CN1240928A - Capacitance encoder - Google Patents
Capacitance encoder Download PDFInfo
- Publication number
- CN1240928A CN1240928A CN 98115362 CN98115362A CN1240928A CN 1240928 A CN1240928 A CN 1240928A CN 98115362 CN98115362 CN 98115362 CN 98115362 A CN98115362 A CN 98115362A CN 1240928 A CN1240928 A CN 1240928A
- Authority
- CN
- China
- Prior art keywords
- electrode
- circuit
- width
- testing circuit
- pair
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Transmission And Conversion Of Sensor Element Output (AREA)
Abstract
A capacitance encoder comprises increment type and absolute type. In its circuit CMOS device is used, resulting easy integration, simple structure and technology and low cost and power consumption (micro power consumption). It can be widely used to detect and control the displacement and position in industrial production, such as numerically-controlled machine-tool, machining center, robot, autocontrol system, domestic electric appliances, engine crankshaft, etc.
Description
The present invention relates to grid shape electric capacity (be called for short and hold grid) sensor, and be the capacitive transducer of changed area, detect two relative straight lines of object or swing offset or position quantity with the differential capacitor variable quantity, particularly can high-precision measurement big displacement quantity.
In patents (as GB2139359A) such as Germany and Britain, the circuit of the capacitance encoder of elaboration and structure are all comparatively complicated.According to market survey, in states such as U.S., moral and Japan 1,000,000 above photoelectric encoder markets are all arranged every year, but photoelectric encoder also exists shortcomings such as manufacturing is complicated, price is high, power consumption is big.
The present invention is directed to above-mentioned shortcoming, the manufacturing process of further performance appearance grid is simple, cost is low, advantages such as (little power consumptions) low in energy consumption, proposes a kind of than existing capacitance encoder and photoelectric encoder circuit and capacitance encoder simple in structure.
The scrambler branch has two kinds of incremental encoder and absolute type encoders.Existing division is as follows.
Being described below according to increment type capacitance encoder provided by the present invention, for ease of explanation, is that example is described in detail with straight-line increment type capacitance encoder.The increment type capacitance encoder is made up of physical construction, sensor and testing circuit.Physical construction has pedestal and slide etc.; Sensor has the fixed plate and the movable plate electrode of opposing parallel motion, electrode on fixed plate is wide and equidistant the arrangement, two pairs of electrode groups are arranged on the movable plate electrode, every pair of electrode group has two arrays of electrodes, two pairs of four groups of electrodes that the total electrode number of electrode group equates, the width of every group of electrode is identical wide and equidistant the arrangement with arrangement and fixed plate top electrode, the arrangement of every pair of two arrays of electrodes by the inventor's ZL86106551.4 patent of invention given differential change queueing discipline arrange, every pair of two groups of capacitance variations are differential change.The insulation width of two pairs of electrode group adjacent electrodes is T
s/ 4 (T
s=a
s+ b
sPitch, b
sElectrode width, a
sInsulation width between adjacent electrode), therefore two pairs of differential change output waveforms also differ T
s/ 4, this discriminating direction factor is arranged, when guaranteeing the relative fixed plate operation of movable plate electrode, the adding deduct of step-by-step counting, but the change of accompany movement direction, the conversion that adds deduct automatically.So-called movable plate electrode and fixed plate are meant relative motion, can conveniently exchange according to structure and operation, and promptly movable plate electrode can be fixed as fixed plate, and fixed plate is as the movable plate electrode of motion.The fixed plate and the movable plate electrode of the increment type capacitance encoder that rotatablely moves are annulars, it is represented with angle respectively corresponding to the fixed plate of straight-line increment type capacitance encoder and the electrode width and the insulation width of movable plate electrode, this straight line is identical with two kinds of pole plate electrode spread rules that rotatablely move, two kinds of testing circuits are also identical, testing circuit is the circuit that detects every pair of two arrays of electrodes group electric capacity differential change respectively, the testing circuit of two pairs of electrode groups is identical, detect the circuit of every pair of two arrays of electrodes group electric capacity differential change, control by the main oscillator that makes, a pair of identical electronic switch, resistance and single-ended in-gate circuit (phase inverter) are formed charging and discharge circuit periodically, pair of differential is changed electric capacity convert the pulse width amount that pair of differential changes to, through anti-phase, get a positive pulse and another rp pulse respectively and form two groups, comparison by two double input end gate circuits, draw two differences, trigger the R and the S input end of R-S trigger respectively, the output of R-S trigger is the square wave that the differential Changing Pattern of electric capacity changes when moving by movable plate electrode, when the relative fixed plate constant-speed operation of movable plate electrode, pairing square-wave cycle is proportional to the pitch (T of fixed plate top electrode
s=a
s+ b
s), another is to electrode group and testing circuit same as described above, and its R-S trigger is also exported the identical square wave that differs T/4 (T square-wave cycle) with above-mentioned square wave phase.Two groups of output of the square wave of these two groups of phase phasic difference T/4 and the photoelectric encoder of increment type square wave is identical.If PAL16R4 with the described three kinds of photoelectric encoders of 202-216 page or leaf in Zhu's generation letter programmable logic device (PLD) (PLD) special designs the 1st edition book in technology Electronic Industry Press January in 1994, PAL16R8 and PAL20X chip all can be connected by corresponding testing circuit of the present invention; Adapt programmed file a little, get final product adapted.
