JPH0668252B2 - Cylinder identification device for internal combustion engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine cylinder identification device for performing cylinder identification of a multi-cylinder internal combustion engine.

[Conventional technology]

Generally, a signal synchronized with the rotation of the engine is used to control the ignition timing, fuel injection, etc. of the internal combustion engine. A signal generator that generates such a signal is usually attached to the camshaft of an engine and indirectly detects the rotation of the crankshaft. 13 and 14 show such a rotation signal generator, which shows a rotation signal generator for six cylinders. In the figure,
Reference numeral 1 denotes a cam shaft, which is provided so as to have a rotational speed that is 1/2 of that of the crank shaft. Reference numeral 2 is a rotating disk attached to the cam shaft 1, and has a window 3a for angle signal and a window 3b for reference signal which will be described later. 4a, 4b and 5a, 5b are light emitting diodes and photodiodes provided corresponding to the positions of these windows 3a, 3b.
The a and 4b and the photodiodes 5a and 5b are arranged so as to face each other with the rotary disc 2 interposed therebetween. Further, 6a and 6b are amplifier circuits connected to the output terminals of the photodiodes 5a and 5b, respectively, and 7a and 7b are open collector output transistors connected to the output terminals of the amplifier circuits 6a and 6b. ~ Rotation signal generator 8 by output transistors 7a, 7b
Is configured.

FIG. 15 is a diagram showing a signal output from such a rotation signal generator 8, where a is an angle signal (POS signal) output from the window 3a side of the rotating disc 2 and b is an output from the window 3b side. Is a reference signal (REF signal) to be generated. That is, the angle signal is a signal that repeats reversal each time the rotary shaft 1 rotates by 1 °, and is used to measure the rotation angle of the crank, and the reference signal is a signal that reverses at a predetermined crank angle for each cylinder. At the same time it is used as a reference signal of the crank angle, the pulse width of the signal is set to 6 different angle widths corresponding to 6 cylinders with 2 rotations of the crankshaft (720 ° CA). It is used to identify each individual cylinder by measuring using a signal. In addition, the rotation signal generator 8
The output signal of the interface circuit 9 is as shown in FIG.
It is input to the microcomputer 10 via and is used for control calculations such as engine ignition timing and fuel injection.

[Problems to be Solved by the Invention]

The conventional cylinder identification device for an internal combustion engine is configured as described above, and the angle signal and the reference signal are output by the rotation signal generator 8 which detects based on the rotation of the cam shaft. However, since the camshaft is driven from the crankshaft by a belt or the like, there is a phase shift between the camshaft and the crankshaft depending on the operating state of the engine, and as a result, the reference signal output from the rotation signal generator 8 is There is a problem that the actual crank angle deviates, and when the operation of the engine is controlled using such a signal, the ignition timing deviates and the desired performance cannot be obtained. Also, in order to prevent deviation from the crank angle, a method of attaching a signal generator to the crankshaft may be considered, but in a 4-cycle engine, the crankshaft makes two revolutions during the process from intake to exhaust, so it is possible to obtain from the crankshaft. Since it is impossible to discriminate each individual cylinder only with the information provided, it is necessary to separately provide a means for discriminating the cylinder.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a cylinder identification device for an internal combustion engine that can perform accurate cylinder identification without deviation from the crank angle.

[Means for Solving the Problems]

A cylinder identification device for an internal combustion engine according to a first aspect of the present invention includes a reference position signal generating means for generating a crank angle reference position signal based on the rotation of a crankshaft, and a half of the rotation of the crankshaft.
Cylinder identification signal generating means for generating a cylinder identification signal based on the rotation of a rotating shaft rotating at a ratio of: and a cylinder for identifying a cylinder by recognizing a signal state of the cylinder identification signal for each generated crank angle reference position signal. And identification means.

