JPH01227869A - Ignition timing controller - Google Patents

Abstract

PURPOSE:To solve the problem of insufficiency of both electricity supply period and the secondary output voltage at the time of acceleration and prevent reduction in performance of an engine by compensatingly increasing the electricity supply period required for an ignition coil to generate the specified secondary output voltage according to the revolution cycle of an engine. CONSTITUTION:A plurality of means 4C and 4D generates the reference position signals at the different angular positions of a plurality of cranks. A means 6 counts the revolution cycle of an engine according to one of these reference position signals. A means 20 arithmetically operates the reference supply period for an ignition coil 42 and a means 23 compensates the reference supply period according to the revolution cycle of the engine. On the other hand a means 9 calculates the ignition timing, a means 21 calculates the supply starting timing and a means 22 generates a supply command. And responding to the supply command from a means 22, an ignition coil 42 is electrified and a means 40 controls the cut-off of the supply for the ignition coil 42 in response to the preceeding ignition command of the means 30 or 31.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ignition timing control device that electronically controls the ignition timing of an engine.

[Conventional technology]

Figures f45 to 7 show conventional ignition timing control devices. In the figure, (1) is the crankshaft of a 1-cycle 4-cylinder engine, (2) is a disk fixed to this crankshaft and rotating as the shaft rotates, and the disks are spaced at 180° intervals on the circumference of this disk. Magnetic material (3A) at the position (
3B) is fixedly attached. (4C) and (4D) are arranged close to the outer periphery of the disk (2) with a predetermined angle difference from each other, and the magnetic bodies (3A) or (3B)
When facing the reference position pulse P6. Electromagnetic pickup (4D) with xi pickup that emits Pd respectively.
is provided to detect the crank angle position corresponding to the latest ignition timing within the ignition timing control angle range of the engine, and the electromagnetic pickup (4C) is located in the direction of the outer circumference of the disc 2 from the position of the electromagnetic pickup (4D). The reference position pulses Pc and Pd are alternately sent out each time the crankshaft 1 rotates 90 degrees. (5) is the clock pulse C
(6) is a period measuring means for measuring the reference position pulse P60 time interval T6 based on the clock pulse CP of the oscillator (5); (9) is a period measuring means for measuring the time interval T6 of the reference position pulse P60 based on the clock pulse CP of the oscillator (5); Based on information S! Ignition timing calculation means calculates the ignition advance angle value θ based on the crank reference position to be detected by lE & pickup (4D). Required basic energization time T
The basic energization time calculation means for calculating l, 00 inputs the above-mentioned time interval Ta and point large advance angle, and calculates the reference position pulse P.
This is an ignition time calculation means that calculates and outputs the time T11 from when pulse a is sent until ignition in synchronization with the reference position pulse Pa using a method described later. From this time Ta and the basic energization time Tl of the ignition coil, the energization start time calculation means (2) calculates the time TofT from the generation of the reference position pulse Pa to the start of energization of the ignition coil (turn). ) inputs the clock pulse cp, the reference position pulse Pa, and the energization start time Toff, and outputs the energization command signal Pon to start energizing the point large coil (6) after the start time Ton has elapsed since the generation of the reference position pulse P6. Time Ts output from the ignition time calculation means α0, clock pulse CP
.

and the first ignition command output means (to) which inputs the reference position pulse Pa outputs an ignition command signal P spk which cuts off the current to the ignition coil when a time T8 has elapsed from the time when the reference position pulse PI+ was input. occurs.

- The ignition command output means (b) for blade 2 is the reference position pulse P
A second ignition command signal Pmd+ is generated in synchronization with the d input. The ignition control signal output means synchronizes with the energization command signal Pon, inverts the electrical state from the t''' level to the ``l (II level), and outputs the first ignition command signal Pmpk or the second ignition command signal Pmpk.
ignition control signal output means for transmitting an ignition control signal P3 that inverts the electrical state from the "H" level to the 'L' level in synchronization with whichever of the ignition command signals Psd is generated earlier in time; configured.

This ignition control signal Ps activates the ignition devices θ, drives the ignition coil 4, and ignites the engine.

