JP2664147B2 - Throttle valve angle detection device and throttle valve angle detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]   The present invention relates to an angle detection device and method, and particularly to an internal combustion engine
Throttle valve angle detection device suitable for detecting the angle of the throttle valve
It relates to an angle detection method. [Conventional technology]   Angle detection method that outputs the rotation angle as an absolute value signal
The method and apparatus are known from JP-A-58-47212.
You.   According to the angle detection method and device shown in this conventional example,
For example, shift the pattern of multiple channels slightly in the rotation direction.
And the combination of the patterns of each channel is
The angle is set to a specific two-signal coded signal so as to correspond to the angle.
It is configured to perform detection. In addition, fine signals are required.
When necessary, switch to the incremental type detector
It is configured to detect a small angle. [Problems to be solved by the invention]   According to the prior art configured in this manner, the channel
For example, if the number is 5, 2^Five= Combination of 32 patterns
Angle measurement range (360 degrees in this conventional case)
Is divided into 32 sections, the first section is (360/32) degrees, the second section
The section is (360/32) degrees x 2 and the third section is (360/32) degrees x 3
... The n-th section is (360/31) degrees × n (where n = 1 to 32
Number) for each of the 32 binary codes
Angle can be assigned, and the angle is set to 32 absolute values.
Can be detected.   However, with this configuration, the absolute value signal for each
You need to get 360 pattern combinations
Yes, with at least 10 channels
Therefore, there is a problem that the sensor becomes large.   In addition, increment type detection with juxtaposed minute angle signals
When switching to the instrument to obtain a signal, the absolute value signal cannot be obtained
There is a problem.   An object of the present invention is to provide a highly accurate angle even in a specific area.
Throttle valve angle detection device and throttle valve angle detection
It is to provide an exit method. [Means for solving the problem]   The above object is intended for a specific rotation angle of a throttle valve of an internal combustion engine.
And generates a corresponding absolute value signal.
The absolute value signal is generated more densely in the low opening region than in the high opening region.
Generating means, and a predetermined interval according to the rotation of the throttle valve.
Means for generating an increment signal;
By interpolating the signal with the increment signal,
Means for determining the rotation angle of the throttle valve.
Is achieved.   Further, the above object is to provide a specific rotation angle of a throttle valve of an internal combustion engine.
High opening area in the low opening area of the throttle valve
Absolute value signal is generated more densely than the
Generate an increment signal at a predetermined interval in accordance with
The absolute value signal is interpolated by the increment signal, and the interpolation is performed.
The rotation angle of the throttle valve is determined by the increment signal.
Achieved by seeking degrees. [Action]   The present invention configured in this manner is used for the adjacent absolute baths.
The increment signal generated during the
Since it is used as an interpolation signal between
Improves measurement accuracy without increasing the number of elements that generate UUT signals
can do.   In particular, weight each absolute signal, and
Addition / subtraction of the increment signal to the attached signal
By processing, the measurement angle can be read directly with high accuracy.
You.   For example, as in the conventional example, the absolute
Reute type detector generates 30 binary coded numbers
, The next binary coded signal from the initial position
The section up to the occurrence of the signal is (360/30) degrees = 12 degrees
The value divided by the number of increment signals as one unit
As an interpolation signal to the absolute signal indicating the shear position
Granted. Increment signal spans the entire measurement range
To generate 360 signals at equal intervals
For example, the number of interpolation signals between each binary coded signal is 360/30.
You. Therefore, the next binary coded signal is generated from the initial position.
12 interpolated signals during incremental generation
Occurs. When the detector stops at an angle of 10 degrees,
The output of the absolute type detector is incremented by “1”
The type detector outputs the count number “10”. These two
Combine the outputs and recognize “1” plus “10” as an angle of 10 degrees
The detection circuit is configured as follows. Similarly, if the detector is 90
When stopped at the right angle, the output of absolute type detection is
“7”, the increment type detector outputs “6”. Both sides
Combines force and recognizes "7" plus "6" as 90 degrees angle
The detection circuit is configured as described above.   Note that the increment signal is divided into smaller signals to further divide the signal.
Between signals. From this 1deg
Small angles can also be detected.   Specific weighting of the absolute signal corresponding to the actual angle
And increment the count value of the increment signal.
Is also effective. For example, the first absolute
Weight the repeat signal 12 degrees. In this 12 degrees
When the count value of the increment signal is added or subtracted, the value becomes
Is a value indicating the absolute value of the rotation angle of the detector. 〔Example〕   Hereinafter, an embodiment of the present invention will be described.   Before the description of the configuration and operation of the embodiment, detection in this embodiment
An absolute signal by means of a magnetoresistive element,
The principle of detecting the increment signal will be described.   Fig. 15 shows the resistance change of the magnetoresistive element with respect to the magnetic field.
It is a thing. FIGS. 15 (a) and (b) show magnetic fields on the same plane.
To the angle θ at which the current flowing through the magnetoresistance element and the magnetic field intersect
This shows the resistance change of the element.
Resistance R₀However, it has the characteristic that θ decreases about 2% at the position of 90 degrees.
ing. FIG. 12 (c) shows the magnetic field strength at θ = 90 degrees.
This shows the change in resistance with respect to
Initial resistance R₀Can also be reduced by about 2%
You.   The detection principle of this embodiment is applied to the magnetoresistive element as described above.
Is detected by the change in resistance generated by the magnetic field
is there.   Next, it is detected by the magnetoresistive element according to FIGS. 16, 17, and 18.
The increment signal will be described.   FIG. 16 shows the arrangement of the magnetic material and the magnetoresistive element.   A magnetic material is formed around the outer periphery of the drum 1 which rotates by receiving a rotational force.
Formed on the substrate 2 at a certain distance from the outer periphery of the drum 1
Where the magnetoresistive elements formed in
It has become.   FIG. 17 shows an increment signal magnetic body of the drum 1 and the same.
2 shows a state in which the magnetoresistive element opposed to FIG. Magnetic material
Are arranged so that the same poles face each other, and one unit is λ
The elements R1 to R8 are arranged at an interval of 1 / 4λ.   The numbers in the figure below are magnetic numbers for explanation
It shows the position of. The R-size display in FIG.
When the resistance value is maximum, that is, when no magnetic field is applied,
It shows a state where the field has been added and reduced by about 2%.   Now, the state where the element R1 is at the position will be described.
The resistance state of each element at that time is shown on the line.
Element R1 receives no magnetic field and is large, and element R3 receives the strongest magnetic field.
And the resistance is about 2% lower, R is small, and element R5 is
As with R1, R is large, and element R7 is as small as R3.
Become.   The elements R2, R4, R6, and R8 are slightly in the position where the magnetic field is received.