The absolute type capacitance encoder, sensor electrode is regularly arranged with " essence is taken aim at " by ZL86106551.4 patent of invention given " bigness scale ".Its testing circuit is also to having " bigness scale " and " essence is taken aim at " testing circuit.Two testing circuits are identical.The main order vibration and the differential variable quantity of electric capacity of this testing circuit are converted to the pulse width variation amount, pulse width through anti-phase and two differential change relatively waits link, identical with the testing circuit of above-mentioned increment type capacitance encoder, but the residual quantity of pulse width after relatively, be to trigger monostable circuit separately in the absolute type capacitance encoder, the absolute position point is to be selected in two electric capacity identical pointses that pair of differential changes, two electric capacitys changing of the pair of differential difference of pulse width after relatively of being converted to two differential change is zero like this, its corresponding each self-triggering monostable circuit is output as zero, and the rejection gate through double input end is output as noble potential again.When the output of the testing circuit of " bigness scale " and " essence is taken aim at " is all noble potential, through double input end with door or anti-phase respectively after and OR-NOT circuit be output as noble potential, this is the output signal of the aiming anchor point of absolute position point.
Advantage of the present invention:
1. sensor manufacturing process of the present invention is simple, and circuit is simple, and used electronic component is electronic switch and the gate circuit of using always, and product price of the present invention is cheap especially;
2. the present invention and similar existing capacitance encoder, compare in " capacitive character line style that the control of mobile thing and location are used or rotation transmitter " patent of invention (Republic of China's patent gazette is accused numbering 133470) of Taiwan application as German space feed Si Tele company limited, circuit and sensor electrode figure are all very simple;
3. the electronic component of circuit of the present invention is on-off element entirely, caused noise of no amplification system and cumulative errors, and stability, Repeatability and Reproducibility is good;
4. circuit of the present invention all CMOS special use is integrated, only need the 100-1000MOS pipe, be medium scale integration (MSI) (MSI),, only need the 100MOS pipe with sensor interface circuitry if connect programmable logic device (PLD) (PLD), be small scale integration (SSI), cmos element has antijamming capability strong, and operating temperature range is big, and operating voltage range is wide, low in energy consumption, button cell power supply volume is little, and the fine motion consumption helps the additional current failure memory link of increment type capacitance encoder;
5. the grid electrode width of sensor is being not less than under the situation of 0.30mm, and (mask-making technology of live width 0.30mm is existing common mask-making technology) can directly provide step-by-step counting, or improves revolving revolution output step-by-step counting, need not the frequency multiplication segmentation:
6. output waveform of the present invention is directly from the output of on-off element, than the good output waveform of photoelectric encoder.Requirements such as the electric property of capacitance encoder of the present invention and structural parameters can be made into identically with existing photoelectric encoder, are equal to the replacement photoelectric encoder, adapt to market demands.It is not only applicable to the Detection ﹠ Controling of displacement and position in the commercial production, as numerically-controlled machine, machining center, robot and various automatic control system; Video recorder in the household electric appliances, video camera, compact disc player and VCD or the like position control, as used elements such as photoelectricity, magnetic drum and Hall in the rotating speed control of servo-drive system, if use the present invention, not only circuit is simple, cost is low, and structurally also very simple; The brushless electric machine of servo system in video recorder (DD motor) for another example, if use the present invention, simple in structure, volume is little, the saving magnetic material.Also have in the automobile sensor, the crank position of motor car engine, the sensor that gasoline throttle angle is used is if all have a clear superiority at cost, volume, power consumption, limit of temperature rise and aspect such as anti-interference with the present invention;
7. the present invention does not have the required light source of photoelectric type, the shortcoming that does not exist its power consumption, life-span, response frequency and the ratio of performance to price etc. restricted by light source;
8. the present invention particularly makes special chip at same fundamental mode circuit, utilizes the combination of sensor to reach the output of raising shaft-position encoder revolution towards counting, and is easier than photoelectric encoder, and has a lot of potential advantages.
