JPS6043178A - Ignition timing control device - Google Patents

Abstract

PURPOSE:To prevent the deterioration of output at high land by a method wherein the amount of spark advance is uniformly increased at the high land to eliminate the delay of ignition timing due to the effect of a vacuum spark angle advancing device. CONSTITUTION:The output signal of an altitude sensor 16 is inputted into a voltage converting circuit 25 in a knocking control unit 17. When the output signal of the altitude sensor 16 has become high at the high land, the voltage level of the voltage converting circuit 25 is shifted as a whole to the low voltage side of a reference point in accordance with the increase of the output signal. According to this method, the delay of ignition timing due to the vacuum spark angle advancing device may be eliminated and, therefore, the deterioration of the output at the high land may be prevented.

Description

[Detailed description of the invention]

The present invention provides a 1νl control device i! at the time of ignition of a vehicle engine.
? In particular, the present invention relates to optimal control of ignition timing at high altitudes. In general, the ignition timing control device applies a negative pressure corresponding to the opening of the throttle valve of the intake system to the vacuum advance device installed in the gay rib coater, and advances the ignition timing according to the load.
) is configured. In addition, since knocking is likely to occur in engines with a supercharger, the ignition timing at the time of knocking is retarded, so knock control is provided with a sensor that detects vibrations in the engine body: knock from the L unit. The signal is input to an igniter built into the distributor, and the amount of retardation is increased according to the intensity of the knock signal. However, since the advance angle control by the vacuum advance device described above is performed using the differential pressure between atmospheric pressure and boat negative pressure, if the atmospheric pressure on the reference side decreases at high altitudes, the ignition timing will change due to the slope compared to levelland. I was running late. For this reason, there are problems in that output decreases and fuel efficiency worsens at high altitudes. Therefore, there is a prior art technique disclosed in Japanese Unexamined Patent Application Publication No. 5G-81242 as a conventional countermeasure for high-altitude ignition timing. Taking this into account, the ignition timing is determined to be equal to that on the flat ground.Therefore, according to this prior art, with the same throttle valve, the boat negative pressure is smaller on the high ground than on the flat ground. Furthermore, the ignition timing tends to be delayed, which is undesirable.In view of the problem of such ignition (!11 ff,!) control at high altitudes, the present invention uniformly increases the advance angle motherboard at high altitudes to increase the vacuum advance angle. It is an object of the present invention to provide an ignition timing control device that eliminates the delay in ignition timing caused by a knock control system. Focusing on retard control, this is used to advance the ignition timing at altitude, and the ignition timing on flat ground is controlled when the voltage level of the output signal of the knock control system is high and the ignition timing is actually retarded. Matching