The resistance value is approximately in the middle between the large R and the small R.   Next, the magnetic body moves 1 / 4λ in the rotation direction, and element R1 moves to the magnetic body.
The resistance value state of each element at the position of
Is shown. Elements R1, R3, R5, R7 are state elements R2, 4, 6, 8
And the resistance value is almost in the middle between R large and R small.
Become. On the other hand, the element R2 is located at an intermediate position between the NS poles and receives a magnetic field.
The element R4 has a large R without receiving a magnetic field on the S pole.
R6 is small R as in element R2, and element R8 is large R as in element R4.
State.   After that, when the element R1 faces the position
The resistance value of the child repeats the same state with a period λ.   Therefore, the angle corresponding to one unit λ of the magnetic body is set to the resistance of each element.
It can be detected as anti-change.   The resistance change of each element described above shows each element in FIG.
It is taken out as a voltage change in such a bridge configuration. Element R
The signal from the bridge consisting of 1, R3, R5, R7 is A phase,
The signal from the bridge consisting of R2, R4, R6, and R8 is referred to as B-phase.
You.   FIG. 20 shows the voltage change in each bridge. In the figure
Numerals indicate the same positions as in FIGS. A
Phase e_A1The terminal voltage is e due to the resistance change of elements R1 and R3._A2end
The child voltage is generated by the resistance change of the elements R5 and R7, and the A-phase signal is e.
_A1−e_A2Take it out in the form of a signal. Similarly for the B-phase signal
Also e_B1−e_B2Take it out in the form of a signal.   Therefore, the phases A and B have the same period as the magnetic recording pitch λ.
That is, the signal is shifted in phase by 1 / 4λ.
Rotation angle corresponding to the peripheral phase λ of the phase is detected by the magnetoresistive element
Is the minimum resolution angle signal. Dora need two phases
This is for determining the rotation direction of the system 1 and will be described later.   The rotation angle θ corresponding to the magnetic recording pitch λ_minIs Dora
When the diameter of the program 1 is D Becomes   Next, the absolute signal will be described.   FIG. 21 shows the structure shown in FIG.⁰Magnetic body for signal and 2⁰Signal detection
FIG. 4 is a development view in which an element part is taken out. Absolute
The magnetic material for one bit is composed of two tracks.
There are only two opposing detection elements in each track.
Are arranged. The length of one magnetic material is the same as the ink
Λ same as the case of the increment signal, and the arrangement of the detecting elements is λ / 2
It has become an interval.   Figure 22 shows the resistance change of each element R01, 02, 03, 04
The element center line (the straight line connecting the elements R02 and R04 and the elements R01 and R03
(The middle position of the connecting straight line)
of the resistance value state of each element at each position of z
The symbols are shown on the same line. R large and R small in the figure
As in Fig. 18, the resistance value with no magnetic field and receiving the magnetic field
Indicates a state of about 2% reduction.   When the element center is at the position a, the element R01 generates a magnetic field.
Since it receives a little, the state between R large and R small, element R02 is the same
Like, the elements R03 and R04 have large R because there is no magnetic field in the facing part.
Is shown.   At the position where the element center line is f, the element R01 is at the position of g.
The element R02 is located at the position of e, and is not subjected to a magnetic field.
R small due to magnetic field, elements R03, R04 are still magnetic materials
Because there is no, it is in the state of R size. Next, the element center line
When moved to the position of g, the element R01 is
The element R03 starts to face the magnetic material
, A state intermediate between R large and R small. Elements R02 and R04 are
The resistance value of element R02 is between R large and R small.
During this time, the element R04 is large. The element center line moves to h, i, j
Then, element R01 is large, large, large, element R02 is large, large, large, large.
Element R03 is R small, R middle, R large, Element R04 is R large, R middle, R small
Changes. Here, the elements R01 and R03 are at the position of f,
For the elements R02 and R04, the pattern of resistance change from the position of h
Each transitions to a different state.   When the magnetic material further moves, the elements R01 and R03 at the V position have x
The pattern of resistance change of elements R02, R04 changes at the position
The same resistance as the change pattern before the f position and before the h position
Make a change.   Each element R01, R02, R03, having a resistance change as described above
R04 has a bridge structure shown in FIG. This bridge
E in₀₁, E₀₂Figure 24 shows the change in terminal voltage.
A to z in the figure correspond to the positions in FIG.
You.   e₀₁Terminal voltage corresponds to resistance change of elements R01 and R03
For example, at the position e, the element R01 is intermediate between the large R and the small R, and the element R01 is
03 is slightly larger than V / 2 because R is large.
In the f position, both elements R01 and R03 have the same resistance and V / 2, and the g position
In this case, element R01 is between R large and element R03 is between R large and R small
Therefore, the voltage becomes higher than V / 2. Where e₀₁Terminal voltage is f
From V / 2 or lower to V / 2 or higher
You. While e₀₂At the terminal, from the voltage of V / 2 or more at the h position
Invert to V / 2 or less.   And e₀₁V position at terminal, e₀₂At the terminal, at the X position
The voltage state reverses and e₀₁, E₀₂The terminal has the same voltage
g and W.   Therefore e₀₁−e₀₂At the g position as shown in FIG.
Invert from-to + and from + to-at W position. This g
And W are the changing points Z of the two magnetic tracks.₀₁, Z₀₂To
Corresponding.   Also, as shown in FIG.¹, 2^Two, 2^ThreeAbsolute of Bit
Signal is formed similarly. So look at each bit status
In this way, absolute position detection is performed.
A 16-bit absolute signal is formed in the bit configuration.
be able to.   As described above, the change point of the absolute signal is one bit.
Change in magnetic material arrangement of two magnetic tracks forming a tut
Point (Fig. 24 Z₀₁And Z₀₂).   In addition, the same is true in the two tracks forming one bit.
In one position, magnetic material is always placed on only one track.
The unit λ on the track against the elements R04, R03
Only one bit of the absolute signal in the continuous section
Signal on the track opposing elements R02 and R01
No signal is generated in the section where the body is located.   In FIG. 24, 4λ, that is, four A-phase or B-phase signals
Caused a one-step change in absolute, but Z₀₁And Z
₀₂Absolute by changing the number of magnetic substances contained between
It is possible to arbitrarily set a change point corresponding to one stage of Ute
it can.   Next, an embodiment of the present invention is applied to detection of a throttle valve opening of an internal combustion engine.
An example applied to the throttle sensor used will be described.
You. FIG. 11 shows a longitudinal sectional view of the throttle sensor 20.
Fig. 12 shows the state of attachment to the engine. The magnetic material of the drum 1a
The outer periphery of the drum 1a is magnetized.