The present invention is described with reference to the accompanying drawings as follows by relevant necessary giving an example:
The straight-line sensor construction synoptic diagram of Fig. 1 the present invention;
The cut-open view vertical among Fig. 2 and Fig. 1 with the direction of arrow;
The cut-open view parallel among Fig. 3 and Fig. 1 with the direction of arrow;
The grid electrode figure of the straight-line incremental transducer fixed plate of Fig. 4 the present invention;
The grid shape electroplax figure of the straight-line incremental transducer movable plate electrode of Fig. 5 the present invention;
The corresponding line synoptic diagram of Fig. 6 incremental transducer fixed plate of the present invention and movable plate electrode top electrode;
The incremental transducer annular movable plate electrode that Fig. 7 the present invention rotatablely moves;
The incremental transducer annular fixed plate that Fig. 8 the present invention rotatablely moves;
Fig. 9 increment type capacitance encoder of the present invention testing circuit;
Figure 10 Fig. 9 testing circuit of the present invention is selected giving an example of another kind of element for use;
Figure 11 Fig. 9 testing circuit of the present invention is selected giving an example of programmable logic device (PLD) (PLD) for use;
Figure 12 forms the block diagram of the basic link of Fig. 9 pair of electrodes group testing circuit of the present invention;
Giving an example of the combined type annular fixed plate of the incremental transducer that Figure 13 the present invention rotatablely moves;
All there is the sectional structure synoptic diagram of fixed plate Figure 14 increment type capacitance encoder of the present invention sensor movable plate electrode both sides;
This bright absolute type capacitance encoder testing circuit of Figure 15.
Fig. 1 is two parts forming grid shape electric capacity linear displacement transducer, wherein movable plate electrode relatively fixed plate along the sensing parallel motion of F arrow.Fig. 1, among Fig. 2 and Fig. 3, distance between 1 fixed plate, 2 movable plate electrodes, fixed plate top electrode 3 and the movable plate electrode top electrode 4 is d, and fixed plate 1 is to utilize pedestal 5 to be installed on the not dynamic component 6 of tested parts, and movable plate electrode 2 is to utilize slide 7 to be installed on the movable member of tested parts (to draw among the figure).A among Fig. 3
sBe insulation width between the adjacent electrode on the fixed plate, b
sBe fixed plate and movable plate electrode top electrode width, a
s=b
s, pitch T
s=a
s+ b
s, the electrode group that has two pairs of electrode numbers to equate on the movable plate electrode, every pair of electrode that the electrode group has the two arrays of electrodes number to equate, these four groups interior each electrode width and the insulation widths between the electrode are all identical with the fixed plate electrode.Insulation width, i.e. a among Fig. 3 between two adjacent electrodes in the every pair of electrode group
1With b
1And a
2With b
2Between insulation width by inventor ZL86106551.4 patent of invention given differential change arrange existing then a
d=a
s+ b
s, the insulation width a between the two pairs of electrode group adjacent electrodes
t=T
s/ 4.This queueing discipline also meets the rule that the inventor points out, a in the ZL86106558.1 patent of invention
s=4b
o-b
s, a
t=3b
o-b
s, a
u=2b
o-b
s, in example of the present invention, b
s=2b
o(b
sBe the effective displacement width of each electrode), a
s=b
s, a
t=b
s/ 2=T
s/ 4 and a
u=nT
s(this routine n=0) is corresponding to a
d=a
s+ b
s=T
sAs seen, the queueing discipline of grid electrode still can further be inquired into, as the inventor described in the literary composition of " imagination of grid shape capacitance type sensor " (national sensor academic discussion in May, 1984 Wuhan), there's sth behind all this can do for these grid shape lines, also as pointing out in the U.S. Pat 4586260: capacitor type linear displacement measuring technique, also be not perfect, still needing makes it constitute capacitance sensor electrodes arrangement optimization.
The straight-line incremental transducer fixed plate of Fig. 4 the present invention grid electrode figure, the s end is lead end, ground connection or body contact in Fig. 9, the straight-line incremental transducer movable plate electrode of Fig. 5 the present invention grid electrode figure, a
1, b
1, a
2, b
2End is respectively lead end, is connected to the input end of phase inverter (gate circuit) in Fig. 9 respectively.B among the figure
sBe electrode width, a
sBe the insulation width between every group of adjacent electrode, a
d=a
s+ b
s=T
sBe every pair of insulation width between two groups of adjacent electrodes, a
t=Ts/4 is two pairs of insulation widths between the adjacent electrode.Fig. 6 is that the fixed plate and the movable plate electrode electrode pair of incremental transducer of the present invention answered the line synoptic diagram, wherein s, a
1, b
1, a
2, b
2End corresponds respectively to respective end and the line graph of Fig. 4, Fig. 5 and Fig. 9.
Fig. 7 and Fig. 8 are respectively the movable plate electrode and the fixed plate of the incremental transducer annular that the present invention rotatablely moves, s, a
1, b
1, a
2And b
2Respectively for the outer lead end described in Fig. 4 and Fig. 5, just Fig. 7 corresponding with Fig. 4 fixed plate electrode pattern is movable plate electrode, Fig. 8 of corresponding diagram 5 movable plate electrode electrograph shapes is a fixed plate, help the outer line that draws that rotatablely moves like this, outer lead S end is ground connection (or body contact) end, need not brush as the external lead wire that rotatablely moves, α
bBe the electrode angle, α
aBe the insulation angle α between every group of adjacent electrode
dBe every pair of insulation angle between two groups of adjacent electrodes, α
tBe two pairs of insulation angles between electrode group adjacent electrode, α
d=α
a+ α
b=α
T, α
t=α
T/ 4.