[At high altitudes, the gist is to shift to the advance side by reducing the 76-kilometer level of the output signal of the knock control system based on the output signal of the Takaishi sensor. Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. In the figure, first, a supercharged engine to which the present invention is applied will be explained. Reference numeral 1 indicates supercharged engine,
The suction side of the compression I tube 18 is connected to the J aflow meter 4 directly downstream of the air cleaner 3 via the duct 2, and the discharge side thereof is connected to the intake pipe 5 and the throttle body 7 on the right side of the throttle valve 6.
, communicates with the engine body 9 via the intake manifold 8. Furthermore, a trachea 10 from the engine body 9 is configured to communicate with the turbine 1b of the supercharger 1, and the supercharger 1 is driven by exhaust energy at a predetermined engine speed or higher, thereby achieving supercharging. It is designed to work. On the other hand, the ignition timing control device is operated for a predetermined period of time immediately upstream of the throttle valve 6 in the
Negative pressure take-off boats 1 to 11 are provided at downstream locations, and this boat 11 communicates with a positive pressure retard type vacuum advance device 14 of a distributor 13 via a passage 12. In addition, a knock sensor +J15 that is attached to a predetermined location on the engine body 9 to detect its vibration, and an altitude sensor 16 that outputs an I signal depending on the altitude are connected to the knock control unit L7. Voltage signals corresponding to advance and retard angles are sent to the distributor 13.
The signal is input to the igniter 18, which is built in the igniter 18. Furthermore, the ignition coil 19 is activated at the ignition timing determined by the igniter 18.
The high voltage is distributed to the spark plugs of each cylinder via the power distribution section of the distributor 13. In FIG. 2, the knock control units 1 to 17 pass only vibration components near the knocking frequency in the signal from the knock sensor 15, and a filter 20 generates a background level corresponding to no knocking. Output yEAf of G L detector 21 and filter 20
:1rlJtruL'Jt11M22,B (3 detected!
, a210) Increase the output NOOR by "1" [1] Compare the output of the amplifier 22 with the output of the amplifier 23 as a reference, and if the output of the amplifier 22 is larger The comparator 24 determines that knocking has occurred and outputs a knocking signal.
, and an electric current that generates a voltage that increases proportionally in accordance with the generation strength of the knock signal. The igniter 18 detects the rotational position of the rotor in synchronization with the crankshaft of the disc 1, the pickup coil 26, which determines the reference position 1N of 1 and 1 at the time of ignition, and the voltage conversion described above. It has an ignition control circuit 27 that advances or retards the ignition timing in proportion to the voltage level of the circuit 25, an amplifier 28, and a power transistor 29 that energizes or disconnects the ignition coil 19. Here, the output signal of the above altitude Han No. 16 is knock control]
- It is input to the voltage conversion circuit 25 connected to the unit 17. In the case of a flatland with an altitude of zero, a in Figure 3
A predetermined voltage such as ``a'' is outputted, and the igniter 18 is matched to perform advance angle control in the same manner as in the past according to this voltage level, and when knocking occurs, this a is used as a reference.
The angle is retarded by increasing voltage as shown in 7. Additionally, when the output signal of the altitude sensor 16 becomes high at high altitudes, the voltage level of the voltage conversion circuit 2 (i) is shifted to avoid shifting the reference point overall to the lower voltage side as indicated by the arrow in Fig. 3. With this configuration, on flat ground, the voltage conversion circuit 2 of the knock control unit 17 is
With the voltage 1 novel of the throttle valve 6 set to a high value, advance angle control similar to the conventional one is performed by the operation of the vacuum advance angle device 14 based on the negative pressure at ports 1 to 11 of the throttle valve 6. Then, when knocking occurs, the voltage of the voltage conversion circuit 25 becomes higher according to the intensity of the knock occurrence, so that the ignition control circuit 27 in the igniter 18 performs retard control.On the other hand, at high altitudes, the high altitude sensor 16 lowers the voltage. Conversion circuit 2
Since the voltage of 5 is shifted to be lower overall,
The ignition control circuit 27 of the igniter 18 shifts to the advance side. Therefore, in the vacuum advance device J14, the ignition time +v1, which is delayed due to the decrease in atmospheric pressure, is the igniter 18.
The ignition timing is offset by the advance effect of , and the ignition timing is set to the same level as on a flat ground. As is clear from the above, when the present invention is used, the ignition timing is set to the same level as on a flat land even at high altitudes, so it is possible to prevent a decrease in output and a deterioration of fuel efficiency due to high altitudes. It becomes possible. Knock control units 1 to 17 are used as countermeasures against knocking, and the igniter 18 is used as a countermeasure against high altitudes. ] Control operation is ensured and groove construction is also simplified.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing one embodiment of the apparatus according to the present invention, FIG. 2 is a block diagram of the main parts, and FIG. 3 is a diagram showing the operating state. 6... Throttle valve, 13... Distributor, 14... Vacuum advance device, 15... Knock sensor,
16... Takamaro Senryu, 17... Knock control unit, 18... Igniter. Patent applicant: Fuji Heavy Industries Co., Ltd. Agent: Patent attorney: Makoto Kobashi Ukiyo Patent attorney: Susumu Muratsuki

Claims (1)

[Claims] The ignition timing is controlled by operating the vacuum advance device using the boat negative pressure corresponding to the opening of the throttle valve, and the ignition timing is controlled at night and night by the output voltage of the knock control unit equipped with a knock sensor. An ignition timing control device characterized in that the output voltage of the knock control unit is changed by the output signal of the altitude sensor, and the ignition timing determined by the igniter is entirely shifted to the advance side at high altitudes. .