Shaft integrated with the lever 3 which contacts the valve shaft 23
And is fixed to the screw 4 by a screw 5. In the direction that the throttle valve 24 opens
Exerts a force on the lever 3 from the throttle valve shaft 23, and the shaft 4
To transmit rotational force. On the other hand, when the
-3 is released, but the return spring 11 is always closed.
It is loaded and returns by the elastic force of the return spring 11.   The board 2a is supported by a stand 7 attached to the base 6.
The signal from the board 2a is circuited by the cable 8
9 and performs signal processing and is externally connected by the lead wire 10.
It is configured to be taken out.   The throttle sensor 20 is a throttle that penetrates through the intake cylinder 22.
It is attached to one end of the valve shaft 23. This throttle valve shaft 23 has a throttle
The valve 24 is fixed and the driver's instruction is transmitted to the hook 27.
Thus, the throttle valve 24 is opened and closed. The opening of the throttle valve 24 is
This signal is detected by the
Input signal of the control unit 25. Control
The unit 25 also has a rotation speed signal, the engine 21
A signal such as a water temperature and an air-fuel ratio that knows the state of the air conditioner is input.   In the control unit 25, from the throttle sensor 20
Engine 21 based on the opening signal and rotation speed of the throttle valve 24
Calculate the amount of intake air per revolution and calculate the amount of intake air
The amount of fuel to obtain the specified air-fuel ratio
Calculate as the valve opening time. And only for valve opening time
Output a signal to the
At times, it controls the ignition signal and the like.   FIG. 2 shows a magnetic body and a substrate around the drum 1a shown in FIG.
It is a development view of the magnetoresistive element on 2a.   On the outer periphery of the drum 1a, a high-resolution signal and rotation direction
And 2 corresponding to the increment signal for
Four bits of magnetic material forming one bit by the track
And the substrate 2a corresponds to each track.
R1 'to R8', R01 'to R04', R11 'to R1
4 ', R21' ~ R24 ', R31' ~ R34 'have the above mentioned spacing
It is arranged.   Next, the configuration of the absolute signal in this embodiment will be described.
Will be described. FIG. 13 shows the relationship between the opening degree of the throttle valve 24 of the internal combustion engine.
1 cycle of intake air with pulse width for calculating injection amount
Fuel supply solenoid valve 26 to obtain a predetermined air-fuel ratio
The amount of fuel supplied per time, corresponding to the time to open
Is equivalent to If the throttle valve opening in Fig. 13 is 90
When the interval is detected by a 4-bit absolute signal, one data
The opening angle per hit is 5.625deg, and the pulse width change is very low.
In the opening range, the engine condition changes suddenly with one data change
You can see that. Checking the opening of throttle valve 24 with such characteristics
The higher the degree of opening, the higher the accuracy required. For this
Needs to know the absolute opening with high accuracy in the low opening range.
You.   This embodiment has a 4-bit configuration, and a 4-bit absolute
The 16-step signal represented by the
And the pulse width changes slowly with respect to the throttle valve 24 opening.
High pitch arrangement in a high opening area
It is configured to generate equally spaced signals. Such an
As shown in Fig. 14,
The pulse width change at the point of change of the absolute signal
The relationship can be a straight line, and one of the absolute signals
The accuracy represented by the condition can be made almost equal in all measurement sections
it can.   Next, the change point of the absolute signal shown in FIG.
The relationship between the opening of the valve 24 and the number of increment signals
It is shown in FIG. In this embodiment, each of the absolute signals
Change the value assigned to the change point from the origin position to each change point.
It consists of a cumulative number of high-resolution signals representing the angle at
You. 14 steps of up to 30 degree opening with a sharp pulse width change
Causes a change in pulse width and a gradual change in pulse width 30
The section between degrees and 90 degrees is represented in two stages. What
The signal structure in the figure is gray code, but other codes
For example, a binary code may be used.   The change point of the absolute signal and the increment signal
The relationship will be described with reference to FIG. In this embodiment
Is the absolute signal corresponding to the 30 degree opening of the throttle valve 24.
In the section up to change point 14, the Nth absolute signal
The cumulative number of increment signals included up to the change point of And change point 15 to the number of increment signals
With 200, the last change point 16 is made to correspond with 315. This
The increment signal of
What happens. The increment signal is about 90 degrees
It is composed of an A phase and a B phase having a phase difference.   For example, as shown in FIG.
At the point of change point 6 of
The configuration includes 21 signals, and the absolute signal 6 is detected.
You can know the absolute angle position when
You. In addition, the corresponding input at the change point of the absolute signal
The number of increment signals is set in the counter, and the next transition point is generated.
Up to counter (corner) with increment signal until raw
Degree), down (angle decrease)
Knowing the detailed current position while the Ute signal changes
Can be. In other words, the absolute position detection
Interpolation detection can be performed with a resolution equivalent to the resolution of.
Also, the increment signal is divided by k times (k is an integer)
The same applies to the signal configuration. Absolute in this case
The signal change of
The number of bits of the Ute signal can be reduced.   Next, referring to FIG. 4 (a), the absolute signal is detected.
Outline of absolute position calibration and signal processing circuit configuration
I do.   Absolute detected by the magnetoresistive element on the substrate 2a
The beat signal is waveform-shaped by the waveform shaping means WF.
Transformer GBC for conversion from gray code to binder
Converted to recode. This signal is the latch circuit RC and the number
Absolute signal previously stored in value comparator CC
If there is a difference in the absolute signal,
Counters the contents of memory MC with signals from the imaging circuit TC
Reset to NC. At this time, the absolute signal decreases
When moving in the direction, after the change as described above (current value)
1 is added to the absolute signal of
In this case, the absolute
Creates a signal that specifies the address by adding 1 to the
You. Data from memory MC is absolute
It consists of the number of resolution signals representing each change point of the
You. After setting the calibration value in the counter,
Solitate signal stored in latch RC as comparison data
Then, a series of calibration operations is completed.   In addition, increment until the next absolute signal change.
Counter with a high-resolution signal generated from the
Drive the NC, the value in the counter NC is always the current absolute position
Is represented.   Next, the signal processing detected by the magnetoresistive element on the substrate 2a is performed.
Details will be described.   The bridge of the magnetoresistive element formed on the substrate 2a is the second
It is constructed as shown in Fig. 3 and the A phase is e_A′, B phase is e_B´, 2⁰Bit
e₀´, 2¹Bit is e₁´, 2^TwoBit is e_Two´, 2^ThreeBit
e_Three′ And performs signal processing.   As shown in FIG. 4 (b), a power supply terminal is connected to the magnetoresistive element.
Apply voltage from 100. Output e_A′, E_B′, E₀′
~ E_ThreeIs input to the comparators 101a to 101f, respectively. Yellowtail
There is no problem if the four element resistances in the azalea are the same.