Fig. 9 increment type capacitance encoder of the present invention testing circuit.R among the figure
1, R
2, R
3, R
4Be equivalent same resistance, an end of these four resistance is connected to potentiometer W respectively
1And W
2An end, the other end of four resistance respectively with Fig. 5 movable plate electrode (or Fig. 8 fixed plate) top electrode draw outward the end a
1, b
1, a
2, b
2W be connected together altogether with being connected to electronic switch d end and phase inverter (gate circuit) input end
1And W
2Be the leveling potentiometer, tap terminals is connected to by resistance R in the middle of it
5With R
6, capacitor C
1The master who forms with phase inverter makes oscillator output supply with electronic switch controling end e through its anti-phase output MG end of shaping output MG end (or being connected on power positive end) of phase inverter, and electronic switch c end is gone up s end common ground (or body contact) with Fig. 4 fixed plate (or Fig. 7 movable plate electrode).Make oscillator, electronic switch and phase inverter (gate circuit) form periodically charging and discharge by main, the capacitance change of capacitive transducer is converted to the pulse width variation amount.When the master makes oscillator output MG=1, by potentiometer W
1And W
2Through resistance R
1, R
2, R
3And R
4Respectively to capacitor C
A1, C
B1, C
A2And C
B2Charging, at this moment, MG=0, electronic switch disconnects a
1, b
1, a
2And b
2Ground loop, when MG=0, stop charging, simultaneously the MG=1 electric switch that closes makes c end and d termination logical, a
1, b
1, a
2And b
2End is connected ground end (s end), C respectively
A1, C
B1, C
A2And C
B2Discharge over the ground.This periodically charges and discharges, with two pairs of differential change capacitor C
A1, C
B1And C
A2, C
B2Be converted to the pulse width amount A of two pairs of differential change
1, B
1And A
2, B
2, through anti-phase be A
1, B
1And A
2With B
2Be combined as A
1With B
1, A
1With B
1And A
2With B
2, A
2With B
2, after comparing by the Sheffer stroke gate (perhaps fellow disciple or rejection gate) of two double input ends respectively, the corresponding Y that is output as
A1, Y
B1And Y
A2, Y
B2, the output of corresponding Sheffer stroke gate
With
With this relatively the R-S trigger formed of back output trigger action Sheffer stroke gate (or the R-S trigger of forming with the double input end rejection gate as shown in figure 10) select for use the Q end of these two R-S triggers to export to be respectively PHI0 and PHI90.90 ° of the phase phasic differences of these two square-wave output signals, it is T/4 (the T cycle), because 90 ° of two square-wave output signal phases phasic differences, by detecting the leading of these two square-wave output signal phase places or lagging behind, just can determine the sense of displacement of increment type capacitance encoder, simultaneously also for add/down counter provides the count pulse relevant with speed.The phase place of two square-wave output signals is leading or lag behind, and removes outside the Pass sense of displacement with the increment type capacitance encoder has, and depends on that also when making, two pairs of differential capacitors change the outer line termination a that draws of electrodes
1, b
1And a
2, b
2Demarcation, form R-S and touch that to return device be the Sheffer stroke gate of double input end, still the rejection gate of double input end and PHI0 and PHI90 take the R-S trigger the Q end still Q hold etc.
Circuit of the present invention and photoelectric encoder circuit work Zhang Yulong Zhu Xiyi yellow ginger such as are controlled such as [day] Ji Yexin to overstaff and translates the sensor circuit designs handbook, 185 pages of optical encoder circuit diagrams 2 in China Measuring Press's book Dec one in 1989, under the identical performance parameter of the present invention with photoelectric encoder, circuit component of the present invention is few, the element price is low, element CMOSization, be easy to integrated, be suitable for button cell to be powered for a long time, do not have dead electricity or have a power failure after the radix difficulty seek and from the problems such as interference of power end, the temperature range of cmos element, voltage range and aspect such as anti-interference also are better than the used TTL element of photoelectric encoder; In addition, the present invention is simple in structure, need not light prober and the shared space and the trouble of Installation and Debugging of light source.
Figure 10 is Fig. 9 testing circuit of the present invention, selects for use doubinary system 4 to select 1 code translator/separation vessel 4555 (or 4556) element to replace part 4069 and 4011 elements among Fig. 9, and exports Y with 4555 elements
1=AB and Y
2=AB triggers by the double input end rejection gate and forms the R-S trigger that the R-S triggering is made up of the double input end Sheffer stroke gate; If with 4556, then export Y with it
1=AB and Y
2=AB triggers the R-S trigger of being made up of the dual input Sheffer stroke gate.Four single-ended in-gate circuits (phase inverter) of this circuit 4555 (or 4556) element input end also can save.
