KR100444049B1 - Method of detecting cylinder for engine - Google Patents

Abstract

A cylinder detection method of an engine is disclosed. The disclosed cylinder detection method of an engine includes the steps of: (a) cranking the engine and continuously checking whether the hall sensor becomes low voltage; (b) entering a synchro phase; (c) setting the cylinder counter to 1 and starting fuel injection when the hall sensor is at low voltage in step (b); (d) setting once again to the cylinder counter 1 and determining whether it is checked; (e) entering a resynchro phase if the condition in step (d) is not satisfied; (f) determining whether a fuel cut-off period has been reached; (g) in the step (f), entering the phase into the synchro when the fuel cut off period; (h) restarting the fuel injection; According to the present invention, there is an advantage that the convenience of operation can be provided because the startability is improved.

Description

How to detect cylinder of engine {METHOD OF DETECTING CYLINDER FOR ENGINE}

The present invention relates to a method for detecting a cylinder of an engine, and more particularly, to a method for detecting a cylinder of an engine for improving startability and providing convenience of operation.

In the case of hall sensors, the output voltage is high when the power is turned on regardless of the magnetic field. Noise occurs and the output voltage drops low. This is the same as passing through a hall sensor sensing hole corresponding to cylinder 1, and there is a 50% chance that cylinder 1 will be incorrectly recognized by cylinder 4. 1 illustrates the Hall sensor signal waveform described above.

2 shows a flowchart sequentially showing a cylinder detection method according to the related art.

As shown, the engine is cranked and the Hall sensor signal is monitored for low voltage (steps 10 and 20).

Subsequently, each pulse period pepl_x is measured to find a gap of the crank position sensor (CPS). (Step 30) Each pulse period pepl_x described above is one square wave of the crank sensor. Is the time to complete, shortening `Period-pluse-x`, where` x` is the time sequence, and whether the conditions of pepl <pepl_1 / 2 and pepl_2 <pepl_1 / 2 are satisfied. If it is determined whether or not the condition is satisfied, the aforementioned gap is found (steps 40 and 50).

In addition, it is determined whether the hall sensor is low voltage, and when the low voltage is low, the cylinder counter is set to 1, and this is again checked and the next step is performed depending on whether or not the hall sensor is low.

Then fuel injection starts (step 90).

On the other hand, if the condition of step 60 is not satisfied, the cylinder counter is set to 3 and fuel injection is started (steps 100 and 110).

As described above, the cylinder detection method of the engine according to the related art is a cylinder number (hereinafter referred to as cyl-no) because the hall sensor voltage is triggered low after the CPS gap is detected. Only if the counter is set to 1 (cylinder identification 1), proceed as follows.

Immediately after starting the engine, the section that becomes the low voltage of the hall sensor is continuously checked, and three consecutive pulse cycles (pepl_2, pepl_1, pepl) are checked to find the gap of the CPS immediately after starting. Subsequently, after the CPS gap is found, the Hall sensor voltage is triggered low, and the cylinder counter (cyl-no) is set back to 1 (cylinder recognition), and when the Hall sensor is high, the cylinder counter ( cyl-no) is changed to 4.

However, according to the related art, when the Hall sensor malfunctions at power-on, the crankshaft is further rotated by one more rotation to check the number of cylinders. That's how. This can increase the certainty of cylinder detection by covering the abnormal behavior of the Hall sensor, but again crankshaft when the cylinder counter is set to 1 (bmzzyl 1) (detection of Hall sensor failure). The cylinder delays detection of cylinder 1 while the engine rotates (no fuel injection during this time), which gives a start-up delay. In particular, in the case of a hot start, the driver may feel a start delay, which is pointed out as a problem.

On the other hand, the dotted line in Figure 2 is a process of detecting the cylinder number 1 by the Hall sensor and the CPS, which is defined as a synchro phase (synchro phase). Meanwhile, the synchro, when the engine cranks the The process of determining the cylinder number of the engine using the output. In the case of the four-cylinder engine, the crankshaft rotates two times and all the cylinders complete combustion one time, thus completing one cycle. You will find This process is defined as synchro.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for detecting a cylinder of an engine to improve startability and provide convenience of operation.

1 is a Hall sensor signal waveform diagram.

Figure 2 is a schematic flowchart showing sequentially a cylinder detection method of the engine according to the prior art.

Figure 3 is a schematic flowchart showing sequentially a cylinder detection method of the engine according to the present invention.