Actually, there is variation, and this variation causes
Offset adjustment circuit to cancel the generated potential difference
Paths 102a-102f are connected to one of the inputs. Offices
The operation of the gate adjustment circuits 102a to 102f will be described using 102a as an example.
Is to adjust the potential at point a shown in FIG. In this embodiment,
A waveform shaping circuit composed of hybrid ICs.
In such a case, R_aAnd R
_bAre provided by laser trimming.
And the potential at point a is adjusted.   109 is an exclusive OR (hereinafter referred to as EX-OR) gate, 110
a to 110d (for example, standard theory such as HD74LS86 manufactured by Hitachi, Ltd.)
Conversion from gray code to binary code
Path 111 is the current absolute signal by the latch signal 200.
No. 105 'to 108' (for example, CD404 manufactured by RCA)
Standard logic IC such as 2B), 112 is the current absolute
Signals 105 'to 108' and absolute signal 1 in the latch 111
Comparator for comparing 05 "to 108" (for example, RCA CD4585B)
, And 113 are output from the comparator 112 (105 'to 1).
08 ') <(105 "to 108"), the output that occurs
Add signal 201 to current absolute signal 105'-108 '
To return to the absolute signal before reduction and output
Adder (standard logic such as GH14008B manufactured by Hitachi, Ltd.)
IC), 114 is memory (for example, HN48276G manufactured by Hitachi, Ltd.)
Absolute from adder 113 with standard IC memory
The calibration value of the absolute position corresponding to the signal is output. 115a, 115
b and 115c are data from the memory 114 by the preset signal 203.
Preset counter (for example, RC
Standard logic IC such as CD4029B manufactured by Company A), 117 inputs signal 202
Set data to preset counters 115a, 115b, 115c
Generate preset signal 203 and latch signal 200
Inverter as shown in Fig. 5
118a, 118b (for example, a standard such as Hitachi's HD74LS04
Logic IC), D-flip flops 121a and 121b (for example,
Standard logic ICs such as HD74LS74A manufactured by Hitachi, Ltd.)
119,120 (for example, HD74LS11, HD74LS08 made by Hitachi, Ltd.
Such as standard logic IC). 170 is the resistance r₁,
r_Two, Capacitors C1 and C2, and EX-OR gate 110S
This is an initial setting circuit to perform.   122 is a clock oscillation circuit, and 123 is a rotation
The increment signal multiplication circuit (represented by DJC in FIG. 4a)
ing. ), 599 are preset counters 115a, 115b, 115c
Output that converts the state of outputs 501-512 to a duty signal.
Power processing circuit.   Next, the initial setting will be described as the operation of the signal processing circuit.
I do. The power supply to the signal processing circuit of FIG.
Supplied from control unit 25 that controls 21
It is. As shown in FIG. 5, the ignition key 700 is
When it is entered, the battery 80 first goes to the control unit 25.
Power is supplied from 0, and then the controller is
Power supply line from the roll unit 25 to the slot sensor 20
A predetermined power is supplied at the input 10a. Initial setting circuit 170
Resistance r₁And r_TwoAre equal and the capacitance of the capacitor is C₁<C_TwoTonatsu
Initial setting circuit 170 V_C1, V_C2Fig. 7
As shown in (a) and (b), the same potential V_1nUntil you reach
, A time difference of ΔT occurs. Therefore V_C1, V_C2And enter
The output of the EX-OR gate 110S is as shown in FIG.
The output is delayed by T delay from the power supply for ΔT time
is there. This T delay is supplied to the signal processing circuit 9 in FIG.
From when the power is supplied to when each processing circuit is in operation
Is set to   7 (c) is the OR gate 2 of the timing circuit 117.
Input to 99 (for example, standard logic IC like RCA CD4071B)
Is done. The output 300 of the OR gate 299 is unconditionally only during ΔT
It becomes H state. Operation of Timing Circuit 117 Sixth
This will be described in conjunction with the time chart shown in the figure. OR gate 29
The output 300 of 9 is the data input terminal of the D-flip-flop 121a.
Entered in child.   The clock signal 204 from the clock oscillator 122 is D-free.
When changing from L to H at the clock terminal of the flip-flop 121a
At this time, the signal 302 becomes H state, and at the same time, the AND gate 11
Data input terminal for 9,120 and D-flip flop 121b
Is input to At this time, the D-flip flop 121b
The signal 304 from the inverting output terminal is H, and the AND gate 12
The output 203 of 0 changes from L to H. This signal 203 is
Data capture and setting of the counters 115a, 115b and 115c
Signal and the calibration value from memory 114 is
Set to the counters 115a, 115b, and 115c.   In the initial setting state, the throttle valve 24 is set to the absolute position shown in FIG.
If the signal falls between the transition points 5 and 6,
Are detected by the magnetoresistive elements on the substrate 2a and are detected by the comparators 101a to 101a.
The waveform is shaped by 101d and the absolute signal is 105-108
Is detected with a 0111 gray code. This signal
0101 by gray code → binary code conversion circuit 109
And 105 'to 108' are in this state. This 101
The absolute signal is directly input to the adder 113.
You. The adder 113 adds 0101 and the state of the signal 201 and sums the result.
The result is output to the memory 114. Signal 201 is the current absolute
Signals 105'-108 'and signals 105 "-105 in the latch 111.
Compare with 8 "and output status when 105'-108 '<105" -108 "
Therefore, the initial state is L.   The adder 113 performs an operation of 0101 + 0, and stores 0101 in the memory 114.
Output to The memory 114 receives 0101 as an address.
Change point of absolute signal in the sampling address 0101
The calibration value corresponding to 5 is in the output state.   Accordingly, the preset signal 203 from the timing circuit 117
To the preset counter 115a, 115b, 115c
Calibration value (for example, in decimal number)
60) (The number of calibrations will be described in detail later.)
). In the timing circuit 117, the inverter 118b
When the inverted signal 301 changes from L to H, D-flip-off occurs.
The output of the drop 121b becomes H and is input to the AND gate 119.
You.   In the AND gate 119, the signals 302 and 303 become H, and the clock
At the rise of the signal 204, the latch signal 200 is set to H. This rat
When the latch signal 200 becomes H, the data of 105 'to 108'
The initial setting of the absolute position calibration is completed.
You.   Next, the operation of the signal processing circuit after the initial setting will be described.
You. At the time of initial setting, change points 5 and 6 of the absolute signal
And then the throttle valve 24 moves in the opening direction to
Trigger signal transition point 6 is assumed.   This state is detected by the magnetoresistive element on the substrate 2a.
The state of 8 becomes 0101.   This signal is converted by the gray code → banal code conversion circuit.
