JPH01280679A - Ignition timing control device for internal combustion engine - Google Patents

Abstract

PURPOSE:To properly prevent the occurrence of knocking, by a method wherein, in a plurality of the running regions of an internal combustion engine, based on the nature of fuel fed to the internal combustion engine and a knocking detecting value, the ignition timing of the internal combustion engine is controlled to the delay angle side by a given amount. CONSTITUTION:An ignition coil 68 to feed a high voltage to an ignition plug 28 of an internal combustion engine 2 is controlled by a knocking control part 88 based on a detecting signal from a knocking sensor 86. In this case, a knocking control part 88 sets knocking decision values responding to a plurality of respective running regions. In a knocking region, a knocking detecting value is compared with a decision value to discriminate the nature of fuel fed to the internal combustion engine. According to the nature of fuel and based on a knocking detecting value, the ignition timing of the internal combustion engine is controlled in each running region to the delay angle side by a given amount.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an ignition timing control device for an internal combustion engine, and in particular to an ignition timing control device for an internal combustion engine in each of a plurality of operating ranges of the internal combustion engine depending on the properties of fuel supplied to the internal combustion engine. By controlling the ignition timing of the internal combustion engine to be retarded by a predetermined amount based on the knocking detection value detected by the knocking sensor, knocking control can be achieved appropriately and precisely, and the required ignition timing can be set to improve engine performance. The present invention relates to an ignition timing control device for an internal combustion engine that can improve engine operability.

[Conventional technology]

In order to prevent damage to pistons, valves, etc. due to knocking when the internal combustion engine is driven, a knocking sensor 86 is provided in the internal combustion engine 2 as shown in FIG. A knocking control unit 88 that controls the ignition timing of the spark plug 28 to an ignition timing that suppresses knocking.
There are some that have . As shown in FIG. 7, the knocking control unit 8B counts the knocking signal input from the knocking sensor 86 using a knocking counter, and when the counter value reaches a predetermined number, delays the ignition timing by a predetermined amount in order to suppress knocking. One control is placed on the corner side.

For example, to control knocking in this way,
JP-A-62-118063 and JP-A-62-19
There is one disclosed in Japanese Patent No. 5465. Japanese Unexamined Patent Publication No. 62-11
The technology disclosed in Japanese Patent No. 8063 updates the ignition timing retardation correction amount when knocking occurs through learning control to obtain an appropriate learning retardation amount, thereby achieving appropriate knocking control. In addition, the one disclosed in Japanese Patent Application Laid-open No. 195465/1983 determines the knocking state for each cylinder,
Appropriate knock control is achieved by retarding the ignition timing for each cylinder.

[Problem that the invention seeks to solve]

By the way, the fuel supplied to the internal combustion engine, for example, gasoline fuel, is regular gasoline (RON: 90 to 9
2) and high-octane gasoline (RON: 98-100)
There is. Regular gasoline and high-octane gasoline have different fuel properties (octane number), so the state of knocking is different between regular gasoline and high-octane gasoline. For this reason, if the wrong fuel is supplied to the internal combustion engine, for example, if regular gasoline is mistakenly supplied where high-octane gasoline should be supplied, knocking may occur frequently and damage the internal combustion engine. Further, in an internal combustion engine that performs knocking control to suppress knocking, the frequent knocking control causes the ignition timing to be retarded, resulting in a disadvantage that the engine's drivability is degraded.

[Purpose of the invention]

Therefore, an object of the present invention is to ignite the internal combustion engine based on the knocking detection value detected by the knocking sensor in each of a plurality of operating ranges divided by the load and rotation speed of the internal combustion engine according to the properties of the fuel supplied to the internal combustion engine. By controlling the timing to a predetermined amount of retardation, knocking control can be achieved appropriately and precisely, and the required ignition timing can be set, improving engine performance and engine drivability. The objective is to realize a timing control device.

[Means for solving problems]

In order to achieve this object, the present invention sets a knocking judgment value corresponding to each of a plurality of operating regions divided according to the load and rotation speed of the internal combustion engine, and sets a knocking judgment value corresponding to each of the plurality of operating regions. The property of the fuel supplied to the internal combustion engine is determined by comparing the knocking detection value to be detected with the knocking judgment value corresponding to each of the plurality of operating regions, and the property of the fuel supplied to the internal combustion engine is determined according to the determined property of the fuel. The present invention is characterized in that a control means is provided for controlling the ignition timing of the internal combustion engine to be retarded by a predetermined amount based on the knocking detection value detected by the knocking sensor in each of the operating ranges.

