CN102780481B - Non-contact analog signal transmission device between moving parts - Google Patents

Abstract

The invention discloses a non-contact analog signal transmission device used between moving parts, which mainly solves the problems of analog signal distortion and poor anti-interference ability of the existing device; it includes a Sigma-delta modulator (101), two sets of coupling Capacitor (102A.102B), two sets of integrators (103A.103B), subtractor (104), controllable gain amplifier (105), two comparators (106.107), RS flip-flop (108) and demodulator ( 109); the Sigma-delta modulator modulates the input signal f ₀ to output two differential data streams, which are respectively input to two sets of coupling capacitors for coupling, and two sets of integrators, subtractors and controllable gain amplifiers form a differential charge amplifier, The data stream is extracted and amplified. The amplified data stream passes through two comparators, and outputs two square wave pulses to the RS flip-flop. The RS flip-flop outputs the final data stream under the trigger of the two square wave pulses. The demodulator The data stream is demodulated, and an analog signal f ₁ consistent with f ₀ is output. The invention has the advantages of simple structure, stable performance and high signal transmission precision.

Description

Non-contact analog signal transmission device between moving parts

technical field

The invention belongs to the technical field of communication, and relates to a device for non-contact analog signal transmission between moving parts, which can carry out non-contact analog signal transmission between moving parts.

Background technique

The data transmission between components mainly includes three types: energy transmission, analog transmission and digital transmission. If the non-contact transmission of these three types of signals can be realized between components, the components can achieve completely non-contact work and avoid friction loss of components. , making the equipment work safer and increasing the working life of the equipment.

Regarding the problem of non-contact energy transmission, the Chinese patent application "Resonance Tracking Non-Contact Power Supply Device and Power Supply Method" (public number: 101834473A) proposes a power supply device and method, which solves the problem of non-contact power transmission and makes wireless power transmission possible. A breakthrough has been made in high-power energy transmission.

The existing methods for non-contact digital transmission are mainly based on two technical means of wireless radio frequency transmission and optical transmission, and a large number of results have been achieved and commercial products have come out.

There are two main methods for the existing analog signal transmission of non-contact structures, one is through the slip ring structure, this structure does not realize real non-contact transmission; the other is through the microprocessor and AD to complete the analog signal transmission. The quantitative sampling of analog signals is converted into digital signal transmission, and then the analog signals are output through DA. This device can realize non-contact transmission of analog signals, but there are still the following defects:

1. Using a microprocessor, when faced with a complex electromagnetic environment, it is easy to cause a crash problem, resulting in transmission errors or interruptions, poor reliability, and high cost;

2. Use DA to output analog signal, the output waveform has steps, not smooth analog signal, which will cause distortion of analog signal.

Contents of the invention

The object of the present invention is to address the shortcomings of existing devices, and propose a non-contact analog signal transmission device between moving parts with simple structure, stable performance and easy implementation, so as to improve the accuracy of analog signal transmission.

In order to achieve the above object, the non-contact analog signal transmission device between the moving parts of the present invention is characterized in that it includes: a Sigma-delta modulator, two groups of non-contact coupling capacitors, two groups of integrators, a subtractor, a controllable gain amplifier, two a comparator, demodulator and RS flip-flop;

The Sigma-delta modulator is used to modulate the input analog signal f ₀ and output two differential data streams I ₁ and I ₂ , the first data stream I ₁ passes through the first group of coupling capacitors to output the coupling signal After being integrated by the first group of integrators, it is input to the positive input of the subtractor; the second data stream I ₂ passes through the second group of coupling capacitors, and the output coupling signal is input to the negative of the subtractor after being integrated by the second group of integrators. input terminal;

The subtractor is used to complete the subtraction operation of the two differential signals, output the differential signal to the controllable gain amplifier, and the controllable gain amplifier adjusts the differential signal, and simultaneously inputs it to the positive comparator and the negative comparator. to the comparator;

The positive comparator is used to compare the positive single pulse signal in the output signal of the subtractor with the set positive threshold voltage _U1 , and output a square wave pulse at the moment when the input signal changes from 0 to 1 For the RS flip-flop, where _U1 takes a value not exceeding one-half of the positive-going peak value of the difference signal output by the subtractor;

The negative comparator is used to compare the negative single pulse signal in the output signal of the subtractor with the set negative threshold voltage _U2 , and output a square wave pulse when the input signal changes from 1 to 0 Give the RS flip-flop where U ₂ =-U ₁ ;

The RS flip-flop is used to generate a data stream I ₈ consistent with the first data stream I ₁ and input it to the demodulator under the trigger of the square wave pulse signal output by the above two comparators;

The demodulator is used to demodulate the data stream I ₈ into an analog signal f ₁ consistent with the analog signal f ₀ input from the Sigma-delta modulator.

