CN115828982A - Electromagnetic signal based rotary counting device and counting method - Google Patents
Electromagnetic signal based rotary counting device and counting method Download PDFInfo
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- CN115828982A CN115828982A CN202211677460.9A CN202211677460A CN115828982A CN 115828982 A CN115828982 A CN 115828982A CN 202211677460 A CN202211677460 A CN 202211677460A CN 115828982 A CN115828982 A CN 115828982A
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Abstract
The invention discloses a rotary counting device and a counting method based on electromagnetic signals, which comprise a tray and a rotary detection device, wherein the upper surface of the tray is in a partial metallization state, the rotary detection device comprises a coil, a pulse excitation circuit and a signal processing circuit, the coil comprises a transmitting coil and at least two receiving coils, and the signal processing circuit comprises a voltage amplification detection circuit and a signal processor; the pulse excitation circuit comprises a resistor R 4 Capacitor C 4 An inverter P 1 And an inverter P 2 The voltage output end of the signal processor is connected with the capacitor C in sequence 4 An inverter P 1 And an inverter P 2 Connected in series, resistor R 4 One end of the capacitor is grounded, and the other end of the capacitor is connected with a capacitor C 4 And an inverter P 1 Make the capacitance C between 4 And a resistance R 4 Forming a differentiating circuit; the invention uses the signal processing algorithm to replace the comparator, and the counting accuracy and the anti-interference performance of the counting device are improved by a reliable interface output mode after internal counting.
Description
Technical Field
The invention relates to the technical field of metering, in particular to a rotary counting device and a counting method based on electromagnetic signals.
Background
The existing rotation counting technology comprises a magnetic sensing metering technology, an LC oscillation excitation metering technology and a coil excitation voltage comparison metering technology.
In the magnetic sensing metering technology, the sensors mostly adopt reed switches and Hall elements, and the sensors have magnetic characteristics and emit pulse signals under the action of a magnetic field, but have obvious defects, for example, the reed switches are packaged by glass, and burst phenomenon occurs in areas with large weather temperature difference and during transportation, and the reed switches cannot be used for high-precision metering due to limited action times; the Hall element is a moisture-sensitive device and is easily influenced by humidity, so that the static current of the device is large, and the battery of the metering equipment is consumed in advance; these magnetic sensors also have a common disadvantage in that the proximity of the magnet causes problems in the metering, and in the magnetic metering-based devices, the permanent magnet is in a rotating position, and when the magnetic sensor passes near the magnet, the magnetic sensor acts, but is easily interfered by external magnetism, and metering errors are caused.
The non-magnetic metering can realize metering without magnet triggering, has higher stability, high precision and stronger anti-interference capability, and slowly replaces magnetic metering. However, in the sensor based on LC oscillation, the rotating part adopts a metalized disc, the damping can be changed when the rotating part is close to the disc, the requirement on inductance is high by the way of LC excitation through outputting pulses by a comparator, the inductance requires large inductance value under the condition of increasing the distance, but an iron core is arranged in the middle of a large inductor and is greatly influenced by strong magnetism, and the hollow inductor can cause very weak energy and insufficient distance, so that the practical application is very poor; the LC oscillation mode has no magnetic metering limited to distance, and needs to use iron core inductor, which is affected by strong magnetic to affect inductance effect, so that it does not get rid of interference of magnet, and is a transition technology between magnetic metering technology and non-magnetic metering technology
The coil excitation voltage comparison and measurement technology mainly adopts the technical scheme that coil voltage is input into a comparator to be compared pairwise, and weak signals are easily influenced by interference to cause error measurement; there is also a way of comparing by using a predetermined voltage comparison reference, which is obtained by manually controlling the calibration operation when in use; the interference resistance is increased by increasing more transmitting coils and receiving coils, but the occupied space is larger, and the method cannot be suitable for the requirement of miniaturization.
Disclosure of Invention
Aiming at the defects existing in the problems, the invention provides a rotary counting device and a counting method based on electromagnetic signals.
