阅读说明：本技术 一种具有双触发线圈的高精度点火系统及方法 (High-precision ignition system with double trigger coils and method ) 是由 张斌 郑梅君 徐宝钧 胡银强 于 2019-09-11 设计创作，主要内容包括：本发明公开了一种具有双触发线圈的高精度点火系统及方法,包括：第一触发信号滤波处理模块,用于低速时为微控制单元提供计算控制,包括第一触发线圈,所述第一触发线圈的两端分别与所述微控制单元相连通；第二触发信号滤波处理模块,用于高速时为微控制单元提供计算控制；包括第二触发线圈,所述第二触发线圈的两端分别与所述微控制单元相连通。本发明采用了两个带计算输入的处理模块,分别用于发动机的低速和高速运行过程,MCU求得的点火延时值更加接近实际要求值,从而实现点火角度的高精度设计。(The invention discloses a high-precision ignition system with double trigger coils and a method, wherein the high-precision ignition system comprises the following steps: the first trigger signal filtering processing module is used for providing calculation control for the micro control unit at low speed and comprises a first trigger coil, and two ends of the first trigger coil are respectively communicated with the micro control unit; the second trigger signal filtering processing module is used for providing calculation control for the micro control unit at a high speed; the micro-control unit comprises a second trigger coil, and two ends of the second trigger coil are respectively communicated with the micro-control unit. The invention adopts two processing modules with calculation input, which are respectively used for the low-speed and high-speed running processes of the engine, and the ignition delay value obtained by the MCU is closer to the actual required value, thereby realizing the high-precision design of the ignition angle.)

1. A high precision ignition system with dual trigger coils, comprising:

the first trigger signal filtering processing module is used for providing calculation control for the micro control unit at a low speed, and comprises a first trigger coil, wherein two ends of the first trigger coil are respectively communicated with the micro control unit, and the first trigger coil is used for sequentially transmitting a first trigger signal A1, a second trigger signal B1 and a third trigger signal C1 to ports of the micro control unit GP1 and GP 2;

the second trigger signal filtering processing module is used for providing calculation control for the micro control unit at a high speed; the device comprises a second trigger coil, wherein two ends of the second trigger coil are respectively communicated with the micro control unit and are used for sequentially transmitting a first trigger signal A2, a second trigger signal B2 and a third trigger signal C2 to ports of GP3 and GP4 of the micro control unit;

the waveform interval time of the adjacent first trigger signal A1 is the time value T1 required by the flywheel to rotate 360 degrees;

the waveform interval time of the second trigger signal B1 and the third trigger signal C1 is a time value t1 required when the flywheel rotates by N degrees;

the waveform interval time of the adjacent first trigger signal A2 is the time value T2 required by the flywheel to rotate 360 degrees;

the waveform interval time of the second trigger signal B2 and the third trigger signal C2 is the time value t2 required when the flywheel rotates by N degrees.

2. The ignition system of claim 1, wherein the micro control unit comprises,

the monitoring module is used for monitoring the state of each module;

the signal acquisition module is used for acquiring a trigger signal;

and the calculation module is used for calculating the current engine rotating speed value, the ignition angle required value and the ignition time delay.

3. The ignition system of claim 1, further comprising,

and the power supply module is used for sampling and storing energy through the voltage waveform induced by the charging coil and providing power voltage for the micro control unit.

4. The ignition system of claim 1, further comprising,

the ignition energy storage module charges the charging capacitor C11;

the ignition control module is used for controlling the charging capacitor C13 to charge and discharge;

and the flameout detection module is used for detecting the state of the flameout switch of the engine.

5. The ignition system of claim 1, wherein the first trigger signal filtering processing module comprises:

the first resistor, the first capacitor and the first voltage stabilizing diode are connected in parallel to form a first branch circuit, and the second resistor is connected in series with the first diode and then connected in parallel with the first branch circuit to form a second branch circuit;

the third resistor, the second capacitor and the second voltage stabilizing diode are connected in parallel to form a third branch circuit, and the fourth resistor is connected in series with the first variable capacitance diode and then connected in parallel with the third branch circuit to form a fourth branch circuit;

the second branch circuit and the fourth branch circuit are grounded in series, and the first trigger coil is connected with a first diode and a first variable capacitance diode;

the second branch and the fourth branch are respectively connected with ports of micro control units GP1 and GP 2.

