JPS593174A - Engine control device - Google Patents

Abstract

PURPOSE:To prevent occurrence of knocking caused by abnormal combustion by a method wherein an intake temperature is sensed and an ignition timing is controlled with a delayed angle in response to the intake air temperature. CONSTITUTION:During idling operation, an output signal A of a pressure sensor 6 which is turned on at a positive pressure shows OFF condition due to a negative intake pressure E. Since the compression of the intake air is not performed by a turbine 1, the intake air temperature is less than the predetermined value and an output signal B of the intake air temperature sensor 7 is also in OFF condition. Therefore, the air valve control circuit 8 is not operated and the air valve 9 feeds a negative pressure defined by both throttle pressure D and the intake air pressure E to a diaphragm device 10 as a pressure F and then the distributor 11 is controlled under its advanced ignition. Then, the turbine 1 is driven under its midium and high speed operations. When the intake air temperature becomes higher than the set value, the air valve 9 feeds a positive pressure defined by the pressures D and E to the above device 10 so as to perform the delayed ignition control.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine control device, and more particularly to an engine control device that prevents the occurrence of knocking.

In a reciprocating engine, there are ignition timing conditions to obtain maximum efficiency, and the ignition timing is controlled in accordance with the rotational speed so that optimal ignition can always be performed. The optimal ignition timing is just before abnormal combustion occurs in the engine and knocking occurs. This knocking phenomenon becomes more likely to occur as the intake air temperature increases and the compression ratio increases. For this reason, racing engines use intercoolers that lower intake air temperature to prevent knocking, and cars equipped with Tase chargers use knocking sensors to detect knocking. If knocking is detected, the ignition timing is retarded to prevent knocking.

However, lowering the intake air temperature in commercially available vehicles poses problems in terms of installation space and cost for the intercooler. In addition, in a configuration that uses a knock sensor to retard the ignition timing, the detection accuracy is low because the knock sensor must be installed in the engine part where there is a lot of vibration to detect knocking, and the knock sensor itself is This has the problem of being relatively expensive.

Therefore, an object of the present invention is to provide an engine control device that can reliably prevent knocking while having a simple configuration.

In order to achieve such an object, the present invention detects the intake air temperature and retards the ignition timing in accordance with the intake air temperature to prevent knocking and obtain maximum efficiency.

Hereinafter, an engine control device according to the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram showing an embodiment of an engine control device according to the present invention, and a case where the engine control device is applied to an engine equipped with a tase charger where knocking is particularly likely to occur will be described. In the figure, 1 is a compression turbine of a Tase charger that compresses air supplied through an air filter (not shown), and 2 is a carburetor, which passes compressed air supplied from the compression turbine 1 through a reduced diameter part. This generates a negative pressure, takes in fuel from the venturi pipe 3, mixes it with air, and supplies this fuel-mixed air to each cylinder of the engine via the intake manifold 4. Reference numeral 5 denotes a throttle valve provided in the carburetor 2, which, as is well known, is linked to an accelerator pedal (not shown). Reference numerals 6 and 7 denote a pressure sensor and an intake temperature sensor provided in the intake manifold 4, and the pressure sensor 6 is, for example, a silicon pressure sensor. In this case, the pressure sensor 5 generates an output signal A when the pressure in the intake manifold 4 reaches a positive pressure equal to or higher than the set value, and the intake air temperature sensor 7 detects that the intake air temperature after compression by the compression turbine of the Tase charger is at the set value. It is configured to detect this and generate an output signal B when it exceeds the threshold. Reference numeral 8 denotes an air/air valve control circuit which receives the output signal from the pressure sensor 6 and the output signal B from the intake air temperature sensor 7, and when the input signal A is on and the input signal B is off, the intake valve The lubricant control signal C is generated only when the intake air in the manifold 4 has a positive pressure equal to or higher than the set value and the intake air temperature is lower than the set value.

Reference numeral 9 denotes an air/air valve, which normally supplies a pressure F determined by the throttle pressure and manifold pressure E to the diaphragm 10, and when a valve control signal 0 is generated, the pressure is weakened by atmospheric pressure and the pressure is supplied to the diaphragm 10. Supply to 10. Reference numeral 11 denotes a distributor, and the ignition timing is adjusted by the diaphragm 10. When the pressure F applied to the diaphragm 10 is negative pressure, advance control is performed, and when the pressure F is positive pressure, the ignition timing is controlled. is controlled by a retarded angle, and its characteristics are shown in FIG. On the other hand, the relationship between throttle opening and intake manifold pressure E in the engine is as shown in Figure 3, where curve It shows the characteristics when rotating, and Z shows the advance angle when idling.

In the engine configured as described above, the turbine 1 does not pressurize the intake air during idling because the tarze charger device does not operate. Furthermore, during this idling period, the load is low and the opening degree of the throttle valve 5 is small, so both the 1-throttle pressure and the intake manifold pressure E are negative pressures. Therefore, the pressure sensor 6 does not generate the output signal A since the intake manifold pressure E is a negative pressure.

