JPH11229948A - Rotation position detector for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a starting characteristic and crank angle detection accuracy by allowing detection of an absolute position of a crank shaft even when an engine is stopped. SOLUTION: Projections 7-10 are arranged on a rotary drum 6 in a crank angle sensor 5, and a combination of the projections 7-10 detected by means of a signal output device 11 is differentiated according to the rotation position of the crank shaft 2. In a rotary plate 18 in a cylinder determination sensor 17, circular arc type projections 19, 20 are arranged, and a combination of the arc type projections 19, 20 detected by means of a cylinder signal output device 21 is differentiated according to the rotation position of a cam shaft 3. Using a position signal from a crank angle sensor 5, a control unit 25 detects an absolute position of the crank shaft 2 so as to perform cylinder determination in compliance with each cylinder 1A of an engine main body 1 according to a cylinder detection signal from the cylinder determination sensor 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine rotational position detecting device which is preferably used for detecting the rotational position of a crankshaft provided in, for example, an automobile engine. The present invention relates to an engine rotational position detecting device configured to detect the rotational position.

[0002]

2. Description of the Related Art Generally, a vehicle engine or the like is provided with a rotational position detecting device for detecting a rotational position of the engine. An engine rotational position detecting device of this type according to the related art includes a metal rotary plate provided on an engine crankshaft and an electromagnetic pickup type rotary sensor provided near the rotary plate. And an angle sensor.

Here, on the outer peripheral side of the rotary plate,
The plurality of protrusions to be detected are, for example, 10 ° in the rotational direction.
They are provided with a certain interval. When each of the projections of the rotating plate passes through the position of the rotation sensor when the crankshaft rotates, the crank angle sensor magnetically detects each of these projections and outputs a position signal (pulse signal) every 10 °. ) Is output to the control unit for engine control.

Further, on the camshaft side of the engine, a cylinder which detects from the rotational position of the camshaft that each cylinder of the engine has reached near the top dead center before the intake stroke, and outputs a cylinder detection signal to the control unit. A discrimination sensor is provided.

During operation of the engine, the control unit determines a cylinder reaching the vicinity of the top dead center using the cylinder detection signal from the cylinder determination sensor, and the crank angle sensor determines the cylinder based on the cylinder detection signal at this time. The number of pulses of the output position signal is counted. Accordingly, the control unit detects the rotational position (crank angle) of the crankshaft, and when the detected value reaches a predetermined injection timing, ignition timing, or the like determined for each cylinder, the fuel injection control and the ignition control are performed. And so on.

[0006]

In the above-mentioned prior art, the crank angle is detected by counting the number of pulses of the position signal output from the crank angle sensor, and a desired crank angle for each cylinder is detected. The fuel injection control and the ignition control are performed.

However, the crank angle sensor merely outputs the same position signal every 10 ° when the crankshaft rotates. To detect the absolute position of the crankshaft, for example, a cylinder detection signal is used. As described above, unless the position signal is counted based on a signal output when the crankshaft reaches a predetermined rotational position, the absolute position of the crankshaft cannot be detected only by this position signal.

Therefore, when the engine is started, the crankshaft rotates to some extent from the previous stop position, and the absolute position of the crankshaft cannot be detected unless the reference signal is output once. There is a problem in that the control timing at the time of starting the engine is delayed, and it is not possible to perform fuel injection control, ignition control, and the like in a short time.

The present invention has been made in view of the above-described problems of the prior art. The present invention can always detect the absolute position of the crankshaft and the like even when the engine is at a stop position, and can improve the detection accuracy of the rotational position. It is another object of the present invention to provide an engine rotational position detecting device that can perform fuel injection control, ignition control, and the like at an early stage when the engine is started, and can improve the startability of the engine.

[0010]

According to a first aspect of the present invention, there is provided a rotating body which is rotated by an output shaft of an engine and is provided with a plurality of detected parts, and wherein a rotating body is provided near the rotating body. And a signal output means for outputting a position signal corresponding to each of the detected portions of the rotating body, wherein each of the detected portions of the rotating body is provided at a predetermined angle. The signal output means includes a plurality of rotation detection sections, each of which is formed on the rotating body with a different shape from each other, and extends along the rotating direction of the rotating body. A configuration is employed in which position signals having different combinations are output for each detection area.

With this configuration, the rotation area of the rotating body can be divided into a plurality of detection areas having different shapes from each other, and the signal output means can output position signals having different combinations for each detection area. Can output. This allows
A detected area corresponding to the position of the signal output means among the detected areas of the rotating body can be identified by a combination of the position signals, and even when the output shaft of the engine is at the stop position, the absolute rotation position is detected. be able to.

