DE102021110201A1 - CONTROL UNIT - Google Patents

Abstract

Control device for controlling an ignition timing of an internal combustion engine installed in a vehicle, having a crank angle sensor, change degree determining means for determining, based on a detection result of the crank angle sensor, whether a change degree of a rotational speed of the internal combustion engine on a retard side is not lower than a predetermined change degree, and setting means for setting a fixed one Ignition mode or a calculated ignition mode in which the ignition point is advanced or retarded. The setting means sets the fixed ignition mode when the change degree determining means determines that the change degree is not lower than the predetermined change degree.

Description

BACKGROUND OF THE INVENTION

Field of invention

The present invention relates to an ignition control technique for an internal combustion engine.

Description of the prior art

As an ignition control for an internal combustion engine, a method is known for switching between a fixed ignition mode in which the ignition timing is fixed and a calculated ignition mode in which the ignition timing is advanced or retarded according to the operating state of the internal combustion engine. That Japanese Patent No. 2007-92581 discloses a method for switching the mode from the calculated ignition mode to the fixed ignition mode when the current value of the speed of an internal combustion engine is lower than a threshold value.

Even in a state in which the speed of the internal combustion engine is low, such as idling, the control of the ignition timing in the mode of the calculated ignition is advantageous for the control of the vehicle start or the later catalyst temperature. However, if the speed of the internal combustion engine drops abruptly, the execution of the calculated ignition is delayed and the ignition point can be advanced too far. This causes a torque of the internal combustion engine in the opposite direction of rotation.

SUMMARY OF THE INVENTION

It is an object of the present invention to suppress an excessive advance of an ignition timing when the speed of an internal combustion engine drops sharply.

The present invention relates to a control device according to claims 1 to 5.

Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the accompanying drawings).

Figure list

• [ 1 ] 1 Fig. 13 is a side view of a vehicle as an example of application of a control device according to the present invention;
• [ 2 ] 2 Fig. 3 is a block diagram of the control device according to an embodiment of the present invention;
• [ 3 ] 3A FIG. 13 is an explanatory view of a fixed ignition timing and a setting timing, and FIG 3B Fig. 13 is an explanatory view of a rotation speed in switching the ignition mode and the like;
• [ 4th ] 4th FIG. 13 shows a flowchart showing an example of a process derived from the FIG 2 control device shown is executed; and
• [ 5 ] 5 FIG. 13 shows a flowchart showing an example of a process derived from the FIG 2 control device shown is executed.

DESCRIPTION OF THE EMBODIMENTS

Embodiments are described in detail below with reference to the accompanying drawings. It should be noted that the following embodiments are not intended to limit the scope of the claimed invention, and that the invention does not include all combinations of the features described in the embodiments. Two or more of the multiple features described in the exemplary embodiments can optionally be combined. In addition, the same or similar configurations are provided with the same reference symbols, which is why a redundant description is dispensed with.

<Location of the vehicle>

1 Fig. 13 shows an embodiment of a vehicle to which a control device according to the present invention can be applied, and particularly shows a side view (right side view) of a vehicle 100 of the saddle type. As a vehicle 100 according to this embodiment, a motorcycle with a front wheel FW and a rear wheel RW is shown as an example. However, the present invention can be applied to another type of vehicle.

The vehicle 100 includes a vehicle body frame 101 , which forms the skeleton of the vehicle. A front steering section 102 is at the front end of the vehicle body frame 101 mounted, and a swing arm 103 is pivoted at the rear end. The front steering section 102 includes a pair of left and right front forks 102a that carry the front wheel FW, and a handlebar grip 102b attached to the upper sections of the pair of front forks 102a is appropriate.

A vehicle speed sensor 13th , which detects the rotation of the front wheel FW, is controlled by the front fork 102a carried. The vehicle speed sensor 13th may detect the rotational speed of the front wheel FW and, based on the detection result, the vehicle speed of the vehicle 100 to calculate.

A throttle 102c , which enables accelerator operation of a driver, is at the right end portion of the handlebar grip 102b intended. The front end of the swing arm 103 is pivotable on the vehicle body frame 101 stored, and the rear wheel RW is at the rear end of the swing arm 103 stored.

