JPH05133267A - Cylinder discriminating device for internal combustion engine - Google Patents

Abstract

PURPOSE:To accurately and quickly discriminate respective cylinders, and easily install a device by generating pulse trains in the permutations and combinations by which the firing orders are different from each other between the respective successive cylinders at specified crank-positions in the respective cylinders of an internal combustion engine. CONSTITUTION:A first pulse generating means 1 generates reference pulses at specified crank-positions in respective cylinders of an internal combustion engine. A second pulse generating means 2 generates pulse trains in the permutations and combinations by which the firing orders are different from each other between the respective successive cylinders, between reference pulses. Further, a pulse train counting means 3 counts the pulse trains the reference pulses. Besides, a cylinder discriminating means 4 discriminates the cylinders from the permutations and combinations of the pulse trains. Thus, the respective cylinders of the internal combustion engine are accurately and quickly discriminated, and a device is easily installed without being restricted by layout of the camshaft side, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for discriminating cylinders of an internal combustion engine.

[0002]

2. Description of the Related Art In an internal combustion engine, in order to identify each cylinder and perform ignition timing control, fuel injection control, etc., a timing plate that rotates in synchronization with the engine is provided, and a projection (or slit) formed on the timing plate passes through. Each time the sensor is turned on, a discrimination signal is output from a sensor such as an electromagnetic pickup (or an optical sensor).

In this case, there is a method in which a plurality of protrusions are formed at a compression top dead center position or the like of a specific cylinder, and the positions of the respective cylinders are sequentially determined with reference to a pulse signal when the protrusions pass.

Further, there is one in which projections for 1 to the number of cylinders are sequentially formed at predetermined crank positions of each cylinder, and the position of each cylinder is discriminated from the number of pulses thereof (Japanese Patent Laid-Open No. 55-64156, etc.). reference).

[0005]

However, in the case where the discrimination is performed in order based on a specific cylinder, the engine needs to make at least one revolution before the discrimination.
For this reason, there is a drawback that the determination is delayed when the engine is started and the startup is delayed.

Further, when the protrusions corresponding to the number of cylinders are provided, the detection pitch becomes small, so that an expensive sensor with good performance must be used. Moreover, with such a detection device, the sensor itself becomes large, and therefore, when it is provided on the camshaft side, there is a problem that installation is difficult due to the layout.

The present invention aims to solve such problems.

[0008]

The present invention, as shown in FIG. 1, includes first pulse generating means 1 for generating a reference pulse at a predetermined crank position of each cylinder of an engine, and ignition between the reference pulses. The second pulse generating means 2 for generating a pulse train having a different permutation combination between the consecutive cylinders, the pulse train counting means 3 for counting the pulse train between the reference pulses, and the cylinder discrimination from the permutation combination of the pulse trains. And a discriminating means 4 for performing the discrimination.

[0009]

Therefore, the next cylinder is discriminated and early discriminated from the permuted combination of the pulse trains emitted at the predetermined crank position of the previous cylinder and the pulse trains emitted at the predetermined crank position of the current cylinder in the ignition order.

Further, since the cylinder is discriminated from the permutation combination of the pulse trains, the number of pulses emitted in each cylinder is less than half the number of cylinders, and a predetermined pitch is secured.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the timing plate 13 is attached to the drive plate 12 provided on the crankshaft 11 of the engine 10, and the timing plate 1
A reference position sensor 14 is provided on the side of 3, and a rotation angle sensor 15 is provided on the outer peripheral side.

Corresponding to the reference position sensor 14, a protrusion 16 is provided on a side portion of the timing plate 13 at a predetermined position before the compression top dead center of each cylinder, and the reference position sensor is provided each time the protrusion 16 passes. A reference pulse is output from 14.

On the outer peripheral portion of the timing plate 13, teeth 17 are cut for each unit angle, and a unit pulse is output from the rotation angle sensor 15 in accordance with the rotation.

On the other hand, the cam sprocket 19 of the camshaft 18 which is connected to the crankshaft 11 via a timing belt and the like also serves as a timing plate, and the cylinder discrimination sensor 20 is arranged on the side of the cam sprocket 19.

Reference position sensor 14, rotation angle sensor 15,
An electromagnetic pickup is used as the cylinder discrimination sensor 20.