Further, in the invention of claim 2, the rotating body comprises a rotating drum provided on an output shaft of an engine, and each of the detected areas is separated from the rotating drum in an axial direction of the rotating drum. A plurality of projections projecting radially from the outer peripheral side and extending in the rotation direction of the rotary drum over a range related to the angle, each rotation detection unit of the signal output unit includes a rotation detection unit for each of the projections. In order to detect the presence / absence of the rotary drum, the rotary drum is provided to be spaced apart in the axial direction.

Thus, the respective projections can be arranged apart from each other in the axial direction of the rotary drum, and the combination of the presence and absence can be different from each other for each detection area. The presence or absence of each projection can be detected by each rotation detection unit of the signal output means, and the signal output means can output position signals having different combinations for each of the detection target areas.

Further, according to the third aspect of the present invention, the rotating body comprises a rotating plate provided on an output shaft of the engine, and each of the detected areas is separated from the rotating plate in a radial direction of the rotating plate. A plurality of projections provided on the surface and extending in an arc shape over the range related to the angle, each rotation detection unit of the signal output means detects the presence or absence of each projection. Therefore, the rotary plate is provided to be spaced apart in the radial direction.

With this arrangement, the respective projections can be arranged apart from each other in the radial direction of the rotary plate, and a position signal having a different combination for each of the detection areas corresponding to the combination with or without the projection is output. Output from the means.

On the other hand, in the invention according to claim 4, the rotating body on the crankshaft side provided on the crankshaft of the engine and having a plurality of detected parts is formed, and each of the rotating bodies provided near the rotating body is provided. In an engine rotational position detecting device including a signal output unit that outputs a position signal corresponding to a detecting unit and a cylinder determining unit that determines a cylinder of the engine, each detected portion of the rotating body is determined in advance. The rotating body is formed in a shape different from each other at every predetermined angle, and is constituted by a plurality of detection areas extending along the rotating direction of the rotating body, and the signal output means has a plurality of rotation detecting units. The position signals having different combinations are output for each of the detected areas, and the cylinder discriminating means is provided at least on the camshaft side of the engine and is different for each cylinder of the engine. Employs a formed by outputting a cylinder detection signal configuration that.

Thus, the absolute position of the crankshaft can be detected by using the position signal from the signal output means, and the cylinder of the engine can be determined by the cylinder detection signal from the cylinder determination means. Injection control, ignition control, and the like can be performed for each cylinder at desired timing.

Further, in the invention of claim 5, the cylinder discriminating means is formed on the rotating plate on the camshaft side which rotates integrally with the camshaft, and on the rotating plate with a number corresponding to the number of cylinders of the engine. A plurality of detection areas having different shapes and extending in the rotation direction of the rotary plate, and a cylinder signal having a plurality of rotation detection units and outputting a different combination of cylinder detection signals for each of the detection areas. And output means.

Thus, the detected area corresponding to the position of the cylinder signal output means among the detected areas provided on the rotating plate on the camshaft side can be identified by the combination of the cylinder detection signals, and the crankshaft is moved to the stop position. Even if there is, the cylinder of the engine can be determined.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An engine rotational position detecting device according to an embodiment of the present invention will be described below in detail with reference to FIGS.

FIGS. 1 to 7 show a first embodiment of the present invention. In this embodiment, a rotational position detecting device of a four-cylinder engine will be described as an example.

Reference numeral 1 denotes an engine body constituting a four-cylinder engine. Each cylinder 1A of the engine body 1 is provided with a fuel injection valve and a spark plug (neither is shown) whose driving is controlled by a control unit 25 described later. Each is provided. Further, the engine body 1 is provided with a crankshaft 2 serving as an output shaft, and a camshaft 3 connected to the crankshaft 2 and making one rotation while the crankshaft 2 makes two rotations.

Reference numeral 4 denotes a starter composed of an electric motor or the like. The starter 4 outputs a start signal shown in FIG. 7 when a driver operates a start switch (not shown) of the vehicle when starting the engine. Thus, the crankshaft 2 is driven to rotate to start (crank) the engine.

Reference numeral 5 denotes a crank angle sensor provided in the vicinity of the crankshaft 2. The crank angle sensor 5 includes a rotating drum 6 described later and a signal output device 1 facing the rotating drum 6.
1 and the like, and is configured to detect the absolute position of the crankshaft 2 as described later.

