JP2621271B2 - Ignition timing control device for internal combustion engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition timing control device for an internal combustion engine, and more particularly, to an ignition timing control device for an internal combustion engine in each of a plurality of operating regions according to properties of fuel supplied to the internal combustion engine. The present invention relates to an ignition timing control device for an internal combustion engine that can appropriately perform knocking control and improve engine operability by controlling the ignition timing of an internal combustion engine to a retard side by a predetermined amount based on a knocking detection value detected by a knocking sensor.

[Conventional technology]

As shown in FIG. 5, a knock sensor 86 is provided in the internal combustion engine 2 to prevent damage to the pistons and valves due to knocking when the internal combustion engine is driven, and a knock signal input from the knock sensor 86 causes the ignition coil 68 to operate. There is a type provided with a knocking control unit 88 for controlling the ignition timing of the ignition plug 28 to the ignition timing for suppressing knocking. As shown in FIG. 6, the knocking control unit 88 counts a knocking signal input from the knocking sensor 86 by a knocking counter, and when the counter value reaches a predetermined number, determines that knocking has occurred and retards the ignition timing by a predetermined amount. Side control.

Knocking should be controlled in this way, for example,
There are those disclosed in JP-A-62-118806 and JP-A-62-195465. The one disclosed in Japanese Patent Application Laid-Open No. Sho 62-118063 discloses a technique in which an ignition timing retard correction amount at the time of knocking is updated by learning control to obtain an appropriate learning retard amount, and the appropriate knocking control is performed. Is what you do. In addition,
Japanese Patent Application Laid-Open No. 62-195465 discloses that knocking is determined for each cylinder, and ignition timing is retarded for each cylinder to achieve appropriate knocking control.

[Problems to be solved by the invention]

Incidentally, as fuel supplied to the internal combustion engine, for example, gasoline fuel, there are regular gasoline (RON: 90 to 92) and high octane gasoline (RON: 98 to 100). Regular gasoline and high octane gasoline have different properties of fuel (octane number), and thus have different knocking occurrence states. Therefore, if the fuel supplied to the internal combustion engine is erroneously supplied, for example, if the regular gasoline is erroneously supplied where the high octane gasoline is to be supplied, knocking frequently occurs and the internal combustion engine may be damaged, Further, in an internal combustion engine that performs knocking control to suppress knocking, there is a disadvantage that operability is deteriorated because ignition timing is retarded by frequent knocking control.

[Object of the invention]

Therefore, an object of the present invention is to shift the ignition timing of the internal combustion engine to a predetermined amount on the retard side by a knocking detection value detected by a knocking sensor in each of a plurality of operating regions of the internal combustion engine according to the properties of fuel supplied to the internal combustion engine. An object of the present invention is to realize an ignition timing control device for an internal combustion engine that can perform knocking control appropriately and improve engine operability by performing control.

[Means for solving the problem]

In order to achieve this object, the present invention sets a knocking determination value corresponding to each of a plurality of operating regions divided according to an operating state of an internal combustion engine, and detects a knocking sensor in each of the plurality of operating regions. Comparing the knocking detection value with the knocking determination value corresponding to each of the plurality of operation regions to determine the property of the fuel supplied to the internal combustion engine, and according to the determined property of the fuel, Control means is provided for controlling the ignition timing of the internal combustion engine to a predetermined amount on the retard side according to a knocking detection value detected by the knocking sensor in each of the operation regions.

[Action]

According to the configuration of the present invention, the ignition timing of the internal combustion engine is determined by the control means based on the knocking detection value detected by the knocking sensor in each of the plurality of operation regions of the internal combustion engine according to the property of the fuel supplied to the internal combustion engine. Since the control is performed on the quantitative retard side, knocking control can be appropriately performed according to the properties of the fuel. Thus, even if fuel is erroneously supplied, there is no possibility that knocking frequently occurs to damage the internal combustion engine, and ignition timing is not retarded by frequent knocking control.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention. In FIG. 1, reference numeral 2 denotes an internal combustion engine, 4 denotes a supercharger constituted by a compressor 6 and an exhaust turbine 8, 10 denotes an intake passage, and 12 denotes an exhaust passage. An air cleaner 14 is provided in a first intake passage 10-1 on the upstream side of the compressor 6 of the supercharger 4, and a throttle body 18 having an intake throttle valve 16 is provided in a second intake passage 10-2 on the downstream side of the compressor 6. The third intake passage 10-3 formed at the bottom is in communication. This throttle body
A surge tank 20 is connected to 18 and the surge tank 20
The inside communicates with a fourth intake passage 10-4 formed in the intake manifold 22. The downstream end of the fourth intake passage 10-4 is connected to the intake valve 24.
Through the combustion chamber 26 of the internal combustion engine 2.