The cylinder detection method of the engine of the present invention for achieving the above object comprises the steps of: (a) cranking the engine, and continuously checking whether the hall sensor becomes low voltage; (b) entering a synchro phase; (c) setting the cylinder counter to 1 and starting fuel injection when the hall sensor is at low voltage in step (b); (d) setting once again to the cylinder counter 1 and determining whether it is checked; (e) entering a resynchro phase if the condition in step (d) is not satisfied; (f) determining whether a fuel cut-off period has been reached; (g) in the step (f), entering the phase into the synchro when the fuel cut off period; (h) restarting the fuel injection;

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a schematic flowchart sequentially illustrating a cylinder detection method of an engine according to the present invention.

Referring to the drawings, the cylinder detection method of the engine according to the present invention first cranks the engine and continuously checks whether the hall sensor becomes low voltage (steps 210 and 220).

Then enter the synchro phase, as shown in FIG. 2 (step 230).

In step 230, when the hall sensor is at low voltage, the cylinder counter is set to 1, and the first fuel injection is started (steps 240 and 250).

The cylinder counter 1 is set once again, and it is judged whether or not it is checked (step 260).

If the condition in step 260 is not satisfied, a resynchro phase is entered. In step 270, the synchro cannot trust a synchro already completed due to an abnormal signal such as a cam sensor. In this case, the process of synchronizing is performed again. Next, it is determined whether a fuel cut-off period has been reached (step 280).

When the fuel cut off period is performed in step 280, the process enters the resyncing phase (step 290).

Then, fuel injection is restarted, and the flow (logic) is terminated (step 300).

On the other hand, if the Hall sensor is not at low voltage in step 230, that is, if the Hall sensor is at high voltage, the cylinder counter is set to 3, fuel injection is started and the flow ends (steps 310 and 320).

On the other hand, the synchro phase measures each pulse period pepl_x to find a gap of the CPS, and determines whether or not the conditions of pepl <pepl_1 / 2 and pepl_2 <pepl_1 / 2 are satisfied. If the above condition is satisfied, the above gap is found. And determining whether the hall sensor is low voltage.

In the cylinder detection method of the engine according to the present invention as described above, the section in which the voltage of the hall sensor becomes low immediately after starting is continuously checked, and the synchro phase is entered.

After finding the CPS gap, the Hall sensor voltage is triggered low, so the cylinder counter (cyl-no) is set back to 1 (cylinder recognition 1), and the hall sensor voltage is high. In the case of, change the cylinder counter (cyl-no) to three.

In the above case, fuel injection is performed regardless of whether the cylinder counter (cyl-no) is '1' or '3' (measure to eliminate the start-up delay). After starting, if it is the 1st process, go back to the process and perform the synchro phase again.

Even in this case, if the cylinder number is 1 because the Hall sensor is low, the detection of cylinder No. 1 is abnormal due to the Hall sensor. Fuel injection still continues at this time. This means you are fueling the wrong cylinder.

Subsequently, it is determined whether a fuel cut section (fuel cut non-injection part) has been reached, and if a fuel cut, the fuel cut is turned off, and after 20 revolutions, engine speed> 2000 rpm and engine speed gradient If <300 rpm / sec, start the phase with resync to detect cylinder 1 again. This is for a stable synchro. When fuel cut in, the fuel injection is restarted in the correct cylinder.

As described above, the cylinder detection method of the engine according to the present invention has the following effects.

Accurate cylinder detection prevents start-up and improves driving safety.

And since the startability is improved, the convenience of operation can be provided.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments are possible. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (3)

(a) cranking the engine and continuously checking whether the hall sensor becomes low voltage; (b) entering a synchro phase; (c) setting the cylinder counter to 1 and starting fuel injection when the hall sensor is at low voltage in step (b); (d) setting once again to the cylinder counter 1 and determining whether it is checked; (e) entering a resynchro phase if the condition in step (d) is not satisfied; (f) determining whether a fuel cut-off period has been reached; (g) in the step (f), entering the phase into the synchro when the fuel cut off period; (H) restarting the fuel injection; cylinder detection method of the engine comprising a. The method of claim 1, And in the step (b), if the hall sensor is not at low voltage, setting the cylinder counter to 3 and starting fuel injection. The method of claim 1, The synchro phase, (A) measuring each pulse period pepl_x to find a gap of the CPS; (B) determining whether or not the conditions of pepl <pepl_1 / 2 and pepl_2 <pepl_1 / 2 are satisfied; (C) finding the gap if the condition of step (b) is satisfied; (D) determining whether the hall sensor is at a low voltage; and detecting the cylinder of the engine.