JPS60104770A - Electronic ignition timing controller for engine - Google Patents

Abstract

PURPOSE:To prevent an incomplete ignition or a misfire from occurring with certainty, by installing an energizing start timing compensation device which receives the output of an acceleration detecting device and quickens the energizing start timing for an ignition device, while quickening the energizing start timing in time of acceleration. CONSTITUTION:In time of engine operation, a reference signal is generated by a reference signal generating device 6 which generates signals at every specified crank angle, and on the basis of this reference signal, ignition timing resting on an engine operating state, that is, energizing end timing to an ignition device 41 is calculated by an ingition timing calculation device 38. Moreover, on the basis of the said reference signal, energizing start timing to the ignition device 41 is calculated by another energizing start timing calculation device 39. And in conformity with the energizing start timing and its end timing, the ignition device 41 is driven. At this juncture, when engine acceleration is detected by an acceleration detecting device 4, it is compensated so as to quicken the energizing start timing by an energizing start timing compensation device 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an electronic ignition control device for an engine.

[Prior art]

For example, in an electronic ignition timing control system for an engine that does not require a pulse generated every time the crankshaft rotates or a required angle pulse (hereinafter referred to as a synchronous calculation method), the ignition timing is determined by the top dead center signal, etc. A current is passed through the ignition coil based on the reference signal (hereinafter referred to as reference signal) K.
, R is disconnected, and the ignition timing is controlled.

FIG. 1 is a diagram for explaining the outline of control of an electronic ignition timing control device (hereinafter simply referred to as a control device) for an engine using a synchronous calculation method. In this figure, the % horizontal axis is the time axis t, the rising edge of the figure showing the reference signal indicates top dead center (hereinafter referred to as TDC), and the falling edge indicates a point advanced by a predetermined crank angle β from TDC (hereinafter referred to as BTI). ) C) 1- Show.

At the reference signal and the ignition coil charging current shown by the solid line in FIG.

At time 0, the time from the next ignition timing fBo is calculated as +118 from the ignition advance angle a and the time interval of the reference signal obtained so far, and at the same time, the necessary ignition energy is obtained in preparation for the next ignition. To charge the ignition coil [
From the required time rllc and the time interval of the reference signal obtained so far, calculate Tl as time 1'b from the next energization start time BO, and cut off the current to the ignition coil at time Ta from 800, respectively. The ignition timing is controlled by starting energization to the ignition coil after a time Tb. If the engine is in a steady state, the next BTI)C of Bo will arrive after the time expected at BoO, and at this point B1 as well, the `tL flow to the ignition coil will be cut off after `1゛a time. Therefore, the time during which the ignition coil is energized becomes the originally expected time TC, and a royal ignition is performed.

However, if acceleration occurs after the time of BO and the engine speed increases, the next B'l'lJC after BO will be longer than the time assumed at the time of Bo, as shown by the broken line in Figure 1. B
At point 11, ignition will take place after 'l'a' (Ta) time, so the time it takes to pass through the ignition coil is 1'C'.
As a result, the necessary ignition energy could not be obtained for a shorter period of time than the initially expected time TC, leading to problems such as not only not being able to produce a good amount of sake, but also misfires occurring in some cases.

In the above explanation, B'l is used as the reference signal for ignition timing.
'DC was used, but if TDC was used or TDC and B
It is clear that the above problem occurs even when both T1) and C are used.

[Purpose of the invention]

In view of these conventional problems, it is an object of the present invention to provide an electronic ignition timing control device for an engine that can always perform good ignition without misfire even when the engine speed rapidly increases due to acceleration. It is.

[Structure of the invention]

Accordingly, the present invention provides an electronic ignition timing control system for an engine in which a reference signal is generated by a reference signal generating means 61C that generates a signal every two predetermined engine angles, as shown in the functional block diagram of FIG. The ignition timing n addition means 38 calculates the ignition timing "that is, the end time of energization to the ignition means 41" determined by the operating state of the engine as a step from the reference signal, and the 1 energization start timing calculation means 39 calculates the ignition timing determined by the operating state of the engine. Based on the reference signal, the start timing of the energization to the ignition means 41 is calculated, and the ignition means 41 is controlled by μmυ according to the energization start time and the end time of the ignition means 41, but when the engine accelerates, In response to the output of the acceleration detection means 4, the energization start time correcting means 40 advances the energization start time.