Reference numeral 6 denotes a rotating drum as a rotating body provided on the crankshaft 2. As shown in FIG. 2, the rotating drum 6 is formed of a magnetic material such as electromagnetic stainless steel into a substantially cylindrical or cylindrical shape. It rotates with the crankshaft 2 in the direction of arrow A. Also, on the outer peripheral side of the rotating drum 6, first, second, third, and fourth projections 7, 8, 9, 10,
Are provided in the axial direction so that the protrusions 7 to 10 protrude radially from the outer peripheral side of the rotary drum 6 with a certain protrusion dimension.

Here, when the fourth projection 10 is configured to extend in the circumferential direction of the rotary drum 6 over a range of an angle θ (for example, 11.25 °), the first projection 7 Are provided symmetrically at an interval of an angle 8θ (for example, 90 °) in the rotation direction, and these are provided with a position signal S shown in FIG.
1 and extends in the rotational direction over the range of the angle 8θ. Further, four second projections 8 are provided at intervals of an angle 4θ (for example, 45 °) in the rotation direction, and these extend in the rotation direction over the range of the angle 4θ corresponding to the position signal S2. .

Further, eight third projections 9 are provided at intervals of an angle 2θ (for example, 25.5 °) in the rotational direction, and these extend over the range of the angle 2θ in accordance with the position signal S3. At the same time, 16 fourth protrusions 10 are provided at intervals of an angle θ in the rotational direction, and these extend over the range of the angle θ corresponding to the position signal S4.

As a result, as shown in FIG. 6, the rotating drum 6 has sixteen detection areas Ri (i = 1, 2, 3) serving as detection sections with respect to its half-circle angle 16θ (180 °). ,…, 16
) Are provided for each angle θ. In each of the detection regions Ri, the projections 7 to 10 are arranged in different combinations, so that the detection regions Ri have different shapes. Similarly, at an angle 16θ (180 °) on the other half circumference side of the rotating drum 6, 16 detection regions Ri are similarly constituted by the projections 7 to 10.

Reference numeral 11 denotes a signal output device as signal output means provided near the rotary drum 6;
As shown in FIG. 4, reference numeral 1 denotes a sensor case 12 extending in the axial direction of the rotary drum 6, and four rotation detecting units 13, 14, 1 provided in the sensor case 12 so as to be spaced apart in the axial direction.
5, 16 and the like, and the rotation detectors 13 to 16 face the outer peripheral side of the rotating drum 6 with a predetermined gap therebetween.

Here, the rotation detecting unit 13 includes the magnet 1
3A and a Hall element 13B, etc., and the presence or absence of each projection 7 is determined by the Hall element 1 according to the rotational position of the rotary drum 6.
3B, it detects magnetically and outputs a first position signal S1 to the control unit 25 in accordance with the detection result. In this case, the output level of the position signal S1 becomes "high level" as shown in FIG. 6 while each projection 7 faces the rotation detection unit 13, and each projection 7 is separated from the rotation detection unit 13. When they are not facing each other,
It switches to "low level".

Similarly, the rotation detectors 14, 15, and 16 also include magnets 14A, 15A, 16A,
4B, 15B, 16B, etc., the rotation detector 14 outputs a second position signal S2 corresponding to the presence or absence of each projection 8, and the rotation detector 15 includes the presence or absence of each projection 9. , And the rotation detecting section 16 outputs a fourth position signal S4 corresponding to the presence or absence of each projection 10.

Thus, the signal output device 11 faces the detected region Ri of each of the detected regions Ri of the rotary drum 6 corresponding to the rotational position of the crankshaft 2, and has the projections 7 to 10 in that region. , Position signals S1 to S4 corresponding to
Is output to the control unit 25. The combination of the output levels of the position signals S1 to S4 is configured to be different for each detection region Ri.

A cylinder discriminating sensor 17 is provided near the camshaft 3 and serves as a cylinder discriminating means. The cylinder discriminating sensor 17 includes a rotating plate 18 to be described later and a cylinder signal output device opposed to the rotating plate 18. 21 for determining the cylinder of the engine.

Numeral 18 denotes a rotary plate provided on the camshaft 3 and made of a magnetic material such as metal. The rotary plate 18 rotates together with the camshaft 3 in the direction of arrow B in FIG. On the surface of the rotating plate 18, first and second arc-shaped projections 19 and 20 arranged concentrically with respect to the center O thereof are provided radially apart from each other. , 20 are rotating plates 18
And project in the axial direction with a predetermined projection dimension.

Here, the first arc-shaped projections 19 extend in a semi-arc shape at an angle of, for example, 180 °. Also,
The second arc-shaped projections 20, 20 are located on the inner peripheral side with respect to the arc-shaped projection 19, extend in the circumferential direction at an angle of, for example, 90 °, and radially oppose each other with the center O of the rotating plate 18 interposed therebetween. ing.

