JPS62182463A - Reverse revolution preventing device for internal combustion engine - Google Patents

Abstract

PURPOSE:To immediately prevent the reverse revolution of an internal combustion engine by immediately judging the reverse revolution when the angular signal counted by an angular signal counting means deflects from a prescribed value during one cycle of the standard signal and driving a cutting means. CONSTITUTION:When an internal combustion engine is switched from normal revolution to reverse revolution, the angular signal supplied from an angular signal generating means which is counted by an angular signal counting means becomes larger or smaller than a prescribed value in one cycle of the standard signal supplied from a standard signal generating means, and when the counted value deflects from the prescribed value, a counted value judging means immediately judges the reverse revolution of the internal combustion engine. When the reverse revolution is judged, a cut means is driven to stop the revolution of the internal combustion engine. Further, the angular signal and the standard signal for detecting the reverse revolution are used for controlling the internal combustion engine, and the need of installing a position sensor is avoided. Thus, the reverse revolution can be immediately prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reverse rotation prevention device for an internal combustion engine that detects reverse rotation of an internal combustion engine and immediately stops its rotation.

[Conventional technology]

Conventionally, this type of engine has a position signal generating means generate two position signals shifted by a predetermined angle in synchronization with the rotation of the internal combustion engine, and each position generated by the position signal generating means during forward rotation and reverse rotation. It has been proposed to detect reversal by utilizing the fact that the signal generation phases are opposite, and to cut off the ignition of the internal combustion engine (for example, Japanese Patent Laid-Open No. 13764/1983).

[Problem that the invention seeks to solve]

However, with the conventional system described above, reversal can only be determined when the internal combustion engine changes from normal rotation to reverse rotation and the generation phases of the two position signals become opposite to those during normal rotation, so it is not possible to switch from normal rotation to reverse rotation. There is a problem in that there is a time delay in determining whether a reversal occurs when the reversal occurs, and the reversal continues for a certain period of time.

Another problem is that a separate position sensor is required to detect reversal.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to be able to quickly determine whether the internal combustion engine is reversing, to immediately prevent reversal, and to eliminate the need for a new position sensor for preventing reversal.

[Means for solving problems]

Therefore, as shown in FIG. 1, the present invention includes a reference signal generating means that generates a reference signal at a reference position in synchronization with the rotation of the internal combustion engine, and a angle signal generating means for generating a plurality of angle signals;
an engine electronic control means that receives the angle signal and the reference signal and electronically controls at least one of the ignition timing and the fuel injection amount of the internal combustion engine; An angle signal counting means for counting angle signals, and determining whether or not a count value corresponding to the generation cycle of the reference signal in the angle signal counting means is a predetermined value, and if it is not a predetermined value, the internal combustion engine is in reverse rotation. A reversing device for an internal combustion engine, comprising: a count value determining means for determining that the internal combustion engine is reversing; and a cutting means for cutting at least one of ignition of the internal combustion engine and fuel when the count value determining means determines that the internal combustion engine is reversing. A prevention device is provided.

[Effect]

As a result, when the internal combustion engine switches from normal rotation to reverse rotation, the number of angle signals counted by the angle signal counting means during one cycle of the reference signal becomes less than or greater than the predetermined value, and in this way, the counted value becomes the predetermined value. When the internal combustion engine is no longer rotated, the count value determining means immediately determines that the internal combustion engine has rotated in reverse, and the cutting means is driven to stop the rotation of the internal combustion engine. Further, since the angle signal and reference signal input for detecting reverse rotation are originally used for controlling the internal combustion engine, there is no need to provide a separate position sensor.

〔Example〕

The present invention will be described below with reference to embodiments shown in the drawings.

