JPS621422Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for ensuring safety when starting a vehicle by transmitting the output of an internal combustion engine to drive wheels via a centrifugal clutch.

In vehicles with centrifugal clutches, such as motorized bicycles, if the accelerator is in an accelerating state when the engine is started, the rotation will increase at the same time as the engine starts, and there is a danger that the centrifugal clutch will suddenly engage and the car will fly out. . As shown in Shōjitsu Kaiho No. 53-128428, the ignition operation is performed only when the brake is applied when starting the engine, so that the engine cannot be started unless the brake is applied. A safety device has been proposed. However, this safety device had the problem that if the engine was started without applying the brakes, the spark plug would get wet with raw gas, making it difficult to start the engine and making it impossible for the vehicle to run. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a starting safety device for a vehicle with a centrifugal clutch that prevents the clutch from suddenly engaging when starting the engine without causing difficulty in starting the engine.

The present invention is a starting safety device for a vehicle that transmits the output of an internal combustion engine, which is ignited by an ignition device powered by an exciter coil that induces an alternating current voltage in synchronization with the rotation of the internal combustion engine, to the drive wheels via a centrifugal clutch.
This allows the engine to start without any problems, but prevents the rotational speed from increasing when the engine starts, thereby preventing the centrifugal clutch from suddenly engaging when the engine starts.

Therefore, in the present invention, a series circuit of a current limiting resistor and a starting safety thyristor is connected in parallel to the exciter coil, and the gate of the starting safety thyristor is connected to an exciter so as to give an ignition signal to the starting safety thyristor. The starting safety thyristor is connected to the gate circuit of the starting safety thyristor to turn on and off the starting signal supplied to the starting safety thyristor through the starting signal supply resistor coupled to the coil and the starting safety thyristor to start the internal combustion engine. At times, it is switched to allow an ignition signal to be supplied to the starting safety thyristor through the ignition signal supplying resistor, and when the vehicle is running, the ignition signal is supplied to the starting safety thyristor through the ignition signal supplying resistor. and a start/run selector switch which is switched to prevent the ignition signal from being supplied, and the resistance value of the ignition signal supply resistor is set to be lower than the rotational speed at which the centrifugal clutch is connected and higher than the engine starting rotational speed. It was set so that the voltage induced in the exciter coil at a rotational speed exceeding the specified value would give an ignition signal to the thyristor for starting safety.

With the above configuration, the engine is always started reliably, but at the time of starting, the start travel selector switch allows an ignition signal to be supplied to the thyristor for starting safety through the ignition signal supply resistor. Therefore, when the rotational speed of the engine reaches the set value after the engine is started, the thyristor becomes conductive to stop the ignition operation and prevent the engine rotational speed from exceeding the set value. The set value of this rotational speed is set lower than the rotational speed at which the centrifugal clutch engages and higher than the engine starting rotational speed, so that the engine starts reliably and prevents the centrifugal clutch from engaging at the time of starting. This can prevent the spark plug from getting wet during the starting operation and making it impossible to start the engine.

The present invention will be explained in detail below with reference to the illustrated embodiments.

Fig. 1 shows an embodiment of the present invention, taking as an example a case where a capacitor discharge type ignition device is used as an ignition device for an internal combustion engine. This is an exciter coil placed inside the generator. The exciter coil 1 is for supplying ignition energy to the ignition device. One end of this exciter coil is grounded, and the other end is connected to a capacitor 3 via a diode 2.
connected to one end of the The other end of the capacitor 3 is connected to one end of the primary coil 4a of the ignition coil 4, and the other end of the primary coil 4a is grounded. The anode of a thyristor 5 whose cathode is grounded is connected to one end of the capacitor 3, and a resistor 6 is connected in parallel between the gate and cathode of the thyristor 5. A signal coil 8 provided in a signal generator (not shown) is connected in parallel between the gate cathode of the thyristor 5 via a diode 7, and the signal coil 8 gives an ignition signal to the gate of the thyristor 5 at the ignition position of the engine. It's starting to become easier. A spark plug 9 attached to the cylinder of the engine is connected to the secondary coil 4b of the ignition coil 4, and includes an exciter coil 1, a diode 2, a capacitor 3, an ignition coil 4, a thyristor 5, a resistor 6, a diode 7,
The signal coil 8 and the spark plug 9 constitute a capacitor discharge type ignition device.