As a result, four cylinder discrimination areas K1, K2, K3, and K4 serving as detection areas are provided on the rotating plate 18 at intervals of 90 ° corresponding to the first to fourth cylinders of the engine. In the cylinder discrimination areas K1 to K4, arc-shaped projections 19 and 2 are provided.
0 are arranged in different combinations.

Also, the boundary lines OL1, L2, OL3, and O between the cylinder discriminating regions K1 to K4.
The position of -L4 is the top dead center (# 1, # 2, ## shown in FIG. 7) at which the first to fourth cylinders of the engine start the intake stroke, respectively.
3, # 4), for example, at a crank angle of 60 °
These positions are set to the near side in the rotation direction by the angle α, and these positions coincide with the positions at which the value of the detection angle C described later is reset to zero.

A cylinder signal output device 21 is provided near the rotary plate 18 as cylinder signal output means. The cylinder signal output device 21 has a sensor case extending in the radial direction of the rotary plate 18 as shown in FIG. 22, and two rotation detecting units 23, 24 and the like provided in the sensor case 22,
The rotation detecting units 23 and 24 are connected to the rotating plate 1 through a certain gap.
8 faces the surface side.

Here, the rotation detectors 23 and 24 are substantially the same as the rotation detectors 13 to 16 of the crank angle sensor 5 and are composed of magnets 23A and 24A and Hall elements 23B and 24B. A first cylinder detection signal Sa shown in FIG. 7 is output in response to the presence or absence of the arc-shaped projection 19, and the rotation detection unit 24 detects the second cylinder in response to the presence or absence of the arc-shaped projection 20. The signal Sb is output.

As a result, the cylinder signal output device 21 faces the cylinder discriminating area corresponding to the rotational position of the camshaft 3 among the cylinder discriminating areas K1 to K4 of the rotary plate 18, and the arc-shaped projections 19 and 20 in that area. The cylinder detection signals Sa and Sb corresponding to the presence / absence of are output to the control unit 25.
The combination of the output levels of the cylinder detection signals Sa and Sb is different from each other for each of the cylinder discrimination areas K1 to K4.

Reference numeral 25 denotes a control unit for controlling the engine. As shown in FIG. 1, the control unit 25 is connected to the input side of the crank angle sensor 5, the cylinder discriminating sensor 17, and the like. A fuel injection valve, a spark plug, and the like provided on the first cylinder are connected to the output side, and control of fuel injection, ignition control, and the like is performed for each of the cylinders 1A.

The storage unit 25A of the control unit 25 stores position signals S1 to S1 from the crank angle sensor 5.
Using the data for updating the detected angle C shown in FIG. 6 using S4 and the cylinder detection signals Sa and Sb from the cylinder discrimination sensor 17, the vicinity of the top dead center of each cylinder of the engine before the intake stroke is used. Are stored in advance.

Here, the detected angle C is calculated by a crank angle determiner whose value corresponds to the absolute rotational position (absolute position) of the crankshaft 2. When the crankshaft 2 makes one rotation, The angle θ (for example, 1) from 0 ° to 180 ° with respect to the half rotation 180 ° in the first half and the second half respectively.
1.25 °).

The operation of the apparatus for detecting the rotational position of the engine according to the present embodiment has the above-described configuration. Next, the operation of the apparatus will be described with reference to FIG.

Here, in FIG. 7, the characteristics from the stop to the start of the engine are shown as the relationship among the cylinder detection signals Sa and Sb, the position signals S1 to S4, the injection signal and the start signal with respect to the crank angle. # 4, # 2, # inside
At the positions # 1 and # 3, the fourth, second, first and third cylinders of the engine reach the top dead center before the intake stroke, respectively, as the crankshaft 2 rotates. 6 and 7
In the engine (crankshaft 2) the fourth
In this example, the cylinder is stopped at a position P1 80 ° before the top dead center of the cylinder and the engine is started from the position P1.

When the driver turns on the ignition key of the vehicle and turns on the power to the crank angle sensor 5, the cylinder discriminating sensor 17, the control unit 25, and the like, the crank angle sensor 5 And the cylinder discriminating sensor 17 similarly outputs cylinder detection signals Sa and Sb corresponding to the rotational position of the camshaft 3 to the control unit 25.

Thus, the control unit 25
Detects the absolute position of the crankshaft 2 using the position signals S1 to S4 from the crank angle sensor 5 and the data for updating the angle, and determines the detected angle C according to the combination of the output levels of the position signals S1 to S4. For example, the angle is updated to the angle C0 in FIG.