According to a second aspect of the present invention, in the first aspect, the cylinder identification signal is set within the generation section of each crank reference position signal, and the signal width is different for each predetermined number of cylinders, and is otherwise set to be the same. Further, the cylinder identifying means identifies the cylinder by measuring the width of the cylinder identifying signal.

In a third aspect based on the first aspect, the cylinder identification signal is set within the generation section of each crank angle reference position signal, and the signal width is different for each predetermined number of cylinders, and there is no signal otherwise. The cylinder identifying means is adapted to identify the cylinder by measuring the width of the cylinder identifying signal.

In a fourth aspect based on the first aspect, the cylinder identification signal is
The crank angle reference position signal is set to be generated in the generation section of the cylinder identification signal, the signal width is different for each predetermined number of cylinders, and the cylinder identification means measures the width of the cylinder identification signal to determine the cylinder. Is to identify.

In a fifth aspect based on the first aspect, the cylinder identification signal is set within the generation section of each crank angle reference position signal, the number of generated signals is different for each predetermined number of cylinders, and is otherwise the same. The cylinder identifying means is configured to identify the cylinder by measuring the number of signal generations of the cylinder identifying signal.

In a sixth aspect based on the first aspect, the cylinder identification signal is set within the generation section of each crank angle reference position signal, the number of generated signals is different for each predetermined number of cylinders, and there is no signal other than that. In addition, the cylinder identifying means identifies the cylinder by measuring the number of signal generations of the cylinder identifying signal.

In a seventh aspect based on the first aspect, the cylinder identification signal is
The crank angle reference position signal is set to be generated within the cylinder identification signal generation section, the number of signal generations differs for each predetermined number of cylinders, and the cylinder identification means measures the number of signal generations of the cylinder identification signal. By this, the cylinder is identified.

[Work]

In the first aspect of the invention, the reference position of each cylinder is detected by the crank angle reference position signal, and the cylinder identification means identifies which cylinder the reference position is. There is no deviation from the crank angle of.

According to the second aspect of the invention, the cylinder identification signals output in the generation sections of the respective crank angle reference position signals have the same signal width, for example, in different intervals of the generation sections, and are otherwise the same. Cylinder identification of each crank angle reference position signal is performed from the signal.

In the third aspect of the invention, the cylinder identification signal output in the generation section of each crank angle reference position signal has, for example, a different signal width for each separation section of the generation section, and the other signals have no signal. Cylinder identification of each crank angle reference position signal is performed from the identification signal.

In the fourth aspect of the invention, the cylinder identification signal is output, for example, for every other signal of the crank angle reference position signal, and the cylinder identification of each crank angle reference position signal is performed based on the signal width of these cylinder identification signals.

In the fifth aspect of the present invention, the cylinder identification signal output in the generation section of each crank angle reference position signal is, for example, the same signal generation number that is different for each separation section of the generation section, and is otherwise the same. Cylinder identification of each crank angle reference position signal is performed from the identification signal.

In the sixth aspect of the present invention, the cylinder identification signal output in the generation section of each crank angle reference position signal is, for example, a different signal generation number for each interval of the generation section, and the other signals are non-signals. Cylinder identification of each crank angle reference position signal is performed from the cylinder identification signal.

In the seventh aspect of the invention, the cylinder identification signal is output for each alternate signal of the crank angle reference position signal, and the cylinder identification of each crank angle reference position signal is performed based on the number of signal generations of these cylinder identification signals.

〔Example〕

FIG. 1 is a diagram showing a rotation signal generator of a cylinder identification device for an internal combustion engine according to first to sixth embodiments of the present invention. In the figure, reference numeral 11 indicates an internal combustion engine, which is a 6-cylinder 4-cycle internal combustion engine. Further, reference numerals 12 and 13 denote a reference position signal generator and a rotation angle signal generator which are provided so as to face a ring gear 14 which is integral with the crankshaft of the engine as shown in FIG.
Each is composed of a sensor of an electromagnetic pickup. Reference numeral 15 is a cylinder identification signal generator provided on the cam shaft of the engine, which is composed of an optical sensor.