An internal combustion engine is located in an area between the front wheel FW and the rear wheel RW 106 and a gearbox 107 on the vehicle body frame 101 stored. The internal combustion engine 106 is a 4-stroke / DOHC / water-cooled engine with four parallel cylinders and comprises a crankcase, a cylinder block and a cylinder head. The internal combustion engine 106 sucks air through an intake duct 111 at. After combustion, an exhaust gas is generated from an exhaust duct 112 pushed out. The exhaust duct 112 includes an exhaust pipe 112a , which is connected to an exhaust port corresponding to each of the cylinders, a collecting portion 112b holding the exhaust pipes 112a merges, a three-way catalyst 112c and a muffler 112d . The performance of the internal combustion engine 106 is about the transmission 107 and a chain transmission mechanism (not shown) transmitted to the rear wheel RW.

Above the internal combustion engine 106 is a fuel tank 105 arranged, and at the rear of the fuel tank 105 is a seat 104 arranged on which the driver sits. Inside the fuel tank 105 is an air filter box 108 arranged that introduces outside air. An air filter (not shown) and an inlet duct 111 forming air funnel purple, are in the interior of the air filter box 108 arranged. The air filtered through the air filter can go through the air funnel 111a in the internal combustion engine 106 be initiated. At the bottom of the seat 104 is a control device 10 on the body frame 101 supported.

<Control device>

2 Fig. 3 is a block diagram of a control device 1 of the internal combustion engine 106 and particularly shows an arrangement for ignition control. The internal combustion engine 106 includes a crankshaft 106a which is connected to the pistons of cylinders # 1 to # 4 via connecting rods. The rotation of the internal combustion engine 106 is by a crank angle sensor 12th recorded.

In this embodiment, the crank angle sensor is 12th a non-contact magnetic sensor. On the crankshaft 106a is a rotor 12a attached, which goes together with the crankshaft 106a turns. On the outer peripheral surface of the rotor 12a a plurality of detection target portions (e.g., protrusions) are provided in the circumferential direction at a predetermined angular interval. The crank angle sensor 12th detects each detection target portion and outputs as a detection signal 12b outputs a pulse signal representing a pulse train for every predetermined amount of rotation. The number of pulses is the key figure for the phase or angle of the crankshaft 106a , and a time T between the pulses is the index of the speed of the internal combustion engine 106 .

Other sensors 14th For example, represent a sensor that detects a throttle opening, a sensor that detects suction pressure, a sensor that detects a cam angle, a water temperature sensor, and the like. An ignition device 11 includes a spark plug for each of the cylinders # 1 to # 4 and an electric circuit configured to supply high voltage to the spark plugs and generate a spark in the combustion chamber for each of cylinders # 1 to # 4 to ignite an air-fuel mixture.

The control unit 1 includes the control unit (ECU) 10 . The control unit 10 includes a processor implemented by a CPU, a storage unit, such as e.g. B. a semiconductor memory, an input / output interface to an external device and the like. The memory unit stores programs to be executed by the processor and data that are used by the processor for processing. Based on the detection results of the crank angle sensor 12th , the vehicle speed sensor 13th and the other sensors 14th controls the control unit 10 the igniter 11 .

<Ignition control mode and ignition timing>

According to this embodiment, the ignition timing mode can be selectively switched between a fixed ignition mode and a calculated ignition mode. In the "Fixed ignition" mode, the ignition point is fixed. 3A shows an example of the ignition timing (fixed ignition timing) in the "Fixed ignition" mode.

This in 3A The example shown assumes a case where the compression top dead center (TDC) of cylinder # 1 is the phase of the crankshaft 106a Is 0 ° and the fixed ignition timing of cylinder # 1 is set to a point in time before that. It should be noted that 3A Fig. 11 illustrates an example of the setting timing (switching timing) of the ignition control mode, which is set to a sufficient timing before TDC.

The calculated ignition mode is a mode in which the ignition timing depends on the operating state (the rotational speed, the throttle valve opening, the intake pressure, the water temperature, and the like) of the internal combustion engine 106 is brought forward or retarded compared to the fixed ignition point. For example, if the speed of the internal combustion engine 106 is high, the ignition timing is advanced compared with a case where the engine speed is low. During the cold period, the ignition point is retarded in order to increase the temperature of the three-way catalytic converter 112c to promote. In the calculated ignition mode, the ignition point becomes the operating state of the internal combustion engine in a map format 106 set accordingly and this information and the information of the fixed ignition point in the memory unit of the control unit 10 saved.