The control unit 25 performs the cylinder discrimination of the engine using the cylinder detection signals Sa and Sb from the cylinder discrimination sensor 17 and the data for cylinder discrimination, and when the engine is started from the position P1, the fourth control is performed. The first arrival of the cylinder at the top dead center is detected by a combination of the cylinder detection signals Sa and Sb.

Here, the angle C0 depends on the output level of the cylinder detection signals Sa and Sb, for example, when the output levels of the cylinder detection signals Sa and Sb are the cylinder discrimination areas K4 and
When it corresponds to K1, the angle is located within the range of the first half of one rotation of the crankshaft 2, and when the cylinder detection signals Sa and Sb correspond to the cylinder discrimination areas K2 and K3, The angle is within the range of the latter half rotation. Therefore, the control unit 25 can detect the absolute rotational position of the crankshaft 2 as the angle C0 over substantially one rotation range by using the cylinder detection signals Sa and Sb.

Next, when the driver or the like outputs a start signal to the starter 4 to start the engine, the crankshaft 2 is driven to rotate, so that each detection region R of the rotary drum 6 is driven.
In i, the area facing the signal output device 11 changes, and the value of the detected angle C is updated according to the absolute position of the crankshaft 2.

The control unit 25 determines the fuel injection timing and the ignition timing based on the updated value of the detected angle C, and sends an injection signal to the fuel injection valve of the fourth cylinder when the predetermined injection timing is reached. And when a predetermined ignition timing (for example, position P2 in FIG. 7) is reached,
An ignition signal is output to the ignition plug of the cylinder.

Similarly, when the crankshaft 2 is further rotated, the control unit 25 uses the position signals S 1 to S 4 from the crank angle sensor 5 to detect the detected angle C.
, While performing cylinder discrimination of the second, first, and third cylinders using the cylinder detection signals Sa, Sb from the cylinder discrimination sensor 17, fuel injection control, ignition control, and the like are also performed on these cylinders. Do each, and then start the engine.

Thus, in the present embodiment, the projections 7 to 10 are provided on the rotary drum 6 on the side of the crank angle sensor 5, and the sixteen detection regions Ri are rotated by the projections 7 to 10 in the rotation direction of the rotary drum 6. And arc-shaped projections 19 and 20 are provided on the rotary plate 18 on the cylinder discrimination sensor 17 side, and the four arc-shaped projections 19 and 20 correspond to four cylinder discrimination areas K1 to K4 corresponding to the number of cylinders of the engine. Since K4 is provided so as to extend in the direction of rotation of the rotary plate 18, the absolute position of the crankshaft 2 can be immediately detected by the crank angle sensor 5 when the control unit 25 and the like are turned on when the engine is started. At this time, the cylinder of the engine can also be reliably determined by the cylinder determination sensor 17.

That is, when the engine is started, even if the crankshaft 2 is stopped at an arbitrary rotational position, the absolute position can be detected and the cylinder of the engine can be determined before the crankshaft 2 is driven to rotate. Thus, fuel injection control, ignition control, and the like at the time of engine start can be started early, and the startability of the engine can be reliably improved.

Therefore, in a vehicle equipped with an idle stop control for temporarily stopping the engine when the vehicle is in an idle operation state, or a specification in which the drive source is switched between an electric motor and a gasoline engine according to the operation state of the vehicle. In addition, the engine can be restarted in a short time, and the drivability of the vehicle can be improved.

Further, since it is not necessary to detect the rotational position of the crankshaft 2 based on the cylinder detection signal on the camshaft 3 side as in the prior art, there is no mechanical connection between the crankshaft 2 and the camshaft 3. Even when there is rattling or the like, the rotating drum 6
The absolute position of the crankshaft 2 can always be accurately detected using only the position signals S1 to S4 corresponding to the respective detected regions Ri, and the detection accuracy can be reliably improved, and the noise of the position signals S1 to S4 can be reduced. On the other hand, the reliability of the detection operation can be improved.

Further, 16 detection regions Ri are provided within an angle of 16θ (180 °) over a half rotation of the crankshaft 2, and position signals S1 to S1 corresponding to the presence or absence of the projections 7 to 10 are provided.
Since the combination of the output levels of S4 is different for each of the detection areas Ri, the rotational position of the crankshaft 2 can be detected for each angle θ (11.25 °) almost in the same manner as in the prior art. Fuel injection control and ignition control using C can be stably performed.

By simply providing the four rotation detectors 13 to 16 in the signal output device 11, which are smaller than the number of detected regions Ri, the 16 detected regions Ri can be clearly discriminated from each other, and the crank angle sensor 5 can be simplified and the number of parts can be reduced.

Also, by using the rotating drum 6,
The crank angle sensor 5 can be compactly formed in the radial direction of the crankshaft 2, and the size in the radial direction can be reduced.