The non-contact analog signal transmission device between the above-mentioned moving parts is characterized in that the Sigma-delta modulator includes: a comparator, a D flip-flop, an oscillator, a subtractor and an integrator; The input terminal inputs the analog signal f ₀ , and the output terminal outputs the sampling signal I ₀ , the sampling signal is quantized into two differential data streams I ₁ and I ₂ through the D flip-flop, which are respectively output to two sets of coupling capacitors, while the first data stream After I ₁ is input to the subtractor and subtracted from the reference voltage U ₀ =2.5V, the output difference signal is converted to D/A through the integrator, and the output analog signal f ₂ is fed back to the negative input terminal of the comparator, and the oscillator The output signal is input to the clock input of the D flip-flop.

The above-mentioned non-contact analog signal transmission device between moving parts is characterized in that the two sets of non-contact coupling capacitors are composed of two capacitor plates, and are installed on the two external moving parts A and B, that is, the first The first group of non-contact coupling capacitors is composed of two capacitor plates _H1 and _H3 , and the two capacitor plates _H1 and _H3 are installed on the external part A and part B respectively, and slide left and right along the parts; the second group of non-contact The coupling capacitor is composed of two capacitor plates H ₂ and H ₄ , and the two capacitor plates H ₂ and H ₄ are installed on the external part A and part B respectively, and slide left and right along the part.

The above-mentioned non-contact analog signal transmission device between moving parts is characterized in that the subtractor is composed of an operational amplifier V ₁ and four resistors R ₁ , R ₂ , R ₃ , and R ₄ , and the data stream I ₁ passes through the third Resistor R ₃ is input to the positive input terminal of the operational amplifier _V1 , one end of the fourth resistor _R4 is connected to the positive input terminal of the operational amplifier _V1 , and the other end is grounded, and the reference voltage U ₀ =2.5V is input to the operational amplifier through the first resistor _R1 The negative input terminal of the amplifier _V1 is fed back to the negative input terminal of the operational amplifier _V1 through the second resistor _R2 at the output terminal of the operational amplifier _V1 , and the four resistors satisfy the relational expression:

$\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}<span\; class="notranslate">\; .</span>$

Compared with the existing device for non-contact data transmission, the present invention has the following advantages:

1, the present invention is owing to have only used comparator, operational amplifier, D flip-flop and a small amount of resistance capacitance, circuit structure is simple, and cost is low;

2. Since the present invention uses a demodulator and a modulator to complete signal conversion, it does not use a microprocessor, works stably, and can cope with complex electromagnetic environments;

3. The present invention uses a low-pass filter for demodulation in the output of the subsequent stage, so the precision of the output analog signal is high. The present invention will be further described below in conjunction with accompanying drawing:

Description of drawings

Fig. 1 is the overall structural diagram of device of the present invention;

Fig. 2 is a schematic diagram of a Sigma-delta modulator circuit in the present invention;

Fig. 3 is a structural schematic diagram of two groups of non-contact coupling capacitors in the present invention;

Fig. 4 is a schematic diagram of the installation positions of two sets of non-contact coupling capacitors in the embodiment of the present invention.