6. The ignition system of claim 1, wherein the second trigger signal filtering processing module comprises:

a fifth resistor, a third capacitor and a third voltage stabilizing diode are connected in parallel to form a fifth branch circuit, and a sixth resistor is connected in series with a second diode and then connected in parallel with the fifth branch circuit to form a sixth branch circuit;

the seventh resistor, the fourth capacitor and the fourth voltage stabilizing diode are connected in parallel to form a seventh branch circuit, and the eighth resistor and the third diode are connected in series and then connected in parallel with the seventh branch circuit to form an eighth branch circuit;

the sixth branch and the eighth branch are grounded in series, and the second trigger coil is connected with a second diode and a third diode;

the sixth branch and the eighth branch are respectively connected with ports of micro control units GP3 and GP 4.

7. The ignition system of claim 1, wherein the first trigger signal filtering processing module comprises:

a collector and an emitter of the first triode are connected in parallel with the fifth capacitor, a base and the emitter are connected in parallel with the ninth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP1 through a tenth resistor and a power supply voltage, and the base is connected with the eleventh resistor and the first trigger coil in series;

and a collector and an emitter of the second triode are connected in parallel with the sixth capacitor, a base and the emitter are connected in parallel with the twelfth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP2 through a thirteenth resistor and a power supply voltage, and the base is connected in series with the fourteenth resistor and the first trigger coil.

8. The ignition system of claim 1, wherein the second trigger signal filtering processing module comprises:

a collector and an emitter of the third triode are connected in parallel with the seventh capacitor, a base and the emitter are connected in parallel with the fifteenth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP3 through a sixteenth resistor and a power supply voltage, and the base is connected in series with the seventeenth resistor and the second trigger coil;

and a collector and an emitter of the fourth triode are connected in parallel with the eighth capacitor, a base and the emitter are connected in parallel with the eighteenth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP4 through a nineteenth resistor and a power supply voltage, and the base is connected in series with the twentieth resistor and the second trigger coil.

9. A high precision ignition method with double trigger coils for an ignition system according to any one of claims 1 to 8,

s1 and GP1 sample and input the first trigger signal A1, obtain T1, and calculate the current rotating speed value and ignition angle required value of the engine;

s2, judging whether the current rotating speed value of the engine is at a high speed value, if so, executing a step S3, and if not, executing a step S5;

s3 and GP3 sample and input the first trigger signal A2, obtain T2, and calculate the current rotating speed value and ignition angle required value of the engine;

s4, GP3 samples and inputs the second trigger signal B2, GP4 samples and inputs the third trigger signal C2, and therefore t2 is obtained; calculating ignition time delay through t 2; step S6 is executed;

s5, GP2 samples and inputs the second trigger signal B1, GP1 samples and inputs the third trigger signal C1, and therefore t1 is obtained; judging that the ratio of T1 to T1 meets the condition that the normal phase value & T1 is smaller than the maximum set value, if the ignition time delay is calculated through T1, executing step S6; if not, go to step S7;

s6, waiting for the ignition delay time to arrive, and outputting an ignition signal by the micro control unit;

and S7, the engine is in a recoil state and does not output an ignition signal.

10. The ignition method according to claim 9, further comprising, before step S1, inducing a voltage through a charging coil for powering up the micro control unit.

Technical Field

The invention relates to the field of small gasoline engines, in particular to a high-precision ignition system with double trigger coils and a method thereof, which are applied to small internal combustion gasoline engines, such as lawn mowers, brush cutters, hedge trimmers, chain saws and the like in the field of garden tools.

Background

The digital igniter for the traditional small gasoline engine adopts a Microcontroller Unit (MCU) as a core control Unit, provides a proper ignition signal for the normal work of the gasoline engine, and obtains the output moment of the ignition signal by recalculating the periodic value of one circle of rotation of a magnetic flywheel. The speed difference of different positions in the cycle process of one rotation of the magnetic flywheel is large, because the gasoline engine comprises compression of mixed gas in a cylinder in the working process, the rotating speed of the magnetic flywheel is sharply reduced in the compression process, the ignition moment calculated after one rotation of the magnetic flywheel cannot meet the optimal ignition moment required by the engine, the ignition moment output by the ignition device has relatively large deviation, and the problems of stability of idling of the engine, acceleration and deceleration performance and jitter of the whole engine during high-speed running are easily influenced.