[Effect]

According to the configuration of the present invention, the knocking detection value detected by the knocking sensor in each of the plurality of operating regions divided by the load and rotation speed of the internal combustion engine according to the properties of the fuel supplied to the internal combustion engine is controlled by the control means. Since the ignition timing of the internal combustion engine is controlled to be retarded by a predetermined amount, knocking control can be performed appropriately depending on the properties of the fuel and finely depending on the operating state. As a result, even if fuel is incorrectly refilled, knocking does not occur frequently and there is no risk of damaging the internal combustion engine, and the ignition timing is not retarded due to frequent knocking control, so that the required ignition timing is maintained. Can be set.

〔Example〕

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

1 to 6 show embodiments of this invention. 1st
In the figure, 2 is an internal combustion engine, 4 is a supercharger constituted by a compressor 6 and an exhaust turbine 8, 10 is an intake passage, and 12 is an exhaust passage.

First intake passage 10- on the upstream side of the compressor 6 of the supercharger 4
1 is provided with an air cleaner 14, and a second intake passage 10-2 on the downstream side of the compressor 6 is provided with a third intake passage 1 formed in a throttle body 18 equipped with an intake throttle valve 16.
0-3 are communicating.

A surge tank 20 is connected to the throttle body 18, and the inside of the surge tank 20 communicates with a fourth intake passage 10-4 formed in an intake manifold 22. The downstream end of the fourth intake passage 10-4 communicates with the combustion chamber 26 of the internal combustion engine 2 via the intake valve 24.

A spark plug 28 is provided in the combustion chamber 26, and an exhaust valve 3
The upstream side of the first exhaust passage 12-1 communicates with each other via the exhaust passage 12-1. The exhaust turbine 8 of the supercharger 4 is provided downstream of the first exhaust passage 12-1.
The downstream side communicates with the second exhaust passage 12-2. Also,
A blow-by gas passage 32 is connected to the upper part of the internal combustion engine 2 and communicates with the first intake passage 10-2 and the fourth intake passage 10-4, respectively. The intake manifold 22 includes a first fuel injection valve 34 oriented toward the combustion chamber 26.
-1 is installed, and a second fuel injection valve 34-2, which is a cold start injector, is installed facing into the surge tank 20. The fuel in the fuel tank 40 is forced into the first and second fuel injection valves 34-1, 34-2 through the fuel supply pipe 38 by driving the fuel pump 36. A fuel filter 42 is interposed in the middle of the fuel supply pipe 38. Also, one end of the fuel supply pipe 38 communicates with the fuel tank 4 at the other end.
A pressure adjustment passage 44 that opens into the zero fuel is provided. In the middle of this pressure adjustment passage 44, the first and second
A fuel pressure regulator 46 is provided to adjust the pressure of fuel acting on the fuel injection valves 34-1, 34-2.

The third intake passage 10-3 of the throttle body 18 and the fuel tank 40 are communicated with each other through an evaporative fuel passage 48. In the vaporized fuel passage 48, a switching valve 50 and a canister 52 are sequentially installed from the third intake passage 10-3 side.
and a two-way valve 54 are provided. The third intake passage 10-3 and the inside of the surge tank 20 are connected to the intake throttle valve 16.
They are communicated by an idle amplifier path 56 that bypasses the. This idle up passage 56 is provided with an idle amplifier control valve 58. Idle amplifier control valve 5
8 increases the idle speed by opening the idle amplifier passage 56 to increase the amount of air and increase the number of idle revolutions when an idle amplifier is required at startup, at high temperatures, and when the electrical load increases.

Further, an advance pressure introduction passage 66 that introduces pressure to a vacuum controller 64 attached to the distributor 2 of the ignition mechanism 60 is opened in the third intake passage 10-3. The ignition mechanism 60 distributes and supplies the high voltage generated by the ignition coil 68 to the ignition plug 28 using the distributor 2 to cause the spark to fly. A first exhaust passage 12 is connected to the fourth intake passage 10-4 of the intake manifold 22.
The EGR passage 70 has a starting end opening at -1 and a terminal opening opening. This EGR passage 70 includes a fourth intake passage 10-
An EGR valve 72 is provided which is controlled to open and close in order to adjust the amount of EGR to 4.

