JPS599713A - Position detecting system - Google Patents

Abstract

PURPOSE:To obtain a position signal which is precise and having scarcely a ripple, by detecting a detecting level of two signals different in 1/4 period phase generated in accordance with movement of an object which moves or rotates in two directions, by subdividing it as to its position. CONSTITUTION:A motor 1 rotates and a rotary encoder 2 generates signals A, B of two phases different in 1/4 phase each other. A clock oscillator 17 generates a clock pulse of high frequency from the signals A, B, it is counted by counters 18, 24, and a digital value is outputted from ROMs 19, 25 in accordance with a count value. An amplitude value of a position which divides equally one period of the signals A, B into 16 is stored in the ROMs 19, 25, its read-out data is analogized by D/A converters 20, 26, respectively, is compared with the signals A, B by comparators 21, 27, and in accordance with its result, the counters 18, 24 are added and subtracted, and follow the signals A, B. A signal being near an amplitude center level is selected by a selecting circuit 23, a multiplexer is controlled, a direction is detected by a direction detecting circuit 49, and a position signal is outputted from a counter 45.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention is directed to the mowing of an object that moves in two directions or turns in one direction. j
, I) of the periodic single generated by the detector in response to
According to the D publication, it is related to the method of detecting keratin after 1 h, and it is driven by a motor or a motor in 41! The first 4 books (υ11)
- Change the old number to the position detection method obtained by the inertia number with less ripple.

(b) Prior Art and Problems As a method for detecting the position of a motor or an object driven by a motor, a method using a rotary main encoder or the like is known.

Example kJ' rotary encoder is motor rotation l1jI
A few words were asked by l, and the rotation 11 QI! A two-phase pseudo sine wave (i4
This two-phase signal A has a frequency similar to a sine wave signal and is proportional to the rotational speed of the motor.

B's trigram') 1 like sine n'; From the I word to the object's (i'f
: crying signal (1, [normally lower,) 12 no 4111 (, f:
',,−,is issued.

7.% 1 Figure 16 and the previous Nj pseudo sine wave signal to 1. ′
101 is a schematic diagram of generating a symbol. FIG. 2 shows waveform 1 of the first diagram. -ε-Meta rotates once and the rotary encoder 2 generates a signal A having 2 phases, 1) and 1 phase.
and No. 111 I3 are generated and sent to the signal Aυ comparator 3 +kf
-'f3' B enters comparator 4. Ratio 1...S3 is °1" if signal A is greater than O volts, and 01 if it is smaller.
The monostable 5 generates a pulse at the rising edge of the output of the comparator 3, and the monostable 6 generates a pulse at the rising edge of the output of the comparator 3. If the signal B is 0 +M silt, it will generate a signal of "11. If it is small, a signal of °O1 will be generated, and all the pulses will be generated at the rise of the output of the monostable 7 ratio 11 ratio generator 4, and the monostable 8 generates a pulse at the falling edge of the output of the comparator 4.The outputs of the monostaffles 5 and 6 are logically summed by the OR circuit 10, and
The outputs of the monostable 7.8 are logically summed by an OR circuit 11, further logically ORed by an OR circuit 12, and output to a counter 1.
4, and at the falling edge of the pulse, the counter 14?7+, i
1 round Q saoluru. Add A, Mix, R, or d Exclusive OR times 1, 9, 13 output (・7. Then, the rotational force direction of motor 1 is ij
I will do it. Reset pulse generator 16
If you make 11 works, the counter will be 14 (c) 1 rehinote. If motor 1 starts turning +1ii clockwise after -, the output of ratio i:s3.4 will change every time 1τ=h, n cuts 0 volts to ]J, and the output of monostaffle 5.
li.