In order to achieve the above object, the present invention provides a rotation counting device based on electromagnetic signals, comprising a tray rotating around the center thereof and a rotation detection device which is located above the tray and is fixed, wherein the upper surface of the tray is in a partially metallized state, the rotation detection device comprises a PCB coil, a pulse excitation circuit and a signal processing circuit, the PCB coil comprises a transmitting coil parallel to the upper plane of the tray and at least two receiving coils which are circumferentially arranged along the center of the transmitting coil at equal angles, the signal processing circuit comprises a voltage amplification detection circuit and a signal processor, and one end of each receiving coil is correspondingly connected with an input end of the voltage amplification detection circuit; the pulse excitation circuit comprises a resistor R 4 Capacitor C 4 An inverter P 1 And an inverter P 2 The voltage output end of the signal processor is sequentially connected with the capacitor C 4 An inverter P 1 And an inverter P 2 Connected in series, said resistor R 4 One end of the capacitor is grounded, and the other end of the capacitor is connected with the capacitor C 4 And the inverter P 1 Such that said capacitance C 4 And the resistance R 4 Forming a differentiating circuit;
wherein the signal processor controls the voltage to be switched between high and low to generate a rectangular signal, the differentiating circuit detects the edge spike signal of the rectangular signal, and the edge spike signal passes through the inverter P 1 Then through a capacitor C 5 Coupled to the voltage amplification detection circuit; then passes through an inverter P 2 Then through a capacitor C 6 Coupled to the transmit coil.
Preferably, the voltage amplification detection circuit includes a transistor Q 1 And a capacitor C 1 One end of the receiving coil is connected with the triode Q 1 The base electrode of (1), the triode Q 1 One end of the collector electrode is respectively connected with the capacitorC 1 One terminal, the signal processor, the capacitor C 1 The other end is grounded, and the triode Q 1 Is connected to the capacitor C 5 。
Preferably, in the initial state, the capacitor C in the voltage amplification detection circuit is subjected to 1 And (6) charging.
Preferably, the edge spike signal is a start signal of the voltage amplification detection circuit.
Preferably, after receiving the edge spike signal, the transmitting coil generates an electromagnetic signal and transmits the electromagnetic signal to the tray, and the receiving coil receives the electromagnetic signal reflected by the tray.
Preferably, after the receiving coil receives the electromagnetic signal, the edge spike signal starts the voltage amplification detection circuit, and the capacitor C starts the voltage amplification detection circuit 1 Discharging, after the rectangular signal is finished, the signal processor collects the capacitor C 1 The remaining voltage.
Preferably, the tray-covered metal area is a semicircle.
The invention also provides a rotary counting method based on electromagnetic signals, which adopts the rotary counting device based on electromagnetic signals and comprises the following steps:
the signal processor controls the voltage thereof to be switched between high and low to generate a rectangular signal;
the differentiating circuit detects the edge sharp pulse signal of the rectangular signal;
the edge spike signal passes through a phase inverter P 1 Then through a capacitor C 5 The voltage amplification detection circuit is coupled to the power supply and used as a starting signal of the voltage amplification detection circuit;
the edge spike signal passes through a phase inverter P 2 Then through a capacitor C 6 Coupled to the transmit coil;
after receiving the edge spike pulse signal, the transmitting coil generates an electromagnetic signal and transmits the electromagnetic signal to the tray, and the receiving coil receives the electromagnetic signal reflected by the tray;
after the receiving coil receives the electromagnetic signal, the receiving coil is used for receiving the electromagnetic signalCapacitor C in voltage amplification detection circuit 1 Discharging, after the rectangular signal is finished, the signal processor collects the capacitor C 1 A residual voltage signal;
counting a maximum value and a minimum value of the voltage signal based on the voltage signal;
converting the voltage signal into a square wave based on the maximum value and the minimum value of the voltage signal;
and obtaining the rotating direction and the rotating times of the tray based on the square wave.
Preferably, in the initial state, the capacitor C in the voltage amplification detection circuit is subjected to 1 And (6) charging.
Preferably, the obtaining of the rotation direction and the rotation number of the tray based on the square wave includes:
the square wave comprises a high voltage state and a low voltage state;
the two square waves formed by the receiving coils have four states, including low voltage and low voltage, low voltage and high voltage, high voltage and high voltage, and high voltage and low voltage;
based on the four states, the rotation direction and the rotation times of the tray are obtained.
Compared with the prior art, the invention has the beneficial effects that:
the invention uses the signal processing algorithm to replace the comparator, and the counting accuracy and the anti-interference performance of the counting device are improved by a reliable interface output mode after internal counting.
