JPH0810229B2 - How to determine the engine rotation status - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for determining a rotational state of a rotating body of an engine.

BACKGROUND ART An apparatus for determining a rotation reference position of a rotating body is disclosed in, for example, US Pat. No. 4,553,426.
In the apparatus described in the specification, a detector such as a magnetic projection is provided at equal angular intervals except for some missing portions in the rotation direction of the rotating body, and a predetermined level of output is provided each time the detector passes in the vicinity. The detection element that emits a signal is placed near the rotation locus of the detected element, the count value of the counter is incremented for each output generated by the detection element, and the counter value is reset when the detection element detects a missing part of the detected element. In other words, it is possible to determine whether or not the count value of the counter is a count value to be dealt with when the detecting element detects the missing part of the detected element, so that an accurate rotation reference position of the rotating body can be grasped. It is configured.

However, in the above-mentioned device, it was not possible to determine the rotation direction of the rotating body, that is, the forward rotation or the reverse rotation.

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned circumstances, the present invention aims to provide a rotation state determination method of a rotating body capable of determining whether the rotation state of the engine including the rotation direction of the engine is normal or abnormal. I am trying.

In the method for determining the rotational state at the time of starting the engine according to the present invention, at least two detected portions are provided at predetermined angular intervals in the rotation direction of the rotating body that responds to engine rotation, and the detected portions are provided at the predetermined intervals. Is provided in the vicinity of the rotational locus of the detected part, which generates an output of a predetermined level each time when the sensor passes the vicinity, and the stage count value is added by the unit number every time the output of at least one of the detectors is generated. Or, by subtracting, comparing both output levels of the sensing element and the current output level of the sensing element that should correspond to the current value of the stage count value, and when the corresponding relations do not match, It is configured to determine that the rotation state is abnormal.

Examples Hereinafter, examples in which the present invention is applied to an ignition device for an internal combustion engine will be described with reference to the accompanying drawings.

As shown in FIG. 1, in this embodiment, a magnetic protrusion is attached to a crankshaft of a two-cycle engine (not shown), and a rotating body 10 that rotates in the clockwise direction together with the crankshaft serves as a detected portion. 12a, 12b, 12c and 12d are formed. The arrangement of the magnetic protrusions is, for example, 45 °, 135 °, 180 ° clockwise with respect to the center of the rotating body 10 starting from 12a.
12b, 12c, and 12d are provided at the respective positions. The magnetic protrusion 12 is a pickup 13 with a built-in magnetic coil.
The pickups 13a and 13b are close to the rotation track of the magnetic protrusion 2 and are detected by a and 13b, and
They are arranged at an angle of 90 ° with respect to the center of the rotating body 1. The positions where the magnetic protrusions 12b and 12c face the pickups 13a and 13b respectively correspond to the compression top dead center of the first cylinder of the engine.

The pulse signal generated by the pickups 13a and 13b upon detecting the magnetic protrusion 12 is an amplifier 15 that also functions as a waveform shaper.
It is input to the control circuit 16 via a and 15b. The control circuit 16 receives input signals P1, INT1 and P2, INT2 for receiving the pulse signal.
And outputs an ignition command signal from the output ports P3 and P4 after calculation processing such as determining an ignition timing described later according to the input pulse signal. This ignition command signal is supplied to the ignition units 18a, 18b via the amplifiers 17a, 17b. The ignition units 18a and 18b perform ignition in response to the supplied ignition command signal. Input ports INT1 and IN
T2 is an input port that accepts a pulse signal only as an interrupt signal.

In the device shown in FIG. 1, during engine operation,
In accordance with the rotation of the rotating body 10, the pickup 13a outputs the detection pulse signal shown in FIG. 2 (A), and similarly the pickup 13b outputs the detection pulse signal shown in FIG. 2 (B).

These detection pulse signals are input to the input ports P1, INT1 and P2, INT2 of the control circuit 16 via the amplifiers 15a, 15b, respectively. FIG. 2 (C) shows pulse signals input to the input ports P1 and INT1, and FIG. 2 (D) shows the input port P2.
And the pulse signal input to INT2.