At 7.8, a pulse is generated. Af Hals & J, former G
Input color like L to 14, υ; other ORl+, 4
Since it becomes the output phase 111 of the i-path 13, the counter 14 continues to be weighted. The output of the counter 14 is outputted as a stepped pressure waveform by the digital-to-analog converter 15. Also, when the rotation direction of the motor 1 is reversed and rotates counterclockwise, the output of the exclusive R circuit 13 is 101 and is counted by the counter 14 i, i it n.・f[
1<Output of the digital-to-analog converter 15 (・This is a position signal indicating the rotating part of the motor 1 at the stage where the set pulse generator 16 is operated.

According to such conventional technology, the position signal is signal A.

The upper pressure waveform has a step-like shape with a period unit of 13.741
It's rare. Therefore, it is conceivable that the number of slits for measuring the rotational position of the motor in 4# density can be expressed as il:itl. However, this (・;10-Tari''-Nkota's single stack is made into a high one, and from a historical perspective;--Lit number is
There are drawbacks such as there are limits to how much it can be added to.

(C) Aspect 1 of the invention In order to eliminate the above LL defect, one period of the pseudo sine of the rotary encoder is fixed at regular intervals; Then, by storing the corresponding amplitude value in a memory circuit and using it to track a pseudo sine that changes by 1, a digital circuit counts the equal intervals divided into 11 as the minimum unit, and calculates the ratio of the tracking circuit. Only when the output of the soft circuit is active for two clock cycles and is the same, the υ position signal can be increased by increasing or decreasing the numerical aperture I11 of the digital circuit. An object of the present invention is to provide a method for detecting M that reduces the amount of M.

(d) Structure of the Invention The structure of the present invention moves in two directions if; One round of phase iG A or LIB
means for storing the amplitude value for the position; G-1's output is completely digital/analog convertible! , ``A means for absorbing the amplitude of A or B, and a clock pulse of -J?, period jv] is applied to the output of the ratio means, and ↓゛-0 or -1 is expressed, 13fJ
1:l:f! 121-・dI that makes a pukhiss on the “・” stage
Means A and B for comparing the following circuits 11 and 1iA and B obtained from several means, and the outputs of the following circuits A and B, and the 11th positions corresponding to the own and loquats of the circuits A and B. A means for determining the direction of movement of the object from the output of the object, and a means for calculating the number of the motion meter only when the object outputs a recess 1 or a logical O are capable of making i-1 numbers. It is something.

(e) Embodiment of the invention FIG. 3 is a circuit diagram showing one example of the present invention Mfi (611), and FIG. The clock generator 17 generates 4+ clock pulses with a frequency Z that is sufficient for changes in the signals A and B. Generates.Memory 1
For example, lLOM is used for 9 and 25, and as shown in FIG.
: Shake-value MO-M15 for 1 o ~ 115
When the output of the memory 19 is converted from digital to analog by the /A converter 20, the amplitude value of the signal A obtained by multiplying the value of the counter 18 by 5 is obtained. ~ Any one of M15 will be housed as a DACA. In the comparator 21, the amplitude value of the signal A sent from the rotary encoder 2 and the amplitude value DACA read from the memory 19 are compared by 11.
If the information is greater than A75KDACA, it becomes I11, and the four values of counter 18 are added>i. That is, addition is performed using the clock from the clock oscillator 17.

If the signal A is smaller than 1) ACA, the output of the ratio softener 21 is 1
() What about e and 7-recounter 18? Decreased by 9 due to missing clock pulses. Counter 8 number 1'] Moromi'ko, the amplitude value of MO-M15 of Shiri memory 9 is 'WJr,
111sa)]Z) Therefore, DACA follows the waveform of signal A while taking any 1111 of MO-M15. That is, counter 8. Memory 9. I)/A Shunshuki 20. The ratio IK i21 constitutes an il, f slave circuit A47. The same goes to the counter 4. Memory 25, 1)/A inducer 26.
The comparator 27 constitutes a follow-up circuit B4N3. The follow-up circuit B48 is similar to the follow-up circuit A47 except that the signal waveform to be compared with the operation +j is the signal B. i.e. D/A
The output L)ACB of the f converter 27 follows the waveform of No. 11B. Therefore, the relationships 13-j between the signals A and I)ACA and between the signals B and ])ACB become as shown in FIG. 4, and the outputs of the comparators 21 and 27 also change as shown in FIG. The output of the comparator 22 is Wll if the waveform of the signal A is more than 0 volts, and 0° if it is less than 0 volts. Similarly, the output of the non-comparison 28 is also the signal I3.
If the waveform of is more than 0 volts, then 11@, small is lOf
becomes.