An ignition plug 28 is provided in the combustion chamber 26, and the upstream side of the first exhaust passage 12-1 communicates via an exhaust valve 30. An exhaust turbine 8 of the supercharger 4 is provided downstream of the first exhaust passage 12-1.
It communicates with the exhaust passage 12-2. A blow-by gas passage 32 communicating with the first intake passage 10-2 and the fourth intake passage 10-4 is connected to an upper portion of the internal combustion engine 2. A first fuel injection valve 34-1 is mounted on the intake manifold 22 so as to be directed toward the combustion chamber 26, and a second fuel injection valve 34- serving as a cold start injector facing the surge tank 20. 2 is installed. The fuel in the fuel tank 40 is pumped to the first and second fuel injection valves 34-1 and 34-2 by driving the fuel pump 36 to the fuel supply pipe 38. A fuel filter 42 is provided in the middle of the fuel supply pipe 38. A pressure adjusting passage 44 is provided in the fuel supply pipe 38 at one end thereof and communicates with the other end of the fuel tank 40 through the fuel tank 40. In the middle of this pressure adjusting passage 44, the first and second fuel injection valves 34-
A fuel pressure regulator 46 for regulating the pressure of the fuel acting on 1, 34-2 is provided.

The third intake passage 10-3 of the throttle body 18 and the fuel tank 40 are connected by a fuel vapor passage 48. In the evaporative fuel passage 48, a switching valve 50, a canister 52, and a two-way valve 54 are sequentially provided from the third intake passage 10-3 side. The third intake passage 10-3 and the surge tank
20 means an idle-up passage that bypasses the intake throttle valve 16.
It is communicated by 56. The idle-up passage 56 is provided with an idle-up control valve 58. The idle-up control valve 58 increases the amount of air by opening the idle-up passage 56 to increase the idle speed when the engine needs to be idle-up at the time of starting, at a high temperature, when the electric load increases, or the like. .

In the third intake passage 10-3, an advancing pressure introduction passage 66 for guiding pressure to a vacuum controller 64 attached to the distributor 62 of the ignition mechanism 60 is opened. The ignition mechanism 60 distributes and supplies the high voltage generated by the ignition coil 68 to the ignition plug 28 by the distributor 62, and causes the spark to fly. Fourth intake passage of the intake manifold 22
10-4, an EGR passage 70 opening at the start end to the first exhaust passage 12-1.
Is provided at the end opening. The EGR passage 70 has a fourth
EGR controlled to open and close to adjust the amount of EGR to intake passage 10-4
A valve 72 is provided.

The first and second fuel injection valves 34-1 and 34-2, the fuel pump 3
6. The switching valve 50, the idle-up control valve 58, and the ignition coil 68 are each connected to a control unit 74 as control means. The control unit 74 includes a water temperature sensor 78 for detecting a temperature of a cooling water in a cooling water passage 76 provided in the intake manifold 22 for heating the intake air, and an opening degree of the intake throttle valve 16 of the throttle body 18. A throttle sensor 80 for detecting a state,
The intake air temperature sensor 82 for detecting the intake air temperature provided in the first intake passage 10-1, and 0 ₂ sensor 84 for detecting the oxygen concentration in the exhaust gas provided in the second exhaust passage 12-2 is connected, also Knocking sensor provided in internal combustion engine 2 for detecting a knocking state
86 is connected via a knocking control unit 88. Reference numeral 90 denotes an automatic transmission control unit, 92 denotes a battery, 94 denotes a main switch, 96 denotes a thermofuse, 98 denotes an alarm relay, and 100 denotes a warning light.

The control unit 74 sets a knocking determination value corresponding to each of a plurality of divided operating regions according to the operating state of the internal combustion engine 2 by a knocking control unit 88, and a knocking sensor 86 in each of the plurality of operating regions. Is compared with the knocking determination value corresponding to each of the plurality of operating regions to determine the property of the fuel supplied to the internal combustion engine 2, and according to the determined property of the fuel, In each of the plurality of operating regions, the ignition timing of the internal combustion engine 2 is controlled to be retarded by a predetermined amount based on a knocking detection value detected by the knocking sensor 86.

That is, as shown in FIG. 3, according to the operating state of the internal combustion engine 2, the operating region is divided into a region for normal operation (1) and regions for acceleration operation and power traveling operation (2). In each of the regions (1) and (2), as shown in FIG. Knocking counter determination values are D,
F and the retard amount are set to H and C, respectively, and the timer determination time of the knocking counter value is set and controlled as shown in FIG.

