JPS58206878A - Reverse rotation preventing apparatus for internal-combustion engine - Google Patents

Abstract

PURPOSE:To prevent reverse rotation of an engine, by producing pulse signals the time ratio of which at the time of normal rotation of the engine is different from that at the time of reverse rotation of the engine, controlling charging and discharging of a capacitor, and detecting the voltage of said capacitor. CONSTITUTION:Since variation of the magnetic flux at the time when a rotor 19 of a ringer 1 is turned in normal direction is different from that when the rotor 19 is turned in reverse direction, a wave form having a different time ratio of a high level and a low level can be obtained. When the level of the shaped output is L, current is passed through a transistor A308, so that a capacitor 312 is charged. On the other hand, when the output of a wave-form shaping circuit 2 is inverted and its level becomes H, current is passed through a transistor 310, so that charge of the capacitor 312 is discharged. Thus, since the charging period of the capacitor 312 is longer than the discharging period at the time of reverse rotation, the charging voltage of the capacitor 312 is increased gradually. When the charging voltage is raised to a trigger level, an engine stopping means 5 is set into operation to prevent reverse rotation of the engine.

Description

[Detailed description of the invention] The present invention relates to (1) an internal combustion engine, particularly a two-stroke internal combustion engine; This invention relates to a reverse rotation prevention device.

The present invention provides a time ratio generating means that generates a high level and a low level dq according to the rotation of an internal combustion engine, and a time ratio of a quotient level and a low level when the engine rotates forward and when the engine rotates in reverse; It is equipped with a charge/discharge control circuit that controls charging and discharging of the capacitor by the output of the ratio generating means, and a voltage detection circuit that detects the voltage of this capacitor.The output of this detection circuit also stops the continuation of engine rotation when the rotation is reversed. It is an object of the present invention to obtain an excellent effect of preventing engine reversal by providing a means for causing the engine to reverse.

Moreover, by combining it with the non-contact ignition device of the relevant engine, it can be expected to have the excellent effect of stopping the ignition function when the engine is reversed.

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

4. The present invention will now be described with reference to the gAl embodiment shown in FIG. 1 is a signal generator, which is composed of a rotary rotor la that rotates C according to the rotation of the engine, a permanent magnet, and a winding part.Due to the shape of the rotor 1a, magnetic flux is generated during forward rotation and reverse rotation. (2) Taking advantage of the fact that the manner of change changes, the time of the positive half-wave and negative half-wave of the AC output is different between the forward rotation and the reverse rotation at 3°C. Reference numeral 2 denotes a waveform shaping circuit, which shapes the waveform of the alternating current output of the signal generator 1. This waveform shaping circuit 2 and the signal generator 1 constitute time ratio generating means.

Next, 3 is a capacitor charging/discharging 111Q11 circuit,
Resistance 301. NOT element 302. ) transistor 303.
304, a resistor 305, a diode 306, transistors 307, 308, 309, 310, a diode 31, and a capacitor 312. Next, 4 is a voltage detection circuit, which includes resistors 401, 402, 403 and a comparator 404.
, resistor 405, transistor 406, resistor 407.4
08. 5 is a means for stopping the engine rotation.

Next, the operation of the above configuration will be explained. For example, as shown in Fig. 1, the rotor la of the signal generator till has a waveform shape such that the way the magnetic flux improves changes during forward rotation and reverse rotation. direction), the waveform becomes as shown in (a) of Fig. 2(A), and during reverse rotation (counter-arrow direction), the waveform appears as shown in Fig. 2(A).
The waveform is as shown in (a) of B), and the time ratio of the positive half wave and the negative half wave of the AC IAt 1g waveform is different between forward rotation and reverse rotation. Follower, C, waveform shaping circuit 2
The output after waveform shaping is shown in Figure 2 (A) and (B) as shown in the (b) waveform.
Waveforms with different time ratios of levels can be obtained. When this shaped output is at L level, the output of NOT element 302 of capacitor charge/discharge circuit 3 is at H level, so transistor 304 is ONL, and transistor 307 is connected to resistor 3.
( ) 5 flows to transistor 304 and not to transistor 309, so transistors 309 and 310 forming a current mirror circuit
Of these, the transistor 310 also has '! l! Current does not flow, the capacitor 12 does not discharge, and instead the transistor 303 via the resistor 301 is connected to the ('l l·゛F-shaped structure), so the current mirror circuit constituted by the transistors 307 and 308 ( 4) Since a current equal to the current 11 flowing from the transistor 307 through the resistor 305 and the I transistor 403 flows through the transistor 308, the capacitor 312 is charged via the diode 306.Next, the output of the waveform shaping circuit 2 When the current is reversed and becomes H level, the current flowing through the transistor 30B stops flowing as a charging current to the capacitor 312 because the transistor 303 is turned ON, and instead, the transistor 304 is turned OFF, so that the current flowing through the transistor 30B is changed from the transistor 307 to the resistor 305. Since a current equal to the current iχ flowing through the transistor 309 that forms a current mirror circuit with the transistor 310 flows through the transistor 310, the charge in the capacitor 312 is discharged.Here, the charge current 11 of the capacitor 312 and the discharge current Since i is determined by the resistor 305 and is almost equal, the charge voltage of capacitor j12 increases as shown in (C) of FIG. Therefore, since the trigger level vT of the comparator (5) 404 determined by the division between the resistors 402 and 403 of the voltage detection circuit 4 is not reached, the comparator 404 as shown in (d) of FIG. 2(A) is not reached. However, as shown in FIG. 2(B)(c), during reverse rotation, the charging period is longer than the discharging period, so the charging voltage of the capacitor 312 gradually increases by -1:. , when the trigger level Vτ of the comparator 404 is finally reached, the second
As shown in (d) of the figure (B), the comparator 404 detects the reversal, and the transistor 406 is
By connecting the resistors 407 and 403 in parallel to provide hysteresis to the detection level VT of comparison &404, the engine rotation stopping means 5 can be operated to stop the engine from continuing to reverse. The means for stopping the engine rotation may be a conventionally known means such as shorting the 141T connector of the ignition system, or it may be possible to operate a fuel blocking valve ring that blocks the supply of fuel to the engine.