FIG. 3 is a signal waveform diagram obtained by shaping the signal output from such a rotation signal generator, showing the first embodiment, and FIG. 3 (a) is a reference position signal generator. Reference position signal output from 12 (hereinafter abbreviated as REF signal), FIG. 3 (b) is a crank angle signal output from rotation angle signal generator 13 (hereinafter abbreviated as POS signal), FIG. c) shows a cylinder identification signal (hereinafter abbreviated as SGC signal) output from the cylinder identification signal generator 15. That is, on the outer peripheral surface of the ring gear 14 facing the reference position signal generator 12, three positions corresponding to predetermined angular positions of each cylinder are generated so that signals for six cylinders are generated by two rotations of the crankshaft (720 ° CA). Is formed on the outer peripheral surface of the ring gear 14 facing the rotation angle signal generator 13 so that the POS signal is output every 2 ° CA. Further, the SGC signal is set so as to be generated between the signals of the respective REF signals, and the signal width thereof is set to be three types of pulses which are different for every interval and the same pulse for the other three intervals. The SGC signal setting position is offset from the REF signal setting position by a predetermined angle, so even if there is a mechanical transmission system error (angular phase error) between the engine crankshaft and cam shaft, the SGC signal is set between the REF signals. The angle margin is secured so that

Next, the cylinder identifying operation will be described with reference to the flowchart of FIG. REF signal, PO output from the above rotation signal generator
The S signal and SGC signal are input to the microcomputer via the interface circuit as in the conventional case. Based on these signals, the microcomputer first sends the SGC between the REF signals.
The signal width of the signal is detected by counting the number of pulses of the POS signal input during the SGC signal “high level” output period (step S1). Next, REF obtained in step S1
The width of the SGC signal between the signals is compared with the cylinder reference pulse plane stored in advance, and the cylinder corresponding to the matched pulse width is determined as the currently identified cylinder (step S2). Then, the register of the determined presently identified cylinder is set (step S3). For cylinders having the same pulse width, the discrimination cylinder of this time is determined from the discrimination cylinder of the previous time.

As described above, in the first embodiment, since the REF signal corresponding to the reference angular position of each cylinder of the engine is output based on the rotation of the crankshaft, it is for highly accurate engine control without phase shift from the crankshaft. The signal is obtained. Further, since the signal width of the SGC signal which is the cylinder identifying signal only needs to be four types, the signal width can be easily identified, and therefore the signal width accuracy can be relaxed.

FIG. 5 is a waveform diagram of a signal obtained by shaping the output signal of the rotation signal generator according to the second embodiment. In the second embodiment, as in the first embodiment, the reference position signal generator 12 and the rotation angle signal generator 13 are provided so as to face the ring gear 14, and the cylinder identification signal generator 15 is provided on the cam shaft. However, it is different in that the cylinder identification signal generator 15 is constituted by a Hall sensor and the SGC signal is generated at every interval of each REF signal. That is, in this embodiment, the REF signal and the POS signal are the same as those in the first embodiment, but the SGC signal has three kinds of signal widths which are different for each interval of each REF signal as shown in FIG. 5 (c). It is configured so that it is generated and no signal is generated otherwise.

The cylinder identifying operation of the cylinder identifying apparatus for the internal combustion engine configured as described above is performed in the same manner as the operation shown in the flowchart of FIG. 4, and when there is no SGC signal, the cylinder identifying this time is performed from the previous cylinder identifying result.

In the second embodiment, as described above, the signal width of the SGC signal is 3 types and 1/2 of the number of cylinders, so that the signal width accuracy can be further relaxed, and therefore the cylinder identification signal generator 15 can be used. Not only the optical sensor but also an inexpensive Hall sensor, which has relatively low accuracy and resolution, can be used.