Now, the reference position pulses Pa sent out from the electromagnetic pickup (4C) are sequentially set as P1, Po2, Pa3, .
In the case of Pa4 (Figure 6a) 1. The period measuring means (6) uses the reference position pulse Po2 based on the clock pulse CP of the reference oscillator (5) to output the reference position pulses Po2 and Pal during the manual operation.
The pulse period Te2 is time-measured.

When the reference position pulse Pe2 is sent n, the one ignition time calculating means 0Q calculates the time Ts2 (FIG. 2 0) from the time interval T6 and the ignition advance angle value θ to the next ignition time using the following equation.

As mentioned earlier, after the time Ts2 determined by this equation (1) has elapsed since the reference position and the generation of the pulse Pe2, the first ignition command output means generates the ignition command signal Pspk2, which is the timing for cutting off the current in the ignition coil ring. do.

Ignition coil (6) in the ignition cycle corresponding to this ignition
The start of energization is determined by the energization start time calculation means (2) based on the time Tof from the generation of the reference position pulse Po2 to the start of energization.
It is found as f. In other words, energization start time calculation means ■
Now, the energization start time ToH is calculated by subtracting the basic energization time Tl obtained by the basic energization time calculation means (7) from the time T3 from the reference position pulse P6 to ignition, which was previously obtained by the ignition time calculation means α0.

Torf=TS-Tl (2) 1 ignition control in which the energization command output means is activated at the time of generation of the reference position pulse Pa, and generates the energization command signal (Fig. 6a) after the lapse of the energization start time Toff. The signal output means is
When this energization command signal Pon is input, energization of the ignition coil is started, and the second ignition command signal Psd (Fig. 6e) is synchronized with the first ignition command signal Pspk or reference position pulse Pd (Fig. 6b). ), the ignition control signal Ps (fi6 Figure f
) occurs.

The ignition timing control device shown in FIG. 5 is configured in this way, and when the engine rotation is constant, the time interval T of the reference position pulse Pa is
Since C is constant and the first ignition command signal Papk is generated before the second ignition command signal Psd, ignition is performed by the first ignition command signal Ps pk. Furthermore, during acceleration as shown in Fig. 7, the engine rotation increases with each ignition, and the time interval T6 of the reference position pulse PC decreases with each ignition. The time interval between the actual reference position pulses pc is shorter than TC. Therefore, the ignition advance angle value θ is 0
, the second ignition command signal Psd (Fig. 7) is determined from the ignition command signal Pspk of j@1 (Fig. 7C).
.

is generated first, and the ignition control signal P is set so that the ignition is performed in synchronization with the ignition command Psd of ignition 2, that is, the reference position pulse Pd.
8 is composed. (Fig. 7f). This prevents ignition from being delayed from the reference position pulse Pd even in an accelerated state.

If there is no ignition caused by this second ignition command signal Psd, [
If ignition is performed using only the first ignition command signal Pspk, the first ignition command signal Pspk will occur at a time considerably later than the second reference position pulse Pd during acceleration, resulting in an abnormally delayed ignition. The engine is ignited at this position, causing problems such as low engine output.

As described above, in order to realize ignition control with good responsiveness even during acceleration in this type of ignition timing control device, ignition restriction using the second ignition command signal @Pad can be said to be an appropriate method.

[Problem to be solved by the invention] By the way, the ignition timing control device shown in FIG.
Although abnormal retardation is prevented by the ignition command signal Psd, the energization of the ignition coil is started before the basic energization time Tl from the first ignition command signal Pspk. (Fig. 7d) Therefore, after the start of energization by the energization command signal Pon, under the condition that ignition is performed not by the first ignition command signal Pspk but by the second ignition command signal Psd that occurs temporally earlier, the substantial The energization time is shorter than the basic energization time Tl. (f @ Pa2 in Fig. 7 f) For example, 1. Under normal driving conditions, the most rapid change in rotational speed occurs when racing from an idle condition.