Of the pulse signals shown in FIGS. 2C and 2D, the pulse signals Pa ₁ and Pb _{1 that} are input at the same time are the rotor 10
Is a set of signals used for the rotation reference position determination, and other pulse signals are pulse signals used as rotation angle information of the rotating body 10.

The control circuit 16 is composed of, for example, a microcomputer including a CPU, a ROM, and a RAM, and performs an arithmetic operation according to a main routine or an interrupt subroutine described later.

3 to 10 are flowcharts showing a main routine and a subroutine executed by the control circuit 16.

First, when the power is turned on, as shown in FIG.
In the control circuit 16, the starting subroutine is sequentially executed for each step according to the fixed-cycle clock pulse.
Initialization is performed at the same time when the power is turned on, and INT1 interrupt and INT2 interrupt described later are prohibited (step S ₁ ). Then pc
It clears the PC buffer for temporarily storing the value (step S _2). The PC value displays the signal level input to the input ports P1 and P2 in 2 bits. The upper bit stores the signal level input to the input port P1 and the lower bit stores the input port. It stores the signal level input to P2, and both bits display 1 when the input signal level of each input port is higher than a predetermined level, and 0 when it is lower than the predetermined level. ing. After the PC buffer is cleared, create a PC value from the input signal levels of input ports P1 and P2 and
Value is the captured (Step S _3), wait for the PC value is a value other than 00, i.e., wait for the PC value is 11, 10 or 01 (step S _4). When the rotating body 10 PC value rotates becomes a value other than 00, and stores the PC value PC buffer (Step S _5). Then, a new PC value is imported (step
S ₆ ), wait until this PC value becomes 00 (step S ₇ ),
After the PC value reaches 00, import a new PC value (step
S ₈ ), wait until this PC value becomes a value other than 00 (step S ₉ ), and if this PC value becomes a value other than 00,
PC value is the determination of whether or not 11 (step S _10).
Here, if the PC value is 11, it is determined that the rotating body is at the rotation reference position corresponding to the compression top dead center of the first cylinder of the engine. Then stored in the PC buffer
PCb value forms a determination of whether or not 01 (step S _11).
By this determination, it is determined whether or not the rotation of the rotating body 10 is in the normal state. That is, in this embodiment, when the rotating body is in a normal rotating state, as is apparent from FIG. 2A, there is a state where PC = 00 before the reference position (PC = 11), and further before that. Since there is a state where PC = 01, and this state of PC = 1 has to be stored in the PC buffer in step S ₅ , the reference position (PC =
If the value (PCb) stored in the PC buffer when 11) is determined is the specified value (0,1), it is in the normal rotation state, and if it is other than this specified value (0,1), the rotation is reversed. It is an abnormal rotation state such as. In addition, when the normal rotation direction of the rotating body 10 is the counterclockwise direction in FIG.
It is clear that it will be (1,0). If in step S ₁₁ is confirmed to be the rotational state of the rotating body 10 to reset the stage count value to 1 (step S _12), no ignition of the first cylinder by outputting an ignition command signal from the output port P3 (Step S ₁₃ ), the prohibition of INT1 interrupt and INT2 interrupt is released (step S ₁₄ ), and the routine proceeds to execution of the main routine shown in FIG.

In step S _10, if not a PC = 11 is
New PC value is taken (Step S _15), the PC value is 00
Is determined (step S ₁₆ ). PC value is 0
If it is not 0, this PC value is temporarily stored in the A buffer (step S ₁₇ ), the process returns to step S ₁₀ and waits until the PC value becomes 00 (step S ₁₆ ). Transfer the PC value stored in the PC buffer (step S _18), returns to step S _8. Thus, in step S ₁₀ , PC = 11
If step S ₁₅ to step S ₁₈ are not obtained, the pulse signals Pa ₁ and Pb ₁ that should originally be generated to display the reference position at the same time do not occur at the same time due to manufacturing error, and the 2B As shown in the figure, even when there is a time lag, the rotation reference position of the rotating body 10, that is, the compression top dead center of the first cylinder can be reliably determined, and the rotational state of the rotating body can be accurately determined. You can do it.

The main routine shown in FIG. 4 determines the ignition timing T _IG based on a measured value T _S measured in an INT1 interrupt subroutine or an INT2 interrupt subroutine, which will be described later, based on a map stored in advance.