FIG. 6 is a waveform diagram showing a signal form of the rotation signal generator according to the third embodiment. In this third embodiment, the REF signal and P
The OS signal is the same as in the first and second embodiments, but the generation form of the SGC signal is different. That is, the SGC signal is set such that its level alternates between a high level and a low level each time each REF signal is generated, and a high level is output for each alternate cylinder of the REF signal corresponding to each cylinder. In addition, there are three types with different signal widths. Also in this embodiment, since the start and end of the SGC signal are set at positions separated by a predetermined angle from the crank angle reference position (REF signal start end), the angular margin with respect to the angle phase between the crankshaft and the camshaft is set. Is secured. Also in this embodiment, the cylinder identification signal generator 15 is composed of a Hall sensor.

Next, the cylinder identifying operation in the third embodiment will be described with reference to the flowchart in FIG. First, in step S11, the signal width of the SGC signal when the REF signal is generated is detected by counting the number of pulses of the POS signal input during the SGC signal high level output period. Next, SGC obtained in step S11
By comparing the width of the signal with the cylinder reference pulse width stored in advance, the cylinder corresponding to the matched pulse width is determined to be the currently identified cylinder (step S12), and the REF generated in the low level output section of the SGC signal immediately after that. When the signal is detected, the cylinder identified this time is set in the register (step S13). Further, at the time when the REF signal generated in the next SGC signal high level output period is detected, by changing the value of the register by a predetermined value, the cylinder is identified this time and at the same time.
The pulse width of the SGC signal high level period is measured at the same time, and the process returns to step S11. By repeating the above operation, it is possible to always identify each cylinder.

In the third embodiment, the pulse width of the high-belt signal section of the SGC signal is used as the cylinder identification means. However, even if the pulse width of the low-level signal section or both of them is used, the same identification can be performed. It is possible.

In the first to third embodiments, the SGC signal width is detected by counting the number of pulses of the POS signal, but the SGC signal width cycle relative to the cycle of the REF signal section without using the POS signal. The same effect can be obtained even if the cycle corresponding to the signal width is detected by measuring the ratio and the cylinder with this cycle ratio is used to determine the cylinder to be identified this time.

FIG. 8 is a signal waveform diagram of the rotation signal generator according to the fourth embodiment. In the fourth embodiment, the SGC signals generated between the REF signals are set to have different pulse numbers in every other section, and the same pulse number is set in the other sections. It is a point. That is, the number of pulses of the SGC signal generated is 2, 3 or 4 different in each interval, and is 1 in other intervals. Also, SGC
The cylinder identification signal generator 15 that generates a signal is composed of a sensor of an electromagnetic pickup.

Next, the cylinder identifying operation of the fourth embodiment will be described with reference to the flowchart of FIG. First, in step S21, the number of SGC signal pulses between REF signals is counted. Next, this count value is compared with the cylinder reference pulse number stored in advance in step S22, and the cylinder corresponding to the matched pulse number is determined as the currently identified cylinder. Then, the identified cylinder determined in step S23 is set in the register. Further, for cylinders having the same pulse number, the current cylinder is derived from the previous cylinder identification result.

FIG. 10 is a waveform diagram showing an output signal of the rotation signal generator according to the fifth embodiment. In this embodiment, the SGC signal has a different number of pulses for each interval between REF signals, and there is no signal in other intervals. That is, the number of pulses of the SGC signal is set to be 1, 2, and 3 in every other section. The cylinder identification signal generator 15 is composed of an electromagnetic pickup sensor. The cylinder identifying operation is performed by counting the number of pulses of the SGC signal between the REF signals as in the fourth embodiment, and in the no signal section, the current cylinder is derived from the previous cylinder identifying result. As described above, in the fifth embodiment, since the number of pulses is half the number of cylinders, it is easy to identify the number of pulses and the signal accuracy can be further relaxed.