Figure 11 is that Fig. 9 testing circuit of the present invention is selected programmable logic device (PLD) (PLD) for use, and part 4069 and 4011 elements gives an example in replacement Fig. 9 testing circuit.This figure takes out angular encoder for described first kind corresponding to 202-209 page or leaf in Zhu's generation letter programmable logic device (PLD) PLD practical design the 1st edition book in technology Electronic Industry Press January in 1994, and with PAL16R4 element used in the book, use element instead, its objective is A among Fig. 9 for PAL16R6
1, B
1, A
2, B
2PHI0 and PHI90 output circuit that phase inverter behind four ends and double input end Sheffer stroke gate are formed, also incorporate in the PAL16R6 element, PHI0 among Figure 11 and PHI90 are corresponding to the R-S trigger output terminal Q among Fig. 9, by described in the above-mentioned book, write corresponding design document.Also the master among clock CLK oscillating impulse source and Fig. 9 can be made oscillation source integrate with in the PAL element, or a public external oscillation source carry out frequency division by the PAL element.This example explanation fundamental mode circuit of the present invention if make the wide special-purpose CMOS chip of versatility, only needs more than 100 MOS etc., all the other available PAL element or single chip microcomputer chips.
Circuit such as the sensor circuit designs handbook book of work of A output control etc. differential amplifier circuit, pulse switching circuit and the output circuit of 185 pages of Fig. 2 in to(for) aforementioned [day] Ji Yexin and B output are impossible incorporate in the PAL element.
Figure 12 is a block diagram of forming the basic link of Fig. 9 pair of electrodes group testing circuit of the present invention.G is the main oscillator that makes.C-T is the pulse width amount that the differential change electric capacity of capacitive transducer is converted to differential change, and T-T is the pulse inversion device, and COMP is that pulse width compares, and RS-FF is the R-S trigger.Electronic detection circuit and the element of realizing these basic links are a lot, except that Fig. 9, Figure 10 and Figure 11, the differential change electric capacity of capacitive transducer is converted to the translation circuit of the wide variable of pulse of differential change, voltage available comparer and constant current source, also available pair monostalbe trigger (as elements such as 4528,4538 and 4098) pulse width relatively also available with door, rejection gate and other composite door elements etc., R-S trigger also available 4043 or elements such as 4044.Fig. 9 circuit is economical simple, and used element only needs 3-5 yuan.
Giving an example of the combined type annular fixed plate of the incremental transducer that Figure 13 the present invention rotatablely moves.It is on the fixed plate of two pairs of four groups of electrodes of a cover of Fig. 8, adds identical two pairs of four groups of electrode groups of a cover, and the electrode width of these two covers is identical, and electrode number is identical, and interelectrode insulation width is also corresponding identical.First group of first electrode of second cover and first group of first interelectrode n α that is spaced apart of first cover
T/ 8 (n is an integer), the pairing movable plate electrode of this combined type annular fixed plate is identical with Fig. 7 annular movable plate electrode, testing circuit makes the oscillator except that shared master, add the identical testing circuit of a cover, promptly in Fig. 9 testing circuit, except that main make oscillator be public, add the identical testing circuit of a cover, the identical testing circuit of two covers is subjected to the master to make oscillator control jointly, after the cover that adds detect electricity and be output as PHI45 and the PhI135 square wave of phasic difference T/4 mutually, and PHI45 master PHI0 phase differential T/8, the output of two covers, four lines is respectively PHI0, PHI45, PHI90 and PHI135, count pulse doubles.This combination is simpler than the combination of photoelectric encoder, and the bearing accuracy of compound electrode guarantees by printed wiring board technology, and simple and reliable.Do not exist in the photoelectric encoder and lay space and the difficult shortcoming that can guarantee of bearing accuracy because of photovalve.Combination of the present invention is very convenient, the combination tricks can increase, as the movable plate electrode of motion is clipped between two fixed plates, the outer line end that draws of movable plate electrode only needs ground connection (or body contact), not having other lead-in wire, need not to use brush, is the fixed plate of combination in the both sides of movable plate electrode, combination fixed plate electrode doubles like this, and this array mode is impossible to photoelectric encoder.
All there is the sectional structure synoptic diagram of deciding plate Figure 14 increment type capacitance encoder of the present invention sensor movable plate electrode both sides.5 and 7 is fixed plates of movable plate electrode 6 both sides among the figure, the electrode 9 and 8 of movable plate electrode 6 and fixed plate 7 correspondences, the electrode 10 and 11 of movable plate electrode 6 and fixed plate 5 correspondences, the 12nd, the rotation axis that movable plate electrode 6 rotatablely moves, movable plate electrode 6 is identical with the spacing of its both sides fixed plate 5 and 7, the two sides top electrode 9 of movable plate electrode 6 and 10 electrode width, electrode number equates with identical with electrode pattern, and correspondence is overlapping with one heart; Double-sided electrode 10 and 9 figure are concentric on the figure of fixed plate 5 and 7 top electrodes 11 and 8 and the movable plate electrode.These 2 requirements, existing printed circuit board technology is simple and easy to do.Movable plate electrode is salable between two fixed plates, does not influence the movable plate electrode motion, and this is to guaranteeing not to be subjected to the good measure of such environmental effects.