On the other hand, the cylinder discrimination sensor 17 similarly has a cylinder detection signal Sa corresponding to the presence or absence of the arc-shaped projections 19 and 20.
, Sb output level combinations of four cylinder discrimination areas K1
.About.K4, the cylinder discrimination sensor 17 can be simplified and the number of parts can be reduced.

Next, FIG. 8 shows a second embodiment according to the present invention. In this embodiment, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be described. It shall be omitted. However, a feature of the engine rotational position detecting device according to the present embodiment is that a rotary plate 32 for the crank angle sensor 31 is provided on the camshaft 3 of the engine.

Here, the rotating plate 32 is made of a magnetic material such as electromagnetic stainless steel, and rotates together with the cam shaft 3 in the direction of arrow B. The first, second, third, and fourth projections 33, 3 are provided on the surface of the rotating plate 32.
4, 35, 36, and arc-shaped projections 3 for cylinder discrimination described later.
7 are formed. And these projections 33-
The circular projection 36 and the arc-shaped projection 37 are separated from each other in the radial direction of the rotating plate 32 and extend in an arc shape in the rotating direction, and axially project from the rotating plate 32 with a certain protrusion dimension.

Here, when the fourth protrusion 36 is configured to extend in the circumferential direction of the rotating plate 32 over a range of an angle θ ′ (for example, 11.25 °), the first protrusion 33 is 32 are provided at intervals of an angle 8θ ′ (90 °) in the rotation direction of 32, and these extend in the rotation direction over the range of the angle 8θ ′. Also, the second protrusion 34
Are provided at intervals of an angle 4θ ′ (45 °) in the rotation direction, and these extend in the rotation direction over the range of the angle 4θ ′.

Further, eight third protrusions 35 are provided at intervals of an angle 2θ ′ (25.5 °) in the rotational direction.
These extend over the range of the angle 2θ ′, and
Projections 36 are spaced at an angle θ ′ in the rotational direction.
And these extend over the range of the angle θ ′.

As a result, the rotation plate 32 has an angle 16θ ′ (1
80 °), the 16 detected regions R to be detected portions
i ′ (i = 1, 2, 3,..., 16) are provided for each angle θ ′, and the projections 33 to 36 are arranged in different combinations in each of the detected regions Ri ′. The rotating drum 6
Similarly, at the angle 16θ ′ (180 °) which is the other half circumference, 16 detection regions Ri ′ are formed by the projections 33 to 36.

The arc-shaped projection 37 is formed on the first projection 36.
And extends in a semicircular shape over a range of an angle of 16θ ′ corresponding to the one half circumference of the rotating plate 32, and constitutes a part of the cylinder discriminating means.

Further, a signal output device having substantially the same configuration as the signal output device 11 according to the first embodiment is provided near the rotating plate 32. The signal output device has protrusions 33 and 34. , 35, 36 are detected, and position signals S1 ', S2', S3 ', S4' are output.
The rotation detection unit and one rotation detection unit (both not shown) for detecting the presence or absence of the arc-shaped protrusion 37 and outputting the cylinder detection signal Sa ′ are separated in the radial direction of the rotation plate 32. It is provided.

On the other hand, the cylinder discriminating sensor (not shown) according to the present embodiment is configured substantially in the same manner as the cylinder discriminating sensor 17 according to the first embodiment, but the rotating plate thereof is used in the first embodiment. In this embodiment, the arc-shaped projections 19 are omitted from the rotating plate 18 (see FIG. 3) according to the above embodiment, and only the respective arc-shaped projections 20 are formed. The cylinder discriminating sensor responds to the presence or absence of the arc-shaped projection by the cylinder detection signal S.
b 'is output.

The control unit detects the absolute position of the crankshaft 2 using the position signals S1 'to S4' from the crank angle sensor 31,
The cylinder discrimination of the four-cylinder engine is performed using the cylinder detection signal Sa 'by the 1 (arc-shaped projection 37) and the cylinder detection signal Sb' by the cylinder discrimination sensor.

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. In particular, in the present embodiment, by using the rotating plate 32, the crank angle sensor 3
1 can be formed compactly in the axial direction of the crankshaft 2, and its axial dimension can be reduced in size.

Further, by providing the circular plate-shaped projection 37 for cylinder discrimination on the rotating plate 32, the cylinder discrimination sensor may be configured to output only a single cylinder detection signal Sb '. Can be simplified.

Further, since the circular plate-like projection 37 is provided on the rotating plate 32 so as to extend on one half circumference side, the 16 detection regions Ri 'located on one half circumference side and the other half circumference side are provided. The 16 detected regions Ri 'located can be identified by the arc-shaped projections 37.