Fig. 5 shows a flowchart of the INT1 interrupt subroutine and the ITN2 interrupt subroutine. These interrupt subroutines are executed by interrupting the main routine when a signal pulse of a predetermined level or higher is input to the input port INT1 or INT2. As shown, input port INT1 or
When interrupting the main routine pulse signal is input to INT2, duration (measurement value) which took up current pulse signal input from the previous pulse signal input T _S is measured (steps S _20). Then, run the stage count subroutine shown in FIG. 6 (step S _21). The stage count subroutine is the count value S of the stage counter.
The unit number is incremented by 1 (step S ₂₂ ), and it is determined whether the count value S is 8 or more (step S ₂₃ ). If the count value S is 8 or more, the count value S is This is a subroutine for resetting to 1 (step S ₂₄ ). After the stage count subroutine is executed, it is determined whether or not the stage count value S is equal to 7 (step S ₂₅ ). If the count value S is not 7 here, the count value S is further set to 1. equal whether is determined (step S _26). The count value is whether the value the count value S is equivalent to the ignition stage determination is made if neither 1 (step S _27). Second A
In FIG. 6E, the change in the stage count value S is shown.

In the present embodiment, when the count value S becomes 1, the first cylinder is at the compression top dead center and the second cylinder has the count value S.
When it becomes 3, it is formed so as to become the compression top dead center. That is, the compression top dead center of the second cylinder lags the compression top dead center of the first cylinder by 90 ° in crank angle. The ignition stage in this case can be S = 6 for the first cylinder and S = 1 for the second cylinder, for example. In this way, if S = 6 and S = 1 are set as the ignition stages of the first cylinder and the second cylinder, respectively, the ignition stage is determined at 90 ° before the top dead center of each cylinder.

If it is determined that the stage count value S is equal ignition stage 6 or 1 in step S _27, the ignition process (step ₂₈₎ is performed. In the ignition process, the ignition timing T _IG obtained in the main routine is set as the count value t of the down counter, and the ignition command signal is output after waiting for the count value t of the down counter to reach zero or fall below zero. First output from P4
This is the process of igniting the cylinder or the second cylinder.

After the ignition processing is finished, it is judged whether or not the stage count value S is equal to 7 (step S ₂₉ ). When the count value S is equal to 7, the pulse signal input of the input port INT2 is set to INT2.
Prohibiting acceptance as an interrupt signal (step S
₃₀ ). If S = 7 in step S ₂₉ , it is further determined whether or not the count value S is equal to 1 (step S ₃₁ ). If the count value S is equal to 1, in step S ₃₀ . Input port INT2 whose reception is prohibited
The acceptance of the pulse signal input of as an INT2 interrupt signal is permitted (step _S32 ).

In this way, the INT2 interrupt is prohibited only when the count value S of the stage counter is 7, so that the pulse signals Pa ₁ and Pb are input to the input ports INT and INT2 as shown in FIG. 2B when the reference position is determined. ₁ is input with a time shift, and INT1 interrupt and I
It is possible to prevent duplicate execution of NT2 interrupt.

In step S _25, new captures PC value if the stage count value S was equal to 7 (step S
₃₃ ), and it is determined whether or not the PC value is 01 (step _S34 ). In the present embodiment, since the PC value to which the rotation of the rotating body 10 is taken in step S ₃₃ if normal is 01, the rotation of the rotary member 10 when the PC = 01 in step S ₃₄ is If the PC value is determined to be normal and the PC value is other than 01, it is determined that the rotating state of the rotating body is an abnormal state such as reverse rotation. In step S _34, when the rotation of the rotating body 10 is determined to be abnormal, stop the ignition process and the like to stop the down counter even if the ignition process in step S ₂₈ is started is allowed, so as not to perform the ignition (step S _35), returns to the starting subroutine shown in FIG. 3 (step S _36).

