CN102780481B - Non-contact analog signal transmission device between moving parts - Google Patents
Non-contact analog signal transmission device between moving parts Download PDFInfo
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- CN102780481B CN102780481B CN201210245520.XA CN201210245520A CN102780481B CN 102780481 B CN102780481 B CN 102780481B CN 201210245520 A CN201210245520 A CN 201210245520A CN 102780481 B CN102780481 B CN 102780481B
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Abstract
The invention discloses a non-contact analog signal transmission device between moving parts, which is mainly used for solving the problems of distortion of transmission analog signals and poor anti-interference ability of the existing device. The non-contact analog signal transmission device comprises a Sigma-delta modulator (101), two groups of coupling capacitors (102A, 102B), two groups of integrators (103A, 103B), a subtracter (104), a controllable gain amplifier (105), two comparators (106, 107), an RS (remote sensing) trigger (108) and a demodulator (109), wherein the Sigma-delta modulator is used for modulating an input signal f0, outputting two lines of differential data streams and respectively inputting into the two groups of coupling capacitors for coupling, the two groups of the integrators, the subtracter and the controllable gain amplifier constitute a differential charge amplifier for performing extraction and amplification on the data streams, the data streams after amplification pass through the two comparators, two lines of square wave pulses are output to the RS trigger, the RS trigger outputs a final data stream under the triggering of the two lines of square wave pulses, and the demodulator is used for demodulating the data stream and outputting an analog signal f1 which is consistent with the f0. The non-contact analog signal transmission device disclosed by the invention has the advantages of simple structure, stable performance and high signal transmission precision.
Description
Technical field
The invention belongs to communication technical field, relate to the device of the noncontact analog signal transmission between moving component, can between moving component, carry out noncontact analog signal transmission.
Background technology
Transfer of data between parts mainly comprises that Energy Transfer, analog quantity transmission and digital quantity transmit three classes, if can realize the non-contact transmission of this three classes signal between parts, parts just can be realized Entirely contactless work, avoid the frictional dissipation of parts, make equipment work safer, increase the working life of equipment simultaneously.
About noncontact Energy Transfer problem, Chinese patent application " resonant tracking contactless power supply device and method of supplying power to " (publication number: 101834473A) has proposed electric supply installation and method, solve transmitting non-contact electric energy problem, make wireless power transmission become possibility, on high-power Energy Transfer, obtained breakthrough.
The existing mode for the transmission of noncontact digital quantity is mainly transmitted two kinds of technological means as main taking wireless radio frequency transmission and light, has obtained a large amount of achievements and has had commercial product to come out.
The existing method for non-contact structure analog signal transmission mainly contains two kinds, and one is by slip ring structure, and this structure does not realize real non-contact transmission; Another kind is to complete the quantised samples to analog signal by microprocessor and AD, is converted into digital data transmission, after through DA outputting analog signal, this device can be realized the non-contact transmission of analog signal, but still has a following defect:
1, use microprocessor, during in the face of complex electromagnetic environment, easily caused the problem of deadlock, caused error of transmission or interruption, poor reliability, and also cost is high;
2, use DA outputting analog signal, output waveform has ladder, is not level and smooth analog signal, causes the distortion of analog signal.
Summary of the invention
The object of the invention is to the deficiency for existing apparatus, the noncontact analog signal transmission device between the moving component that propose a kind of simple in structure, stable performance, is easy to realize, improves the precision of analog signal transmission.
For achieving the above object, noncontact analog signal transmission device between moving component of the present invention, is characterized in that comprising: Sigma-delta modulator, two groups of noncontact coupling capacitances, two groups of integrators, subtracter, controllable gain amplifier, two comparators, demodulator and rest-set flip-flops;
Described Sigma-delta modulator, for the analog signal f to input
0modulate the data flow I of output two-pass DINSAR
1, I
2, first via data flow I
1through first group of coupling capacitance, output coupled signal is input to the positive input terminal of subtracter after by first group of integrator integral operation; The second circuit-switched data stream I
2through second group of coupling capacitance, output coupled signal is input to the negative input end of subtracter after by second group of integrator integral operation;
Described subtracter, for completing the additive operation to two paths of differential signals, output difference value signal is to controllable gain amplifier, and controllable gain amplifier is input to forward comparator and negative sense comparator after this difference signal is adjusted simultaneously;
Described forward comparator, for by the positive threshold voltage U of the forward single pulse signal of subtracter output signal and setting
1compare, by 0 to 1 jumping moment, export a square-wave pulse to rest-set flip-flop, wherein U at input signal
1value be no more than the difference signal of subtracter output forward peak value 1/2nd;
Described negative sense comparator, for by the negative threshold voltage U of the negative sense single pulse signal of subtracter output signal and setting
2compare, by 1 to 0 jumping moment, export a square-wave pulse to rest-set flip-flop, wherein U at input signal
2=-U
1;
Described rest-set flip-flop, under the triggering for the square-wave pulse signal in above-mentioned two comparators output, produces and first via data flow I
1consistent data flow I
8be input to demodulator;
Described demodulator, for by data flow I
8be demodulated to and the analog signal f inputting from Sigma-delta modulator
0consistent analog signal f
1.