The first and second fuel injection valves 34-1, 34-2, the fuel pump 36, the switching valve 50, the idle amplifier control valve 58, and the ignition coil 68 are controlled by a control section 74, which is a control means.
has been contacted. This control section 74 includes a cooling water passage 7 provided in the intake manifold 22 to warm intake air.
6, a throttle sensor 80 that detects the opening state of the intake throttle valve 16 of the throttle body 18, and a throttle sensor 80 that detects the temperature of the intake air provided in the first intake passage 10-1. The intake temperature sensor 82 is connected to an 02 sensor 84 provided in the second exhaust passage 12-2 that detects the oxygen concentration in the exhaust gas, and a knocking sensor 86 provided in the internal combustion engine 2 that detects the knocking state is connected. It is connected via a control section 88. The reference numeral 90 is an automatic transmission control section, 92 is a battery, 94 is a main switch, 96 is a thermofuse, 98 is an alarm relay, and 100 is a warning light.

The control unit 74 causes the knocking control unit 88 to set knocking determination values corresponding to each of the plurality of operating regions divided according to the load and rotational speed of the internal combustion engine 2, and to set the knocking determination value corresponding to each of the plurality of operating regions according to the load and rotation speed of the internal combustion engine 2, and to set the knocking determination value corresponding to each of the plurality of operating regions. 86 and corresponding to each of the plurality of operating regions.

The characteristics of the fuel supplied to the internal combustion engine 2 are determined by comparing the characteristics of the fuel supplied to the internal combustion engine 2, and the knocking detected by the knocking sensor 86 in each of the plurality of operating regions is determined based on the determined characteristics of the fuel. The ignition timing of the internal combustion engine 2 is controlled to be retarded by a predetermined amount based on the detected value.

That is, as shown in FIGS. 4 to 6, the loads L1 to L1 are applied along the load region dividing line between the region (1) during normal operation of the internal combustion engine 2 and the region (2) during acceleration and power running operation. L
r) and the rotational speed N1 to Nn.
,) 1-(1)n, (2)l to (2)n, respectively. Each area (1) 1 to (1) n, (2) 1 to (2) r
As shown in FIG.
Set the knocking counter judgment value for erroneous lubrication judgment to be compared with En and knocking counter count value C to Dn and Fn, respectively, set the retard amount to Hn and In, respectively, and set the timer judgment time of the knocking counter value, respectively. and control as shown in FIG.

Control is star 1-(100)L, knocking occurs (1
01) Then, first, general retard control (102) is performed to retard the ignition timing in accordance with the amount of knock. Then,
Determine whether the operating region is (1) or (2) (10
3) Do.

In the case of region (1), the number of rotations is determined (104,).

The knocking detection value A is determined by a signal manually inputted from the knocking sensor 86, and the operation range (1)1 to (1)n divided by the load 1 to Ln and the rotational speed N1 to Nn (
The knocking determination value Bn set for the region corresponding to the rotation speed in step 104) is compared (step 105).

If A>Bn (106) is NO, the process returns to (101). If A>Bn (106) is YES, the incorrect lubrication judgment timer starts running to 1 (107), performs counter +1-C (108), and then calculates the knocking counter count value C and the knocking counter judgment value Dn. (109) to determine C≧Dn(11,0),
If No (7), return to (101)).

If the above C≧Dn (110) is YES, it is determined that there is incorrect lubrication (111).L, the load L1~Ln and the rotation speed N1~
Multiple operating regions (1) 1 to (1) divided by Ln
The ignition timing is retarded (112) by a predetermined retard amount Hn in accordance with each of n, and the ignition coil 68 is controlled to cause the spark plug 28 to spark.

On the other hand, in determining (103) whether the operating region is (1) or (2), if the operating region is (2), the rotation speed is determined (113) t. The detected value A is compared (114) with the knocking judgment value En set for the region corresponding to the rotation speed in the judgment (113) of the plurality of divided operating regions (2)1 to (2)n. . A>En
If (115) is No, the process returns to (101). If A>En (115) is YES, start counting by the incorrect lubrication judgment timer (11611, perform counter l-1-C (117), and calculate the subsequent knocking counter count value C and knocking counter judgment value Fn. Compare (118)l, determine C≧Fn(119), and NO
In this case, the process returns to (101).

If the above C≧F (119) is YES, it is determined that there is incorrect lubrication (111) L, the load Ll-Ln and the rotation speed N1 to N
Multiple operating regions (2)1 to (2)n divided by n
The ignition timing is retarded (112) by a predetermined retard amount in in response to each of the above, and control is performed to cause the ignition coil 68 to cause the spark plug 28 to spark.

An example in which the above control is specifically applied to a three-cylinder internal combustion engine will be described with reference to FIG.