Figure 15 absolute type capacitance encoder of the present invention testing circuit.C among the figure
11And C
12Be a pair of " bigness scale " differential change electric capacity, C
21And C
22Be a pair of " essence is taken aim at " differential change electric capacity, the absolute position point is selected in C
11=C
12And C
21=C
222 points, " essence is taken aim at " precision height measures regional little; " bigness scale " precision is low, measuring range is wide, " bigness scale " relatively waits the testing circuit (Fig. 9) of link and above-mentioned increment type capacitance encoder identical with pulse width amount, pulse width anti-phase and two differential change that the master of " essence is taken aim at " testing circuit makes oscillator, pair of differential variation electric capacity convert the pair of differential variation to, or similar, Y among Figure 15
11, Y
12And Y
21, Y
22Output be not that image pattern 9 circuit trigger the R-S trigger like that, but trigger monostalbe trigger respectively, among Figure 15 by rejection gate, the capacitor C of double input end
2(or C
3Or C
4Or C
5), resistance R
7(or R
8Or R
9Or R
10) and phase inverter composition monostalbe trigger, at C
11=C
12And C
21=C
22The time, four monostable output Q
11, Q
12And Q
21, Q
22Be all electronegative potential (zero potential), again the output Q that forms by rejection gate and phase inverter
ABe noble potential, what it showed is the output signal of the aiming anchor point of absolute position point.When not aimed at, Q
ABe electronegative potential (zero potential).The electrode group of two pairs of differential change is merged into the electrode group that pair of differential changes, i.e. C
10=C
11+ C
21And C
20=C
12+ C
22, the testing circuit of two pairs of electrode groups of its " bigness scale " and " essence is taken aim at " subtracts and is pair of electrodes group testing circuit, and circuit component reduces half.If " bigness scale " electrode width and " essence is taken aim at " when electrode width differs greatly, can increase several differential change electrode groups that electrode width is not waited, the electrode width of minimizing adjacent electrode group poor, i.e. b
1s＞b
2s＞...＞b
NsC
10=C
11+ C
21+ ... + C
N1And C
20=C
12+ C
22+ ... + C
N2(n is a positive integer) when avoiding electrode width to differ greatly, multiple spot aiming anchor point occurs.
Applicating example of the present invention.
In straight-line increment type capacitance encoder Fig. 4, select a
s=b
s=0.40mm, a
d=a
s+ b
s=0.80mm, a
t=T
s/ 4=0.20mm, every group of number of electrodes is 16, and each electroplax length is 30mm, and distance (d) is 0.20mm between fixed plate and the movable plate electrode; Selecting Figure 11 for use is testing circuit, R=R
1=R
2=R
3=R
4=200k, W
1=W
2=100k, each pitch T
s=a
s+ b
sIn=the 0.80mm, 8 output signals are arranged, the resolution of each signal is 0.10mm, makes in the debugging, and above-mentioned d and R parameter according to the requirement of actual measurement and frequency response (the main oscillation frequency that makes), are suitably adjusted.
At present, be distinguished as the straight line of 0.10mm or the numeral of swing offset measuring system on the market and show product, still belong to short-supply goods, as steel tape, steel ruler or the like product still is the scale indication, and this example can be made the most of the advantage to this renewal.
Claims (6)
1. capacitance encoder is made up of physical construction, sensor and testing circuit, and physical construction has pedestal and slide etc.; Sensor has the fixed plate and the movable plate electrode of opposing parallel motion, it is characterized in that the electrode on straight-line increment type capacitance encoder fixed plate is wide and equidistant the arrangement, two pairs of electrode groups are arranged on the movable plate electrode, every pair of electrode group has two arrays of electrodes, two pairs of four groups of electrodes that the total electrode number of electrode group equates, the width of every group of electrode is identical wide and equidistant the arrangement with arrangement and fixed plate top electrode, the arrangement of every pair of two arrays of electrodes is regularly arranged by the difference changeization, and insulation width was T between two pairs of electrode groups were adjacent
s/ 4 (T
s=a
s+ b
s, b
sElectrode width, a
sInsulation width between adjacent electrode), so-called movable plate electrode the and decide utmost point and be meant relative motion, both are fixing interchangeable with mode of motion.The fixed plate and the movable plate electrode of the increment type capacitance encoder that rotatablely moves are annulars, it is represented with angle respectively corresponding to the fixed plate of straight-line increment type capacitance encoder and the electrode width and the insulation width of movable plate electrode, this straight line is corresponding identical with two kinds of pole plate electrode spread rules that rotatablely move, two kinds of testing circuits are also identical, testing circuit is the circuit that detects every pair of two arrays of electrodes group electric capacity differential change respectively, the testing circuit of two pairs of electrode groups is identical, the circuit of every pair of two arrays of electrodes group electric capacity differential change, control by the main oscillator that makes, a pair of identical electronic switch, resistance and single-ended in-gate circuit (phase inverter) are formed charging and discharge circuit periodically, pair of differential is changed electric capacity convert the pulse width amount that pair of differential changes to, through anti-phase, get a positive pulse and another rp pulse respectively and form two groups, gate circuit by two double input ends compares, draw two differences, trigger the R and the S end of R-S trigger respectively, the output of R-S trigger is a square wave, another is to electrode group and testing circuit same as described above, and its R-S trigger is also exported the identical square wave that differs T/4 (T square-wave cycle) with above-mentioned square wave phase.The absolute type capacitance encoder, the electrode of sensor is regularly arranged by differential change, divide two pairs of electrode groups of " bigness scale " and " essence is taken aim at " and corresponding " bigness scale " testing circuit identical with " essence is taken aim at " are arranged, the master of this testing circuit makes oscillator, the differential variable quantity of electric capacity is converted to the pulse width amount, pulse widths anti-phase and two differential change relatively wait link, identical with the testing circuit of above-mentioned increment type capacitance encoder, and the residual quantity of pulse width after relatively, be to trigger monostable circuit separately in the absolute type capacitance encoder, when four monostalbe trigger outputs of " bigness scale " and " essence is taken aim at " are all zero, conversion output through gate circuit is noble potential again, and this is the output signal of the aiming anchor point of absolute position point.