Noncontact analog signal transmission device between above-mentioned moving component, is characterized in that described Sigma-delta modulator comprises: a comparator, a d type flip flop, an oscillator, a subtracter and an integrator; The positive input terminal input analog signal f of comparator
0, output output sampled signal I
0, this sampled signal is quantified as two-pass DINSAR data flow I by d type flip flop
1and I
2, output to respectively two groups of coupling capacitances, simultaneously first via data flow I
1be input to subtracter and reference voltage U
0after=2.5V subtracts each other, the difference signal of output completes D/A by integrator and transforms, the analog signal f of output
2feed back to the negative input end of comparator, oscillator output signal is input to the input end of clock of d type flip flop again.
Noncontact analog signal transmission device between above-mentioned moving component, it is characterized in that two groups of described noncontact coupling capacitances form by two capacitor plates, and two moving component A, B mounted externally are upper, first group of noncontact coupling capacitance is by two capacitor plate H
1and H
3form two capacitor plate H
1and H
3in components A and part B mounted externally, horizontally slip along parts respectively; Second group of noncontact coupling capacitance is by two capacitor plate H
2and H
4form two capacitor plate H
2and H
4in components A and part B mounted externally, horizontally slip along parts respectively.
Noncontact analog signal transmission device between above-mentioned moving component, is characterized in that described subtracter is by an operational amplifier V
1with four resistance R
1, R
2, R
3, R
4composition, data flow I
1by the 3rd resistance R
3be input to operational amplifier V
1positive input terminal, the 4th resistance R
4one termination operational amplifier V
1positive input terminal, other end ground connection, reference voltage U
0=2.5V is by the first resistance R
1be input to operational amplifier V
1negative input end, at operational amplifier V
1output by the second resistance R
2feed back to operational amplifier V
1negative input end, wherein four resistor satisfied relational expressions:
The present invention, has the following advantages for compared with non-contact data transmitting device with existing:
1, the present invention is owing to only having used comparator, operational amplifier, d type flip flop and a small amount of resistance capacitance, and circuit structure is simple, with low cost;
2, the present invention is owing to using demodulator and modulator settling signal to transform, thereby do not use microprocessor, and working stability, can tackle complicated electromagnetic environment;
3, the present invention is owing to carrying out demodulation in rear class output with low pass filter, therefore outputting analog signal precision is high.Below in conjunction with accompanying drawing, the invention will be further described:
Brief description of the drawings
Fig. 1 is the overall structure figure of apparatus of the present invention;
Fig. 2 is the Sigma-delta modulator circuit schematic diagram in the present invention;
Fig. 3 is two groups of noncontact coupling capacitance structural representations in the present invention;
Fig. 4 is the installation site schematic diagram of two groups of noncontact coupling capacitances in the embodiment of the present invention.