Detailed ways

With reference to Fig. 1, the non-contact analog signal transmission device between moving parts of the present invention comprises Sigma-delta modulator 101, two groups of non-contact coupling capacitors 102A and 102B, two groups of integrators 103A and 103B, subtractor 104, controllable Gain amplifier 105 , two comparators 106 and 107 , RS flip-flop 108 and demodulator 109 . The Sigma-delta modulator 101 is used to modulate the input analog signal f ₀ and output two differential data streams I ₁ and I ₂ ; the two groups of non-contact coupling capacitors 102A and 102B are used for the two differential data streams I ₁ and I ₂ non-contact transmission, wherein the first data stream I ₁ outputs the third data stream I ₃ after passing through the first group of coupling capacitors 102A, and the second data stream I ₂ outputs after passing through the second group of coupling capacitors 102B The fourth data stream I ₄ ; the two groups of integrators 103A and 103B, the subtractor 104 and the controllable gain amplifier 105 together form a differential charge amplifier for extracting and amplifying two data streams I ₃ and I ₄ ; the positive The comparator 106 is used to compare the positive single pulse signal in the output signal _I5 of the controllable gain amplifier 105 with the set positive threshold voltage _U1 , _and output a The square wave pulse is given to the RS flip-flop 108, and the negative comparator 107 is used to compare the negative single pulse signal in the output signal I ₅ of the controllable gain amplifier 105 with the set negative threshold voltage U ₂ , and the input signal I ₅ From 1 to 0 transition moment, output a square wave pulse to RS flip-flop 108; RS flip-flop 108 is used to generate the first road data stream I with the triggering of the square wave pulse signal output by the above-mentioned two comparators. The _consistent data stream I ₈ is input to the demodulator 109, and the demodulator 109 is used to demodulate the data stream I ₈ into an analog signal f ₁ consistent with the analog signal f ₀ input from the Sigma-delta modulator 101.

In this embodiment, a thermocouple is used to measure the temperature of the oil well drill bit when it is working, and the non-contact analog signal transmission device between the moving parts of the present invention is used to transmit the measurement results to an external display device. The whole device is divided into a data sending part and a data receiving part, the data sending part is installed inside the drill bit and connected with the thermocouple temperature measuring system, and the data receiving part is installed on the external base and connected with the display device.

The thermocouple installed inside the drill bit measures the temperature of the drill bit and transmits the measured temperature data to the data sending part.

The data transmission part includes a Sigma-delta modulator 101, as shown in Figure 2, it is made up of a comparator 201, a D flip-flop 202, an oscillator 203, a subtractor 204 and an integrator 205, wherein, the subtraction The device 204 is composed of an operational amplifier V ₁ and four resistors R ₁ , R ₂ , R ₃ , and R ₄ , and the four resistors R ₁ , R ₂ , R ₃ , and R ₄ satisfy the following relationship:

$\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}<span\; class="notranslate">\; ;</span>$

Integrator 205 is made up of a resistor _R5 and a capacitor _C1 ; thermocouple measures the temperature T of the drill bit, and the temperature data is input to the positive input terminal of the comparator 201, and the comparator output sampling signal _T0 is input to the D flip-flop 202, oscillating The output signal of the device 203 is input to the clock input end of the D flip-flop 202, where the frequency of the oscillator 203 is f=500kHz, that is, the input clock of the D flip-flop 202 is 500kHz; the D flip-flop 202 quantizes the sampling signal _T0 as Two differential data streams I ₁ and I ₂ , wherein the first data stream I ₁ is output to the first group of coupling capacitors 102A, and the second data stream I ₂ is output to the second group of coupling capacitors 102B; at the same time, the first data stream The current I ₁ is input to the positive input terminal of the operational amplifier V ₁ through the third resistor R ₃ , one end of the fourth resistor R ₄ is connected to the positive input terminal of the operational amplifier V ₁ , and the other end is grounded; the reference voltage U ₀ =2.5V passes through the first Resistor _R1 is input to the negative input terminal of the operational amplifier _V1 , and is fed back to the negative input terminal of the operational amplifier _V1 through the second resistor _R2 at the output terminal of the operational amplifier _V1 ; the output terminal of the operational amplifier _V1 is passed through the fifth resistor R ₅ is connected to the capacitor C ₁ , and the other end of the capacitor C ₁ is grounded; the temperature signal f ₂ is drawn from the node of the fifth resistor R ₅ and the capacitor C ₁ and fed back to the negative input terminal of the operational amplifier V ₁ .