The optimal ignition advance angle at low speed and high speed of the engine is different with the rotation speed, and generally the ignition angle at low speed is required to be about 10 degrees before the top dead center, and the ignition angle at high speed is required to be about 30 degrees before the top dead center. Different ignition position requirements cannot meet the requirements of low-speed and high-speed high ignition precision of the engine when a single trigger coil is adopted for sampling and calculating.

Therefore, aiming at the defects of the prior art, how to satisfy the requirements of low speed and high speed of the engine on high ignition precision is a problem to be solved urgently in the field.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a high-precision ignition system with double trigger coils and a method. Two processing modules with calculation input are adopted and are respectively used for the low-speed running process and the high-speed running process of the engine, and the ignition delay value obtained by the MCU is closer to the actual required value, so that the high-precision design of the ignition angle is realized.

In order to achieve the purpose, the invention adopts the following technical scheme:

a high precision ignition system with dual trigger coils comprising:

the first trigger signal filtering processing module is used for providing calculation control for the micro control unit at a low speed, and comprises a first trigger coil, wherein two ends of the first trigger coil are respectively communicated with the micro control unit, and the first trigger coil is used for sequentially transmitting a first trigger signal A1, a second trigger signal B1 and a third trigger signal C1 to ports of the micro control unit GP1 and GP 2;

the second trigger signal filtering processing module is used for providing calculation control for the micro control unit at a high speed; the device comprises a second trigger coil, wherein two ends of the second trigger coil are respectively communicated with the micro control unit and are used for sequentially transmitting a first trigger signal A2, a second trigger signal B2 and a third trigger signal C2 to ports of GP3 and GP4 of the micro control unit;

the waveform interval time of the adjacent first trigger signal A1 is the time value T1 required by the flywheel to rotate 360 degrees;

the waveform interval time of the second trigger signal B1 and the third trigger signal C1 is a time value t1 required when the flywheel rotates by N degrees;

the waveform interval time of the adjacent first trigger signal A2 is the time value T2 required by the flywheel to rotate 360 degrees;

the waveform interval time of the second trigger signal B2 and the third trigger signal C2 is the time value t2 required when the flywheel rotates by N degrees.

Further, the micro control unit comprises a microcontroller unit,

the monitoring module is used for monitoring the state of each module;

the signal acquisition module is used for acquiring a trigger signal;

and the calculation module is used for calculating the current engine rotating speed value, the ignition angle required value and the ignition time delay.

Further, the ignition system further comprises,

and the power supply module is used for sampling and storing energy through the voltage waveform induced by the charging coil and providing power voltage for the micro control unit.

Further, the ignition system further comprises,

the ignition energy storage module charges the charging capacitor C11;

the ignition control module is used for controlling the charging capacitor C13 to charge and discharge;

and the flameout detection module is used for detecting the state of the flameout switch of the engine.

Further, the first trigger signal filtering processing module includes:

the first resistor, the first capacitor and the first voltage stabilizing diode are connected in parallel to form a first branch circuit, and the second resistor is connected in series with the first diode and then connected in parallel with the first branch circuit to form a second branch circuit;

the third resistor, the second capacitor and the second voltage stabilizing diode are connected in parallel to form a third branch circuit, and the fourth resistor is connected in series with the first variable capacitance diode and then connected in parallel with the third branch circuit to form a fourth branch circuit;

the second branch circuit and the fourth branch circuit are grounded in series, and the first trigger coil is connected with a first diode and a first variable capacitance diode;

the second branch and the fourth branch are respectively connected with ports of micro control units GP1 and GP 2.

Further, the second trigger signal filtering processing module includes:

a fifth resistor, a third capacitor and a third voltage stabilizing diode are connected in parallel to form a fifth branch circuit, and a sixth resistor is connected in series with a second diode and then connected in parallel with the fifth branch circuit to form a sixth branch circuit;

the seventh resistor, the fourth capacitor and the fourth voltage stabilizing diode are connected in parallel to form a seventh branch circuit, and the eighth resistor and the third diode are connected in series and then connected in parallel with the seventh branch circuit to form an eighth branch circuit;

the sixth branch and the eighth branch are grounded in series, and the second trigger coil is connected with a second diode and a third diode;

the sixth branch and the eighth branch are respectively connected with ports of micro control units GP3 and GP 4.