Further, in step S _26, the stage count value S
If is equal to 1, a new PC value is fetched (step S ₃₇ ), and it is not judged whether this PC value is 11 (step S ₃₈ ). The value is 0
No determination is made as to whether or not it is 0 (step _S39 ), and the PC value is 00.
If not, wait until the PC value reaches 11 (step
S ₃₈ ). In this embodiment, when the stage count value S is 1, the PC value should be 11 as shown in FIG. 2A. Therefore, when PC = 11 is determined, the PC rotation is determined to be normal, and the rotation reference position of the rotator is proceed to step S ₂₇ is simultaneously confirmed.
However, as shown in FIG. 2B, when the stage count value is 1, the pulse signals Pa ₁ and Pb ₁ may be input with a time lag, and the PC value may be PC while it is not 00. There is a possibility that the value will be 11, so we are waiting for the PC value to be 11. PC = 11 in step S ₃₈
If PC = 00 in step S ₃₉ , it means that the PC value that cannot be obtained when the stage count value S is 1 is taken in, and the rotation of the rotating body is abnormal. it is determined that there the sub-routine proceeds to step S _35.

As described above, when the stage count value S is 7 and 1 respectively, it corresponds to each count value.
It is possible to accurately determine the rotation direction of the rotating body by performing composite determination of whether or not the PC value is obtained.

FIG. 7 shows the INT1 interrupt subroutine shown in FIG.
Shows the INT1 and INT2 interrupt subroutines that are compatible with the INT2 interrupt subroutine. The same steps as those in the interrupt subroutine shown in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted. The interrupt subroutine shown in FIG.
Similar to the interrupt subroutine shown, input port INT1
Alternatively, it is executed by interrupting the main routine when a signal pulse of a predetermined level or higher is input to INT2. When interrupting the main routine by the input, after finishing the step S _20, S _21, captures the PC value (step S _40). Then
The stage count value S is determined (steps S ₄₁ , S
₄₂ , S ₄₃ , S ₄₅ , S ₄₆ , S ₄₇ ), and it is determined whether or not the PC value to be captured in the determined stage count value is captured in step S ₄₀ (step S ₄₈ , S ₄₉ , S ₅₀ , S
₅₁ , S ₅₂ , S ₅₃ , S ₅₄ ). In this way, it is determined whether the rotation state of the rotating body is normal or abnormal by determining whether or not the PC value that should correspond to the current stage count value is taken in. By doing
The rotation direction of the rotating body can be accurately determined. If the PC value that should correspond to the current stage count value S has been fetched, it is determined that the rotation of the rotating body 10 is normal, and the process proceeds to step S ₂₇ and subsequent steps, and vice versa. If the PC value that should correspond to is not taken in, the process proceeds to step _S36 and subsequent steps.

FIG. 8 shows a starting subroutine compatible with the starting subroutine shown in FIG. The same steps as those in the starting subroutine shown in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted.

When the power is turned on, the start-up subroutine shown in FIG. 8 is executed according to the fixed-cycle clock pulse, and INT1
Prohibit interrupts and INT2 interrupt (Step S _1), captures the PC value (step S _55), and determine the rotation reference position of the rotator waiting for the PC value is 11 (step S ₅₆₎ Then, the ignition command signal is output from the output port P3 to ignite the first cylinder (step _S57 ). Then, the PC standby subroutine shown in FIG. 9 is executed (step S ₅₈ ).

The PC standby subroutine fetches the PC value (step S
₆₀ ), wait for this PC value to be 00, then (step
S ₆₁ ), and also take in the PC value (step S ₆₂ ).
This is a subroutine for waiting for a value other than 00 (step S ₆₃ ).

By executing the PC standby subroutine, it is possible to prevent the PC value from once being waited until the PC value becomes 00, and to take in the PC value in duplicate from the same pulse signal.

Then, PC values captured in step S ₆₂ of PC standby subroutine discriminates whether or not 10 (step
S ₆₄ ). In this embodiment, the PC value obtained by the pulse signal input after the PC value changes from 11 to 00 should be 10. Therefore, if PC = 10 in step S ₆₄ , it is determined to be abnormal and step S Return to ₅₅ . After the rotation of the rotating body is determined to be normal in step S _64, to run the PC standby subroutine again (step S _65), whether PC values captured in step S ₆₂ of PC standby subroutine is 01 Is determined (step S ₆₆ ), and if the PC value is 01, it is determined that the rotation of the rotating body is normal. At this time, the second
Since the cylinder has reached the compression top dead center, the ignition command signal is output from the output port P4 to ignite the second cylinder (step _S67 ), and the count value S of the stage counter is set to 3 (step _S67 ). S _68), to allow the INT1 and INT2 interrupt (step S _14), the process proceeds to the main routine.