3B shows basic setting conditions of the ignition control modes. The abscissa represents the speed of the internal combustion engine 106 represents (the speed of the crankshaft 106a ), NEi is an idling speed, and NEs is an example of the switching speed of the ignition control mode. The idling speed NEi is a speed in the range from 1200 to 1500 rpm, for example. The shift speed NEs is z. B. set to a speed lower than the idle speed NEi. The time Ts denotes a time T between pulses at the shift speed NEs.

When the speed is low, the internal combustion engine is 106 unstable due to an unstable suction pressure and the like. Therefore, the fixed ignition mode is set. On the other hand, the calculated ignition mode has many advantages because it promotes heating in the cold period and at the time of starting the vehicle 100 Can achieve stability. Therefore, it is advantageous to decrease the shift speed NEs to a lower speed.

However, if the set speed of the calculated ignition mode goes into the low speed range, e.g. B. when the speed of the internal combustion engine 106 drops abruptly, as indicated by a dashed line D, the ignition point may be advanced too far. For example, an advanced ignition point, which is set at a high speed when starting by accelerating, is not sufficiently corrected in the corresponding direction when the speed is reduced by engaging the clutch, and this can affect the state of the internal combustion engine 106 too far advanced ignition timing can be set. Ignition at this ignition point causes the internal combustion engine to torque 106 in the opposite direction of rotation and leads to the engine stalling.

Therefore, in this embodiment, the fixed ignition timing is set in accordance with the degree of change on the retard side of the rotational speed. Since the fixed ignition timing is set immediately, the ignition timing can be prevented from being excessively advanced. A detailed control example is described below.

<Example of a controller>

4th Fig. 13 is a flowchart showing an example of execution of the ignition control performed by the control unit 10 is repeated periodically. In step S1 is based on the detection result of the crank angle sensor 12th determines whether the phase of the crankshaft 106a the setting time is (see 3A) . If it is determined that this is the adjustment time, the process goes to step S2 above. If it is determined that it is not the setting time, the process goes to step S4 above.

In step S2 the above-described ignition timing or the calculated ignition mode is set as the ignition control mode. Details will be described later. In step S3 the ignition timing is set for each cylinder. In the "Fixed ignition" operating mode, a fixed ignition point is set for each cylinder. In the calculated ignition mode, the ignition point for each cylinder is dependent on the operating state of the internal combustion engine 106 set.

In step S4 it is determined for each cylinder whether the in step S3 the set ignition point has arrived. When the ignition timing has come, the process goes to step S5 over to perform the ignition process. During the ignition process, the cylinder whose ignition timing has come is ignited. The process is now over.

5 is a flow chart that appears in step S2 shows an example of mode setting. In step S11 is based on the detection result of the crank angle sensor 12th determines whether the speed of the internal combustion engine 106 is equal to or lower than the shift speed NEs. In this embodiment the time T between the pulses is counted and compared with the time Ts ( 3B) . If there is a relationship given by the time T time Ts, it is determined whether the engine speed is 106 is equal to or lower than the shift speed NEs. Note that, in this process, for the information of the time T, a time Tn and a time Tn-1 from the previous process are stored in the storage unit.

If in step S12 based on the result of the determination in step S11 it is determined that the speed of the internal combustion engine 106 is equal to or lower than the shift speed NEs, the method goes to step S18 away. When it is found that the engine speed 106 the shift speed exceeds Nes, the procedure goes to step S13 above. In step S18 the fixed ignition mode is set and the process is ended.

In step S13 it is determined whether the vehicle speed is lower than a predetermined vehicle speed. The vehicle speed is determined based on the detection result of the vehicle speed sensor 13th calculated. The predetermined vehicle speed is set, for example, to a speed which is higher than the idling speed NEi (for example a speed in the range from 1200 to 2000 rpm). If the vehicle speed is lower than the predetermined vehicle speed, step S15 proceeded. If the vehicle speed is equal to or higher than the predetermined vehicle speed, the process goes to step S17 since the influence is small even with excessive pre-ignition. In step S17 the calculated ignition mode is set and the process is ended.