Is converted to 0110 (Banari code) and 105'-108 '
State. In the comparator 112, the signals of 105 'to 108'
State of previously stored signals 105 "-108" in switch 111
Compare with At this time, 105 'to 108' (0110)> 105 "to 1
08 ″ (0101), 201 remains L and 01 in the adder 113
An operation of 10 + 0 is performed, and 0110 is output to the memory 114. Me
The memory 114 receives 0110 as the address, and the address 0
Calibration corresponding to the change point 6 of the absolute signal in 110
Output value (for example, 84 in decimal)
Will be described in detail later).   On the other hand, 105 'to 108'108105 "to 108"
The output 202 from the comparator 112 is in the L state. This signal
Inverted by the inverter 118a of the timing circuit 117 and OR gate
Is entered in the port 299. The output of OR gate 299 is D-
The data is input to the data input terminal of the flip-flop 121a.
Thereafter, the operation of the timing circuit 117 is the same as that at the time of the initial setting.
Yes, presets to preset counters 115a, 115b, 115c
The calibration signal from the memory 114.
New data on the latch 111 after the preset
The latch signal 200 stored in 5 'to 108' is output. Latch 111
At the same time, the comparator 112 captures new data at 105 '~ 10
8 ′ = 105 ″ to 108 ″ is detected and the output signal 202 is set to H. Obedience
The output 300 of the OR gate 229 of the timing circuit 117 is L
The D-flip-flops 121a and 121b receive the clock signal 20.
The outputs 302 and 303 are set to the L state by the input of 4,301.   With the above operation, setting of calibration values and latching of new data
Completes and detects the next absolute signal change
It has become.   Next, the throttle valve rotates in the closing direction and the absolute signal changes.
A description will be given of the absolute position calibration when the number of conversion points decreases.
From the state between the change points 6 and 7 of the absolute signal
If it decreases between change points 5 and 6, the data of 105'-108 '
Is 0101 and the comparator 112 is 0101 of 105'-108 '
0110 stored in the switch 111 is compared with 105′-108 ′ <1
The signal 201 becomes H level due to the result of 05 ″ to 108 ″.
Thus, an addition signal 1 is generated. In the adder 113, the current data 010
Perform 1 + 0001 operation, output 0110 and input to memory 114
You. In memory, data at address 0110 (binary)
That is, the data of the change point of the sixth absolute signal
(84 in decimal) and outputs the timing circuit 117
Of the preset counters 115a, 115b, 11
Set to 5c to perform absolute position calibration. This is the opening
Is moving in the closing direction.
To the counters 115a, 115b, and 115c.
The value to be calibrated is in the interval 5 of the absolute signal.
The maximum count number existing between 6, that is, Absolute
Calibration with the count number corresponding to the change point 6 of the
It is necessary. Therefore, the absolute value at the change point of the absolute signal is
Position calibration is performed at the changing point in both the opening and closing directions of the throttle valve 24.
It is designed to perform accurate absolute position calibration.
Can be.   Next, based on FIGS. 8A and 8B, the A and B phase signals 1
03,104 will be described.   From the A-phase input terminal 801 to the input terminal 80 of the shift register 803
3a and connect to one input of EX-OR gate 818,
From input terminal 802, input terminals 804a and 804a of shift register 804
And one input of an EX-OR gate 809. Shift
Q of 803₁One output of EX-OR gate 808 is input from output 803b.
Connected to one input of the power and EX-OR gate 808, Q_TwoOut
The force 803c is connected to one input of the EX-OR gate 812, and Q_Three
The other input of EX-OR gate 817 and EX-O from output 803d
The other input of the R gate 812 and one of the EX-OR gates 813
Connect to the input of_FourOutput 803e is the other of EX-OR gate 813
Connect to the input of. EX-OR gate 807 output 807a is EX-O
Connect to the other input of R gate 808, and connect to EX-OR gate 809
The output is one input of OR gate 811 via inverter 810
And the output 812a of the EX-OR gate 812 is connected to the EX-OR gate 8
Connect to one input of 14 and output 813a of EX-OR gate 813
Is connected to one input of OR gate 815. Also shift
Each Q of Vista 804₁, Q_Two, Q_Three, Q_FourOutput 804b, 804c, 804d, 804e
In the same way to the inputs of EX-OR gates 816, 819, 820
And output of EX-OR gates 816 and 817
Connection as shown, and the output 818a of the EX-OR gate 818 is OR gated.
Connected to the other input of the gate 811 and the output of the EX-OR gate 819
819a is connected to the other input of EX-OR gate 814, and EX-OR
Output 820a of gate 820 connects to the other input of OR gate 815
I do. The output of the OR gate 811 is the data of the D flip-flop 805.
Data input terminal 805a, and the output of EX-OR gate 814
Connect to clock input terminal 805b of D flip-flop 805
And the Q output 805c of the D flip-flop 805 is
To the up / down switching input terminal 806b of the counter 806
Connect the output of OR gate 815 to up / down counter 8
Connect to the 06 clock input terminal 806a. Clock oscillator
Output 821a of 821 is the clock input of shift registers 803 and 804
Connect to terminals 803f and 804f.   FIG. 8 (b) shows a pulse of the A-phase signal shown in FIG. 8 (a).
The rotation direction of a rotating body (not shown)
Time tick when performing a positive count after doing another
Yat. In FIG. 8 (b), 821a is a clock.
Signal, 801a is A phase signal, 802a is B phase signal, 812a is direction
Constant pulse, 813a is count pulse, 805c is direction signal
You. Clock signal 821a at output 821a of clock oscillator 821
Are numbered 211 to 229. A phase input terminal
The phase A signal 801a in FIG.
When the clock signal 821 is input to the input terminal 803a of the
Q of shift register 803 at rising edge 213 of a₁Output 803b signal
Is output, and then the pulse of the clock signal 821a is input.
Q shifted sequentially every time_TwoOutput 803c, Q_ThreeOutput 803d, Q_Four
The signal of the output 803e is output. Output 807a signal is shifted
Q of register 803₁Data 803b and Q_ThreeExclusivity of data 803d
The sum signal is the output signal of the EX-OR gate 807.
The constant pulse 812a is the Q of the shift register 803._TwoOutput 803c and Q_ThreeOut
The output signal of the EX-OR gate 812 is the exclusive OR signal of the force 803d.
And Q of the shift register 803 of the count pulse 813a.
_ThreeOutput 803d and Q_FourEX-OR gate with exclusive OR signal of output 803e
This is the output signal of port 813. The signal at output 808a is
Q of 803₁Of output 803b and output 807a of EX-OR gate 807
Exclusive OR signal which is the output signal of EX-OR gate 808
The clock signal 821a rises at the shaded areas 891 and 892.