By configuring the startup routine in this way,
By monitoring the input state of the pulse signal after the ignition of the first cylinder, it is possible to determine an abnormality in the rotating state of the rotating body, etc., and it is possible to prevent the ignition of the second cylinder in that case.

FIG. 10 shows an interrupt subroutine compatible with the interrupt subroutines shown in FIGS. 5 and 7. The same steps as those in the interrupt subroutine shown in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted.

The interrupt subroutine shown in FIG. 10 is shown in FIGS.
Similar to the interrupt subroutine shown, input port INT1
Alternatively, when a signal pulse of a predetermined level or higher is input to INT2, the main routine is interrupted and executed. When interrupting the main routine by the input, step S _20, after performing the S _21, the measurement value measured in step S ₂₀ T _S
Is _compared with the value T _SL corresponding to the engine idle speed (step S ₇₀ ). Where the measured value T _S is T _SL
Greater than is determined that the rotational speed of the engine is lower than the idle rotation proceeds to step S _71. In step _S71 , it is determined whether or not the stage count value S is equal to 1, and if the count value S is equal to 1, the PC value is taken in (step _S72 ), and the PC value corresponding to the count value S, that is, waiting to be 11 (step S _73), no ignition of the first cylinder emit an ignition command signal from the output port P3 (step S _74), the process proceeds to the following steps: step S _29. If, when it has become a PC = 00 without becoming PC value is 11 to return to the determination start routine Thereby step S ₇₅ (step S _36). If the stage count value is not 1 in step S ₇₁ , it is further determined whether or not the stage count value is 2 (step S ₇₆ ), the PC
A value is taken in (step _S77 ), and it is determined whether this PC value is a value corresponding to the stage count value (S = 2), that is, 10 (step _S78 ). Here, the process proceeds to step S ₂₉ following step if PC = 10, returns to PC = 10 unless the starting subroutine (step S _36).

If the stage count value S is not 2 in step S ₇₆ , it is further judged whether or not the count value S is 3 (step S ₇₉ ). If S = 3, the PC value is determined. uptake (step S _80), the PC value forms a judgment as to whether or not the value i.e. 01 corresponding to the stage count value (S = 3) (step S _81). Where PC = 01
If no ignition of the second cylinder emit an ignition command signal from the output port P4 (step S _82), the process proceeds to step S ₂₉ following step. Back to PC = 01 unless the start subroutine at step S ₈₁ (step S _36).

In this way, the engine rotation state can be efficiently determined by determining whether the engine rotation state is normal only when the engine rotation speed is lower than the idle rotation speed, that is, when the engine rotation speed is not stable. it can. Further, when an abnormality is detected, the routine returns to the starting sub-routine without performing ignition, so that it is possible to prevent rotation abnormality such as reverse rotation due to erroneous ignition, and to quickly detect the rotation reference position, which is preferable.

In addition, in the above-described embodiment, the magnetic protrusion is formed on the rotating body 10.
Although four 12 are provided and one rotation of the rotating body 10 is composed of 7 stages, as shown in FIG. 11, six magnetic protrusions 12 are provided on the rotating body 10 to make one rotation of the rotating body 10 11 times. If the stage is used, it is possible to obtain more detailed rotation angle information.

In addition, in this embodiment, the pickup 13 facing the magnetic protrusion is used.
Although the position of the rotator is detected by a and 13b, the rotator 10 may be configured by a disk that blocks light according to the rotation and a photosensor that detects the light. However, in this case, the signal obtained by the photosensor must have such a time width that the signal input can be taken in again during execution of the interrupt subroutine executed by the computer upon the signal input.

EFFECTS OF THE INVENTION As described above, in the engine rotation state determination method according to the present invention, at least two detection portions are provided at a predetermined angular interval in the rotation direction of the rotating body, and the detection target is provided at the predetermined interval. At least two detection elements that generate a predetermined level of output each time the section passes the vicinity are provided near the rotation locus of the detected section, and the stage count value is the unit number each time the output of at least one of the detection elements is generated. The rotating body is added or subtracted, and both output levels of the sensing element that should correspond to the current value of the stage count value are compared with the current output levels of both the sensing elements and their corresponding functions do not match. Since it is determined that the rotation state of is abnormal, it is possible to determine whether the rotation state of the rotating body including the rotation direction of the rotating body is normal or abnormal.

