Passive wireless vibration sensing device and system
By using a passive wireless vibration sensing device, passive monitoring is achieved by utilizing radio frequency energy and equipment vibration energy, which solves the problems of high cost and complex wiring in existing technologies and realizes high-precision passive vibration monitoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICHUAN LUTIANHUA
- Filing Date
- 2025-07-31
- Publication Date
- 2026-06-23
AI Technical Summary
Existing technologies for vibration monitoring suffer from high costs, the need for external power supply, and complex wiring, making passive wireless monitoring particularly difficult in explosion-proof areas.
A passive wireless vibration sensing device is adopted, which utilizes the radio frequency energy transmitted by the reader and the vibration energy of the equipment. Passive vibration monitoring is achieved through an antenna group, a frequency converter, a phase modulation device and a piezoelectric device. The process includes the antenna group receiving radio frequency signals, frequency conversion, the piezoelectric device sensing vibration and the phase modulation device modulating the phase before transmitting the signal.
It enables passive vibration monitoring without the need for batteries or wired power, reducing maintenance and construction costs and improving sensing accuracy.
Smart Images
Figure CN224398800U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of passive vibration monitoring, specifically relating to a passive wireless vibration sensing device and system. Background Technology
[0002] For many large pieces of equipment in chemical plants, the vast majority of their failures are closely related to mechanical motion or vibration. Vibration monitoring is characterized by its directness, real-time capability, and broad coverage of failure types. Currently, vibration monitoring is a core technology for various predictive maintenance procedures for large equipment.
[0003] To achieve high-precision, real-time vibration monitoring, active or wired technologies are currently the primary methods employed. However, these methods are costly. Active sensors require a continuous external power supply, increasing energy consumption and necessitating the installation of dedicated power lines. This is particularly problematic for existing factory areas, where the costs of initial construction and subsequent maintenance are substantial. Furthermore, vibration monitoring of critical equipment within explosion-proof areas remains a pressing challenge.
[0004] Therefore, in view of the above-mentioned shortcomings in the prior art, this utility model discloses a passive wireless vibration sensing device and system. Utility Model Content
[0005] This utility model discloses a passive wireless vibration sensing device and system, which can monitor vibration in real time without the need for a power source.
[0006] This utility model is achieved through the following technical solution:
[0007] A passive wireless vibration sensing device includes an antenna group, the antenna group including at least one antenna, the antenna group being connected to a frequency converter, the antenna group being connected to a phase modulation device, the frequency converter being connected to the phase modulation device, and the phase modulation device being connected to a piezoelectric device.
[0008] The antenna array receives radio frequency (RF) signals and transmits them to a frequency converter. The frequency converter transforms a passive mixer signal at frequency f1 into an RF signal at frequency f2. A piezoelectric sensor detects the vibration level in the environment and outputs a corresponding voltage. A phase-modulating device alters the phase of the RF signal at frequency f2 based on the voltage generated by the piezoelectric sensor and transmits the phase-modulated signal to the transmitting end of the antenna array.
[0009] To better realize this utility model, the frequency conversion device further includes a first inductor, a first varactor diode, and an LC parallel resonant unit. The first inductor and the first varactor diode are connected in series. The input terminal of the first inductor is connected to the receiving terminal of the antenna group. The output terminal of the first varactor diode is connected to the input terminal of the LC parallel resonant unit and the phase modulation device, respectively.
[0010] To better realize this utility model, the LC parallel resonant unit further includes a second inductor and a first capacitor. The input terminal of the second inductor and the input terminal of the first capacitor are connected in parallel and then connected to the output terminal of the first varactor diode.
[0011] To better realize this utility model, the phase modulation device further includes an orthogonal coupler, a first LC series resonant unit, and a second LC series resonant unit. The input port of the orthogonal coupler is connected to the output terminal of the frequency converter through a second matching network. The through port of the orthogonal coupler is connected to the first LC series resonant unit. The coupling port of the orthogonal coupler is connected to the second LC series resonant unit. The isolation port of the orthogonal coupler is connected to the transmitting terminal of the antenna group through a fourth matching network.
[0012] To better realize this utility model, the orthogonal coupler further includes four branch line units with quarter-wavelength structures respectively corresponding to the input port, through port, coupling port and isolation port.
[0013] To better realize this utility model, the branch line unit of the corresponding isolation port is further connected to the second LC series resonant unit and the piezoelectric device respectively.
[0014] To better realize this utility model, the first LC series resonant unit further includes a third inductor and a second varactor diode, the third inductor and the second varactor diode are connected in series in sequence, and the input terminal of the third inductor is connected to the through port of the quadrature coupler.
[0015] To better realize this utility model, the second LC series resonant unit further includes a fourth inductor and a third varactor diode, the fourth inductor and the third varactor diode are connected in sequence, and the input terminal of the fourth inductor is connected to the coupling port of the quadrature coupler.
[0016] To better realize this utility model, the piezoelectric device further includes a piezoelectric transducer, and the input end of the piezoelectric transducer is connected to the phase modulation device through a third matching network.
[0017] To better realize this utility model, the antenna group further includes at least one receiving antenna and at least one transmitting antenna. The receiving antenna is connected to the frequency converter through a first matching network, and the transmitting antenna is connected to the phase modulation device through a fourth matching network.
[0018] A passive wireless vibration sensing system includes a read / write device, which is wirelessly connected to at least one passive wireless vibration sensing device.