Period of rise 213 and rise 215 and rise 225 and rise 228
The EX-OR gate 809 is opened during the period of
Check the logical value of the phase signal 802a. Direction signal 805c is D frits
Up / down with the output signal of the Q output 805c of the pop-up 805
Input to the up / down switching input terminal 806b of the counter 806.
Is forced.   Next, the circuit operation of FIG. 8A will be described with reference to FIG.
explain. The output signal 807a of the EX-OR gate 807 is
Q of 803₁Output 803b and Q_ThreeExclusive OR of output 803d
Of the rising edge 213 and rising edge 215 of the clock signal 821a.
EX-OR gate for section and sections of rising 225 and rising 228
809 is opened and the phase at the time of the rise and fall of the A-phase signal 801a is
The logical value of the hand side, that is, the B-phase signal 802a is checked. Also above
During the period, the EX-OR gate 809 becomes the B-phase signal 802a and the shift register.
Q of 803₁Between the output 803b and the output signal 808a of the EX-OR gate 808.
The exclusive OR is used and the data in the rotation direction is
OR gate 8 after setting the forward rotation to "1" by data 810
Data input terminal 805a of D flip-flop 805 via 11
Is input to Next, Q of shift register 803_TwoOutput 803c
And Q_ThreeThe exclusive OR of the output 803d makes the EX-OR gate 812
The rising edge of the direction determination pulse 813a, which is the output,
At the same time as the direction determination pulse 819a from the register 804
D flip-flop through EX-OR gate 814 to prevent
It is input to the clock input terminal 805b of the tip 805. And
D flip-flop 805 at rising edge 214 of clock signal 821a
Set the direction signal 805c, which is the Q output of the
Input to the up / down switching input terminal 806b of the counter 806.
To count up / down counter 806
State. Next, at the rising edge 215 of the clock signal 821a,
Q of shift register 803_ThreeOutput 803d and Q_FourExclusive theory of output 803e
The count pal that is the output of the EX-OR gate 813
813a rises and counts from shift register 804
Through OR gate 815 for ORing with pulse 820a
Input to clock input terminal 806a of up / down counter 806
Up count is performed by force. And up / da
The output of the counter 806 is output by the output terminal 806c.
It is output as information on the rotation angle.   Also, when the rotating body rotates in the opposite direction, the EX-OR game
The gate of EX-OR gate 809 is used by the output 807a of
Of the other party when the A-phase signal 801a rises and falls
That is, the logic value of the B-phase signal 802a is checked. And EX-OR gate
Set the direction determination pulse 812a, which is the output of 812, to "0"
In response, the up / down counter 806 counts in the opposite direction.
In other words, a countdown is performed. Also in FIG.
In circuit, rise of B-phase signal 802a by shift register 804
Rotate just before counting for both rising and falling
Find the direction. However, in the case of the positive direction in FIG.
In this case, the A-phase signal 801a is ahead of the B-phase signal 802a.
Therefore, the signal output from the EX-OR gate 818 is
The opposite of the logic value of the output of port 809. Ie square
It becomes “1” in the opposite direction and “0” in the opposite direction.
The up / down counter of the up / down counter 806
In accordance with the up / down switching logic of the
Therefore, there is no need for inversion by an inverter. Therefore
EX-OR gate 818 for checking the logical value of A-phase signal 801a
Is output to the OR gate 811 as it is. OR Ge
Port 811 is a pulse of the A-phase signal 801a and the B-phase signal 802a.
Rotation direction discrimination for both rising and falling
Provided to do.   According to the present embodiment as described above, the correctness of the rotating body
Each time counting in both direction and reverse direction,
Direction confirmation pulse 812a
From the clock oscillator 821 after the rise and the direction is determined
Up / down count after one cycle of clock signal 821a
Counter 806 counts, so
Make the frequency of the signal 821a sufficiently higher than the frequency of rotation of the rotating body.
By setting it high, the rotation angle can be measured without error.   In this case, the direction signal 805c is denoted by reference numeral 400 in FIG.
Corresponding to the signal indicated by
The output 806c is a high-resolution signal indicated by reference numeral 401 in FIG. 4 (b).
Is equivalent to   The clock oscillator 821 is indicated by reference numeral 122 in FIG.
Can be used as shown clock pulse generator
You.   Next, preset counters 115a, 115b and 115 are read from the memory 114.
The calibration value set in c will be described. As aforementioned
A that is included up to the change point of the Nth absolute signal
Cumulative number of increment signal N_incIs defined as in equation (1)
It is. (However, at the 15th and 16th absolute change points,
They are set to 200 and 315, respectively. )   Also, the absolute position of the change point of the Nth absolute signal
Z_NIs the resolution of the increment signal θ_minThen
Equation (2) is obtained. Z_N= N_INC× θ_min                           … (2)   The counter of the preset counters 115a, 115b, 115c in this embodiment
The count, ie, the up / down counting signal, is obtained by setting the increment signal to 4
It uses the signal 401 which is doubled, and the increment signal 1
In this configuration, four counts are performed. Accordingly
Included up to the change point of the Nth absolute signal
The number of unds is as shown in equation (3).   This count N_CThe absolute position corresponding to
Resolution is θ_minIs equal to equation (2)
You.   The absolute position corresponding to the change point of each absolute signal
The calibration value has the form of equation (3). For example, the fifth
The calibration value corresponding to the change point of the bus signal is 60 or 6.
At the change point of the absolute signal of the eye, for example, 84 in decimal
It has become.   At the transition point of the sixth absolute signal described earlier,
When the throttle valve 24 opens further after calibration, the direction
Signal 40 is sent to preset counters 115a, 115b, and 115c.
0, and the preset count is set every 1/4 of the recording pitch λ.
Counters 115a, 115b, 115c are added to 85,86 ……
Go. When moving in the closing direction, signal 400 becomes a down signal and
The number of counts is set to 83,82... Every quarter of the recording pitch λ.
... and subtract.   As described above, the preset counters 115a, 115b, 11
The current absolute position can be precisely
You can know in degrees. The number of counts is 501 to 512 terminals
Has been output.   Also, the increment signal is multiplied by k and the preset count is
N-th when inputting upper and lower counts of data 115a, 115b, 115c
Calibration value N corresponding to the change point of the absolute signal of_kIs
Equation (4) is obtained. N_k= KN_INC                              … (4)   In this embodiment, the absolute data stored in the memory 114 is used.
The numerical value assigned to each change point of the
The cumulative number of increment signals (eg, A phase) up to the point
Stored. However, preset counters 115a, 115b, 115c
Counting is performed at four times the increment signal.