[Brief description of drawings]

FIG. 1 is a diagram showing an ignition device of a two-cycle engine to which the present invention is applied, FIGS. 2A and 2B are waveform diagrams of the output signal of the pickup and the input signal of the input port shown in FIG. 1, and FIG. From Fig. 10 to Fig. 10, start subroutine, main routine, INT1, INT2 interrupt subroutine, stage count subroutine, INT1, INT2, which are executed by the control circuit, respectively.
FIG. 11 is a flowchart showing the interrupt subroutine, the start subroutine, the PC standby subroutine, the INT1 and INT2 interrupt subroutines, and FIG. 11 is a view showing the rotating body and the pickup of an embodiment different from that of FIG. Description of main part symbols 10 …… Rotating body 12 …… Magnetic protrusion 13 …… Pickup 16 …… Control circuit

Claims (3)

[Claims] 1. At least two detected parts provided at a predetermined angular interval in the rotation direction of a rotating body that responds to the rotation of an engine, and at least one detected part at an angular interval equal to the predetermined angular interval. The rotation at the time of starting the engine is performed by using a detection pulse generating means that is arranged in the vicinity of the rotation locus and that includes at least two detection elements that generate an output that exceeds a predetermined level each time the detected portion passes through the vicinity. A method for determining a rotation state of a body, wherein when the output level of the sensing element exceeds and falls below the predetermined level, the output values (P ₁ , P ₂ ) of the sensing element are set to "1" and "0", respectively. ", And the values are sequentially stored in the buffer memory and the output value (P ₁ , P ₂ ) of the sensing element is (0, 0).
It is detected that the value has become a value other than
_After the first stroke (S ₃ , S ₄ , S ₅ ) stored in _b ) and the output value (P ₁ , P ₂ ) of the sensing element (0, 0), the next value (1, 1 ) Is determined based on the stored value in the buffer memory, it is determined that the output values (P ₁ , P ₂ ) of the sensing element stored in the first memory are values other than the predetermined value. If you, the second step of determining that the rotation abnormality (S ₆ ~S _18), rotation state determination method for an engine, characterized in that it consists of. 2. In the second step, after the output value of the sensing element has passed the value of (0,0), the next value of the output value (P ₁ , P ₂ ) is (1,1) and ( If it is determined that a value of 0,0) than, that which takes in the after next value _{(S 6, S 7, S} 8, S 9, S 10), the output value (P _1, P ₂₎ (0,0) when it is determined that a value other than (S _15, S _16), in advance and stores the after next value in the second memory (S _17), the output value (P _1, P ₂₎ after next value to update the storage contents of said first memory the contents when it becomes a value (S ₁₆₎ of said second memory (0,0) of said output values (P _1, P ₂₎ is ( 1, 1) judgment process (S ₈ ~
Rotation state determination method of claims any preceding claim for an engine, which comprises a step of returning to S ₁₀₎ (S _18). 3. At least two detected parts provided at a predetermined angular interval in the rotation direction of a rotating body that responds to the rotation of an engine, and at least one detected part at an angular interval equal to the predetermined angular interval. The rotation state of the rotating body is discriminated by using a detection pulse generating means which is arranged in the vicinity of the rotation locus and which includes at least two detection elements which generate an output exceeding a predetermined level each time the detected portion passes through the vicinity. A step of adding or subtracting a unit number of stage count values each time the output level of at least one of the sensing elements reaches the predetermined level (S ₂₁ , S
₂₉ , S ₃₁ ) and the current value of the stage count value and the current output levels of both of the sensing elements are compared, and it is determined that the rotating state of the rotating body is abnormal based on the corresponding relationship. 2 steps (S ₂₅ , S ₂₆ , S _{33 to} S ₃₉ , S _{41 to} S ₅₄ ), the second step includes the stage count value, and the output levels of both the detection elements are both at the predetermined level. When the count value (S = 7) for waiting for a state exceeding S is reached, the process of ignoring the output of one of the sensing elements (S
₂₉ , S ₃₀ ) is provided.