FIG. 2 is a block diagram showing the overall configuration of one embodiment of the device of the present invention, and will be explained using a two-stroke, two-cylinder system as an example. 1
is a reference signal signal rotor, which has two teeth made of magnetic material on its outer periphery, and is attached to the crankshaft so that it rotates once per revolution of the crankshaft of the internal combustion engine. Reference numeral 2 denotes a reference signal pick-up coil disposed at a position facing the teeth of the reference signal signal rotor 1, and one output end of the coil is connected to the engine control unit (hereinafter referred to as EC) as the reference signal G.
(referred to as U) 11, and the other end is connected to ground 9. This reference signal G is the crank angle of lOo before top dead center (BTDC) of the first and second cylinders of the internal combustion engine (
CA). Reference numeral 6 denotes a signal rotor for angle signals, which has 24 teeth made of magnetic material at equal intervals on its outer periphery, and is attached to the crankshaft so that it rotates once per crankshaft rotation. Reference numeral 7 denotes an angle signal pickup coil disposed at a position facing each tooth of the angle signal signal rotor 6, and one output end of the coil is used as an angle signal Ne.
It is manually powered by CUII, and the other end is connected to earth 9. This angle signal Ne is designed to be output every 15° CA of the crankshaft. Reference numeral 10 designates other sensor signals, which are input to the ECU II together with the reference signal G and the angle signal Ne. Based on this information, a microcomputer (not shown) built in the ECU II calculates the optimum ignition timing and fuel injection amount. , the igniter 12 and the injector 13 are respectively driven by these calculation outputs.

FIGS. 3 and 4 show the reference signal G, the angle signal Ne, and the output states of the Ne counter when the internal combustion engine rotates in the normal direction and when the internal combustion engine rotates in the reverse direction.

During normal rotation of the internal combustion engine, 12 angle signals N are generated during one period of the reference signal G, as shown in FIGS. 3(a) and (b).
If e exists and the Ne counter is reset (cleared) with the next angle signal Ne after the reference signal G is generated, the count value of the Ne counter immediately before being reset will always be 11 as shown in Figure 3 (C). .

However, immediately after the rotation of the internal combustion engine switches from normal rotation to reverse rotation, as shown in FIGS. 4(a) and (b), the last reference signal G during normal rotation and the first reference signal G during reverse rotation are different. There are fewer or more angle signals Ne than 12 between
At this time, the count value immediately before the Ne counter is reset becomes a value smaller or larger than the predetermined value 11, as shown in FIG. 4(C).

Therefore, it can be immediately determined whether the internal combustion engine is rotating in the normal direction or in the reverse direction based on the count value of the Ne counter.

5 to 7 show flowcharts for determining the difference in signal output states, detecting reverse rotation, and activating the reverse rotation prevention device. This will be explained below with reference to FIG.

FIG. 5 shows an initialization routine, in which it is determined in step 20 whether or not the starter has been turned on. When the starter is turned on, the process proceeds to step 21, sets the value of the Ne counter to 11, proceeds to step 22, clears the reverse rotation detection flag FR, proceeds to step 23, clears the G flag XG, and proceeds to step 30 in FIG.

FIG. 6 shows a reverse rotation determination routine, in which it is determined in step 30 whether or not a G signal is input. If the G signal is not input, the process proceeds to step 34, where it is determined whether the G flag is 1 or not. At this time, the G signal has not been input even once, so XG is O, so return (wait for manual input of the G signal)
. If the G signal is inputted again in step 30, the process advances to step 31, sets 1 to the G flag XG, and steps 32
Proceed to. In step 32, it is determined whether the value of the Ne counter is 11 or not. At this time, since 11 has been entered in the Ne counter at step 21 in FIG. 5, the process moves to step 33. In step 33, the Ne signal input immediately after the G signal causes Ne
The value of the counter is cleared (reset), and the process proceeds to step 34, where it is determined whether the G flag XG is 1 or not. At this time, since the G flag XG is negative, the process moves to step 35, increments the Ne counter every time the Ne signal is input, and returns.

The process returns to step 30 and it is determined whether the next G signal has been input. If no input has been made yet, the process passes through step 34 and proceeds to step 35, where the Ne counter is counted up for each Ne signal. When the next G signal is input in step 30, the process passes through step 31 and proceeds to step 32. In step 32, it is determined whether the value of the Ne counter is 11 or not, and if it is 11, the process proceeds to steps 33, 34, and 35. If it is not 11, the process proceeds to step 36, sets the reverse rotation detection flag FR to 1, and returns.