A knocking sensor 8 detects knocking in each cylinder #1 to #3 during one revolution of the crankshaft (not shown) of the internal combustion engine 2.
Detected by 6. Knocking at a certain level (BGL) or higher detected by the knocking sensor 86 is detected as a knocking detection value. For example, in the first rotation ■, the knocking detection value A of the first cylinder #1 is A-0, the knocking detection value A of the third cylinder #3 is A=3, and the knocking detection value A of the third cylinder #3 is A=3.
The knocking detection value A of 2 is A=2. Furthermore, the second
In the rotation ■, A=5, A-2, A=1, respectively.
So, in the third rotation ■, A=1 and A
=3, A=4.

From this, for example, if the knocking judgment value Bn in region (1) is set to Bn=2, the incorrect refueling judgment timer starts counting from the detection of the knocking detection value A-3 of the third cylinder #3 where A>Bn:YES. The knocking counter starts, counts the number of knocking occurrences within a certain period of time, and sets the counter -1 to the count value C of the knocking counter.

If the knocking counter judgment value Dn for the knocking counter count value C is, for example, Dn=3, then the knocking counter count value C is C=4 as shown in the figure.
If C≧Dn: YES, it is determined that erroneous refueling has occurred.

If it is determined that this erroneous refueling has occurred, control is performed to retard the engine by a predetermined retard amount Hn that falls within the region (3) as described above. Also,
In region (2), control is performed by retarding the angle by a predetermined retard amount In.

In this way, the properties of the fuel supplied to the internal combustion engine 2 are determined, and a plurality of operating ranges (1 to 1
)1 to (1)n, and each of (2)1 to (2)n,
Since the ignition timing of the internal combustion engine 2 is controlled to be retarded by a predetermined amount based on the knocking detection value detected by the knocking sensor 86, control to suppress knocking can be performed appropriately depending on the properties of the fuel and finely depending on the operating state. It can be carried out. Therefore, even if fuel is incorrectly refilled, there is no risk of knocking occurring frequently and damaging the internal combustion engine 2, and the ignition timing is not retarded due to frequent knocking control, so the required ignition timing Since it can be controlled to
Engine performance can be improved and engine drivability can be improved.

〔Effect of the invention〕

As described above, according to the present invention, the control means detects knocking detected by the knocking sensor in each of a plurality of operating regions divided by the load and rotational speed of the internal combustion engine according to the properties of the fuel supplied to the internal combustion engine. Since the ignition timing of the internal combustion engine is controlled to be retarded by a predetermined amount based on the value, knocking can be suppressed appropriately depending on the properties of the fuel and finely depending on the operating conditions. Therefore, even if fuel is incorrectly refilled, there is no risk of frequent knocking and damage to the internal combustion engine, and the ignition timing is not retarded due to frequent knocking control, so the required ignition timing is maintained. Since the engine speed can be set, engine performance and engine drivability can be improved.

[Brief explanation of the drawing]

1 to 6 show embodiments of the present invention, FIG. 1 is a schematic diagram of an ignition timing control device for an internal combustion engine, FIG. 2 is a flow chart for ignition timing control of the ignition timing control device for an internal combustion engine, and FIG.
The figure is a timing chart, Figure 4 is a diagram showing operating ranges divided into multiple parts according to the load and rotational speed of the internal combustion engine, and Figure 5
The figure shows the values corresponding to the load and the number of revolutions, Figure 6 (a
), (b), and (c) are diagrams showing knocking determination values, knocking center determination values, and retard amounts in regions (1) and (2), respectively. Figure 7 (a), (b), and (C) show the knocking signal, knocking counter, and knocking control amount (retard amount), respectively.
FIG. 8 is a schematic explanatory diagram of knocking control of the internal combustion engine. In the figure, 2 is an internal combustion engine, 10 is an intake passage, 12 is an exhaust passage, 16 is an intake throttle valve, 26 is a combustion chamber, 28 is a spark plug, 60 is an ignition mechanism, 62 is a distributor,
64 is a vacuum controller, 68 is an ignition coil, 74 is a control section, 86 is a knocking sensor, 88 is a knocking unit, and 90 is an automatic transmission control.

Claims (1)

[Claims] 1. Set a knocking judgment value corresponding to each of a plurality of operating regions divided according to the load and rotation speed of the internal combustion engine, and compare the knocking detection value detected by the knocking sensor in each of the plurality of operating regions with the plurality of operating regions. The properties of the fuel supplied to the internal combustion engine are determined by comparing the knocking judgment values corresponding to each of the regions, and the knocking sensor is adjusted in each of the plurality of operating regions according to the determined properties of the fuel. An ignition timing control device for an internal combustion engine, comprising a control means for controlling the ignition timing of the internal combustion engine to be retarded by a predetermined amount based on a detected knocking value.