Control starts (100), knocking occurs (101)
Then, it is determined (102) whether the area is (1) or (2).

In the case of the area (1), the knocking detection value A and the knocking determination value B are obtained by a signal input from the knocking sensor 86.
(103), and when A> B (104) is NO, (10)
Return to 1). If A> B (104) is YES, counting is started by the erroneous refueling determination timer (105), counter +1 (106) is performed, and the subsequent knocking counter coefficient value C and knocking counter determination value D are compared ( Ten
7) Then, C ≧ D (108) is determined, and if NO, the process returns to (101).

If C ≧ D (108) is YES, it is determined that fueling is erroneous (109), and it is determined whether the area is (1) or (2) (110).
In the region (1), the ignition timing is retarded (111) by a predetermined retardation amount H, and the ignition plug 6
Control is performed to make 8 fire. In addition, in the case of the region (2), control is performed to retard the ignition timing by a predetermined retard amount I (112).

On the other hand, if the knocking occurs (101) and the area (1) or (2) is determined (102), in the case of the area (2), knocking is detected by a signal input from the knocking sensor 86. The value A is compared with the knocking determination value E (113). If A> E (114) is NO, (10)
Return to 1). If A> E (114) is YES, counting by the erroneous refueling determination timer is started (115), and a counter + 1 (116) is performed, and the knocking counter coefficient value C and the knocking counter determination value F are compared thereafter ( 11
7) Then, C ≧ F (118) is determined. If NO, the process returns to (101).

When C ≧ F (118) is YES, it is determined that fueling is erroneous (109) and it is determined whether the area is (1) or (2) (110).
In the region (1), the ignition timing is retarded (111) by a predetermined retardation amount H, and the ignition plug 76 is used by the ignition plug 76.
Control is performed to make 8 fire. In addition, in the case of the region (2), control is performed to retard the ignition timing by a predetermined retard amount I (112).

As described above, the property of the fuel supplied to the internal combustion engine 2 is determined, and the ignition of the internal combustion engine 2 is performed based on the knocking detection value detected by the knocking sensor 86 in each of the plurality of operating regions of the internal combustion engine 2 according to the property of the fuel. Since the timing is controlled to the retard side by the predetermined amount, it is possible to perform control for appropriately suppressing knocking according to the properties of the fuel. For this reason, even if fuel is erroneously supplied, knocking frequently occurs and the internal combustion engine 2
And the ignition timing is not retarded by frequent knocking control, so that the operability of the engine can be improved.

〔The invention's effect〕

As described above, according to the present invention, the ignition timing of the internal combustion engine is determined by the control means based on the knocking detection value detected by the knocking sensor in each of the plurality of operation regions of the internal combustion engine according to the property of the fuel supplied to the internal combustion engine. Since the control is performed on the retard side by a predetermined amount, knocking control can be appropriately performed according to the properties of the fuel. For this reason, even if fuel is erroneously supplied, there is no possibility that knocking frequently occurs and damages the internal combustion engine, and there is no possibility that ignition timing is retarded by frequent knocking control. Can be improved.

[Brief description of the drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 is a schematic diagram of an ignition timing control device of an internal combustion engine, FIG. 2 is a flowchart for ignition timing control of the ignition timing control device of an internal combustion engine, and FIG.
FIG. 4 is a diagram showing an operating region divided according to the engine operating state based on the load and the engine speed. FIGS. 4 (a), (b) and (c) show the knocking determination value and the knocking in the regions (1) and (2), respectively. It is a figure which shows a counter value and a retard amount. 5 (a), 5 (b) and 5 (c) are timing charts of a knocking signal, a knocking counter, and a knocking control amount (retard amount), respectively, and FIG. 6 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 unit,
86 is a knocking sensor, 88 is a knocking control unit, and 90 is an automatic transmission control.

Claims (1)

(57) [Claims] A knocking determination value corresponding to each of a plurality of operating regions divided according to an operating state of an internal combustion engine is set, and a knocking detection value detected by a knocking sensor in each of the plurality of operating regions and the plurality of knocking determination values are determined. Comparing the knocking determination value corresponding to each of the operating regions to determine the property of the fuel supplied to the internal combustion engine. According to the determined property of the fuel, the knocking is performed in each of the plurality of operating regions. An ignition timing control device for an internal combustion engine, further comprising control means for controlling the ignition timing of the internal combustion engine to a predetermined amount on the retard side based on a knocking detection value detected by a sensor.