Drawings
FIG. 1 is a structural diagram of a rotary counting device based on electromagnetic signals according to the present invention;
FIG. 2 is a circuit diagram of an electromagnetic signal based revolution counting device of the present invention;
FIG. 3 is a diagram of voltage signals in the device for rotary counting based on electromagnetic signals according to the present invention;
fig. 4 is a square wave plot of the fig. 3 transformation.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Referring to fig. 1, the present invention provides a rotation counting apparatus based on electromagnetic signals, comprising:
the rotary detection device comprises a PCB coil, a pulse excitation circuit and a signal processing circuit, wherein the PCB coil comprises a transmitting coil 1 parallel to the upper plane of the tray 9 and at least two receiving coils 2 which are circumferentially arranged along the center of the transmitting coil 1 at equal angles, and 3 receiving coils are 2-1, 2-2 and 2-3 as shown in figure 1;
specifically, the tray 9 is circular, a rotating motor for rotating the tray 9 is arranged below the tray 9, the covered metal area 7-2 is preferably a semicircle, the center of the semicircle is concentric with the transmitting coil 1, and the rest is the uncovered metal area 7-1; other cases may be counted, such as the metal area 7-2 covering a 240 ° circle with a center that is not concentric with the transmitter coil 1; the distance between the tray 9 and the rotation detecting means is different in different cases, preferably the largest. The PCB coil is provided on the PCB board 8. The signal processor is a singlechip.
Referring to fig. 2, the signal processing circuit includes a voltage amplification detection circuit and a signal processor, and one end of each receiving coil 2 is correspondingly connected to an input end of the voltage amplification detection circuit; the pulse excitation circuit comprises a resistor R 4 Capacitor C 4 An inverter P 1 And an inverter P 2 The voltage output end of the signal processor is connected with the capacitor C in sequence 4 An inverter P 1 And an inverter P 2 Connected in series, resistor R 4 One end is grounded, and the other end is connected with a capacitor C 4 And an inverter P 1 Make the capacitance C between 4 And a resistance R 4 Forming a differentiating circuit;
wherein the signal processor controls the voltage to be switched between high and low to generate a rectangular signal, the differentiating circuit detects the edge spike signal of the rectangular signal, and the edge spike signal passes through the inverter P 1 Then through a capacitor C 5 Coupled to the voltage amplification detection circuit; then passes through an inverter P 2 Then through a capacitor C 6 Coupled to the transmitting coil 1.
Further, the voltage amplification detection circuit comprises a triode Q 1 And a capacitor C 1 One end of the receiving coil 2 is connected with a triode Q 1 Base electrode of (1), triode Q 1 One end of the collector is respectively connected with a capacitor C 1 One terminal, a signal processor, and a capacitor C 1 The other end is grounded, a triode Q 1 Transmitting set connection capacitor C 5 。
In this embodiment, in the initial state, the capacitance C in the voltage amplification detection circuit is detected 1 Charging; the edge sharp pulse signal is a starting signal of the voltage amplification detection circuit; after receiving the edge spike pulse signal, the transmitting coil 1 generates an electromagnetic signal and transmits the electromagnetic signal to the tray 9, and the reflected electromagnetic signal intensities of the areas made of different materials on the tray 9 are different, so that the influence of the electromagnetic signal intensity received by the receiving coil 2 is periodic and can be converted into a voltage signal which changes periodically. The receiving coil 2 receives the electromagnetic signal reflected by the tray 9; after the receiving coil 2 receives the electromagnetic signal, the edge spike pulse signal starts the voltage amplification detection circuit and the capacitor C 1 Discharging, and acquiring a capacitor C by a signal processor after the rectangular signal is finished 1 The remaining voltage.
The invention also provides a rotary counting method based on electromagnetic signals, which adopts the rotary counting device based on electromagnetic signals and comprises the following steps:
at initial state, amplifying the capacitor C in the detection circuit 1 Charging;
the signal processor controls the voltage thereof to be switched between high and low to generate a rectangular signal;
the differentiating circuit detects the edge sharp pulse signal of the rectangular signal;
edge spike signal passes throughInverter P 1 Then through a capacitor C 5 The voltage amplification detection circuit is coupled to the power supply and used as a starting signal of the voltage amplification detection circuit;
the edge spike signal passes through the phase inverter P 2 Then through a capacitor C 6 Coupled to the transmitting coil 1;
after receiving the edge spike pulse signal, the transmitting coil 1 generates an electromagnetic signal and transmits the electromagnetic signal to the tray 9, and the receiving coil 2 receives the electromagnetic signal reflected by the tray 9;
after the receiving coil 2 receives the electromagnetic signal, the capacitor C in the voltage amplification detection circuit 1 Discharging, and acquiring a capacitor C by a signal processor after the rectangular signal is finished 1 A residual voltage signal;
counting the maximum value and the minimum value of the voltage signal based on the voltage signal;
converting the voltage signal into a square wave based on the maximum value and the minimum value of the voltage signal;
based on the square wave, the rotation direction and the number of rotations of the tray 9 are obtained.