Approximately 1100 rpm in one ignition cycle at around 1000 rpm
Increase the rotation speed by a certain amount. ! @ In the ignition timing control device shown in Figure 5, the shortage of energization time is most noticeable when the ignition advance angle value θ is 0, and in the racing condition described above, the shortage of energization time is most noticeable.
The ignition time Ta at 00 rpm (To=15ms) is (1
) is calculated as Ts=15 (ms). On the other hand, if the engine speed increases at a rate of 1100 rpm in one ignition cycle, the time Tod from the generation of the reference position pulse pc to the second ignition command signal Psd is approximately 14,3 (
ms), and a time difference of Tad-Tsl-IO, 7 (ms) occurs, resulting in a shortage of 0.7 (ms) in the energization time.

In particular, in engines with a high maximum rotation speed, such as recent DOHC engines, in order to ensure output voltage in the high rotation range, the primary current rises quickly so that the specified secondary output can be obtained in a short energization time. For example, in an ignition coil with a basic energization time Tl of 3 (ms), the secondary output voltage will drop by 25% even if the energization time is short by only 0.7 (m, ). Engine performance may deteriorate or engine misfire may cause suffocation.

No matter how accurately the basic energization time Tl required to obtain a predetermined secondary output is calculated by the basic energization time calculation means 4, the ignition coil energization time is inevitably short because it is reduced during acceleration.

This invention was made to solve the above-mentioned problems, and it prevents the occurrence of abnormal retardation of the ignition timing when the engine speed increases due to acceleration, and also prevents the ignition coil from being retarded due to insufficient energization time of the ignition coil. It is an object of the present invention to provide an ignition timing control device that also prevents insufficient output voltage.

[Means to solve the problem]

The ignition timing control means according to the present invention includes an energization time correction means for correcting the energization time of the ignition coil-secondary current according to the rotation period of the engine.

[Effect]

In this invention, since the ignition coil-secondary current conduction time is corrected in accordance with the rotation period of the engine, a sufficient secondary voltage can always be obtained.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. In FIG. 1, parts that are the same as those in FIG. 5 are given the same reference numerals.
The energization time correction means determines the energization time of the ignition coil by correcting the basic energization time Tl of the ignition coil calculated in accordance with the measurement period To of the period measurement means (6).

The energization time shortage ΔT calculated by the energization time correction means (to) is set so that the ignition coil's energization time responds without shortage to the acceleration of the rotation speed increase of 1100 rpm in one ignition cycle, and The amount of correction is calculated using the following equation (3) so as not to increase the amount of correction more than necessary and increase the consumption power of the ignition device and the heat generation of the ignition coil.

ΔT=-X(To)2... Equation (3) in (3) is when the engine speed determined from the period Ta at the time of time setting is No (rpm), the engine is 90 'When igniting after rotating, N e + 50
Assuming that the rotational speed increases by a considerable amount (rpm), the insufficient time Δt when there is no energization time correction is determined as follows, and the correction amount JT is set to compensate for this insufficient time.

No = □ 2XT.

If the energization time correction RAT is expressed as a ratio of time to one ignition period To, it will be as shown in FIG. 3. The rate of correction is small in the high rotation range, and conversely, the rate of correction is large in the low rotation range.

The basic energization time Tl is corrected by this correction amount ΔT, and the actual energization w1 time control value becomes Tl+ΔT.

Therefore, the energization start time that determines the energization start time of the ignition coil (6) is expressed by the following equation (42).

Toff=Ts-(TII+/lT) @ a
@ @ (4) Figure 2 shows the operation of this embodiment during acceleration. Since the energization start time is earlier by ΔT (FIG. 2C), the ignition control signal P8 can ensure a sufficient energization time even if ignition is performed at Psd. (Fig. 2 f) With this correction, considering the above-mentioned condition where the rotational speed increases by 1100 rpm in one ignition cycle at around 1000 rpm, (3)
From the formula, the overcurrent time correction amount T is 0.7 (ms), which can compensate for the 0.7 (ms) shortage of current application time.

As described above, according to the formula (3), it is possible to compensate for the lack of energization time throughout the entire engine rotation range, and prevent engine malfunctions due to insufficient secondary output voltage.

Now, although the above correction formula (3) is simple as a formula.

