JPH051561A - Igniter of rotary piston engine - Google Patents

Abstract

PURPOSE:To reduce an ignition energy loss in a rotary piston engine equipped with three spark plugs. CONSTITUTION:Three spark plugs, consisting of an L plug 13, T plug 14 and a Far-T plug 15, are installed in a rotor housing 2 in order extending over the trailing side from the rotor rotative leading side. At the time of light load driving, these three spark plugs are all made so as to be ignited, and at the time of high load driving, merely two spark plugs, namely, the T plug 14 and the Far-T plug 15 are ignited, but at the time of medium load driving, the L plug 13 and the Far-T plug 15 merely are ignited, through which a reduction in ignition energy loss in a driving state unnecessary for three-piece ignition and an improvement in combustibility in each driving state are promoted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition device for a rotary piston engine, and more particularly to an ignition device provided with three ignition plugs.

[0002]

2. Description of the Related Art Conventionally, a general rotary piston engine has a rotor housing in the vicinity of a minor axis thereof, and the minor axis of the rotor housing is sandwiched between the rotor side and the leading side of the rotor rotation direction.
Spark plugs are provided in parallel at two positions on the ring side, and the ignition of the spark plugs burns the air-fuel mixture compressed in the working chamber.

Further, as an example of this rotary piston engine, as shown in Japanese Patent Application Laid-Open No. 63-309728, spark plugs are arranged at three positions, and the spark plugs are ignited at three positions in the working chamber. It is known that a flame is generated in. In the case where the spark plugs are arranged at three locations as described above, it is possible to improve the isochoricity by making the flame propagation speed uniform in the working chamber, especially during light load operation of the engine. It is possible to ensure stability.

[0004]

However, in the rotary piston engine having the three spark plugs as described above, the electric load is about 1.5 times that of the rotary piston engine having the two spark plugs. The fuel consumption is high and the fuel consumption is high because the energy loss increases as the electric load increases. Therefore, to improve the fuel efficiency of the rotary piston engine equipped with these three spark plugs,
Improvements have been required to improve its practicality.

The present invention has been made in view of this point, and in a rotary piston engine having three spark plugs, energy loss can be reduced while ensuring combustibility in the working chamber. The purpose is to get the configuration.

[0006]

In order to achieve the above-mentioned object, the present invention selects a plug to be ignited from three spark plugs to achieve good combustion only by igniting two spark plugs. In the operating state of the engine in which the above condition is obtained, one spark plug is not ignited to reduce energy loss. Specifically, as shown in FIG. 1, the invention according to claim 1 is the first, second, and third portions extending from the trailing side of the rotor housing 2 in the rotor rotation direction to the leading side. 3 spark plugs 13, 1
It is intended for the ignition device of the rotary piston engine 1 in which 4 and 15 are arranged. And engine 1
When the operating state of the engine 1 is in a high load state and the output of the operating state detecting means 20 for detecting the operating state of the second ignition plug 14 and the third ignition state is detected.
Spark plug selecting means 2 for igniting only the spark plug 15
1 and 1.

According to the second aspect of the present invention, the three first, second and third ignition plugs 13 are provided from the trailing side of the rotor housing 2 in the rotor rotation direction to the leading side. 1
It is intended for the ignition device of the rotary piston engine 1 in which 4 and 15 are arranged. And engine 1
When the operating state of the engine 1 is in the medium load state and the output of the operating state detecting means 20 detects the operating state detecting means 20 for detecting the operating state of
Spark plug selecting means 2 for igniting only the spark plug 15
1 and 1.