〔Example〕

An actual #fli example of the present invention will be described below.

FIG. 3 shows an electronic ignition timing control system for an engine according to an embodiment of the present invention. In the figure, l is an engine, an intake passage 2 of the engine l is provided with a throttle valve 3, and 4 is a A throttle opening center ``-'' detects the opening degree of the throttle valve, and 5 is a negative pressure center ``-''.

In addition, in the figure, 6 is a crank angle sensor that detects the rotation angle of the crankshaft, 7 is a sensor length for detecting the entire battery voltage, 18 is an ignition coil, 9 is a tinutributor, lo is an ignition flag%, and 11 is a This is a signal that becomes U-pi when the starter switch is turned on.

12 is an input/output interface 13, a CPU 14
．． The control unit is composed of a memory 15. In addition to the program, the memory 15 also contains a map of the ignition advance angle determined by the operating state of the engine, and the energization time to the ignition coil (hereinafter referred to as "battery voltage") as a parameter.
Data table for basic energization time) and time for advancing the start time (hereinafter referred to as
Data such as data corresponding to acceleration correction time) is stored. Further, the CPU 14 determines whether or not the engine is in the starting mode depending on the operating state of the engine, and if the engine is in the starting mode, ignition is performed at Tl)C and energization is started at BTDe, but if the engine is not in the starting mode, the ignition progresses. Memory corner 1
5, calculate the next ignition time from the time interval of BTl)C as the time from BTI)C (hereinafter referred to as ignition time), and further perform acceleration judgment, and if it is not in an acceleration state, from memo IJ l 5. The basic energization time is simply read, but in the case of an acceleration state, the acceleration correction time l1JJ'f is read from the memory 15.

The time to start the next energization is calculated as the time from BTI)e (hereinafter referred to as the energization start time) from the thus calculated energization time to the ignition coil and the time interval of BTDC. BTIJC
After one ignition time has elapsed after detecting the current, ignition is performed by cutting off the current in the ignition coil, and at the same time, the current is turned on to the ignition coil after the energization start time has elapsed.
iI], the ignition coil is charged and the ignition timing is controlled.

Note that in the above configuration, the CPU 14 is
Ignition timing 2'l determining means 38, through 711. It realizes the functions of the start timing calculation means 39 and the "Ij + electric start time" correction means 40, and the above-mentioned two ink angle sensors 6 serve as the reference signal generation means 6 in FIG. The opening degree C/Z-4 is the acceleration detection means 4 in FIG. 2, and j! ! The ignition coil 8, the ignition repeater 9 and the ignition book 10 constitute the ignition means 41 shown in FIG. In this embodiment, the reference signal generating means 6 is configured to be able to generate TDC and BTDC.

Next, the operation will be explained in detail with reference to FIG. Here the fourth
The figure shows a flowchart of ignition timing control by the CPU 14.

The CPU 14 initializes the registers and the like in the CPU 14 (step 16), then reads the input information of the outputs of the sensors 4 to 7 and the starter switch signal 11 (step 17), and performs the following based on the read input information. A determination is made as to whether or not the mode is the starting mode (step 18). If the mode is the starting mode, the process proceeds to step 34; otherwise, the process proceeds to step 19.

In start mode, check TDC interrupt step 34
), if it is a TDC interrupt, turn off the ignition coil current.
1' DC ignition is performed (step 35).

If it is not a TDC interrupt, check the BTDC interrupt (Step 36), if it is not a BTDC interrupt, do nothing but BT
If it is a DC interruption, the ignition coil is started to be energized (Step 37), and in either case, the process returns to Step 17Vc. As described above, in the starting mode, ignition is performed at TDC, then the current to the ignition coil is cut off until BTDC, and B T
Power is started at DC and the ignition coil is charged until the next TDC.