Two sets of non-contact coupling capacitors 102A and 102B are composed of two capacitive plates, the structural diagram of which is shown in Figure 3, wherein the first group of non-contact coupling capacitors 102A is composed of two capacitive plates _H1 and _H3 , the second The two sets of non-contact coupling capacitors 102B are composed of two capacitor plates _H2 and _H4 . The installation positions of these two non-contact coupling capacitors are shown in Figure 4, where Figure 4(a) is an overall schematic diagram of the drill bit and the base , the drill bit is installed inside the base, and the drill bit can rotate around the base; Figure 4(b) is the installation position diagram of the capacitor plate H ₁ and the capacitor plate H ₂ on the drill bit, the capacitor plate H ₁ and the capacitor plate H ₂ are ring-shaped conductors, fixed on the outer surface of the drill bit, the capacitor plate H ₁ is connected to the output terminal Q of the Sigma-delta modulator 101 with a shielded wire, and the capacitor plate H ₂ is connected to the Sigma-delta modulator 101 the output of Connected with shielded wires; Figure 4(c) is the installation position diagram of capacitor plate _H3 and capacitor plate _H4 on the base, both capacitor plate _H3 and capacitor plate _H4 are ring-shaped conductors, Fixed on the inner surface of the base, the capacitor plate _H3 is connected with the first group of integrators 103A with shielded wires, and the capacitor plate _H4 is connected with the second group of integrators 103B with shielded wires.

The data receiving section includes two sets of integrators 103A and 103B, a subtractor 104 , a controllable gain amplifier 105 , two sets of comparators 106 and 107 , an RS flip-flop 108 and a demodulator 109 . The third differential data stream _I3 coupled through the first set of coupling capacitors 102A is input to the positive input terminal of the subtractor 104 after passing through the first set of integrators 103A, and the fourth differential data stream coupled through the second set of coupling capacitors 102B I ₄ is input to the negative input terminal of the subtractor 104 after passing through the second group of integrators 103B; the subtractor 104 outputs the differential data stream I ₅ to the controllable gain amplifier 105, and the differential data stream I ₅ is amplified, and output two ways after amplification Signals I ₆ and I ₇ , where I ₆ is input to the positive comparator 106, compared with the set positive threshold voltage U ₁ =1V, and at the moment when I ₆ transitions from 0 to 1, a square wave pulse h is output ₁ to the input terminal R of the RS flip-flop 108; I ₇ is input to the negative comparator 107, and compared with the set negative threshold voltage U ₂ =-1V, when I ₇ jumps from 1 to 0, a The square wave pulse h ₂ is sent to the input terminal S of the RS flip-flop 108; under the triggering of the square wave pulse signals h ₁ and h ₂ , the RS flip-flop generates a data stream I ₈ input consistent with the first data stream I ₁ to the demodulator 109; the demodulator 109 demodulates the data stream I ₈ into an analog signal f ₁ consistent with the analog signal f ₀ input from the Sigma-delta modulator 101 .

The analog signal _f1 output from the demodulator 109 is the temperature T measured by the thermocouple, and the data sending part of the device is used to send the temperature T from the inside of the drill to the data receiving part installed on the base, and the data receiving part of the base It is connected with an external display device, and the temperature data is input to the display device to realize real-time monitoring of the drill bit temperature.

The above embodiment is only a reference description of the present invention, and does not constitute any limitation to the content of the present invention. Obviously, different forms of structural changes can be made under the concept of the present invention, but these are all included in the protection of the present invention.

Claims (6)