Als Schwellenwert für die Drehzahldifferenz wird z. B. eine Drehzahl im Bereich von 100 U/min bis 200 U/min eingestellt. In dieser Ausführungsform erfolgt die Bestimmung auf Basis der Zeit T zwischen den Impulsen durch $$\text{Tn}-\text{Tn}-1\ge \text{Schwellenwert f}\ddot{\text{u}}\text{r die Zeitdifferenz}$$

Der Schwellenwert für die Zeitdifferenz ist eine Zeit, die dem Schwellenwert für die Drehzahldifferenz entspricht.In step S15 is based on the detection result of the crank angle sensor 12th determines whether the degree of change in the engine speed 106 on the delay side is equal to or higher than a predetermined degree of change. This determination can be made by the speed of the internal combustion engine 106 be expressed by $$\begin{array}{l}\text{Speed in the previous sequence}-\text{Speed at current sequence}\\ \ge \text{Threshold f}\ddot{\text{u}}\text{r is the speed difference}\text{.}\end{array}$$

The threshold value for the speed difference is z. B. set a speed in the range of 100 rpm to 200 rpm. In this embodiment, the determination is made based on the time T between pulses $$\text{Tn}-\text{Tn}-1\ge \text{Threshold f}\ddot{\text{u}}\text{r is the time difference}$$

The threshold value for the time difference is a time corresponding to the threshold value for the speed difference.

If in step S16 as a result of the determination in step S15 it is determined that the degree of change is equal to or higher than the predetermined degree of change, the method goes to step S18 to set the fixed ignition mode. In this way, it can be avoided that a point in time that has been brought forward too far is set as the ignition point in time. If it is determined that the degree of change is lower than the predetermined degree of change, the procedure goes to step S17 to set the calculated ignition mode.

<Other Embodiments>

In the embodiment described above, the in 5 The mode setting process shown is the process using the vehicle speed as a criterion (steps S13 and S14 ). However, a process can be used where this is not done.

In the embodiment described above, the speed and the degree of change are evaluated based on the time T between the pulses. However, the time T between pulses can be the average of the times between three or more pulses. In addition, the speed can be determined by counting the duration of one revolution of the crankshaft 106a be calculated.

<Summary of Embodiment>

The embodiment described above discloses at least the following control device.

1. 1. A control device according to the embodiment described above is a control device ( 1 ) for controlling an ignition point of an internal combustion engine ( 106 ) in a vehicle ( 100 ) is installed, comprising:
   • a crank angle sensor ( 12th ), which is designed to rotate a crankshaft ( 106a ) of the internal combustion engine ( 106 ) capture;
   • Means of determining the degree of change ( 10 , S15 ) to determine, based on a detection result of a crank angle sensor ( 12th ), whether a degree of change in a speed of the internal combustion engine ( 106 ) is not lower than a predetermined degree of change on a delay side; and
   • Adjustment means ( 10 , S12 ) for setting a fixed ignition mode in which the ignition timing is fixed or a calculated ignition mode in which the ignition timing is advanced or retarded;
   • wherein the setting means sets the fixed ignition mode when the change degree determining means determines that the change degree is not lower than the predetermined change degree ( 10 , S16 , S18 ).

According to this embodiment, when the number of revolutions of the internal combustion engine drops abruptly, the ignition timing can be suppressed from being excessively advanced. As a result, the frequency of generating a torque in the reverse direction of rotation can be reduced.

• 2. In the embodiment described above, the control device further comprises speed determining means ( 10 , S11 ), based on the detection result of the crank angle sensor ( 12th ) to determine whether the speed of the internal combustion engine ( 106 ) is not higher than a predetermined speed (NEs), and wherein the setting means sets the fixed ignition mode when the speed determining means determines that the speed of the internal combustion engine is not higher than the predetermined speed ( 10 , S12 , S18 ), sets the calculated ignition mode when the speed determining means determines that the speed of the internal combustion engine is higher than the predetermined speed and the change degree determining means determines that the change degree is lower than the predetermined change degree ( 10 , S12 , S17 ), and sets the fixed ignition mode when the speed determining means determines that the speed of the internal combustion engine is higher than the predetermined speed, and the change degree determining means determines that the change degree is not lower than the predetermined change degree ( 10 , S16 , S18 ).

According to this embodiment, when the number of revolutions of the internal combustion engine drops abruptly, the ignition timing can be suppressed from being excessively advanced. As a result, the frequency of generating a torque in the reverse direction of rotation can be reduced. Even if the engine speed range in which the calculated ignition mode is set is expanded, excessive advancement can be suppressed.

