KR20040023056A - dowel pin formation in cam whill - Google Patents

Abstract

PURPOSE: Dowel pin formation in a cam wheel is provided to sense the direction of a vehicle by changing a shape of a dowel pin in a cam wheel, and prevent an error of a signal by a noise, thereby accurately controlling an ignition period. CONSTITUTION: A dowel pin(12) installed at a predetermined position of a cam wheel is formed in multi-stages. One side of the dowel pin is chamfered to be detected by a cam sensor(20), distinguishing forward rotation from backward rotation by a basis of a travel direction of a vehicle. If a cam angle signal is detected in multi-stages, and a crank angle tooth is detected, an engine control unit judges that a first cylinder of an engine arrives at a TDC(Top Dead Center) and executes a control sub-routine for an ignition period.

Description

Dowel pin formation in cam whill}

The present invention relates to the structure of the willow pin of the cam wheel of the engine, and more particularly, the shape of the dowel pin formed on the cam wheel is changed to multiple stages, so that the engine is turned off and the output is reduced due to the noise inside and outside the vehicle and the impact of the vehicle. It relates to the structure of the dowel pin of the cam wheel to prevent the.

In electronic control of the engine, information on which angle the current crankshaft phase is at an angle relative to the TDC (Top Dead Center) of cylinder 1 during engine operation is essential and most basic.

However, the TDC time point recognized by the engine control device may deviate from the actual value due to machining and assembly tolerances of the timing related parts and torsion due to rotational motion.

Therefore, when the engine is developed, the engine may be operated in a mass production engine differently from the ignition timing of a standard engine, and the engine performance in the low speed and high load region is developed due to the difference between the actual TDC generated by the mass production deviation of the engine and the TDC recognized by the ECU. Smaller or vice versa knocking occurs and affects engine life.

That is, in the cam for detecting the TDC time point, as shown in FIG. 1, one dowel pin 11 is formed at the end of the cam wheel 10, and the tooth is detected from the cam rotation speed detection sensor. .

Figure 2a is a voltage waveform detected from the cam speed detection sensor, Figure 2b is a normal cam speed signal input to the engine control device.

However, the cam wheel shape as described above has a problem that can not detect the direction according to the rotation direction.

That is, as the cam wheel is formed as shown in FIG. 1, the cam axis does not detect the directionality when the cam axis rotates clockwise or counterclockwise, except that the cam axis rotates and the distance difference between the tooth and the sensor. As you approach, the high (H) signal is farther away and the low (L) signal is detected. Therefore, the vehicle generally runs forward, but when the driver of the manual transmission vehicle pushes the vehicle backward due to an inexperienced clutch operation, it does not detect the engine and the engine is turned off.

In addition, when the engine control device detects one rising signal from the cam rotation speed detection sensor and noise occurs in the detection sensor, the signal is temporarily bounced as shown in FIGS. 2C and 2D to set the setting reference value set in the memory. When the engine control device is turned over, the engine control device determines that the dowel pin 11 provided on the cam wheel 10 is close to the cam speed detection sensor by the noise signal, and commits an error that is caused by the high (H) signal. Synchronization between the crank angle sensor and the cam sensor fails, so that the timing of ignition at the correct timing can not be detected and the engine is turned off or the engine output is reduced.

Accordingly, an object of the present invention is to solve the above problems, to provide a cam wheel shape change that can detect the direction of the vehicle by changing the shape of the willow pin of the cam wheel and solve the signal error problem caused by noise. will be.

1 is a view showing the structure of the conventional willow pin of the cam wheel,

2A is a conventional normal cam wheel output voltage graph,

Figure 2b is a conventional normal cam wheel output signal graph,

Figure 2c is a conventional abnormal cam wheel output voltage graph,

Figure 2d is a conventional abnormal cam wheel output signal graph,

Figure 3 is a view showing the Darby pin of the modified cam wheel according to an embodiment of the present invention.

4A is a diagram illustrating an example of detecting a rotation speed of a cam wheel according to an embodiment of the present invention;

Figure 4b is a graph of the output voltage of the modified cam wheel according to an embodiment of the present invention,

5 is a block diagram of an engine control apparatus according to an embodiment of the present invention;

6 is a flowchart illustrating an operation of an engine control method according to an exemplary embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

DESCRIPTION OF SYMBOLS 10 Cam wheel 11 and 12 Dowel pin 20 Cam rotation speed detection sensor

100: vehicle operation state detection device 110: crank angle detection unit

120: cam angle detection unit 200: engine control device

300: drive device

The present invention for achieving the above object,

In the cam wheel, the dowel pin provided in the cam wheel is characterized in that formed in more than one stage.

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

This embodiment is not intended to limit the scope of the present invention, but is presented by way of example only, the same reference numerals are assigned to the same parts as the conventional configuration in the drawings, and redundant descriptions are omitted.