FIG. 11 is a waveform diagram showing an output signal of the rotation signal generator according to the sixth embodiment. In this embodiment, the SGC signal is set so that its level alternates between a high level and a low level each time the REF signal is generated, and the REF signal generated when the SGC signal is at the low level, that is, for each alternate cylinder. REF
The number of SGC signal pulses for each section specified by the signal
It is set to a different value from 2, 3 and 4. The initial pulse width of each SGC signal is set to be different. Further, as the cylinder identification signal generator 15, an electromagnetic pickup is used as in the above fourth and fifth embodiments.

Next, the cylinder identifying operation of the sixth embodiment will be described with reference to the flowchart of FIG. First, in step S31, the number of pulses of the SGC signal in the section defined by the REF signal when the SGC signal is low level is counted. Next, the counted pulse number is compared with the cylinder reference pulse number stored in advance in step S32, and the cylinder corresponding to the matched pulse number is determined as the currently identified cylinder. Then, in step S33, the cylinder identified this time is set in the register when the REF signal generated during the low level output period of the SGC signal immediately after is detected. Further SGC
At the time when the REF signal generated during the signal high level output period is detected, the value of the register is changed by a predetermined value to determine the cylinder to be identified this time. Also at this time
The number of SGC signal pulses is also measured at the same time, and control is returned to step S31.

As described above, in the sixth embodiment, since the signal mode of the SGC signal is alternately changed for each REF signal, the cylinder group can be immediately identified.

In the sixth embodiment, the cylinder identification is performed by counting the number of pulses of the SGC signal in the section defined by the REF signal generated during the low level section of the SGC signal, but the logic of the level of the SGC signal is used. It is possible to perform the same discrimination by inverting, and counting the number of pulses in the section defined by the REF signal generated in the high-level signal section. Further, although the signal rising points of the three types of SGC signals are set to be different from the rising points of the REF signal, the rising points of these SGC signals may be equal to the REF signal position.

Further, in the above fourth to sixth embodiments, the cylinder identification is performed by counting the number of pulses of the SGC signal. Therefore, the load on the hardware of the microcomputer can be reduced as compared with the case of using the pulse width of the SGC signal. it can.

Furthermore, in the first to sixth embodiments, when the pulse width (number) of the SGC signal is compared with the reference signal width (number), if the value is other than the specified reference signal width (number), The cylinder of this time (out of specification) is derived from the cylinder corresponding to the detection of the specified (regular) pulse width (number) before that cylinder.

In each of the above embodiments, the cam shaft is used as the rotary shaft that rotates at a ratio of 1/2 to the rotation of the crank shaft, but the present invention is not limited to this, and for example, the rotary shaft of the ignition distributor, etc. Various rotary shafts can be used.

〔The invention's effect〕

As described above, according to the cylinder identification device for an internal combustion engine of the present invention, an axis that rotates at a ratio of 1/2 of the crankshaft for each output signal of the reference position signal generating means that generates a signal based on the rotation of the crankshaft. Since the cylinders are identified by recognizing the signal state of the cylinder identification signal generating means that generates a signal based on the rotation of the cylinder, there is an effect that accurate cylinder identification can be performed without deviation from the crank angle.

[Brief description of drawings]