FIG. 6 is a detailed circuit diagram of the A, B selection circuit 23.

The output of the counter 18 is M4 (f, Figure 5), and the ratio φ is 1. Ll force is 111, χ is counter 1
The output of 8 is Mll, and the output of the eye-to-articulator 21 is 10.
When it is 1, the selection signal USFjA is hit. Either the output of the counter 18 is M3 and the output of the comparator 21 is 101, or the output of the hft counter 18 is M12, and the ratio φ'
(When the output of the counter 21 is 111, the selection number 16 USEA is reset. That is, when the output of the counter 18 is M4,
Decoder 5011-1: Terminal 104 is set to 111. Since the output of the compound/container 21 is 11 degrees, the AND circuit 1 circuit 52 is 1
11, and the JK flip-flop 58 is set via the OR circuit 56. When the output of the counter 18 is Mll,
The terminal 111 of the decoder 50 becomes 111, and the comparator 2
Since the output of 1 is 101, the NOT circuit 51 becomes 111, which becomes an AND circuit 53&Wll, and sets the frinobuflrough ``58'' in the same manner as above.The output of the counter 18 becomes ``f'' of M3, and the terminal 103 of the decoder 50 becomes 111. , since the output of the comparator 21 is 101, the NOT circuit 5
The output of 1 becomes "1'fAND circuit 541d'l',
After the OR operation M&57, the free lag flop 58 is reset. When the output of counter j8 is M120, Tekota 50
becomes tJ@ at the terminal 112 of , and the output power of the comparator 21 becomes 1
Therefore, the A N D IIE circuit 55 becomes °11, and 1
111. A.j Set the clip flop 58. For kneading, use the range shown by the arrow in Figure 5 to find the center level of the 1H A or signal BOVpt where the pressure level difference is relatively large and the amplitude difference is good: 1. It is used to adopt information in a close range.

The output of the comparator 21, that is, the follow-up circuit 471: The output is D
When the output of the comparator 21 is '11' continuously in the flip-flop 29 for two periods of the clock period, the AND
The circuit 35 becomes 111, and conversely, when the output of the ratio divider 21 is the, the output of the comparator 21 and the output of the D clip-flop 29 become 101, and the output of the circuit 35 becomes 111. ,
31 and 32, AND circuit 36t', 1'',!=f.
,i,' J:lZ i,11! If the output of the multiplexer 21 is 11 m or 01 for two clock periods, it becomes 111, and if the output of the non-comparison 21 does not repeat 11 Z 701 every clock period, then it becomes 101 and the multiplexer Enter 43. The output of the comparator 27, that is, the output of the follow-up circuit 48 enters the D flip-flop 30,
AND circuits 37, :38, N0Tl paths 33, 34 and O
The R circuit 40 inputs logic 111 to the multiplexer 43 if the same output from the comparator 21 is "11 or l□f" continuously for two periods of the clock cycle.
'1' every clock cycle, '0' when returning °01
Enter 1. A, Bbi selection circuit 23 output USgA&
- OR circuits 39 and 40 by switching J multiplexer 43
Send either of the outputs. This output is as above,
An iH signal in a range close to the center level of signal A or B is selected and sent to counter 45 as a count enable signal. The counter 45 has a count enable signal of 1.
Clock pulses are added or subtracted only when the clock pulse is 11. That is, the change in the signal A or -B selected by the selection signal USEA is small and the counter 18 or 24 of the follow-up circuit 47 or 48
(j) repeats addition and subtraction, the egress value of the counter 45 does not change.