Further, based on the square wave, obtaining the rotation direction and the number of rotations of the tray 9 includes:
the square wave comprises a high voltage state and a low voltage state;
the two square waves formed by the receiving coil 2 have four states, including low voltage and low voltage, low voltage and high voltage, high voltage and high voltage, and high voltage and low voltage;
based on the four states, the rotation direction and the number of rotations of the tray 9 are obtained.
With reference to fig. 3 and 4, the counting process obtained on the basis of the two square waves formed by the receiving coil 2:
converting the voltage signals acquired by the receiving coil 2 into 2 voltage signals which are obtained by converting the logic receiving coil 2 with an included angle of 90 degrees according to the sine and cosine relationship, and calling the voltage signals as two counting signals; because the discharge position of the receiving coil 2 has no two orthogonal symmetry axes, the voltage signals obtained by converting the discharge position of the receiving coil 2 into 2 logic receiving coils 2 with 90-degree included angles according to the sine and cosine relation according to the position angle of the receiving coil 2;
the two counting signals are respectively subjected to change tracking, and the rising trend and the falling trend of the two counting signals are counted so as to respectively determine the central positions, namely central values, of the two counting signals. According to the two central values, an upper threshold value and a lower threshold value are respectively set, the two counting signals are converted into two counting square waves by using a bistable hysteresis comparison mode of a Schmitt trigger, the two square waves respectively have two states of high voltage and low voltage, and the two square waves are correspondingly combined into 4 necessary counting states, namely low-low state, low-high state, high-high state and high-low state without other possibility.
According to the transition periodicity and the sequence of the 4 counting states, the rotation can be performed in a 360-degree forward rotation or a reverse rotation respectively, so that the forward and reverse rotation counting of the rotating device can be realized.
The counting by the 4 counting states has the following functional characteristics:
can distinguish forward and reverse rotation, 4 counting states, and the state transition sequence is different when the forward and reverse rotation is carried out, such as
Forward direction: low-low = > low-high = > high-low = > low-low
And (3) reversing: low-low < = low-high < = high-low < = low
The sequentiality to 4 counting state migrations is judged, can prevent that the counting state from leading to abnormal migration and wrong count because of external disturbance, has improved the accuracy and the interference immunity of count, and abnormal state migration includes: if such state transition occurs due to disturbance, it is detected and ignored, preventing erroneous counting.
After 4 counting state transition periods are completed for a plurality of times, counting signals in the periods to obtain a new central value, comparing the new central value with the current central value to obtain a central value deviation direction, calibrating the central value according to the direction to adapt to the influence of environmental change and external interference on the counting signals, and enhancing the counting accuracy of the counting device.
When the counting environment is greatly changed, for example, the environmental temperature is greatly changed, the tray 9 is greatly deformed, a new tray 9 is replaced, and the like, at this time, normal transition of the counting state may not be completed because the central value is actually greatly changed. At the moment, the change tracking of the two counting signals which is continuously carried out all the time can automatically determine a new central value again according to the ascending and descending trends obtained by statistics, so that the counting is continued without manual intervention, and the environmental adaptability and the use convenience of the counting device are enhanced.
In this embodiment, the output mode of the counting apparatus is: when counting, the counting value is internally accumulated and kept for inquiry or timing notification at any time. The counting device detects the counting, automatically accumulates and keeps the counting value in an internal memory (such as a memory of a singlechip), and the counting value data is transmitted by a byte stream with a preset format by using a Universal Asynchronous Receiver Transmitter (UART). The UART is a universal and reliable bidirectional digital signal transmission interface, data is transmitted in a byte stream mode according to a bit sequence, various single-chip microcomputers and PCs (personal computers) support the interface, and the interface has no problem that a pulse signal interface is easy to interfere. The counting device internally accumulates and maintains the counting value, outputs the forward and reverse counting values in a reliable Universal Asynchronous Receiver Transmitter (UART) mode, can periodically and actively send out when the counting is changed or send out according to the requirement of an application party as required, and solves the defect of adopting a voltage pulse mode to output.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A rotary counting device based on electromagnetic signals comprises a tray rotating around the center of the tray and a rotary detection device which is positioned above the tray and is immovable, wherein the upper surface of the tray is in a partial metallization state, the rotary detection device comprises a PCB coil, a pulse excitation circuit and a signal processing circuit, and the PCB coil comprises a transmitting coil and a transmitting coil parallel to the upper plane of the tray, and a signal processing circuitThe receiving coil comprises at least two receiving coils which are circumferentially arranged along the center of the transmitting coil at equal angles, and is characterized in that the signal processing circuit comprises a voltage amplification detection circuit and a signal processor, wherein one end of each receiving coil is correspondingly connected with the input end of one voltage amplification detection circuit; the pulse exciting circuit comprises a resistor R 4 Capacitor C 4 An inverter P 1 And an inverter P 2 The voltage output end of the signal processor is sequentially connected with the capacitor C 4 An inverter P 1 And an inverter P 2 Connected in series, said resistor R 4 One end of the capacitor is grounded, and the other end of the capacitor is connected with the capacitor C 4 And the inverter P 1 Such that the capacitance C 4 And the resistance R 4 Forming a differentiating circuit;
wherein the signal processor controls the voltage to be switched between high and low to generate a rectangular signal, the differentiating circuit detects the edge spike signal of the rectangular signal, and the edge spike signal passes through the inverter P 1 Then through a capacitor C 5 Coupled to the voltage amplification detection circuit; then passes through an inverter P 2 Then through a capacitor C 6 Coupled to the transmit coil.