Embodiment
With reference to Fig. 1, noncontact analog signal transmission device between moving component of the present invention, comprises Sigma-delta modulator 101, two groups of noncontact coupling capacitance 102A and 102B, two groups of integrator 103A and 103B, subtracter 104, controllable gain amplifier 105, two comparators 106 and 107, rest-set flip-flop 108 and demodulators 109.This Sigma-delta modulator 101 is for the analog signal f to input
0modulate output two-pass DINSAR data flow I
1and I
2; These two groups of noncontact coupling capacitance 102A and 102B are used for two-pass DINSAR data flow I
1and I
2non-contact transmission, wherein first via data flow I
1by exporting Third Road data flow I after first group of coupling capacitance 102A
3, the second circuit-switched data stream I
2by exporting the 4th circuit-switched data stream I after second group of coupling capacitance 102B
4; These two groups of integrator 103A and 103B, subtracter 104 and the common composition differential charge of controllable gain amplifier 105 amplifier, for extracting and amplifying two paths of data stream I
3and I
4; This forward comparator 106 is for by controllable gain amplifier 105 output signal I
5in forward single pulse signal and the positive threshold voltage U of setting
1compare, at input signal I
5by 0 to 1 jumping moment, export a square-wave pulse to rest-set flip-flop 108, negative sense comparator 107 is for by controllable gain amplifier 105 output signal I
5in negative sense single pulse signal and the negative threshold voltage U of setting
2compare, at input signal I
5by 1 to 0 jumping moment, export a square-wave pulse to rest-set flip-flop 108; Under the triggering of rest-set flip-flop 108 for the square-wave pulse signal in above-mentioned two comparators output, produce and first via data flow I
1consistent data flow I
8be input to demodulator 109, demodulator 109 is for by data flow I
8be demodulated to and the analog signal f inputting from Sigma-delta modulator 101
0consistent analog signal f
1.
In this embodiment, during with the work of thermocouple measurement drill for oil well, the temperature of drill bit, utilizes the noncontact analog signal transmission device between moving component of the present invention that measurement result is transferred to external display device.Whole device is divided into data transmitting portion and data receiver part, and the inside that data transmitting portion is arranged on drill bit is connected with thermocouple temperature measurement system, on data receiver part pedestal mounted externally, is connected with display device.
Be arranged on the thermocouple of drill bit internal, measure the temperature of drill bit, and the temperature data of measurement is transferred to data transmitting portion.
Data transmitting portion comprises Sigma-delta modulator 101, as shown in Figure 2, it is made up of a comparator 201, d type flip flop 202, oscillator 203, a subtracter 204 and an integrator 205, and wherein, subtracter 204 is by an operational amplifier V
1with four resistance R
1, R
2, R
3, R
4composition, four resistance R
1, R
2, R
3, R
4meet following relational expression:
Integrator 205 is by a resistance R
5with a capacitor C
1composition; The temperature T of thermocouple measurement drill bit, temperature data is input to the positive input terminal of comparator 201, comparator output sampled signal T
0be input to d type flip flop 202, the output signal of oscillator 203 is input to the input end of clock of d type flip flop 202, and the frequency of oscillator 203 is got f=500kHz herein, and the input clock of d type flip flop 202 is 500kHz; D type flip flop 202 is by sampled signal T
0be quantified as two-pass DINSAR data flow I
1and I
2, wherein first via data flow I
1output to first group of coupling capacitance 102A, the second circuit-switched data stream I
2output to second group of coupling capacitance 102B; Meanwhile, first via data flow I
1by the 3rd resistance R
3be input to operational amplifier V
1positive input terminal, the 4th resistance R
4one termination operational amplifier V
1positive input terminal, other end ground connection; Reference voltage U
0=2.5V is by the first resistance R
1be input to operational amplifier V
1negative input end, at operational amplifier V
1output by the second resistance R
2feed back to operational amplifier V
1negative input end; Operational amplifier V
1output by the 5th resistance R
5receive capacitor C
1upper, capacitor C
1one end ground connection in addition; From the 5th resistance R
5with capacitor C
1node on draw temperature signal f
2feed back to operational amplifier V
1negative input end.
Two groups of noncontact coupling capacitance 102A and 102B form by two capacitor plates, and as shown in Figure 3, wherein first group of noncontact coupling capacitance 102A is by two capacitor plate H for its structure chart
1and H
3form, second group of noncontact coupling capacitance 102B is by two capacitor plate H
2and H
4form, as shown in Figure 4, wherein Fig. 4 (a) is the overall schematic of drill bit and pedestal in the installation site of these two noncontact coupling capacitances, and drill bit is arranged on the inside of pedestal, and drill bit can rotate around pedestal; Fig. 4 (b) is capacitor plate H
1with capacitor plate H
2installation site figure on drill bit, capacitor plate H
1with capacitor plate H
2be the electric conductor of ring-type, be fixed on the outer surface of drill bit, capacitor plate H
1be connected with shielding conductor with the output Q of Sigma-delta modulator 101, capacitor plate H
2output with Sigma-delta modulator 101
connected with shielding conductor; Fig. 4 (c) is capacitor plate H
3with capacitor plate H
4installation site figure on pedestal, capacitor plate H
3with capacitor plate H
4be the electric conductor of ring-type, be fixed on the inner surface of pedestal, capacitor plate H
3be connected with shielding conductor with first group of integrator 103A, capacitor plate H
4be connected with shielding conductor with second group of integrator 103B.