Next, a 1182 embodiment of the present invention will be described with reference to an electric circuit diagram shown in FIG. 183. 12 An example is a case in which a reversal prevention device is applied to an ignition device for an internal combustion engine. This waveform shaping output and the detection output of the voltage detection circuit 4 are applied to the OR circuit 6, and the logical sum output controls the transistor 7 which intermittents the primary current of the ignition coil 8 of the internal combustion engine ignition system. Since the output of the voltage detection circuit 4 is always at L level, the transistor 7 is intermittent due to the waveform shaping output itself, and the ignition coil 8 generates an ignition spark, but when the engine reverses, the detection circuit 4 emits an H level signal. When this occurs, the transistor 7 becomes conductive regardless of the waveform shaping output, and no ignition spark is generated in the ignition coil 8.

In each of the embodiments described below, the signal generating side 1 and the waveform shaping circuit 2 are used as a means for generating the time ratio, and the time of the positive half wave and the negative half wave are different during forward rotation and reverse rotation. However, the combination is not limited to this, for example, as shown in FIG. A signal generating side 1' (7) is provided, and each signal is sent to the flip-flop circuit 9's cell 511.
By using a reset input, the same effect can be achieved by utilizing the fact that the time ratio between the H level and L level of the output of the solid block circuit 9 changes during forward rotation and reverse rotation.The point is that the time ratio between forward rotation and reverse rotation changes. The same effect can be obtained by using any means that generates signals with different ratios.

In addition, in each of the embodiments described above, a case was explained in which the charging and discharging current of the capacitor is charged and discharged at a constant current using a current mirror circuit, and the charging current and the discharging current are almost equal to each other. For example, if the time ratio between the output 14 level and the L level after waveform shaping of the ifi generator electric power can be made sufficiently large, the current charging current and the current discharging current can be set to different values accordingly. It is clear that the same effect can be obtained with C. In addition, the same effect 1 can be expected not only by constant current charging and discharging but also by charging and discharging using the R C' time constant via a resistor.

In addition, in each implementation/example described in 1-1, an example was described in which the charging voltage of the capacitor 312 is increased during reverse rotation and t reversal is not detected (8), but this is not limited to this; Needless to say, the reversal may be detected by increasing the charging voltage of the capacitor 312 and since the charging voltage of the capacitor does not reach a predetermined potential during the reversal.

As described above, in the present invention, H level and L level signals are generated according to the rotation of the internal combustion engine, and the time ratio between the I level and the L level is different between forward rotation and reverse rotation. a capacitor charging/discharging control circuit that controls charging and discharging of the capacitor based on the output of the time ratio generating means; a voltage detection circuit that detects the charging voltage of the capacitor; and a voltage detection circuit that operates based on the output of the voltage detection circuit. Since it is equipped with a means to stop engine rotation, it is possible to detect reversal without contact, unlike conventional reversal prevention that relies on mechanical structures, which is expected to have the excellent effect of providing a highly reliable reversal prevention device. can.

Furthermore, the signal generator is rotated in synchronization with the engine to obtain its waveform-shaped output, and the ignition coil intermittent means is operated by the logical output (9) of the signal of the voltage detection output and this waveform-shaped output. In this way, we can expect the excellent effect of being able to provide a non-contact ignition device that is extremely inexpensive and has a highly reliable reverse rotation prevention function.

[Brief explanation of drawings]

FIG. 1 is an electrical circuit diagram showing a first embodiment of the present invention,
2(A) and 2(B) are operation waveform diagrams of each part, FIG. 12(A) shows the operating waveform when the engine rotates in the normal direction, and FIG. 2(B) shows the operating waveform when the engine rotates in the reverse direction. FIG. 3 is an electrical circuit diagram showing a second embodiment of the present invention. FIG. 4 is an electrical circuit diagram showing another implementation of the a-interval generation means applied to the present invention. 1.2... Signal generator and waveform shaping circuit constituting time ratio generating means, 3... Capacitor charge/discharge control circuit, 4.
... Voltage detection circuit, 5... Engine rotation stop means, -6.
...OR circuit. Representative Patent Attorney Takashi Okabe (10)

Claims (1)

[Claims] (11) Generates high-level and low-level signals according to the rotation of the internal combustion engine, and generates a time ratio in which the time ratio of the high level and low level is different depending on when the engine rotates forward and when the engine rotates in reverse. a capacitor charging/discharging control circuit for controlling charging and discharging of the capacitor by the output of the time ratio generating means; a voltage detection circuit for detecting the charging/discharging voltage of the capacitor; An internal combustion engine reversal prevention device comprising an engine rotation stopping means. (2) The engine rotation stopping means calculates a logic between the output of the bending electromotive voltage detection circuit and the output of the time ratio detection means to prevent the primary rotation of the ignition coil. An internal combustion engine reverse rotation prevention device according to claim 1, which comprises a logic circuit that intermittents current.