Furthermore, during idling, since the turbine 1 is not compressing the intake air, the intake air temperature is below the set value and the output signal B of the intake air temperature sensor 7 is also turned off. Therefore, the air valve control circuit 8 which receives the output signal from the pressure sensor 6 and the output signal B from the intake air temperature sensor 7 does not operate, and the knob control signal C is turned off. The air valve 9 supplies negative pressure determined by the throttle pressure and the intake manifold pressure E to the diaphragm 10 as a pressure F whenever the lube control signal 0 is turned off. In this way, when the negative pressure F is supplied to the diaphragm 10, the diaphragm 10
The distributor 11 has the characteristics shown in FIG.
Advance angle control is performed.

Next, when you depress the accelerator pedal and open the throttle knob 5, a large amount of air-fuel mixture is supplied to the engine, increasing the rotational speed, and the relationship between the throttle pressure and intake manifold pressure E is set. The diaphragm 10 is controlled by the output pressure F of the air valve 9.
IJ computer 11
Advance angle control is performed. When the engine speed exceeds the intercept point, the turbocharger works and the intake air is compressed by the turbine. Therefore, when the turbocharger is operating, the throttle pressure and intake manifold pressure E become positive pressures higher than the set values, and the compressed intake air temperature also rises higher than the set values, creating a state in which knocking is likely to occur. Become. In this way, when the intake manifold pressure and intake temperature rise, pressure sensor 6 and intake temperature sensor 7
Output signals A and B are generated from air, ?, respectively. is supplied to the loop overturning circuit 8. When the output signals A and B are supplied simultaneously, the air valve control circuit 8
No lubricant control signal O is generated. Therefore, x 7− /
The valve 9 supplies positive pressure determined by the throttle pressure D (positive pressure) and the intake manifold pressure Ifl (positive pressure) to the diaphragm IO, thereby retarding the distributor 11 to prevent the occurrence of knocking. do.

Next, when the intake pressure in one intake manifold is a positive pressure higher than the set value and the intake temperature is lower than the set value, the occurrence of knocking is reduced.

Therefore, when the air valve control circuit 8 detects that the output signal of the pressure sensor 6 is on and the output signal of the intake air temperature sensor 7 is off, it generates the air/air valve control signal C. When the air/lube control signal 0 is generated,
The air/air valve 9 has its atmospheric pressure (9a) opened and the positive output pressure F is weakened. Therefore, the pressure F supplied to the diaphragm 10 is weakened compared to when both the spun intake pressure and intake temperature are high, and the retard control 111i is accordingly reduced.

In this way, when the intake air temperature is low, knocking due to abnormal combustion is unlikely to occur even if the compression ratio is high to some extent. , engine efficiency is increased.

In the above embodiment, the diaphragm 72 is controlled using an air/air valve, but an air valve may also be used, and the ignition timing adjustment of the distributor may be of any configuration. .

As explained above, the engine side tilting device according to the present invention outputs the control pressure for ignition timing control in the relationship between the throttle pressure of the carburetor, which takes in the intake air compressed by the turbocharger, and the intake manifold pressure. A valve unit is installed to supply this anti-shaving pressure to the diaphragm to adjust the ignition timing of the distributor, and a pressure sensor installed in the intake manifold detects pressure above the set value and when the intake temperature is below the set value. In this case, the retard side mtt' is reduced by controlling the above-mentioned lubricant unit and weakening the control pressure to atmospheric pressure. Therefore, when the intake pressure is high and the intake temperature is low, the retardation control amount is prevented from becoming excessive, and the efficiency of the engine can be improved.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of an engine control device according to the present invention, Fig. 2 is a characteristic diagram showing the relationship between engine intake pressure and advance angle, and Fig. 3 is an engine throttle/rube opening. FIG. 9 is a characteristic diagram showing a relationship 9F between the intake manifold pressure and the intake manifold pressure. 1...Turbine, 2...Carburetor, 3...Venturi pipe, 4...Intake manifold, 5
...Throttle knob, 6...Pressure case +, 7
...Intake temperature sensor, 8...Air nozzle control 1
Circuit, 9...Air nozzle, 10...Diaphragm, 11...Distributor-0 Fig. 1

Claims (1)

[Claims] (1) In an engine having a carburetor that takes compressed intake air into the turbocharger, a valve unit that generates control pressure in relation to the throttle pressure of the carburetor and the inside of the intake manifold, and (2) A diaphragm that advances or retards the ignition timing in order to control the distributor according to the pressure in the f unit, and a diaphragm that controls the ignition timing to advance or retard it, and output when the pressure in the intake manifold exceeds a set value. The pressure sensor that generates air, the intake temperature sensor that generates an output when the temperature of the compressed intake air exceeds the set value, and the output of the pressure sensor and intake temperature sensor are input, and when the intake pressure exceeds the set value. and a valve unit control circuit that weakens the control pressure to atmospheric pressure by detecting a condition in which the intake air temperature is below a set value and controlling the valve unit. .