L-shaped lower 2 bits of reset counters 115a, 115b, 115c
Of the calibration value output from the memory 114 at the third bit
Correspond the least significant bit and multiply the value in memory 114 by 4
Configuration of preset counters 115a, 115b, 115c and
I have. This allows equation (3) to be written as
Because. N_C= 2^Two・ N_INC                              … (5)   The values in the memory 14 are high-resolution signals up to each change point.
That is, the counting of the preset counters 115a, 115b, and 115c is performed.
It may be the cumulative number of signals. At this time,
Each bit of the memory 114 and preset counters 115a, 115b, 115c
What should I do?   The concept of the present invention is limited to the above equations (1) to (5).
Not something. As mentioned earlier, the absolute signal
Each transition point can be selected arbitrarily, and the length between each transition point is
Anything that consists of an integral multiple of the number of high-resolution signals is good.
No. Change point 15,1 of absolute signal shown in this embodiment
6 is an example.   That is, according to the above equation (3), the calibration values at the change points 15, 16
Are each However, in this embodiment, at the 15th and 16th change points, N_Fifteen'= 4 × 200 = 800 N₁₆'= 4 × 315 = 1260 It is configured so that   In this embodiment, the operation range of the throttle valve is 90 degrees.
In this case, 315 × 4 = 1260 increment signals are generated.   From 0 to 30 degrees, 14 increments per deg
An interpolation signal is generated to interpolate the absolute signal.
Therefore, the increment signal during this period is 105 × 4 = 420
is there. Between 30 degrees and 90 degrees, the increment signal is (31
5−105) × 4 = 840 pieces are generated. Therefore, even in this section, 1
Increment signal during deg Occur.   After all, in the present embodiment, 14 points are set based on each change point.
The detection angle increases by 1deg every time the increment signal is added
Alternatively, it is configured to decrease.   The point of change is a low throttle valve opening example (30 degrees or less)
Box), the calibration is performed frequently for the following reasons.
by. 1) Set detection of calibration value of initial position of throttle valve
, Especially in the low opening range. This section
In this case, the throttle valve opening information is used for fuel control and other functions.
It has a large effect on the control of the seki
Need to be 2) In the low opening range of the throttle valve, increment
It is permissible that the signal counter value goes out of order due to a counter mistake etc.
Not. For this reason, calibration must be performed frequently using absolute signals.
So that even if something goes wrong, it can be returned to a normal state early.
I do.   Note that the absolute value is not used for interpolation.
When used as a solute type sensor, the structure of this embodiment is used.
Is particularly important.   In other words, like a throttle valve, there is a certain
If it is necessary to improve the detection resolution in the
Change point of absolute signal is approached in specific section
It is important that they occur. Absoleil like this
In order to output the port signal with unequal pitch,
As in the embodiment, the element patterns are arranged at irregular intervals.
Achieved by   In the case of this embodiment, the absolute signal is up to 30 degrees.
14 points of change are formed by unequal pitch,
By the way, there are only two changes. Idea of this embodiment
According to the first section, the absolute signal at 0.25 degrees
Changes, and the absolute signal at 0.75 degrees in the second section
Can be changed.   That is, the designated angle in each section (n = integer) is It can be configured so that   By the way, during n = 6 (sixth section) For n = 14 Becomes   The coefficient 1/4 at this time is the lower limit of the detection capability of the detection element.
Is set. In the above explanation, 1/4 of one detection is possible
The case where an element is used is described.   Also, depending on the resolution required by the controller, this coefficient
Can be changed.   Reset counter to return to the next position and indicate the absolute position
The processing of the output from the data 115a, 115b, 115c will be described.   In this embodiment, the signals of the preset counters 115a, 115b and 115c are
The signal is processed by the pulse duty circuit 599 and output.
Details of the processing will be described with reference to FIGS.   Absolute position outputs 501 to 512 are one of EX-OR gates 110f to 110R.
To be entered. The other input of EX-OR gate 110f to 110R
Is a duty output inverted signal 608. 115d ~ 1
15f is a preset up down counter, and
In the E circuit 599, it is used as a down counter.   The clock signal 204 is input to 115d to 115f and
When a carry occurs, NOR gate 619 (for example, RCA CD4
The output of the standard logic IC such as 025 is in the H state. This
This state is referred to as point a in FIG. 10 for explanation. Carry signal 604
Is set to the data input terminal of the D-flip-flop 121c.
The signal is input to the signal terminal and the D-flip-flop 121c
The preset signal 605 rises from the output terminal of the switch. This signal 6
05 is the clock signal of the D-flip-flop 121d at the same time.
And inverts the signal at output 606. At the same time
Tee output inversion signal 608 is also inverted by inverter 118d.
You. The above is the operation at the point a.   Then, when the preset signal 605 rises, the
At least one of the carriers 115d-115f will disappear
The output 604 of the NOR gate 619 changes from H to L.   Next, at the point a ', the clock signal 204 is converted by the inverter 118c.
The inverted signal 609 is the clock of the D-flip flop 121c.
When the preset signal 605 is set to H
From L to L, and the outputs of the EX-OR gates 110f to 110R are
Are set to counters 115d to 115f. Set at this time
The data is such that one input 608 of the EX-OR gates 110f to 110R is L
, The preset counters 115a to 115a
The output states 501 to 512 of 5c are set as they are. This set
The output data is output to counters 115d to 115f as clock signal 20.
4 decreases every time 4 is input.
Carry signal 604 is generated at the input of the signal in the same way as point a.
You. The output 606 of the D-flip-flop 121d changes from H to L.
And the duty output inversion signal 608 is inverted from L to H.
You. The output of the EX-OR gates 110f to 110R again at point b '
Are set in the counters 115d to 115f. At this time set
The input data is one of the inputs of the EX-OR gates 110f to 110R.
When a certain duty output inversion signal is in H state
Counters the outputs 501-512 of the preset counts 115a-115c.
The inverted signal is set. This signal is also the counter 115d
~ 115f, decreases every time the clock signal 204 is input.
Eventually, a carrier is generated at the position indicated by point c in FIG.
The next data to counters 115d to 115f
Set. The data at this time is inverted for the duty output.
Since the signal is L, the state of the outputs 501 to 512 remains unchanged.
It is set.   In the above operation, from the point a to the point b, the counter 115d
~ From 115 in 12 bit range formed by 115f to absolute position output 501 ~
It corresponds to 512 counts, and from point b to point c is a 12-bit range.
The time corresponding to the remaining count number in the box is reached. Obedience
From point a to point c is always constant and absolute position output 50
The point b changes according to the state of 1 to 512.
The output 606 of the flip-flop 121d is taken out via the signal line 10b.
In this way, the opening degree of the throttle valve 24 is changed to a duty cycle at points a to c.