The starting safety device of the present invention is provided with a starting safety thyristor in parallel to the exciter coil 1 of the ignition device as described above, and when the starting running selector switch is switched to the starting side, the engine speed exceeds the set rotation speed of the engine. The ignition operation is stopped by giving an ignition signal from the exciter coil to the starting safety thyristor at a rotational speed of 200 to prevent the engine rotational speed from increasing above the rotational speed at which the centrifugal clutch engages. In this embodiment, a current limiting resistor 10 is installed at the connection point between the diode 2 and the capacitor 3.
The anode of the starting safety thyristor 11 is connected through the thyristor 11, and the cathode of this thyristor 11 is grounded. A resistor 12 is connected in parallel between the gate and cathode of the thyristor 11, and a start/run selector switch 13 is connected in parallel to both ends of the resistor 12. Further, an ignition signal supplying resistor 14 is connected between the gate of the thyristor 11 and one end of the exciter coil 1 on the non-grounded side. The starting running selector switch 13 turns on and off the ignition signal supplied to the thyristor for starting safety through the ignition signal supplying resistor. When starting the internal combustion engine, the ignition signal is passed through the ignition signal supplying resistor 14 to the starting safety thyristor 11.
When the vehicle is running, the resistor 1 for supplying the ignition signal is switched to allow the ignition signal to be supplied to the ignition signal.
4 to prevent an ignition signal from being supplied to the starting safety thyristor 11.
Here, the resistance values of resistors 12 and 14 are the same as switch 1.
An engine setting set to a value lower than the rotational speed at which the centrifugal clutch provided between the engine and the drive wheels of the vehicle engages when 3 is open, but higher than the rotational speed at normal startup of the engine. Exciter coil terminal voltage at rotation speeds above rotation speed No.
Vo is selected to give the ignition signal to the thyristor 11.

In the embodiment described above, when starting the engine, the start/travel selector switch 13 is switched to the start side and the switch 13 is left open. When the engine is rotated by the starter in this state, a voltage is induced in the exciter coil 1. When a voltage in the direction of the arrow shown in the figure is induced in the exciter coil 1, the capacitor 3 is charged through the diode 2 to the polarity shown. Next, when an ignition signal is given to the thyristor 5 by the induced voltage in the direction of the arrow shown in the signal coil 8 at the ignition position of the engine, the thyristor 5 becomes conductive and the charge in the capacitor is discharged through the thyristor 5 to the primary coil 4a. . This discharge current causes a large magnetic flux change in the iron core of the ignition coil 4, which induces a high voltage in the secondary coil 4b, causing a spark to occur in the ignition plug 9 and igniting the engine. This starts the engine. As described above, the resistors 14 and 12 are set so as not to apply an ignition signal to the thyristor 11 at the rotation speed at the time of starting the engine, so that the thyristor 11 does not become conductive at the time of starting the engine. Therefore, the engine can be started without any problems. Assuming that the accelerator is set to the increasing speed position when the engine is started, the engine rotational speed will increase after the engine starts, and as shown in Figure 2, the engine rotational speed N will increase. Terminal voltage Ve of exciter coil 1
is rising. When the rotation speed reaches the set value No and the terminal electronic Ve reaches the set value Vo, thyristor 1
An ignition signal is applied to the thyristor 1, which makes the thyristor 11 conductive and discharges the capacitor 3. Since the current limiting resistor 10 is connected in series to the thyristor 11, as shown in the waveform of the terminal voltage Vc of the capacitor 3 in Fig. 3, when the thyristor 11 becomes conductive at an angle θo, the capacitor 3 slowly discharges. do. Therefore, due to the discharge of the capacitor 3 due to conduction of the thyristor 11, no high voltage is induced in the ignition coil 4, and no spark is generated in the ignition plug. Next, at the engine ignition position θi, an ignition signal is given from the signal coil 8 to the thyristor 5, but at this time the capacitor 3 has already been discharged, so
No ignition operation takes place. In this way, when starting the engine, even if the accelerator is on the accelerating side, the ignition operation is stopped when the engine rotational speed reaches the set value, so the engine rotational speed does not exceed the set value. Since the set value of the rotational speed of this engine is set lower than the rotational speed at which the centrifugal clutch engages, it is possible to avoid a dangerous situation where the centrifugal clutch suddenly engages and the vehicle suddenly starts. After starting the engine, start/travel selector switch 13
If the switch is switched to the running side and this switch is closed, the ignition signal will no longer be given to the thyristor 11, so
The engine rotation speed can now be increased in response to accelerator operation, making it possible to drive.

In the above embodiment, the start/run selector switch is connected in parallel between the gate cathode of the thyristor 11. They may be inserted in series. In this case, the start/travel selector switch should be closed on the starting side and opened on the traveling side.

As described above, according to the present invention, a series circuit consisting of a current limiting resistor and a starting safety thyristor is connected in parallel to the exciter coil, and the thyristor is made conductive at a rotational speed higher than a set rotation speed when starting the engine. Since the ignition operation was prevented by
This can prevent the danger of the centrifugal clutch suddenly engaging and causing the vehicle to suddenly start if the accelerator is set to the speed increasing side when the engine is started. In addition, the set value of the rotational speed at which the ignition signal is given to the starting safety thyristor is set higher than the engine starting rotational speed, so there is no problem with engine starting, and the spark plug gets wet and the engine starts. This can prevent inconveniences such as those caused by the inability to do so.

[Brief explanation of the drawing]

Fig. 1 is a connection diagram showing one embodiment of the present invention;
The figure is a diagram showing changes in the terminal voltage of the exciter coil with respect to the rotational speed of the engine, and FIG. 3 is a diagram showing the terminal voltage waveform of the capacitor of the ignition device when the starting safety thyristor is operating. 1...exciter coil, 3...capacitor,
4... Ignition coil, 5... Thyristor, 8... Signal coil, 9... Spark plug, 10... Current limiting resistor,
11...Thyristor for starting safety, 13...Starting/running selector switch, 14...Resistance for supplying ignition signal.

Claims (1)

[Claims for Utility Model Registration] Starting a vehicle by transmitting the output of the internal combustion engine, which is ignited by an ignition device whose power source is an exciter coil that induces an alternating current voltage in synchronization with the rotation of the internal combustion engine, to the driving wheels via a centrifugal clutch. The safety device includes a series circuit of a current limiting resistor and a starting safety thyristor connected in parallel to the exciter coil, and a gate of the starting safety thyristor so as to provide an ignition signal to the starting safety thyristor. an ignition signal supplying resistor coupled to the exciter coil; and a ignition signal supplying resistor connected to the gate circuit of the starting safety thyristor so as to turn on and off the ignition signal supplied to the starting safety thyristor through the ignition signal supplying resistor. When the internal combustion engine is started, switching is made to allow the ignition signal to be supplied to the starting safety thyristor through the ignition signal supplying resistor, and when the vehicle is running, the ignition signal is supplied to the ignition safety thyristor through the ignition signal supplying resistor. and a start/run selector switch that is switched to prevent an ignition signal from being supplied to the start safety thyristor, and the resistance value of the ignition signal supply resistor is greater than the rotational speed at which the centrifugal clutch is engaged. With a centrifugal clutch, characterized in that it is set to give an ignition signal to the starting safety thyristor by a voltage induced in the exciter coil at a rotation speed that is low and above a set value that is higher than the starting rotation speed of the engine. Vehicle starting safety device.