parts. Agent Makoto Kuzuno - Figure 1, Figure 2, Figure 3, Figure 5, Figure 6, Figure 7, Figure 8

Claims (1)

[Claims] (11) A rotational position detector driven by an engine and rotated in synchronization with the engine, a light emitting unit that emits a luminous flux toward the detector, and receiving a luminous flux from the light emitting unit via the detector. A light receiving section, which amplifies the electrical signal photoelectrically converted by the above light receiving section,
In an internal combustion engine ignition system comprising a control section that performs waveform processing, and a switching section that operates according to a signal from the control section and switches on and off the current in the ignition coil, at least the light emitting section, the light receiving section, the control section, and the switching section are provided. An internal combustion engine ignition device characterized by having an integrated structure. (2) Claim 1, characterized in that the light emitting section, the light receiving section, the control section, and the switching section are built into the power distribution device.
Internal combustion engine ignition system as described in .