Data reception portion is divided and is comprised two groups of integrator 103A and 103B, subtracter 104, controllable gain amplifier 105, two groups of comparators 106 and 107, rest-set flip-flop 108 and demodulators 109.By the Third Road differential data stream I of first group of coupling capacitance 102A coupling
3after first group of integrator 103A, be input to the positive input terminal of subtracter 104, by second group of coupling capacitance 102B coupling, tetra-road differential data stream I
4after second group of integrator 103B, be input to the negative input end of subtracter 104; Subtracter 104 output difference divided data stream I
5to controllable gain amplifier 105, to differential data stream I
5amplify output two paths of signals I after amplifying
6and I
7, wherein I
6be input to forward comparator 106, with the positive threshold voltage U setting
1=1V compares, at I
6by 0 to 1 jumping moment, export a square-wave pulse h
1to the input R of rest-set flip-flop 108; I
7be input to negative sense comparator 107, with the negative threshold voltage U setting
2=-1V compares, at I
7by 1 to 0 jumping moment, export a square-wave pulse h
2to the input S of rest-set flip-flop 108; Rest-set flip-flop is at described square-wave pulse signal h
1and h
2triggering under, produce with first via data flow I
1consistent data flow I
8be input to demodulator 109; Demodulator 109 is by data flow I
8be demodulated to and the analog signal f inputting from Sigma-delta modulator 101
0consistent analog signal f
1.
The analog signal f exporting from demodulator 109
1be the temperature T of thermocouple measurement, utilize the data transmitting portion of this device that temperature T is sent to the data receiver part being arranged on pedestal from drill bit internal, pedestal data receiver part is connected with external display device, temperature data is input to display device, realizes the real-time monitoring of temperature of diamond bit.
Above embodiment does not form any restriction to content of the present invention to of the present invention with reference to explanation, obviously, under thought of the present invention, can make multi-form structure modify, but these are all at the row of protection of the present invention.
Claims (6)
1. the noncontact analog signal transmission device between a moving component, it is characterized in that comprising: Sigma-delta modulator (101), two groups of noncontact coupling capacitances (102A, 102B), two groups of integrators (103A, 103B), subtracter (104), controllable gain amplifier (105), two comparators (106,107), demodulator (109) and rest-set flip-flop (108), two comparators (106,107) comprise forward comparator (106) and negative sense comparator (107);
Described Sigma-delta modulator (101), for the analog signal f0 of input is modulated, the data flow I of output two-pass DINSAR
1, I
2, first via data flow I
1through first group of noncontact coupling capacitance (102A), output coupled signal is input to the positive input terminal of subtracter (104) after by first group of integrator (103A) integral operation; The second circuit-switched data stream I
2through second group of noncontact coupling capacitance (102B), output coupled signal is input to the negative input end of subtracter (104) after by second group of integrator (103B) integral operation;
Described subtracter (104), be used for the additive operation to two paths of differential signals, output difference value signal is to controllable gain amplifier (105), after controllable gain amplifier (105) is adjusted this difference signal, be input to forward comparator (106) and negative sense comparator (107) simultaneously;
Described forward comparator (106), for the positive threshold voltage U1 of the forward single pulse signal of controllable gain amplifier (105) output signal and setting is compared, by 0 to 1 jumping moment, export a square-wave pulse to rest-set flip-flop, wherein U at input signal
1value be no more than the difference signal of subtracter (104) output forward peak value 1/2nd;
Described negative sense comparator (107), for by the negative threshold voltage U of the negative sense single pulse signal of controllable gain amplifier (105) output signal and setting
2compare, by 1 to 0 jumping moment, export a square-wave pulse to rest-set flip-flop, wherein U at input signal
2=-U
1;
Described rest-set flip-flop (108), under the triggering for the square-wave pulse signal in above-mentioned two comparators output, produces and first via data flow I
1consistent data flow I
8be input to demodulator (109);
Described demodulator (109), for by data flow I
8be demodulated to and the analog signal f inputting from Sigma-delta modulator (101)
0consistent analog signal f
1.