2. press the capacitance encoder of claim 1 defined, it is characterized in that pair of electrodes group testing circuit has the main oscillator that makes, the differential change electric capacity of capacitive transducer is converted to the translation circuit of the pulse width amount of differential change, phase inverter, basic ring such as pulse width comparator circuit and R-S device, electronic detection circuit and the element of realizing these basic links are a lot, the differential change electric capacity of capacitive transducer is converted to the translation circuit of the pulse width amount of differential change, voltage available comparer and constant current source, also available pair monostalbe trigger is (as 4528, elements such as 4538 and 4098), pulse width more available and door or rejection gate and other composite door circuit etc., the R-S trigger can be with elements such as 4043 or 4044, and also available programmable logic device (PLD) PLD simplifies the fundamental mode circuit.
3. by the capacitance encoder of claim 1 and 2 defineds, it is characterized in that selecting for use doubinary system 4 to select 1 code translator/separation vessel 4555 or 4556 elements, replace part phase inverter and both-end in-gate circuit in the testing circuit, reduce the universal component quantity in the testing circuit.
4. by the capacitance encoder of claim 1 and 2 defineds, it is characterized in that selecting for use programmable logic device (PLD) PLD element, replace part phase inverter and both-end in-gate circuit in the testing circuit, reduce the universal component quantity of testing circuit.
5. press the capacitance encoder of claim 1 defined, it is characterized in that two pairs of four groups of electrode groups of the cover of one on the sensor fixed plate, amplification is identical two pairs of four groups of electrodes of two covers, its pairing movable plate electrode is constant, what increase is identical with original electrode width, electrode number is identical, and interelectrode insulation width is also corresponding identical, first group of first electrode of second cover and first group of first interelectrode n α that is spaced apart of first cover
T/ 8 (n is an integer), testing circuit makes the oscillator except that shared master, adds the identical testing circuit of a cover, and two cover testing circuits are identical, and with being subjected to main order vibration control, output count pulse number doubles.Also can be clipped in two to movable plate electrode and decide to have increased fixed plate between the utmost point, the tricks of amplification compound electrode group increases the output count pulse.
6. by the absolute type capacitance encoder of claim 1 defined, when it is characterized in that,, merge into the electrode group that pair of differential changes, i.e. C the electrode group of two pairs of differential change the combination in parallel of " bigness scale " and " essence is taken aim at " two pairs of electrode groups
10=C
11+ C
21And C
20=C
12+ C
22The testing circuit of two pairs of electrode groups of corresponding " bigness scale " and " essence is taken aim at " subtracts and is pair of electrodes group testing circuit, if " bigness scale " electrode width and " essence is taken aim at " are when electrode width differs greatly, can increase several differential change electrode groups that electrode width is not waited, reduce electrode width poor of adjacent electrode group, i.e. b
1s＞b
2s＞...＞bns; c
10=c
11+ c
21+ ... + c
N1And c
20=c
12+ c
22+ ... + c
N2Multiple spot aiming anchor point appears in (n is a positive integer) when avoiding electrode width to differ greatly.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98115362 CN1100251C (en) | 1998-06-30 | 1998-06-30 | Capacitance encoder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98115362 CN1100251C (en) | 1998-06-30 | 1998-06-30 | Capacitance encoder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1240928A true CN1240928A (en) | 2000-01-12 |
| CN1100251C CN1100251C (en) | 2003-01-29 |
Family
ID=5224537
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 98115362 Expired - Fee Related CN1100251C (en) | 1998-06-30 | 1998-06-30 | Capacitance encoder |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1100251C (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100371673C (en) * | 2003-10-31 | 2008-02-27 | 中国科学院物理研究所 | Stepping motor for scanning tunnel microscope |
| CN100392356C (en) * | 2001-04-23 | 2008-06-04 | 利倍库斯株式会社 | Position sensor |
| CN100460821C (en) * | 2007-06-16 | 2009-02-11 | 昝昕武 | Engine throttle position sensing method and sensor |