• 3. In der oben beschriebenen Ausführungsform stellt das Einstellmittel den festen Zündmodus ein, wenn das Änderungsgradbestimmungsmittel feststellt, dass der Änderungsgrad nicht niedriger ist als der vorgegebene Änderungsgrad und eine Fahrzeuggeschwindigkeit des Fahrzeugs (100) niedriger ist als eine vorgegebene Fahrzeuggeschwindigkeit (10, S14, S16, S18).

Gemäß dieser Ausführungsform kann eine Situation, in der der Einfluss eines Drehmoments in Rückwärtsdrehrichtung groß ist, und eine Situation, in der der Einfluss klein ist, anhand der Fahrzeuggeschwindigkeit unterschieden werden, und der feste Zündmodus kann an einem Punkt hoher Wahrscheinlichkeit eingestellt werden.

• 3. In the embodiment described above, the setting means sets the fixed ignition mode when the change degree determining means determines that the change degree is not lower than the predetermined change degree and a vehicle speed of the vehicle ( 100 ) is lower than a given vehicle speed ( 10 , S14 , S16 , S18 ).

According to this embodiment, a situation in which the influence of a torque in the reverse rotation direction is large and a situation in which the influence is small can be discriminated based on the vehicle speed, and the fixed ignition mode can be set at a point of high probability.

• 4. In the embodiment described above, the predetermined speed is a speed within a range of an idle speed (NEi).

According to this embodiment, the ignition point can simply be set in the calculated ignition mode in the range of the idling speed. If, on the other hand, the speed drops suddenly, the fixed ignition mode is set. Excessive advancement can thus be suppressed.

• 5. In the embodiment described above, the crank angle sensor ( 12th ) a detection signal ( 12b ), the speed determining means determines based on a time (T) between the detection signals whether the speed of the engine is not more than the predetermined speed, and the change degree determining means determines whether the change degree based on the time (T) between the detection signals is not lower than the specified degree of change.

According to this embodiment, the rotational speed and the degree of change can be evaluated through a relatively simple process.

The invention is not restricted to the above embodiments, and various variations / changes are possible within the meaning of the invention.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• JP 2007092581 [0002]

Claims (5)

A control device (1) for controlling an ignition timing of an internal combustion engine (106) installed in a vehicle (100), comprising: a crank angle sensor (12) configured to detect a rotation of a crankshaft of the internal combustion engine; Change degree determining means (10) for determining, based on a detection result of the crank angle sensor (12), whether a change degree of a rotational speed of the internal combustion engine (106) on a deceleration side is not lower than a predetermined change degree; and setting means (10) for setting a fixed ignition mode in which the ignition timing is fixed or a calculated ignition mode in which the ignition timing is advanced or retarded; characterized in that the setting means sets the fixed ignition mode when the change degree determining means determines that the change degree is not lower than the predetermined change degree. Control device according to Claim 1 , further comprising speed determining means (10) for determining, based on the detection result of the crank angle sensor (12), whether the speed of the internal combustion engine (106) is not more than a predetermined speed (NEs), the setting means setting the fixed ignition mode when the speed determining means determines that the speed of the internal combustion engine is not higher than the predetermined speed; sets the calculated ignition mode when the speed determining means determines that the speed of the internal combustion engine is higher than the predetermined speed and the change degree determining means determines that the change degree is lower than the predetermined change degree; sets the fixed ignition mode when the speed determining means determines that the speed of the internal combustion engine is higher than the predetermined speed and the change degree determining means determines that the change degree is not lower than the predetermined change degree. Control device according to Claim 1 or 2 wherein the setting means (10) sets the fixed ignition mode when the change degree determining means determines that the change degree is not lower than the predetermined change degree and a vehicle speed of the vehicle (100) is lower than a predetermined vehicle speed. Control device according to Claim 2 , wherein the predetermined speed is a speed within a range of an idle speed (NEi). Control device according to Claim 2 , wherein the crank angle sensor (12) outputs a detection signal (12b) for each predetermined speed value of the crankshaft, the speed determining means determines on the basis of a time (T) between the detection signals whether the speed of the internal combustion engine is not higher than the predetermined speed, and that Change degree determining means determines whether the change degree is not lower than the predetermined change degree based on the time (T) between the detection signals.

Images