2. the noncontact analog signal transmission device between moving component according to claim 1, is characterized in that Sigma-delta modulator (101) comprising: a comparator (201), a d type flip flop (202), an oscillator (203), a subtracter (204) and an integrator (205); The positive input terminal input analog signal f of comparator (201)
0, output output sampled signal I
0, this sampled signal is quantified as two-pass DINSAR data flow I by d type flip flop (202)
1and I
2, output to respectively two groups of noncontact coupling capacitances (102A, 102B), simultaneously first via data flow I
1be input to subtracter (204) and reference voltage U
0after=2.5V subtracts each other, the difference signal of output completes D/A by integrator (205) and transforms, the analog signal f of output
2feed back to the negative input end of comparator (201), oscillator (203) output signal is input to the input end of clock of d type flip flop (202) again.
3. the noncontact analog signal transmission device between moving component according to claim 1, it is characterized in that two groups of noncontact coupling capacitances (102A, 102B) form by two capacitor plates, and two moving component A, B mounted externally are upper, first group of noncontact coupling capacitance (102A) is by two capacitor plate H
1and H
3form two capacitor plate H
1and H
3in components A and part B mounted externally, horizontally slip along parts respectively; Second group of noncontact coupling capacitance (102B) is by two capacitor plate H
2and H
4form two capacitor plate H
2and H
4in components A and part B mounted externally, horizontally slip along parts respectively.
4. the noncontact analog signal transmission device between moving component according to claim 1, it is characterized in that being connected of Sigma-delta modulator (101) and two groups of noncontact coupling capacitances (102A, 102B), with being connected of two groups of noncontact coupling capacitances (102A, 102B) and two groups of integrators (103A, 103B), all adopt shielding conductor to connect.
5. the noncontact analog signal transmission device between moving component according to claim 2, is characterized in that subtracter (204) in Sigma-delta modulator (101) is by an operational amplifier V
1with four resistance R
1, R
2, R
3, R
4composition, data flow I
1by the 3rd resistance R
3be input to operational amplifier V
1positive input terminal, the 4th resistance R
4a termination operational amplifier V
1positive input terminal, other end ground connection, reference voltage U
0=2.5V is by the first resistance R
1be input to operational amplifier V
1negative input end, at operational amplifier V
1output by the second resistance R
2feed back to operational amplifier V
1negative input end.
6. the noncontact analog signal transmission device between moving component according to claim 5, is characterized in that four resistance R
1, R
2, R
3, R
4meet following relational expression:
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| CN106100682B (en) * | 2016-08-11 | 2018-07-10 | 广州金升阳科技有限公司 | Single channel, multiple signals isolation Transmission system and full duplex communication system |
| CN112615619B (en) * | 2020-12-22 | 2023-09-22 | 苏州邈航科技有限公司 | Three-threshold IF conversion circuit |
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|---|---|---|---|---|
| US6999518B1 (en) * | 2000-05-05 | 2006-02-14 | Industrial Technology Research Institute | Receiver and transmission in a transmission system |
| CN101834473A (en) * | 2010-05-21 | 2010-09-15 | 西安电子科技大学 | Resonant tracking non-contact power supply device and power supply method |
| CN102315698A (en) * | 2011-08-30 | 2012-01-11 | 杭州矽力杰半导体技术有限公司 | Magnetic field coupling-type non-contact electric energy transmission device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009284381A (en) * | 2008-05-26 | 2009-12-03 | Fujitsu Ltd | Signal propagation circuit and signal processing device |
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| US6999518B1 (en) * | 2000-05-05 | 2006-02-14 | Industrial Technology Research Institute | Receiver and transmission in a transmission system |
| CN101834473A (en) * | 2010-05-21 | 2010-09-15 | 西安电子科技大学 | Resonant tracking non-contact power supply device and power supply method |
| CN102315698A (en) * | 2011-08-30 | 2012-01-11 | 杭州矽力杰半导体技术有限公司 | Magnetic field coupling-type non-contact electric energy transmission device |
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| 谢楷，王鹰, 李小平，刘彦明.基于近场辐射的非接触式数字信号测试方法.《系统工程与电子技术》.2010,第32卷(第8期),第1604-1607页. * |
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