FIG. 7 shows a reverse rotation prevention processing routine, and in step 40, the reverse rotation detection flag FR is set to 1 in step 36 of FIG.
It is determined whether or not. If it is 1, the process proceeds to step 41, where the fuel is cut by stopping the operation of the injector 13, and then the process proceeds to step 42, where the ignition is cut by stopping the operation of the igniter 12, thereby stopping the engine. .

As described above, this embodiment has a reference signal and an angle signal, and counts the angle signals to determine whether or not the count value of the angle signal when the reference signal is generated is a predetermined value. This system is characterized by determining that a reversal has occurred and cutting off either or both of the ignition and fuel so that the reversal does not continue.

In the above-mentioned embodiment, the present invention was applied to a two-stroke, two-cylinder internal combustion engine, but the present invention can be applied to an internal combustion engine with any number of cylinders. Since the present invention can be applied to a four-stroke internal combustion engine, it is also possible to prevent backfire, etc., which occurs during temporary reverse ignition of a four-stroke internal combustion engine.

Furthermore, in the above embodiment, it is determined whether the count value of the Ne counter is equal to the predetermined value α0 after the reference signal 4 is generated until the next angle signal Ne is generated. If the No counter is cleared when n (where n is an integer greater than or equal to 2) angle signals Ne are generated after the signal G is generated, the Ne counter is cleared after the reference signal G is generated. 1~n~1 until
Ne when a specific number of angle signals are generated among the
It may be determined whether the count value of the counter is a predetermined value. In this case, it is necessary to reduce the predetermined value by the number of angle signals Ne to be counted before the Ne counter is cleared.

〔Effect of the invention〕

As described above, in the present invention, when the angle signal counted by the angle signal counting means loses a predetermined value during one period of the reference signal, the counted value determining means immediately determines that the internal combustion engine has reversed. Since the rotation of the internal combustion engine is stopped by driving the cutting means, it is possible to quickly determine whether the internal combustion engine is reversing, and this has the excellent effect of being able to immediately prevent reversal. Furthermore, since the angle signal and reference signal input for detecting reverse rotation are originally used for controlling the internal combustion engine, there is no need to provide a separate position sensor.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to the claims of the present invention, FIG. 2 is a block diagram showing an embodiment of the device of the present invention, and FIGS. 3 and 4 show various parts of the above embodiment during normal rotation and when reverse rotation occurs. The waveform diagrams and FIGS. 5 to 7 are flowcharts showing the initial XI conversion routine, reversal determination routine, and reversal prevention processing routine of the microcomputer in the above embodiment. DESCRIPTION OF SYMBOLS 1... Signal rotor for reference signals, 2... Pick amplifier coil for reference signals, 6... Signal rotor for angle signals, 7... Pick-up coil for angle signals, engineering l.
...ECU, 12...igniter, 13...injector.

Claims (1)

[Scope of Claims] 1. Reference signal generating means for generating a reference signal at a reference position in synchronization with the rotation of the internal combustion engine; angle signal generation means for generating a signal; engine electronic control means for receiving the angle signal and reference signal to electronically control at least one of ignition timing and fuel injection amount of the internal combustion engine; and generation of the reference signal. An angle signal counting means that is repeatedly reset in synchronization with a cycle to count the angle signal, and determining whether a count value corresponding to the generation cycle of the reference signal in this angle signal counting means is a predetermined value, a count value determining means for determining that the internal combustion engine is running in reverse if the count value determining means determines that the internal combustion engine is running in reverse; and a cut that cuts at least one of the ignition and fuel of the internal combustion engine when the count value determining means determines that the internal combustion engine is running in reverse. A reverse rotation prevention device for an internal combustion engine, comprising means. 2. The reverse rotation prevention device for an internal combustion engine according to claim 1, wherein the predetermined value of the count value determining means is an odd number. 3. The count value of the angle signal counting means is reset by an angle signal generated immediately after the reference signal is generated, and the count value determining means generates the next angle signal after the reference signal is generated. A reverse rotation prevention device for an internal combustion engine according to claim 1 or 2, which determines whether or not a predetermined value is reached.