FIG. 1 is a block diagram of a cylinder identification device for an internal combustion engine according to the present invention, FIG. 2 is a perspective view showing a reference position signal generator and a rotation angle signal generator of the cylinder identification device for the internal combustion engine, and FIG. FIG. 4 is a signal waveform diagram of the rotation signal generator according to the first embodiment, FIG. 4 is a flow chart showing a cylinder identifying operation of the first embodiment,
FIG. 5 is a signal waveform diagram of the rotation signal generator according to the second embodiment, FIG. 6 is a signal waveform diagram of the rotation signal generator according to the third embodiment, and FIG. 7 is a cylinder identification of the third embodiment. FIG. 8 is a flow chart showing the operation, FIG. 8 is a signal waveform diagram of the rotation signal generator according to the fourth embodiment, FIG. 9 is a flow chart showing the cylinder identifying operation of the fourth embodiment, and FIG. 10 is the fifth embodiment. 11 is a signal waveform diagram of the rotation signal generator according to the sixth embodiment, FIG. 11 is a signal waveform diagram of the rotation signal generator according to the sixth embodiment, FIG. 12 is a flowchart showing the cylinder identifying operation of the sixth embodiment, and FIG. A configuration diagram of a rotation signal generator in a cylinder identification device of a conventional internal combustion engine, FIG. 14 is a circuit diagram of the rotation signal generator, FIG. 15 is a signal waveform diagram of the rotation signal generator, FIG. 16 is a conventional and 1 is a block diagram of a cylinder identification device for an internal combustion engine according to the present invention. 11 …… Internal combustion engine, 12 …… Reference position signal generator, 15 …… Cylinder identification signal generator. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (7)

[Claims] 1. A reference position signal generating means for generating a predetermined crank angle reference position signal corresponding to a rotation angle of a crankshaft of an internal combustion engine, and a rotation shaft rotating at a ratio of 1/2 to the rotation of the crankshaft. By identifying the signal state of the cylinder identification signal generation means for each output signal of the reference position signal generation means, cylinder identification signal generation means for generating a cylinder identification signal corresponding to each cylinder of the internal combustion engine A cylinder identification device for an internal combustion engine, comprising a cylinder identification means for identifying a cylinder. 2. Cylinder identification means identifies a cylinder by measuring the width of the cylinder identification signal, and the cylinder identification signal is set within the generation section of each crank angle reference position signal, and for each predetermined number of cylinders. 2. The cylinder identification device for an internal combustion engine according to claim 1, wherein the signal widths of the cylinders are different, and the signal widths of the cylinders other than the predetermined number of cylinders are set to be the same. 3. A cylinder identifying means identifies a cylinder by measuring a width of the cylinder identifying signal, and the cylinder identifying signal is set within a generation section of each crank angle reference position signal and at a predetermined number of cylinders. 2. The cylinder identification device for an internal combustion engine according to claim 1, wherein the signal widths of the cylinders are different, and the cylinders other than the predetermined number of cylinders have no signal. 4. The cylinder identifying means identifies the cylinder by measuring the width of the cylinder identifying signal, and the cylinder identifying signal has a different signal width for each predetermined number of cylinders, and the crank is included in the section where the cylinder identifying signal is generated. 2. The cylinder identification device for an internal combustion engine according to claim 1, wherein the cylinder reference position signal is set so as to be generated. 5. A cylinder identifying means identifies a cylinder by measuring the number of occurrences of the cylinder identifying signal, and the cylinder identifying signal is set within the generation section of each crank angle reference position signal, and the cylinder identifying is performed. 2. The cylinder discriminating apparatus for an internal combustion engine according to claim 1, wherein the signals differ in the number of signal generations for each predetermined number of cylinders, and the number of signal generations of cylinders other than the predetermined number of cylinders is set to be the same. 6. Cylinder identification means identifies a cylinder by measuring the number of occurrences of a cylinder identification signal, and the cylinder identification signal is set within the generation section of each crank angle reference position signal, and the cylinder identification is performed. 2. The cylinder identification device for an internal combustion engine according to claim 1, wherein the signals differ in the number of signals generated for each predetermined number of cylinders, and cylinders other than the predetermined number of cylinders have no signal. 7. A cylinder identifying means identifies a cylinder by measuring the number of occurrences of a cylinder identification signal, and the cylinder identification signals differ in the number of signals generated for each predetermined number of cylinders, and the signal generation for each predetermined number of cylinders. A cylinder identification device for an internal combustion engine, wherein a crank angle reference position signal is set to be generated in a section.