1. A non-contact analog signal transmission device between moving parts, characterized in that it comprises: a Sigma-delta modulator (101), two groups of non-contact coupling capacitors (102A, 102B), two groups of integrators (103A, 103B) , subtractor (104), controllable gain amplifier (105), two comparators (106, 107), demodulator (109) and RS flip-flop (108), two comparators (106, 107) include positive To comparator (106) and negative comparator (107); The Sigma-delta modulator (101) is used to modulate the input analog signal f0, output two differential data streams I ₁ , I ₂ , and the first data stream I ₁ passes through the first group of non-contact coupling capacitors (102A), the output coupling signal is input to the positive input end of the subtractor (104) after the integral operation of the first group of integrators (103A); the second road data flow I ₂ passes through the second group of non-contact coupling capacitors (102B), The output coupling signal is input to the negative input terminal of the subtractor (104) after the integral operation of the second group of integrators (103B); The subtractor (104) is used to complete the subtraction operation of the two differential signals, and output the difference signal to the controllable gain amplifier (105), after the controllable gain amplifier (105) adjusts the difference signal, Input to positive comparator (106) and negative comparator (107) simultaneously; The positive comparator (106) is used to compare the positive single pulse signal in the output signal of the controllable gain amplifier (105) with the set positive threshold voltage U1, when the input signal jumps from 0 to 1 Moment, output a square wave pulse to the RS flip-flop, wherein the value of _U1 is no more than 1/2 of the forward peak value of the difference signal output by the subtractor (104); The negative comparator (107) is used to compare the negative single-pulse signal in the output signal of the controllable gain amplifier (105) with the set negative threshold voltage _U2 , and when the input signal jumps from 1 to 0 Change time, output a square wave pulse to RS flip-flop, wherein U ₂ =-U ₁ ; The RS flip-flop (108) is used to generate a data stream _I8 consistent with the first data stream _I1 and input it to the demodulator (109) under the triggering of the square wave pulse signals output by the above-mentioned two comparators ; The demodulator (109) is used to demodulate the data stream I ₈ into an analog signal f ₁ consistent with the analog signal f ₀ input from the Sigma-delta modulator (101). 2. The non-contact analog signal transmission device between moving parts according to claim 1, characterized in that the Sigma-delta modulator (101) comprises: a comparator (201), a D flip-flop (202), an oscillator device (203), a subtractor (204) and an integrator (205); the positive input terminal of the comparator (201) inputs the analog signal f ₀ , and the output terminal outputs the sampling signal I ₀ , and the sampling signal passes through the D flip-flop ( 202) is quantized into two differential data streams I ₁ and I ₂ , which are respectively output to two sets of non-contact coupling capacitors (102A, 102B), while the first data stream I ₁ is input to the subtractor (204) and the reference voltage U ₀ After =2.5V is subtracted, the difference signal of output finishes D/A conversion by integrator (205), and the analog signal _f of output feeds back to the negative input terminal of comparator (201) again, and oscillator (203) output signal Input to the clock input of D flip-flop (202). 3. The non-contact analog signal transmission device between moving parts according to claim 1, characterized in that two groups of non-contact coupling capacitors (102A, 102B) are composed of two capacitor plates, and are installed on two external On the moving parts A and B, that is, the first group of non-contact coupling capacitors (102A) is composed of two capacitor plates H ₁ and H ₃ , and the two capacitor plates H ₁ and H ₃ are respectively installed on the external part A and part On B, slide left and right along the component; the second group of non-contact coupling capacitors (102B) is composed of two capacitor plates H ₂ and H ₄ , and the two capacitor plates H ₂ and H ₄ are respectively installed on the external part A and part On B, slide left and right along the widget. 4. The non-contact analog signal transmission device between moving parts according to claim 1, characterized in that the Sigma-delta modulator (101) is connected with two groups of non-contact coupling capacitors (102A, 102B), and two groups of non-contact The connections between the contact coupling capacitors (102A, 102B) and the two sets of integrators (103A, 103B) are all connected by shielded wires. 5. The non-contact analog signal transmission device between moving parts according to claim 2, characterized in that the subtractor (204) in the Sigma-delta modulator (101) consists of an operational amplifier V ₁ and four resistors R ₁ , R ₂ , R ₃ , R ₄ , the data stream I ₁ is input to the positive input terminal of the operational amplifier V ₁ through the third resistor R ₃ , one end of the fourth resistor R ₄ is connected to the positive input terminal of the operational amplifier V ₁ , and the other One end is grounded, the reference voltage U ₀ =2.5V is input to the negative input terminal of the operational amplifier V ₁ through the first resistor R ₁ , and the output terminal of the operational amplifier V ₁ is fed back to the negative input terminal of the operational amplifier V ₁ through the second resistor R ₂ end. 6. The non-contact analog signal transmission device between moving parts according to claim 5, characterized in that the four resistors R ₁ , R ₂ , R ₃ , and R ₄ satisfy the following relationship: $\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}}{{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}<span\; class="notranslate">\; .</span>$