Thus, for example, when the absolute position of the crankshaft 2 is detected by using the position signals S1 'to S4' and the cylinder detection signal Sa ', the rotational position of the crankshaft 2 is changed to the angle 32.theta.' Detection can be performed over a wide range (one rotation), and the detection performance of the crank angle sensor 31 can be improved.

In each of the above embodiments, the angles 16θ, 16
θ ′ (180 °) with respect to 16 detected regions Ri, R
i ′, and the minimum detection angle of the crankshaft 2 is set to, for example, 1
Although the angle θ and θ ′ are set to 1.25 °, the present invention is not limited to this, and the minimum detection angle of the crankshaft 2 is set to an angle different from the angles θ and θ ′ as necessary. Alternatively, the number of detected areas Ri and Ri 'may be increased or decreased accordingly.

In each of the above-described embodiments, the rotary plate 18 and the like are used as the cylinder discriminating sensor 17. However, the present invention is not limited to this, and the cylinder similar to the rotary drum 6 may be used instead of the rotary plate 18 and the like. A body or a cylindrical body may be provided on the camshaft 3 of the engine, and a plurality of protrusions may be provided on the outer peripheral side of the camshaft 3 which are spaced apart in the axial direction and extend in the rotational direction.

Further, in each of the above embodiments, the rotary drum 6 and the rotary plate 32 are provided on the crankshaft 2 of the engine, and the rotary plate 18 and the like are provided on the camshaft 2. However, the present invention is not limited to this. For example, the rotating drum 6, the rotating plate 32, the rotating plate 18 and the like may be mechanically connected to the crankshaft 2 and provided on another rotating shaft different from the crankshaft 2 and the camshaft 3.

In each of the above embodiments, the rotating drum 6 is provided with the projections 7 to 10, and the rotating plate 18 is provided with the arc-shaped projections 1.
9 and 20, and the projections 3
However, the present invention is not limited thereto, and a configuration may be adopted in which a rotating body, a concave portion extending in the rotational direction with respect to the rotating plate, a slit, or the like is provided. An optical sensor having a photodiode or the like may be used to detect the presence or absence of the slit.

Further, in each of the above embodiments, the case where the rotational position detecting device of the engine is applied to a four-cylinder engine has been described as an example. However, the present invention is not limited to this, and the present invention is not limited to this. You may apply to the engine of.

[0079]

As described in detail above, according to the first aspect of the present invention, a plurality of detected areas are provided extending in the rotation direction on the rotating body. Even when the shaft is at an arbitrary stop position, the absolute position of the output shaft can be detected before the output shaft rotates when the power is turned on to the signal output means, and fuel injection control and ignition control at the time of engine start can be performed early. The engine can be started and the startability of the engine can be reliably improved. Further, the absolute position of the output shaft can always be accurately detected using only the position signal from the signal output means, and the detection accuracy can be reliably improved, and the reliability of the detection operation for noise and the like can be improved. Furthermore, by outputting position signals having different combinations for each of the detection regions of the rotating body,
It is possible to reliably identify each detected area only by providing a smaller number of rotation detectors in the signal output device than the detected area, and to simplify the entire apparatus and reduce the number of components.

According to the second aspect of the present invention, a plurality of projections are provided on the rotary drum so as to extend in the rotation direction, and each of the detection areas is constituted by each of the projections. Can be clearly discriminated from each other by the presence or absence of each projection even if the target position is at an arbitrary stop position, and the absolute position of the output shaft can be reliably detected. Further, by using the rotating drum, the entire apparatus can be formed compact in the radial direction of the output shaft, and the size in the radial direction can be reduced.

Further, according to the third aspect of the present invention, a plurality of projections are provided on the rotary plate so as to extend in the rotation direction, and each of the detected areas is constituted by each of the projections. Can be clearly discriminated from each other by the presence or absence of each projection even if the position is at an arbitrary stop position, and the absolute position of the output shaft can be reliably detected. Further, by using the rotating plate, the entire device can be reduced in size in the axial direction of the output shaft.

On the other hand, according to the invention of claim 4, a plurality of detected areas are provided extending in the rotational direction on the rotating body provided on the crankshaft side of the engine, and the cylinder discriminating means provided on the camshaft side of the engine. Is configured to output a different cylinder detection signal for each cylinder, so that when the engine is started, the absolute position of the output shaft can be detected when power is supplied to the signal output means. It can be performed. Thus, fuel injection control, ignition control, and the like at the time of starting the engine can be started at an early stage, and the startability of the engine can be reliably improved. In addition, the absolute position of the output shaft can always be detected accurately,
The reliability can be improved, the entire apparatus can be simplified, and the number of parts can be reduced.