FIG. 3 is a view illustrating a dowel pin of a modified cam wheel according to an exemplary embodiment of the present invention, and FIG. 4A is a diagram illustrating an example of rotation speed detection of a cam wheel according to an exemplary embodiment of the present invention. 4b is an output voltage graph of a modified cam wheel according to an embodiment of the present invention, FIG. 5 is a block diagram of an engine control apparatus according to an embodiment of the present invention, and FIG. 6 is an engine control method according to an embodiment of the present invention. The operation flowchart is.

FIG. 3 is a view illustrating a dowel pin of a modified cam wheel according to an embodiment of the present invention, wherein the dowel pin 12 is formed in multiple stages at a predetermined position of the cam wheel 10.

In addition, as shown in FIG. 4A, the dowel pin 12 formed in multiple stages at a predetermined position of the cam wheel 10 distinguishes the normal rotation from the reverse rotation based on the driving direction of the vehicle and the cam sensor 20. One side is chamfered so as to be detected by the multi-stage.

FIG. 4B is a cam wheel tooth signal detected and output by the cam sensor 20 according to the rotational change of the cam wheel 10 shown in FIG. 4A, and two rising and two falling signals. If is outputted, it is normal signal.

5 is a block diagram of an engine control apparatus according to an exemplary embodiment of the present invention, which includes a vehicle operating state detection device 100 for detecting a cam sensor signal and a crank angle signal that vary according to a change in an operating state of a vehicle;

If the cam signal and the crank angle signal detected and applied by the vehicle operation state detection device 100 are input, and the cam signal is equal to or greater than a predetermined reference value, when two rising signals of the cam signal are detected, whether the crank angle is detected or not. An engine control device 200 for performing a routine of recognizing cylinder 1 and outputting an ignition control signal accordingly;

According to the ignition control signal output from the engine control device 200 is composed of a drive device 300 for outputting an electrical signal for discharging the ignition spark with the spark plug provided in the cylinder.

The vehicle operating state detecting apparatus 100 includes a crank angle detecting unit 110 for detecting a change in a crank angle which is changed according to a change in an operating state of a vehicle;

Cam angle detection unit 120 for detecting a change in the cam angle changes according to the vehicle operating state changes.

An engine control method having the above configuration will be described with reference to FIG. 6.

When the engine of the vehicle is started, the engine control apparatus 200 initializes all variables used, and as the vehicle is driven, the vehicle operation state detecting apparatus 100 changes according to the change in the vehicle operating state. Detect.

Accordingly, when the engine control device 200 outputs a predetermined control signal to receive the crank angle and cam angle signals detected by the vehicle operation state detection device 100, the vehicle operation state detection device 100 is applied. The crank angle and cam angle detected in synchronization with the control signal are output.

The engine control apparatus 200 receives the crank angle and cam angle signals detected and applied by the vehicle operation state detection apparatus 100, and determines whether the applied cam signal is equal to or greater than a set reference value as shown in FIG. 4B. It is determined (S100, S110).

If the cam signal applied from the vehicle operation state detection apparatus 100 is equal to or greater than a set reference value, the engine control apparatus 200 determines whether there is one rising of each cam signal applied (S120).

When there is only one rising of the cam angle signal applied above, the engine control apparatus 200 determines that noise is input to the applied cam angle signal, and returns to step S100 of inputting a crank angle and a cam angle. (S130).

However, the number of rising of the cam angular signal applied from the vehicle operation state detecting apparatus 100 is equal to the number of multi-stage fins 12 formed on the cam wheel 10 in multiple stages as shown in FIG. When it is determined that the waveform is output, the engine control apparatus 200 determines whether the crank angle tooth is detected and applied from the vehicle operation state detecting apparatus 100 (S140).

In the above, after it is determined that the cam angle signal is detected in multiple stages, when it is determined that the crank angle tooth is detected, the engine control apparatus 200 determines that the engine No. 1 reaches TDC, and the stroke of each cylinder is determined. An ignition timing control subroutine for controlling the ignition timing that fits is performed (S150).

However, if it is determined in step S140 that the crank angle tooth is not detected, the engine control apparatus 200 returns to step S100 of inputting the crank angle and the cam angle.

As a result, by changing the formation of the dowel pins of the cam wheel in multiple stages, accurate ignition timing control can be performed, thereby preventing the engine from turning off and reducing the engine output.

As described above, the present invention changes the shape of the dowel pin of the cam wheel to detect the directionality of the vehicle and solves a signal error problem caused by noise, so that accurate ignition timing control is performed, and the engine is turned off and the engine output is reduced. Can be prevented.

Claims (2)

In the cam wheel, the dowel pin structure provided in the cam wheel is formed in multiple stages. The method of claim 1, wherein the dowel pin is a cam wheel's dowel pin structure comprising one side is chamfered and formed in multiple stages to be detected by the cam sensor by distinguishing the forward and reverse rotation based on the driving direction of the vehicle.