According to a third aspect of the present invention, the three first, second, and third ignition plugs 13 are provided from the trailing side of the rotor housing 2 in the rotor rotation direction to the leading side. 1
It is intended for the ignition device of the rotary piston engine 1 in which 4 and 15 are arranged. And engine 1
When the operating state of the engine 1 is in a high load state and the output of the operating state detecting means 20 for detecting the operating state of the second ignition plug 14 and the third ignition state is detected.
Only the spark plug 15 is ignited, only the first spark plug 13 and the third spark plug 15 are ignited in the medium load state, and each of the spark plugs 13, 1 is ignited in the light load state.
Spark plug selecting means 21 for igniting all four of four and fifteen
And is configured to include.

[0009]

With the above construction, the present invention provides the following actions. First, in the invention according to claim 1,
When the operating state detecting means 20 detects that the operating state of the engine 1 is a high load state, the spark plug selecting means 21.
Thus, only the second spark plug 14 and the third spark plug 15 are ignited. Since the flame propagation speed is high in this high load state, the flame is propagated to the reading side end zone even without igniting the first spark plug 13. In this way, by not igniting the first ignition plug 13, the electric load is reduced, the energy loss is reduced, and the fuel consumption of the engine 1 is reduced.

According to the second aspect of the invention, the operating state detecting means 20 indicates that the operating state of the engine 1 is a medium load state.
Is detected by the ignition plug selection means 21, the first
Only the spark plug 13 and the third spark plug 15 are ignited. In this medium load state, the flame propagation speed is slow, and since the periphery of the position where the second ignition plug 14 is disposed is the central portion of the combustion chamber, it is a region with good combustibility. Even without igniting 14, flame is propagated throughout the combustion chamber. In this way, by not igniting the second ignition plug 14, the electric load is reduced, the energy loss is reduced, and the fuel consumption of the engine 1 is reduced, as in the case of the operation according to the first aspect of the invention.

According to the third aspect of the present invention, when the operating state detecting means 20 detects that the operating state of the engine 1 is the high load state or the medium load state, the operation of the above-described first and second aspects of the invention is achieved. As described above, the combustibility of the entire combustion chamber can be secured by igniting only the two spark plugs. When the operating state detecting means 20 detects that the operating state of the engine 1 is a light load state, the ignition plug selecting means 21 causes the respective ignition plugs 13, 14, 15 to operate.
Ignite all three. Therefore, the combustibility can be ensured even in a light load state where the combustion stability deteriorates,
It is possible to improve the combustibility and reduce the energy loss according to each engine operating state.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a schematic overall configuration diagram of a two-rotor type rotary piston engine 1 according to the present embodiment.
The casing of the rotary piston engine 1 comprises two rotor housings 2 each having a trochoidal inner peripheral surface 2a.
And an intermediate housing 3 arranged between the two rotor housings 2 and a side housing (not shown) arranged on the opposite side of each rotor housing 2 from the intermediate housing 3. Made of Reference numeral 4 designates a substantially triangular rotor which makes a planetary rotational movement around an eccentric shaft 5 in the casing, and 6 designates the rotor.
The apex seal is attached to the top of the rotor 4 and is in sliding contact with the inner peripheral surface 2a of the rotor housing 2. These two rotors 4 rotate with a phase difference of 180 degrees with respect to the eccentric shaft 5. Then, the rotor 4 forms three working chambers I, II, and III in the casing.
With each rotation, the intake, compression, expansion, and exhaust strokes are performed in each of the working chambers I, II, and III. An intake port 7 opens on the inner peripheral surface 2a of the rotor housing 2 and is opened and closed at a predetermined timing by the rotor 4 in the intake stroke.
, 8 is an air cleaner, 9 is an air flow meter, 10 is a pair of throttle valves, 11 is an intake manifold, 1
Reference numeral 2 denotes an exhaust port which opens on the inner peripheral surface 2a of the rotor housing 2.