Obtained as an e-signal.   Also, the opening signal of the throttle valve 24 is transmitted by one signal line 10b.
By taking it out, the control unit 21 shown in FIG.
Are connected to the power supply line 10a and the ground
The function can be determined by the three lines of the signal line and the signal line 10.   As described above, the magnetoresistive element was used for one embodiment of the present invention.
Although an example has been described, the present invention relates to position detection using a photoelectric element.
The output device can be similarly configured.   FIGS. 25 and 26 show another embodiment using a photoelectric element.
is there. This embodiment is also applied to the throttle sensor described above.
In the above example, the Nth absolute signal
The relationship between the number of increment signals included up to the point of changeThis is an example. Center of rotation O in slit disc 900
A phase, B phase, 2 in order from the inner side on the concentric circle as the center⁰, 2¹,
Two^Two, 2^ThreeArrangement.   The light emitting elements 901a to 901f and the light receiving elements 902a to 903f are respectively
The slits are located opposite the slits, and
Slits on the slit disc 900 connected to the body
The configuration is such that the pair position can be detected.   The signal processing circuit shown in this embodiment has analog and digital signals.
But the current technology such as ASIC (application
Angle detector can be integrated by using specialized IC)
Built-in inside is also possible.   Hereinafter, the configuration, operation, and effect of the present embodiment will be summarized.
Is as follows. (1) Detect changes in the absolute signal, and
Pre-assigned numerical values (calibration values) from memory
Set the counter. In addition, the rotation direction
Signal (upward) or down signal (downward)
The high resolution signal is used as the upper and lower counting signal of the counter.
You. (2) Even if the absolute signal is the same data,
Data obtained by increasing direction change and decreasing direction change
If the data is the same, the data changes even if the data is the same
The point, that is, the change point of the absolute signal is different. Follow
Change direction even if the absolute signal is the same data.
Absolute position by numerical value different for each
Storage, comparator, addition
, Memory, presettable up-down counter,
It is composed of a timing circuit. (3) Set each change point of the absolute signal to an arbitrary position.
I can. (4) The counter is set at each change point of the absolute signal.
The values that are printed are absolute position information corresponding to each change point.
You. At each change point, set this value in the counter
The absolute position is calibrated with
Adds or subtracts the number of high-resolution signals to the position information according to the direction of rotation
The current configuration depends on the data in the counter.
Can be detected with high resolution. Cow as a specific example
The value set on the printer varies from the origin (initial position)
Consists of the cumulative number of high-resolution signals representing the angle to the point
Therefore, the current absolute position is represented by the value in the counter.
High-resolution absolute position detection.
Wear. This is because each change point of the absolute signal has high resolution
Because the configuration is generated by an integer multiple of the signal,
The absolute position can be detected by using the counter
You. (5) The signal processing circuit described above modulates the absolute signal.
Is detected by the comparator, and if the
An absolute signal is given to the memory as an address.
On the other hand, if the change occurs in the down direction, a new
Add 1 to the busolit signal to obtain the memory address
Increase or decrease for the same data of the absolute signal
Different values depending on whether it occurred in the direction of displacement
Absolutely set to preset up and down counter
Since the position is calibrated, any direction change occurs, either increase or decrease
However, accurate absolute position calibration can be performed. (6) Arbitrary change point of absolute signal is provided
In the predetermined section, the change points of the absolute signal at equal intervals
A change point configuration having a lower pitch than the interval can be provided.
Therefore, the absolute change point generated at low pitch
High-frequency calibration can be performed and a highly accurate detection area can be set.
Can be opened. (7) Calibrate the absolute position at the changing point of the absolute signal
The absolute position is detected using a high-resolution signal until the next change point.
Get out. Therefore, the absolute signal is absolute position calibration
It can be used in a low pitch configuration.
You. 〔The invention's effect〕   According to the present invention, (1) Using low-bit absolute signal and high-resolution signal
Absolute position detection with high resolution equivalent to a high resolution signal.
And an angle detector that can be provided. (2) High resolution absolute position detection is possible with low bit configuration
Therefore, the size, weight, and cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 (a) and 1 (b) are illustrations of the state of generation of a signal obtained according to an embodiment of the present invention, and FIG. FIG. 3 is a development view of the resistance element, FIG. 3 is a bridge configuration diagram of the magnetoresistive element of FIG. 2, FIG.
(B), FIGS. 5 and 9 are signal processing circuits, and FIG.
FIG. 7 is a time chart of the signal processing circuit shown in FIG. 7, FIG. 7 is an explanatory diagram of the operation of the signal processing circuit, FIG. 8 (a) is a detailed diagram of the direction discriminating circuit and the multiplying circuit, and FIG. Figure,
9 is a detailed diagram of a duty circuit, FIG. 10 is a time chart of the signal processing circuit of FIG. 9, FIG. 11 is a longitudinal sectional view of a throttle sensor suitable for one embodiment of the present invention, and FIG. FIG. 13 and FIG. 14 are characteristic diagrams of the engine, and FIG. 15 to FIG.
The figure shows the principle of detection and operation of the magnetoresistive element.
FIG. 26 is a drawing showing another embodiment in which the present invention is constituted by photoelectric elements. 1, 1a drum, 2, 2a substrate, 9 signal processing circuit, 20 throttle sensor, 24 throttle valve, 111 rat, 112 comparator, 113 adder, 114 memory, 115a to 115f ... Preset counter, 117 ... Timing circuit, 123 ... Direction determination circuit, 170 ... Initial setting circuit, 599 ... Duty circuit, 900
… Slit disk, 901a-901f… Light emitting element, 902a-902f…
Light receiving element.

   ────────────────────────────────────────────────── ─── Continuation of front page    (56) References JP-A-58-93936 (JP, A)                 JP-A-53-56062 (JP, A)                 62-56739 (JP, U)                 Shokai Sho 62-7008 (JP, U)                 Tokuyo Sho 63-500557 (JP, A)

Claims (1)

(57) [Claims] Means for generating an absolute value signal corresponding to a specific rotation angle of the throttle valve of the internal combustion engine, wherein the throttle valve generates the absolute value signal more densely in a low opening region than in a high opening region; A throttle, comprising: means for generating an increment signal at a predetermined interval in accordance with the rotation of the valve; and means for obtaining the rotation angle of the throttle valve by interpolating the absolute value signal with the increment signal. Valve rotation angle detector. 2. An absolute value signal is generated more densely in a low opening region of the throttle valve than in a high opening region in accordance with a specific rotation angle of the throttle valve of the internal combustion engine, and an increment signal at a predetermined interval according to the rotation of the throttle valve. Wherein the absolute value signal is interpolated with the increment signal, and the rotation angle of the throttle valve is obtained based on the interpolated increment signal.