If it is not the start mode, read the ignition advance angle α corresponding to the operating state of the engine from the memory 15 and calculate the ignition time Ta'z from the time interval of BTLIC (step 19).
Basic energization time 1'ci memory 15 according to fluctuation voltage
(step 20), then determine whether or not acceleration is occurring based on the change in the output of the throttle opening sensor 4 (step 21). If the acceleration is not in progress, the correction time 'l'diQ is set (step 23). State Loreha Memo IJ l
Read the acceleration correction time d from step 5 and set it as the correction time 1゛d, Step 22), and set the above basic energization time IllC.
Add the above correction time Td to find the energization time to the ignition coil (=Tc+Td), and calculate the energization start time Tb corresponding to the energization time by q from the BTIJC time interval Ill x. Step 24) move on. Step 2
5 checks the BTDC interrupt, IJ 'l' I)
If it is not a C interrupt, proceed to step 28, but if it is a BTDC interrupt, set the ignition time Ta to the color/return TA (step 26), further set the energization start time Tb to the counter TB (step 27), Return to step 17.

BTI) If it is not a C interrupt, count down the counter TA (step 28) and determine whether the counter value is 0 or not (step 29). If the counter value is 0, do nothing and go to step 31. However, if the counter value is 0, it means that it is time to ignite, so completely cut off the power to the ignition coil and ignite it (
step 30), then in step 31 the counter TB
(step 32), and if the counter value is not 0, do nothing and return to step 17, but if the counter value is O, start energizing. This means that the desired time has come, so start energizing the ignition coil.Step 33
)l, return to step 17.

If the engine is not in the starting mode as described above, as shown in Fig. 1, the engine is ignited during the ignition time Ta corresponding to the ignition advance angle α, and the energization time (=Tc+' rd) is the energization start time T
At step b, energization will start.

In the device of this embodiment as described above, the timing to start energizing the ignition coil is delayed when the engine accelerates, so even if the engine speed suddenly increases due to acceleration, the source of the ignition coil remains charged. Shortage situations can be avoided and good ignition can be guaranteed.

Incidentally, in the above embodiment, it is assumed that the acceleration correction time for advancing the energization start timing during acceleration is constant, but the acceleration correction time may be determined according to the degree of acceleration, or may be determined depending on the degree of acceleration. Of course, it may be determined according to the engine speed.

〔Effect of the invention〕

As described above, according to the present invention, in the engine's ignition timing control device, when the engine accelerates, the start timing is advanced in the path to the ignition coil, so that the engine speed increases due to acceleration. However, there is no incomplete ignition or misfire due to insufficient charging of the ignition coil, and since the energization start time is advanced only during acceleration, ignition timing can be controlled without damaging the ignition coil due to overheating. It's effective.

[Brief explanation of drawings]

Fig. 1 is a diagram for explaining the general control of a synchronous YTN: type electronic ignition control device, Fig. 2 is a functional block diagram showing the configuration of the present invention, and Fig. 3 is according to an embodiment of the present invention. FIG. 4 is a block diagram of an electronic ignition timing control device for an engine, and is a diagram showing a flowchart of arithmetic processing of the CPU 14 in the device. l...Engine, 3...Throttle valve, 4...Throttle once set/circle, 5...
...Negative pressure sensor, 6...Crank angle sensor, 7...Battery voltage sensor length -18...
・Ignition coil, 9...Tist distributor, 1
0.Old...Ignition plug 2, 12.Old...Control units), 14.River...CPU% 15..Group.Memory, 3
8...Ignition timing calculation means, 39...Turning start timing calculation means, 40...Electrification 1 temporary timing correction means, 41...Ignition means. Figure 1 7/II Btr Tt Bt'Bt Figure i

Claims (1)

[Claims] ignition means for igniting the engine; reference signal generation means for generating a signal at every predetermined crank angle of the engine; acceleration detection means for detecting the acceleration state of the engine; ignition timing calculation means for calculating the ignition timing as the position from 1 to 3; ignition start timing calculation means for calculating the energization start time to the ignition means based on the reference signal;