As one of the features of this embodiment, spark plugs 13, 14, 15 are provided at three locations on the rotor housing 2.
Is provided. This spark plug 13, 14, 15
Is the minor axis D of the rotor housing 2 as shown in FIG.
With one on the leading side and two on the trailing side, the working chamber (compression chamber) II as shown in FIGS. 2 and 3 has the smallest volume. The respective spark plugs 13, 14 and 15 are set in such arrangement positions as to face the working chamber II. That is, in such a rotor position, the L plug 13 as the first ignition plug located closest to the reading side is located at the center of the working chamber II, slightly toward the reading side. The T plug 14 as the second spark plug adjacent to the ring side is located slightly in the center of the working chamber II on the trailing side, and further Fa as the third spark plug located closest to the trailing side.
The r-T plug 15 is the end ring on the trailing side of the working chamber II.
It is set so that it is located at E.

During operation of the engine 1, the fuel pressure-fed from a fuel tank (not shown) is fed to a fuel injection valve 11a provided in the intake manifold 11.
In the intake manifold 11, a mixture is formed with the intake air sucked through the air cleaner 8, and the mixture is sucked into the working chamber (suction chamber) I. And then
When the volume of the suction chamber I is reduced by the rotation of the rotor 4 to become the compression chamber II and the mixture is brought to a high pressure state, a predetermined spark plug among the spark plugs 13, 14, 15 will be described later. Is selected, and the mixture is burned by the ignition of the spark plug.

Then, as described above, the rotary piston engine 1 selects the spark plugs 13, 14 and 15 to be ignited according to the operating state. Hereinafter, this control system will be described. CU in FIG. 2 is a control unit, and the intake air amount detected by the air flow meter 9, the throttle opening detected by a throttle opening sensor 16 provided in the throttle valve 10, the throttle Various detection signals such as the intake negative pressure detected by the boost sensor 17 provided immediately downstream of the valve 10 and the engine speed detected by the crank angle sensor 18 are transmitted. The ignition timing of each of the spark plugs 13, 14, 15 is controlled based on the signal. Further, a knocking detection signal from a knock sensor 19 provided in the rotor housing 2 is also transmitted to the control unit CU. Further, reference numeral 22 in FIG. 2 is a late closing on-off valve.

Next, the ignition timing control operation of the spark plug by the control unit CU will be described with reference to FIG.
A description will be given based on the chart and the map of FIG. Star
After that, first, in step S1, the various signals described above are read. Then, in step S2, it is determined based on the various signals read in step S1 whether the operating state of the engine 1 is the idle state or the light load state as the light load state in the present invention. Specifically, when the throttle opening detected by the throttle opening sensor 16 is in the fully closed state, it is determined to be in the idle state, and the engine speed detected by the crank angle sensor 18 On the other hand, when the suction negative pressure detected by the boost sensor 17 is low, it is determined that the engine 1 is in the light load state. Then, in step S2, the operating state of the engine 1 is the idle state or the light load state YES
In the case of (A area in FIG. 5), the process proceeds to step S3, and the current is supplied to each of the spark plugs 13, 14 and 15 in accordance with the ignition timing of each of the spark plugs 13, 14 and 15 so as to ignite all of them. To energize. If the operating state of the engine 1 is NO in neither the idle state nor the light load state in step S2, the process proceeds to step S4, and the operating state of the engine 1 is based on the various signals read in step S1. Is a medium load state. Specifically, step S2 described above.
The throttle opening sensor 1
6, crank angle sensor 18 and boost sensor 1
The determination is made based on the signal from 7. Then, in step S4, when the operating state of the engine 1 is the medium load state, YES (region B in FIG. 5)
In step S5, the Far-T plug 15 and the L plug 13 are selected, and a current is supplied to each of the spark plugs 13 and 15 in accordance with the ignition timing of each of the spark plugs 13 and 15 so that the two spark plugs are ignited. Turn on the power. If the operating state of the engine 1 is NO in the medium load state in the step S4, the process proceeds to step S6, and the step S6 is executed.
Based on the various signals read in 1, it is determined whether the operating state of the engine 1 is the fully open throttle state or the high load state as the high load state in the present invention. even here,
A determination is made in the same manner as the determination operation in steps S2 and S4 described above. And this step S
When the operating state of the engine 1 is the throttle fully open state or the high load state in 6 (YES in regions C and C'in FIG. 5), the process proceeds to step S7, and the Far-T plug 15 and the T plug 14 are selected. Then, in order to ignite these two spark plugs, a current is supplied to each of the spark plugs 14 and 15 in accordance with the ignition timing. Further, C in FIG. 5 is a high load operation region, and C ′
Is the supercharging area. If NO is determined in step S6, the routine is returned. In this way, in FIG. 4, the operating state detecting means 20 according to the present invention is constituted by steps S2, S4, S6, and step S
The spark plug selecting means 21 in the present invention is constituted by 3, S5 and S7. That is, as shown in Table 1 below, the spark plug is selected according to each operating state.