2. The electromagnetic signal based revolution counting device of claim 1, wherein the voltage amplification detection circuit comprises a triode Q 1 And a capacitor C 1 One end of the receiving coil is connected with the triode Q 1 The base electrode of (1), the triode Q 1 One end of the collector is respectively connected with the capacitor C 1 One terminal, the signal processor, the capacitor C 1 The other end is grounded, and the triode Q 1 Is connected to the capacitor C 5 。
3. The electromagnetic signal based revolution counting device of claim 2, wherein in an initial state, the capacitance C in the voltage amplification detection circuit is measured 1 And (6) charging.
4. The electromagnetic signal based revolution counting device of claim 3, wherein the edge spike signal is a start signal of the voltage amplification detection circuit.
5. The device according to claim 4, wherein the transmitting coil generates an electromagnetic signal and transmits the electromagnetic signal to the tray after receiving the edge spike signal, and the receiving coil receives the electromagnetic signal reflected by the tray.
6. The device according to claim 5, wherein the receiving coil receives the electromagnetic signal, and the edge spike signal activates the voltage amplification detection circuit, and the capacitor C 1 Discharging, after the rectangular signal is finished, the signal processor collects the capacitor C 1 The remaining voltage.
7. The electromagnetic signal based revolution counting device of claim 6, wherein the tray covered metal area is a semicircle.
8. An electromagnetic signal based rotation counting method, which adopts the electromagnetic signal based rotation counting device of any one of claims 1-7, and comprises:
the signal processor controls the voltage thereof to be switched between high and low to generate a rectangular signal;
the differentiating circuit detects the edge sharp pulse signal of the rectangular signal;
the edge spike signal passes through a phase inverter P 1 Then through a capacitor C 5 The voltage amplification detection circuit is coupled to the power supply and used as a starting signal of the voltage amplification detection circuit;
the edge spike signal passes through a phase inverter P 2 Then through a capacitor C 6 Coupled to the transmit coil;
after receiving the edge spike pulse signal, the transmitting coil generates an electromagnetic signal and transmits the electromagnetic signal to the tray, and the receiving coil receives the electromagnetic signal reflected by the tray;
after the receiving coil receives the electromagnetic signal, the capacitor C in the voltage amplification detection circuit 1 Discharging, after the rectangular signal is finished, the signal processor collects the capacitor C 1 A residual voltage signal;
counting a maximum value and a minimum value of the voltage signal based on the voltage signal;
converting the voltage signal into a square wave based on the maximum value and the minimum value of the voltage signal;
and obtaining the rotating direction and the rotating times of the tray based on the square wave.
9. The electromagnetic signal based revolution counting method of claim 8, characterized in that in an initial state, the capacitance C in the voltage amplification detection circuit is measured 1 And (6) charging.
10. The electromagnetic signal based revolution counting method of claim 9, wherein obtaining the rotation direction and the number of revolutions of the tray based on the square wave comprises:
the square wave comprises a high voltage state and a low voltage state;
the two square waves formed by the receiving coils have four states, including low voltage and low voltage, low voltage and high voltage, high voltage and high voltage, and high voltage and low voltage;
based on the four states, the rotation direction and the rotation times of the tray are obtained.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211677460.9A CN115828982A (en) | 2022-12-26 | 2022-12-26 | Electromagnetic signal based rotary counting device and counting method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211677460.9A CN115828982A (en) | 2022-12-26 | 2022-12-26 | Electromagnetic signal based rotary counting device and counting method |
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| CN115828982A true CN115828982A (en) | 2023-03-21 |
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| CN202211677460.9A Pending CN115828982A (en) | 2022-12-26 | 2022-12-26 | Electromagnetic signal based rotary counting device and counting method |
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