If this operation is attempted to be performed by a low-level microcomputer, processing time is required to execute the multiplication, which may lead to problems with the S/W configuration.

Therefore, equation (3) may be approximated by an equation that is easier to calculate.
For example, if the following formula (5) is used, the engine rotation speed is 50 Or
Insufficient energization time can be corrected for the above acceleration conditions in the range from pm to 220 rpm.

If the above-mentioned energization time correction fiAT is expressed as a ratio of time to one ignition period To, as in FIG.
It becomes a diagram.

In addition to these equations, other equations can be considered that correct the insufficient energization time for engine acceleration based on the engine rotation period. The degree of acceleration varies depending on the engine model, and even if an optimal energization time correction formula is provided for each engine, it will not affect the essence of the present invention. In addition, the engine rotation period used for this energization time correction is determined by measuring the period between different predetermined rotation angles of the engine,
The rotation period may be predicted by decreasing the rotation period.

Furthermore, in the above embodiment, magnetic pickups (4C) and (4D) are used to detect the crank reference angular position.
For example, two detectors were used at the reference position Pa.
2 using an angle detector that changes from a low level to a high level at the reference position Pd and from a high level to a low level at the reference position Pd.
Alternatively, one magnetic pickup may be used to detect both Pa and Pd reference positions in chronological order, and a separate detector may be used to determine Pc and Pd. You may.

〔Effect of the invention〕

As described above, according to the present invention, the energization time required for the ignition coil to generate a predetermined secondary output voltage, calculated in advance, is increased in accordance with the rotation period of the engine. Even when the cycle is shortened, there is no shortage of energization time, which has the effect of preventing engine performance deterioration and suffocating phenomena due to insufficient secondary output voltage of the ignition coil.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an ignition timing control device which is an embodiment of the present invention, Fig. #42 is a waveform diagram explaining the operation of Fig. 1,
Figure 3 and Figure 1'R4 are characteristic diagrams that explain the operation of Figure 1, Figure 5 is a block diagram of a conventional ignition timing control device, and Factor 6 and Figure 7 are Figure S. FIG. 2 is a waveform diagram illustrating the operation of FIG. l...Crankshaft, 2...Disc, 3A, 33...
magnetic material. 4C, 4D... Electromagnetic pickup, 5... Oscillator,
6... Period measuring means, 9... Ignition timing calculating means, 1
0... Ignition time calculation means, 20... Basic energization time calculation means. 21... Energization start time calculation means, 22 Energization command output means, 23... Energization time correction means, 30... Ignition command output means for ring 1, 31... Ignition command output means for f42, 40. ...Ignition control signal output means, 41...Ignition device, 42...Ignition coil

Claims (1)

[Claims] a first reference position detection means that generates a first reference position signal at a predetermined crank angle position of the engine; and a second reference position detection means that generates a second reference position signal at a predetermined crank angle position different from the crank angle. a reference position detection means, a rotation period measurement means for determining the rotation period of the engine from at least the first or second reference position signal, and a basic energization time for determining the basic energization time required for the primary current of the ignition coil to reach a predetermined value. energization time calculation means; energization time correction means that corrects the basic energization time according to the rotational cycle of the engine to determine the energization time of the ignition coil; and ignition timing calculation means that calculates the ignition timing according to the operating state of the engine. means for calculating the ignition time from the first reference position to the ignition timing from the rotation period and the ignition timing; energization start time calculating means for calculating the energization start time up to the energization start time of the ignition coil; and generating an energization command signal that starts energization of the ignition coil after the energization start time has elapsed from the time when the first reference position signal is generated. energization command output means; first ignition command output means for generating a first ignition command signal for cutting off the energization of the ignition coil after the ignition time has elapsed from the generation of the first reference position signal; A second part that cuts off the energization of the ignition coil when the reference position signal is generated.
a second ignition command output means for outputting an ignition command signal;
An ignition control signal that starts energizing the ignition coil in response to the energization command signal and cuts off energization to the ignition coil in response to the ignition command signal, whichever occurs earlier in time, such as the first ignition command signal or the second ignition command signal. An ignition timing control device comprising an ignition control signal output means for outputting an ignition control signal to an ignition device.