Alternatively, the first trigger signal filtering processing module further includes:

a collector and an emitter of the first triode are connected in parallel with the fifth capacitor, a base and the emitter are connected in parallel with the ninth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP1 through a tenth resistor and a power supply voltage, and the base is connected with the eleventh resistor and the first trigger coil in series;

and a collector and an emitter of the second triode are connected in parallel with the sixth capacitor, a base and the emitter are connected in parallel with the twelfth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP2 through a thirteenth resistor and a power supply voltage, and the base is connected in series with the fourteenth resistor and the first trigger coil.

Alternatively, the second trigger signal filtering processing module further includes:

a collector and an emitter of the third triode are connected in parallel with the seventh capacitor, a base and the emitter are connected in parallel with the fifteenth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP3 through a sixteenth resistor and a power supply voltage, and the base is connected in series with the seventeenth resistor and the second trigger coil;

and a collector and an emitter of the fourth triode are connected in parallel with the eighth capacitor, a base and the emitter are connected in parallel with the eighteenth resistor, the emitter is grounded, the collector is connected with a port of the micro control unit GP4 through a nineteenth resistor and a power supply voltage, and the base is connected in series with the twentieth resistor and the second trigger coil.

The invention also provides a high-precision ignition method with double trigger coils, which is used for the ignition system of the invention and comprises the following steps of,

s1 and GP1 sample and input the first trigger signal A1, obtain T1, and calculate the current rotating speed value and ignition angle required value of the engine;

s2, judging whether the current rotating speed value of the engine is at a high speed value, if so, executing a step S3, and if not, executing a step S5;

s3 and GP3 sample and input the first trigger signal A2, obtain T2, and calculate the current rotating speed value and ignition angle required value of the engine;

s4, GP3 samples and inputs the second trigger signal B2, GP4 samples and inputs the third trigger signal C2, and therefore t2 is obtained; calculating ignition time delay through t 2; step S6 is executed;

s5, GP2 samples and inputs the second trigger signal B1, GP1 samples and inputs the third trigger signal C1, and therefore t1 is obtained; judging that the ratio of T1 to T1 meets the condition that the normal phase value & T1 is smaller than the maximum set value, if the ignition time delay is calculated through T1, executing step S6; if not, go to step S7;

s6, waiting for the ignition delay time to arrive, and outputting an ignition signal by the micro control unit;

and S7, the engine is in a recoil state and does not output an ignition signal.

Further, before step S1, the method further includes inducing a voltage through a charging coil for powering up the micro control unit.

Compared with the prior art, the invention adopts two trigger modules with calculation input, the instantaneous rotating speed of the flywheel before ignition is obtained through the calculation modes of t1 and t2 in the low-speed and high-speed running process of the engine, and the instantaneous speed is closer to the real rotating speed value before ignition work than the average speed of a whole circle at the moment, so that the ignition delay value obtained by the MCU through t1 and t2 is closer to the actual required value, thereby realizing the high-precision design of the ignition angle, controlling the precision of the actual ignition angle within +/-1 DEG on the engine, and enabling the engine to show better stability.

Drawings

FIG. 1 is a block diagram of a high precision ignition system with dual trigger coils according to one embodiment;

FIG. 2 is a circuit diagram of a first trigger signal filtering module and a second trigger signal filtering module;

FIG. 3 is a schematic voltage waveform diagram of a reference point corresponding to the circuit configuration of FIG. 2;

fig. 4 is another circuit configuration diagram of the first trigger signal filtering processing module and the second trigger signal filtering processing module;

FIG. 5 is a schematic voltage waveform diagram of a reference point corresponding to the circuit configuration of FIG. 4;

fig. 6 is a flowchart of a high-precision ignition method with dual trigger coils according to a second embodiment.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.

It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the components related to the present invention are only shown in the drawings rather than drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of the components in actual implementation may be changed freely, and the layout of the components may be more complicated.

The invention is further described with reference to the following drawings and specific examples, which are not intended to be limiting.