[0017]

[Table 1]

Next, the combustion operation in the combustion chamber II by the ignition of the selected spark plug, which is a feature of this embodiment, will be described.

First, when the operating state of the engine 1 is an idle state or a light load state, each spark plug 13, 1
When all 4 and 15 are ignited, the L plug 13 is ignited earliest to form a flame around the L plug 13, and thereafter,
The T plug 14 and the Far-T plug 15 are ignited. As a result, the tracing is performed from the reading side in the rotor rotation direction.
A unidirectional flame is propagated to the ring side, and this flame propagation is directional to improve the isochoric volume for good combustion and ensure stable combustion. .

Next, a case where the Far-T plug 15 and the L plug 13 are ignited when the engine 1 is operating under a medium load will be described. In this medium load state, since the amount of air-fuel mixture is small, the flame propagation speed in the working chamber (combustion chamber) II is slow, and the trailing end zone of the working chamber II is reduced.
Since it is difficult for the flame to propagate to the end zones E and the reading side end zones J, it is possible to propagate the flame to the respective end zones E and J by igniting the spark plugs 13 and 15 at both ends. I have to. In addition, the second spark plug 14
Since the vicinity of the arrangement position is a central portion of the combustion chamber, it is a region with good combustibility, and the flame can be propagated throughout the combustion chamber without igniting the second spark plug 14. As described above, instead of igniting all three spark plugs, the Far-T plug 15 and the L plug 13
By igniting only the book, energy loss due to electric load can be reduced. At the time of actual ignition, as described above, since the propagation speed of the flame is slow in this operating state, even if the ignition timing of the Far-T plug 15 is set early, combustion occurs before the top dead center of the rotor 4. Does not reach the peak (maximum pressure), which is why the Far-T plug 15
It is possible to ignite as soon as possible to secure the combustibility in the combustion chamber II. Further, in this way, the air-fuel mixture of the trailing end zone E is surely burned, and the occurrence of misfire in this portion is avoided. Is not present, the adverse effect on the exhaust system is prevented, and the emission property is improved.

The Far-T plug 1 is operated when the engine 1 is in the fully open throttle state or the high load state.
5 and the case where the T plug 14 is ignited. In this throttle fully open state or high load state, the amount of air-fuel mixture is large, so that the flame propagation speed in the working chamber (combustion chamber) II is high and L Without igniting the plug 13
The flame can be propagated to the reading side end zone J. Thus, in this case also, instead of igniting all three spark plugs, the Far-T plug 15 and T
By igniting only two of the plugs 14, the energy loss due to the electric load can be reduced. And, at the time of actual ignition, the reading side of the combustion chamber II is
As the space of the rotor 4 expands as it rotates, combustion is facilitated smoothly, and the flame generated by the ignition of the Far-T plug 15 and the T plug 14 is the flame described above. Is rapidly transmitted to the leading end zone J of the combustion chamber II, the flame is propagated throughout the combustion chamber, the combustibility is improved, and a high output can be obtained.
Further, in such a fully opened throttle state or a high load state, knocking may occur in the trailing side end zone E. In this case, the T plug 1
If the Far-T plug 15 is ignited before 4, the combustion of the air-fuel mixture in the trailing end zone E can be burned before the air-fuel mixture of the other parts. At the trailing end zone E, self-ignition of the air-fuel mixture, that is, knocking does not occur.