| CN101988837A (en) * | 2009-08-07 | 2011-03-23 | 鸿富锦精密工业（深圳）有限公司 | Rotation sensing device and portable electronic device with rotation sensing device |
| CN103162606A (en) * | 2012-11-30 | 2013-06-19 | 陈晓玉 | Capacitive non-contact position sensor |
| CN103868442A (en) * | 2012-12-12 | 2014-06-18 | 王祖斌 | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| CN105157732A (en) * | 2015-07-14 | 2015-12-16 | 程有信 | Multi-connected and multi-sector differential capacitance sensor system device |
| CN106052593A (en) * | 2015-04-03 | 2016-10-26 | 株式会社三丰 | Phase adjuster and encoder |
| TWI588450B (en) * | 2015-04-21 | 2017-06-21 | Murata Manufacturing Co | Encoder |
| CN109373884A (en) * | 2018-11-09 | 2019-02-22 | 深圳市百兴源科技有限公司 | A kind of throttle stroke measuring device |
-
1998
- 1998-06-30 CN CN 98115362 patent/CN1100251C/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100392356C (en) * | 2001-04-23 | 2008-06-04 | 利倍库斯株式会社 | Position sensor |
| CN100371673C (en) * | 2003-10-31 | 2008-02-27 | 中国科学院物理研究所 | Stepping motor for scanning tunnel microscope |
| CN100460821C (en) * | 2007-06-16 | 2009-02-11 | 昝昕武 | Engine throttle position sensing method and sensor |
| CN101988837A (en) * | 2009-08-07 | 2011-03-23 | 鸿富锦精密工业（深圳）有限公司 | Rotation sensing device and portable electronic device with rotation sensing device |
| CN103162606A (en) * | 2012-11-30 | 2013-06-19 | 陈晓玉 | Capacitive non-contact position sensor |
| WO2014089892A1 (en) * | 2012-12-12 | 2014-06-19 | Wang Zubin | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| CN103868442A (en) * | 2012-12-12 | 2014-06-18 | 王祖斌 | Differential capacitance displacement conversion and subdivision method and capacitive linear displacement measuring system |
| CN103868442B (en) * | 2012-12-12 | 2019-03-29 | 王祖斌 | The conversion of differential capacitance displacement and divided method and capacitive linear displacement measuring system |
| CN106052593A (en) * | 2015-04-03 | 2016-10-26 | 株式会社三丰 | Phase adjuster and encoder |
| CN106052593B (en) * | 2015-04-03 | 2020-05-01 | 株式会社三丰 | Phase adjuster and encoder |
| TWI588450B (en) * | 2015-04-21 | 2017-06-21 | Murata Manufacturing Co | Encoder |
| CN105157732A (en) * | 2015-07-14 | 2015-12-16 | 程有信 | Multi-connected and multi-sector differential capacitance sensor system device |
| CN109373884A (en) * | 2018-11-09 | 2019-02-22 | 深圳市百兴源科技有限公司 | A kind of throttle stroke measuring device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1100251C (en) | 2003-01-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1100251C (en) | Capacitance encoder | |
| US20020135384A1 (en) | Capacitive displacement sensor | |
| US5534859A (en) | Instrument for measuring lengths or angles | |
| US5929631A (en) | Method of position sensing utilizing giant magneto resistance elements and solid state switch array | |
| US6366078B1 (en) | Inductive angle sensor with a plurality of receiving coils and an evaluation circuit | |
| KR20110089866A (en) | Position detector | |
| DE3711062A1 (en) | Capacitive absolute position measurement device | |
| CN101408409B (en) | High precision digital type linear displacement transducer | |
| US3729728A (en) | Capacitive switching device | |
| CN109341517A (en) | A kind of absolute type capacitive grating displacement rotating encoder | |
| WO1992001942A1 (en) | Shaft rotation analyzer using constant voltage variable capacitance transducer | |
| CN1140260A (en) | Method and apparatus for measuring change in capacitance values in dual capacitors | |
| CN86106558A (en) | Grid displacement sensor of capacity type | |
| CN1086309A (en) | The measurement mechanism that is used for Absolute position measurement | |
| JP3171998B2 (en) | Absolute value measurement scale device | |
| CN1928899A (en) | Mechanical counter for electromagnetic induction coding | |
| US5783817A (en) | Device for detecting a position of an object moving in rotation or translation relative to a base | |
| JPS60102518A (en) | Digital measuring device | |
| CN213902232U (en) | Hydraulic cylinder displacement detection device based on programmable linear Hall | |
| CN105043618B (en) | A kind of electric capacity torque sensor | |
| CN111397498A (en) | Absolute time grating linear displacement sensor | |
| Fabian et al. | A measurement algorithm for capacitive speed encoder with a modified front-end topology | |
| CN210051289U (en) | Electromagnetic displacement measuring circuit | |
| SU1626081A1 (en) | Capacitive pickup of linear movement | |
| CN208887657U (en) | A kind of photoelectric encoder using MN chip |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |