JPH0212309Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an engine ignition device suitable for a multi-cylinder engine, particularly a 4-cycle multi-cylinder engine with two or more cylinders.

(Problems to be Solved by the Invention) Conventionally, this type of engine has the disadvantage that the air-fuel mixture is ignited at the time of startup without being properly sucked and compressed, which tends to cause smoldering in the combustion chamber.

(Means for Solving the Problems) The object of the present invention is to provide a device that eliminates such inconveniences. a crankshaft angle signal generating means for generating a crankshaft angle signal; and a stopping means for stopping the ignition operation of the ignition circuit when the engine is started; the stopping means includes a counter circuit for counting the crankshaft angle signal; and a muting circuit for stopping the rotation of the crankshaft, and the muting circuit is characterized in that it is disabled by the output of the counter circuit when the count value of the counter circuit matches the count value of at least one revolution of the crankshaft.

(Function) Since the ignition operation of the ignition circuit when starting the engine is stopped by the mutating circuit of the stopping means until the crankshaft has rotated at least one revolution, the intake air compression must pass through the exhaust process during that time. Later ignition is given. Therefore, smoldering within the combustion chamber during startup is prevented as much as possible.

(Example) Next, an example of implementing the present invention will be explained with reference to attached drawings.

The drawing shows an embodiment in which the present invention is applied to a four-cycle two-cylinder engine. In the drawing, 1 is an ignition circuit equipped with an ignition coil 2 on the output side.
The pulse from the ignition pulser 4 that cooperates with the crankshaft turns on the switching element 5 at a predetermined phase for each revolution of the crankshaft, that is, energizes the primary side of the ignition coil 2 connected in series with the switching element 5. It is configured as follows.

On the secondary side of the ignition coil 2, two spark plugs 6, 6 are provided for one cylinder and the other cylinder.
are connected in common, and spark discharge is simultaneously applied to both plugs 6, 6 by energizing the primary side.

In the drawing, 7 indicates a start switch, and the switch 7
When the switch is closed, the starting motor 9 is operated via the relay switch 8, and the engine is started.

Although the above is not different from the conventional one, according to the present invention, a stopping means 10 is provided for stopping the ignition operation of the ignition circuit 1 at the time of starting the engine until the crankshaft is rotated at least one revolution. Spark discharge is applied to both the plugs 6, 6 after one or more rotations.

To explain this in more detail with respect to the illustrated one, the stopping means 10 is a crankshaft angle signal generating means that generates a predetermined number of crankshaft angle signals for one rotation of the crankshaft in synchronization with a predetermined rotation angle of the crankshaft. A counter circuit 12 receives one pulse from the ignition pulser 4 via a waveform shaper 11 for each rotation of the crankshaft, and an output signal from the circuit 12 is input via a latch circuit 13. It is composed of a muting circuit 14 and a one-shot multivibrator 15 which inputs a reset signal to the counter circuit 12 when the start switch 7 is closed, and when the reset signal is input, the output of the counter circuit 12 becomes low level. signal is switched to a high level signal, and according to this high level output signal, the switching element 5 of the ignition circuit 1 is held non-conductive due to the operation of the muting circuit 14, and the ignition operation of the ignition circuit 1 is prevented. Then, when the second pulse is input to the counter circuit 12 when the crankshaft rotates one revolution or more, a low level output signal is generated from the circuit 12, and the muting circuit 14 is inoperative, and the ignition operation is provided by the switching element 5 conducting at the predetermined phase described above.

Next, to explain its operation, in a 4-cycle two-cylinder engine, there is a 360° phase difference between the two cylinders, and when one cylinder is started in a phase state where it is in the intake process and the other cylinder is in the explosion process. There are also cases where one cylinder is started in a phase state where one cylinder is in the compression process and the other cylinder is in the exhaust process. In the former case, normal intake is not performed in the intake process immediately after startup, so If one cylinder that is started is ignited at the end of the compression process following the intake process, smoldering will occur in the combustion chamber, and even in the latter case, one cylinder that is started during the compression process will be ignited at the end of the compression process. If ignition is applied, residual air may ignite and cause smoldering.

However, according to the present invention, as described above, the stopping means 1
0, the ignition operation is stopped until the crankshaft rotates one revolution or more, so in any of the above cases, ignition does not occur at the end of the compression process immediately after startup, and the intake air compression always occurs after the exhaust process. Late ignition is provided to prevent smoldering as described above.

The present invention is applicable not only to a 4-stroke, 2-stroke engine, but also, for example, to a 4-stroke, 4-cylinder engine, in which case one ignition coil is used for every two cylinders.
It is preferable that the ignition operation is applied after the crankshaft has been rotated twice; for example, a low level output is generated upon input of the third pulse after resetting the counter circuit 12 described above. Configure.

Furthermore, when the ignition operation is stopped by the stop means 10, the decompressor 2 may be operated at the same time (not shown).

(Effect of the invention) As described above, according to the present invention, the ignition operation is stopped by the stopping means until the crankshaft is rotated one revolution or more after starting.
This has the effect of preventing residual air in the combustion chamber from being ignited during startup, and preventing the plug from smoldering as much as possible. This is particularly effective in multi-cylinder engines with different ignition timings, as ignition in one cylinder will affect the residual air from other cylinders on the plug, making the plug more likely to smolder.

[Brief explanation of the drawing]

The drawing is a block diagram showing one example of implementing the present invention. 1... Ignition circuit, 10... Stopping means.

Claims (1)

[Claims for Utility Model Registration] (1) Crankshaft angle signal generating means for generating a predetermined number of crankshaft angle signals per crankshaft rotation in synchronization with a predetermined rotation angle of the crankshaft, and ignition at the time of engine startup. A stopping means for stopping the ignition operation of the circuit is provided, and the stopping means includes a counter circuit for counting the crankshaft angle signal and a muting circuit for stopping the ignition operation, and the muting circuit is arranged so that the count value of the counter circuit reaches the crankshaft angle signal. An ignition device for an engine, characterized in that the ignition device is deactivated by the output of the counter circuit when the count value matches the count value of at least one rotation of the shaft. (2) The engine ignition device according to claim 1, wherein the engine is a multi-cylinder engine having at least two or more cylinders with different ignition timings.