On the side of the cam sprocket 19, there are provided a number of projections 21 (in combination with the sensor 20 and pulse generating means) for obtaining a predetermined permutation between consecutive reference pulses output from the reference position sensor 14. When the projection 21 passes through, the cylinder discrimination sensor 20 outputs a pulse, that is, the cylinder discrimination sensor 20 outputs a pulse train of a different permutation combination between the cylinders that are consecutive in the output order of the reference pulse. It is like this.

As shown in FIG. 3, in the case of a 6-cylinder engine,
A predetermined crank position θ ₁ from the reference position sensor 14 to the compression top dead center (TDC) of each of the cylinders # 1 to # 6 (ignition order).
The position of each protrusion 16 is determined so as to generate a reference pulse, and the pulses generated from the cylinder discrimination sensor 20 are continuous cylinders # 1 to # 2, # 2 to # 3, respectively.
Six types of permutation combinations in which the combination of the number of pulses between # 3 to # 4, # 4 to # 5, ... # 6 to # 1 corresponds to the number of cylinders, for example, 1 → 2,2 → 2,2 → 1 , 1 → 3, ... 1
→ 1 to 3 projections 21 that are less than half the number of cylinders are set between each reference pulse so as to be 1.

The pulse from the cylinder discrimination sensor 20 is generated at a constant timing θ ₂ and a constant interval θp from the generation of the reference pulse, and before the generation of the next reference pulse by θ.
Set to open ₃ or more.

Based on the pulse signals of the reference position sensor 14 and the cylinder discrimination sensor 20, a control circuit (cylinder discrimination means) 22 is provided.
Performs cylinder discrimination.

When the reference pulse is input from the reference position sensor 14 as shown in FIG. 4, the control circuit 22 resets the cylinder discrimination counter and counts the pulses input from the cylinder discrimination sensor 20 (steps 101 to 103). ).

Next, when a reference pulse is input from the reference position sensor 14, the cylinder discrimination counter is stopped and the count value is stored (steps 104, 105).

The cylinder discrimination counter is stopped and reset at the same time, and the previous count value and the present count value are stored for each input of the reference pulse.

Then, the combination of the number of the previous count value and the number of the present count value is compared with the permutation identification value of the cylinder to determine the cylinder at the time of inputting the next reference pulse (steps 106 and 107).

In FIG. 3, the previous count value is 1,
When the current count value is 2, the # 2 cylinder is determined. When the last count value is 2, the # 3 cylinder is determined when the current count value is 2.

As described above, since the cylinder is discriminated by the permutation combination of the pulses between the consecutive cylinders, the next cylinder can be discriminated accurately before the first revolution in a 6-cylinder engine, for example, in a short period of time.

Therefore, the cylinder discrimination is not delayed when the engine is started, the ignition timing and the fuel injection can be properly controlled from the beginning of the engine, and a quick start can be ensured.

Further, since the cylinder is discriminated from the permutation combination of the pulses, the number of pulses emitted in each cylinder is less than half of the number of cylinders, so that the detection pitch of the protrusions 21 can be sufficiently set.

Therefore, an expensive sensor is unnecessary,
Even if the number of cylinders is large, the camshaft side can be easily installed without being restricted by the layout.

Although electromagnetic pickups are used for the sensors 14 and 20, optical sensors may be used to form slits instead of the protrusions 16 and 21.

[0031]

As described above, according to the present invention, a pulse train having a different permutation combination is generated at a predetermined crank position of each cylinder of an engine between cylinders having consecutive ignition sequences, and the cylinders are selected from the permutation combination of the pulse trains. Since each cylinder can be accurately discriminated at an early stage, the device can be easily installed without being restricted by the layout of the camshaft side or the like.

[Brief description of drawings]

FIG. 1 is a block diagram of the invention.

FIG. 2 is a configuration layout diagram.

FIG. 3 is a characteristic diagram showing a pulse setting example.

FIG. 4 is a flowchart of a cylinder discrimination process.

[Explanation of symbols]

 11 Crankshaft 13 Timing Plate 14 Reference Position Sensor 16 Protrusion 18 Camshaft 19 Cam Sprocket 20 Cylinder Discrimination Sensor 21 Protrusion 22 Control Circuit

Claims (1)

[Claims] 1. A first pulse generating means for generating a reference pulse at a predetermined crank position of each cylinder of an engine, and a pulse train which is a different permutation combination between the cylinders whose ignition sequence is continuous between the reference pulses. A cylinder discriminating apparatus for an internal combustion engine, comprising: a second pulse generating means for generating a pulse train; a pulse train counting means for counting a pulse train between reference pulses; and a discriminating means for discriminating a cylinder from a permutation combination of the pulse trains.