As described above, according to the configuration of this example,
By selecting and igniting only two spark plugs in an engine operating state in which all three spark plugs 13, 14 and 15 are ignited, in a medium load state, a throttle fully open state and a high load state, an electric load is obtained. Since it is possible to reduce energy loss due to, it is possible to achieve low fuel consumption of the engine and improve its practicality.

The ignition timing of each spark plug selected according to the operating state of the engine is not limited to the case of this example, but can be set arbitrarily.

[0024]

As described above, the present invention has the following effects. According to the first aspect of the present invention, when the engine is operating under a high load, only the second and third spark plugs are ignited without igniting the first spark plug to propagate the flame. Since the flame is propagated to the end zone on the reading side by utilizing the high speed, the electrical load is reduced while ensuring the combustibility, and the energy loss is reduced to reduce the engine It is possible to reduce fuel consumption.

According to the second aspect of the present invention, when the engine is operating in the medium load state, only the first spark plug and the third spark plug are ignited without igniting the second spark plug, Since the ignition timing of the third spark plug can be set earlier by utilizing the slow propagation speed of the flame, the electric load is reduced while the combustibility of the entire combustion chamber is ensured, and the energy loss is reduced. It is possible to achieve low fuel consumption.

According to the third aspect of the invention, in addition to the effects of the first and second aspects of the invention described above, all three ignition plugs are ignited in a light load state in which combustion stability deteriorates. Therefore, it is possible to secure the combustion stability in the light load state, and therefore it is possible to improve the combustibility and reduce the energy loss according to the operating state of each engine.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is a schematic overall view of a rotary piston engine.

FIG. 3 is an enlarged view of the vicinity of a position where an ignition plug is arranged.

FIG. 4 is a flow chart for explaining the operation of the control unit.
It is a chart.

FIG. 5 is a diagram showing an engine operating load region.

[Explanation of symbols]

1 rotary piston engine 2 rotor housing 4 rotors 13 L plug (first ignition plug) 14 T plug (second spark plug) 15 Far-T plug (3rd spark plug) 20 Operating state detection means 21 Spark plug selection means

Claims (3)

[Claims] 1. A rotary housing in which three spark plugs of first, second, and third are arranged from a trailing side of a rotor housing in a rotation direction of a rotor housing to a leading side thereof. An ignition device for a piston engine, comprising: an operating state detecting means for detecting an operating state of the engine; and an output of the operating state detecting means. When the operating state of the engine is a high load state, the second ignition plug and the second ignition plug 3. An ignition device for a rotary piston engine, comprising: an ignition plug selecting means for igniting only an ignition plug. 2. A rotary housing in which three spark plugs of first, second, and third are arranged from the trailing side in the rotor rotation direction of the rotor housing to the leading side. An ignition device for a piston engine, comprising: an operating state detecting means for detecting an operating state of the engine; and an output of the operating state detecting means, wherein when the operating state of the engine is a medium load state, the first spark plug and the first ignition plug 3. An ignition device for a rotary piston engine, comprising: an ignition plug selecting means for igniting only an ignition plug. 3. A rotary in which three spark plugs, namely, first, second, and third spark plugs are arranged from the trailing side of the rotor housing in the rotating direction of the rotor housing to the leading side. An ignition device for a piston engine, comprising: an operating state detecting means for detecting an operating state of the engine; and an output of the operating state detecting means. When the operating state of the engine is a high load state, the second ignition plug and the second ignition plug Ignition only 3 spark plugs,
And a spark plug selecting means for igniting only the first spark plug and the third spark plug in a medium load state and igniting all three of the spark plugs in a light load state. Ignition device for rotary piston engine.