The output of the AND circuit 35 and the output of the comparator 2g enter the exclusive OR circuit 41, and the output of the AND circuit 38 and the comparator 2
The output of 2 is input to the exclusive OR circuit 42, and the selection signal USE
If A selects the information on the signal A side, the multiplexer 44
When the output of the exclusive OR circuit 41 is selected by 4 on the signal B side by controlling the output of the exclusive OR circuit 42, the output of the exclusive OR circuit 42 is
Send to. The abstract OR circuits 41, 42 and the multiplexer 44 form a direction detection path 49 for detecting the direction of motion of the object. That is, the output of comparator 22.28, AN
The rotational direction of the motor 1 is detected from the outputs of the D circuits 35 and 38 and the selection signal USEA, and the counter 45 is controlled to add or subtract.

The counter 45 sends the h'I value after being reset by the reset puff of the reset pulse generator 16 to the D/A converter 46, and outputs the h'I value to the D/A converter 46, as shown in the position signal of FIG.
The digit 1ξ signal is sent at a 1-section pressure value with less ripple.

It should be noted that normally, due to eccentricity of the rotary engoder 2 with respect to the rotating shaft, the extremely large amplitude values of the signals A and B slightly increase or decrease in the cycle of one revolution of the motor 1. When this influence cannot be ignored, a circuit 11.1 for detecting and holding the extremely thick value is added to the D/A converter 20.1 of the follow-up circuit 47.48. '26 output is modulated with the magnitude of the local maximum value. That is, the peak detection and holding circuit 59 and multiplier 60 shown in FIG. 7 are added to the circuit shown in FIG.
By adding 4, a more precise position signal can be obtained.

In this embodiment, one period of signal A or B shown in FIG.
It was divided into six equal parts, and the more the number of equal parts, the more precise the position signal becomes. Therefore, the number of divisions can be determined as necessary.

(f) As described in detail, the present invention Q detects the change in the pseudo sine wave signal generated by the rotary encoder by subdividing the detection level with respect to the position, so that it is possible to achieve precise VC and ripple-free detection. It is possible to obtain a position signal that detects the rotational position of the motor. It has the flexibility to rewrite or replace the contents of the memory circuit (memory) even for rotary encoders whose pseudo sine wave signals have different waveforms. In cases where the rotational position of a motor is to be detected precisely, a very effective effect can be obtained.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram for generating position I [;
Fig. 3 is a circuit diagram of one embodiment of the invention (H), Fig. 4 is an explanatory diagram of the operation of t'M Fig. 3, Fig. 5 is a diagram explaining the recorded contents of the memory, Fig. 6 is A, A detailed diagram of the B selection circuit, FIG. 7, is a circuit diagram for eliminating the influence of eccentricity, etc. of rotation i+11. 1σ motor, 2-: rotary encoder, 3 and 4 are comparators, 5 to 8 are monostables, 14 is a counter, 15 is a D/A converter, 16 is a cent pulse generator, 17 is a clock generator, 18, 24°45-counter, 19.2
5 is memory, 20,26°46 is D/A converter, 2
1, 22, 27 and 28 are comparators, 43 and 44 are multiplexers, 5o is a decoder, 59Fi peak detection and holding circuit, and 6o is a multiplier.

Claims (1)

[Claims] Means for digital-to-analog conversion of outputs generated by the detector in response to the motion of an object moving or rotating in two directions, each having a phase difference of 0 period, and comparing it with the amplitude of the signal A or B. and a divisor means for adding or subtracting clock pulses of a constant period according to the output of the comparing means and accessing the storage means; and the following circuit A;
and a selection signal for selecting the one of the slave circuits A and B that is closer to the amplitude center level of the signal A or B;
means for determining the direction of movement of the object from the outputs of the means A and B for comparing the potential of each amplitude of the signals A and B with respect to a zero potential, and means for counting the amount of momentum of the object,
Only when the follow-up circuit A or B continuously outputs logic 1, logic 1, or logic 1 over 21 periods of the clock pulse, it is possible to provide a number of sets of means for calculating the HI-number of the previous 1j'2 motions. This is an I☆vulgarity detection method that is characterized by the following.