According to the fifth aspect of the present invention, a plurality of detected areas are provided on the rotary plate of the cylinder discriminating means so as to extend in the rotation direction. Even when the cylinder is at an arbitrary stop position, the cylinder of the engine can be determined when the power is turned on to the cylinder signal output means, and the startability thereof can be reliably improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an engine rotational position detecting device according to a first embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing a crank angle sensor in FIG. 1;

FIG. 3 is an enlarged front view showing a rotary plate of the cylinder discrimination sensor in FIG. 1;

FIG. 4 is an enlarged sectional view showing a signal output device of the crank angle sensor.

FIG. 5 is an enlarged sectional view showing a cylinder signal output device of a cylinder discrimination sensor.

FIG. 6 is a characteristic diagram illustrating a relationship between a position signal output from each rotation detection unit of a crank angle sensor and a detection angle for a crankshaft.

FIG. 7 is a characteristic diagram illustrating a relationship between a crank angle and an output state of a cylinder detection signal, a detection angle, an injection signal, and a start signal when the engine is started.

FIG. 8 is a front view showing a rotation plate of a crank angle sensor used in the engine rotation position detection device according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine main body 1A cylinder 2 Crankshaft 3 Camshaft 5, 31 Crank angle sensor 6 Rotating drum (rotating body) 7-10, 33-36 Projection part 11 Signal output device (Signal output means) 13-16, 23, 24 rotation Detecting section 17 Cylinder discriminating sensor (cylinder discriminating means) 18 Rotating plate 21 Cylinder signal output device (cylinder signal outputting means) 32 Rotating plate (rotating body) Ri, Ri 'Detected area (detected section) K1 to K4 Cylinder discriminating area (Detected area) S1 to S4, S1 'to S4' Position signal Sa, Sb, Sa ', Sb' Cylinder detection signal

Claims (5)

[Claims] 1. A rotating body which is rotated by an output shaft of an engine and provided with a plurality of detected parts, and a signal which is provided near the rotating body and outputs a position signal corresponding to each detected part of the rotating body. In the rotational position detecting device for an engine, comprising: an output unit, each of the detected portions of the rotating body is formed on the rotating body with a shape different from each other at predetermined predetermined angles,
A plurality of detected areas extending along the rotation direction of the rotator, wherein the signal output means has a plurality of rotation detecting sections and has a position signal having a different combination for each of the detected areas. A rotational position detection device for an engine. 2. The rotating body includes a rotating drum provided on an output shaft of an engine, and each of the detected areas projects radially from an outer peripheral side of the rotating drum while being spaced apart in an axial direction of the rotating drum. A plurality of protrusions extending in the rotation direction of the rotary drum over a range related to the angle,
Each rotation detecting section of the signal output means has a corresponding one of the projections.
2. The engine rotational position detecting device according to claim 1, wherein the rotational position detecting device is configured to be spaced apart in the axial direction of the rotating drum to detect the absence. 3. The rotating body comprises a rotating plate provided on an output shaft of an engine, and each of the detected areas is provided on a surface of the rotating plate at a distance in a radial direction of the rotating plate. A plurality of projections extending in an arc shape over a range related to the angle, wherein each rotation detection unit of the signal output means detects the presence or absence of each of the projections in a radial direction of the rotary plate. The engine rotational position detection device according to claim 1, wherein the rotation position detection device is configured to be provided at a distance from the engine. 4. A crankshaft-side rotating body provided on a crankshaft of an engine and having a plurality of detected parts formed thereon, and a position signal provided near the rotating body and corresponding to each detected part of the rotating body. In the engine rotational position detecting device, comprising: a signal output unit that outputs a signal; and a cylinder discriminating unit that discriminates the cylinder of the engine. The detected portions of the rotating body are different from each other at predetermined predetermined angles. Formed on the rotating body with a shape,
A plurality of detected areas extending along the rotation direction of the rotator, wherein the signal output means has a plurality of rotation detecting sections and has a position signal having a different combination for each of the detected areas. Further, the cylinder discriminating means is provided at least on the camshaft side of the engine and outputs a different cylinder detection signal for each cylinder of the engine. Detection device. 5. The cylinder discriminating means includes a cam plate-side rotating plate that rotates integrally with the cam shaft, and a rotating plate having a number corresponding to the number of cylinders of the engine, the rotating plates having different shapes. A plurality of detection areas extending in the direction of rotation of the rotating plate, and cylinder signal output means having a plurality of rotation detection units and outputting differently detected cylinder detection signals for each of the detection areas. The engine rotational position detecting device according to claim 4.