[0019] Compared with the prior art, this utility model has the following advantages and beneficial effects:
[0020] (1) This utility model is completely passive, requiring no battery or wired power supply. The energy of the sensing device comes from the radio frequency energy sent by the reader and the energy generated by the vibration of the target under test. It is intrinsically safe, requires no wiring, and has low maintenance and repair costs.
[0021] (2) The phase adjustment device of this utility model can realize a large frequency shift change in voltage response, which can improve the sensing accuracy. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the architecture of a passive wireless vibration sensing device.
[0023] Figure 2 This is a schematic diagram of the specific structure of a passive wireless vibration sensing device.
[0024] Figure 3 This is a schematic diagram of the architecture of a passive wireless vibration sensing system.
[0025] Wherein: 1-antenna group; 11-receiving antenna; 12-transmitting antenna;
[0026] Frequency converter; 21-First inductor; 22-First varactor diode; 23-Second inductor; 24-First capacitor;
[0027] Phase adjustment device; 31-orthogonal coupler; 32-third inductor; 33-second varactor diode; 34-fourth inductor; 35-third varactor diode;
[0028] Piezoelectric device; 41-Piezoelectric transducer;
[0029] Read / write device; 6-first matching network; 7-second matching network; 8-third matching network; 9-fourth matching network. Detailed Implementation
[0030] Example 1:
[0031] This embodiment provides a passive wireless vibration sensing device, such as... Figure 1As shown, it includes an antenna group 1, which includes at least one antenna. The receiving end is connected to a frequency converter 2, and the transmitting end is connected to a phase modulation device 3. The frequency converter 2 is connected to the phase modulation device 3, and the phase modulation device 3 is connected to a piezoelectric device 4.
[0032] Antenna group 1 is used to receive wireless radio frequency signals and transmit radio frequency signals with frequency f1 to frequency converter 2;
[0033] The frequency converter 2 is used to convert a radio frequency signal with frequency f1 into a radio frequency signal with frequency f2 through passive mixing, and satisfies: f2=f1±n×fr, where: fr represents the center frequency of the frequency selection unit in the frequency converter; n represents the frequency selection level.
[0034] The piezoelectric device 4 is used to detect vibrations in the external environment in the absence of a passive signal, convert the vibrations into a corresponding voltage, and transmit the voltage to the phase modulation device 3.
[0035] The phase modulation device 3 modulates the phase of the radio frequency signal with frequency f2 according to the received voltage, and sends the phase-modulated radio frequency signal with frequency f2 to the antenna group 1, which then transmits the radio frequency signal to free space.
[0036] A passive wireless vibration sensing system, such as Figure 3 As shown, it includes a read / write device 5, which is wirelessly connected to at least one passive wireless vibration sensor.
[0037] The reading and writing device 5 sends radio frequency signals at frequency f1 and receives signals at frequency f2 to the passive wireless vibration sensing device; by demodulating the radio frequency signal at frequency f2, vibration sensing values, including vibration amplitude and vibration acceleration, can be obtained.
[0038] Example 2:
[0039] This embodiment is a further optimization based on Embodiment 1, such as... Figure 2 As shown, the frequency converter 2 includes a first inductor 21, a first varactor diode 22, and an LC parallel resonant unit. The first inductor 21 and the first varactor diode 22 are connected in series. The input terminal of the first inductor 21 is connected to the receiving terminal of the antenna group 1, and the output terminal of the first varactor diode 22 is connected to the input terminals of the LC parallel resonant unit and the phase modulation device 3, respectively. The LC parallel resonant unit includes a second inductor 23 and a first capacitor 24. The input terminal of the second inductor 23 and the input terminal of the first capacitor 24 are connected in parallel and then connected to the output terminal of the first varactor diode 22.
[0040] The resonant frequency of the LC parallel resonant unit is fr. The receiving antenna 11 of the antenna group 1 is connected to the input terminal of the first inductor 21 through the first matching network 6, and the output terminal of the first varactor diode 22 is connected to the phase modulation device 3 through the second matching network 7. The second matching network 7 is configured to impedance match the RF signal at frequency f2 and to mismatch the RF signal at frequency f1.
[0041] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again.
[0042] Example 3:
[0043] This embodiment is a further optimization based on the above embodiment 1 or 2, such as... Figure 2 As shown, the phase modulation device 3 includes an orthogonal coupler 31, a first LC series resonant unit, and a second LC series resonant unit. The input port of the orthogonal coupler 31 is connected to the output terminal of the frequency converter 2 through a second matching network 7. The through port of the orthogonal coupler 31 is connected to the first LC series resonant unit. The coupling port of the orthogonal coupler 31 is connected to the second LC series resonant unit. The isolation port of the orthogonal coupler 31 is connected to the transmitting antenna 12 of the antenna group 1 through a fourth matching network 9.
[0044] By employing an orthogonal coupler 31 and a first LC series resonant unit and a second LC series resonant unit with the same structure, a phase modulation module is formed, which has the characteristics of a large voltage-frequency shift range. This can improve the phase change of the radio frequency signal at frequency f2, thereby helping to demodulate the vibration of the target under test applied to the radio frequency signal at frequency f2, thus improving the vibration monitoring accuracy.
[0045] Furthermore, the orthogonal coupler 31 includes four branch line units with quarter-wavelength structures respectively corresponding to the input port, through port, coupling port, and isolation port.
[0046] Furthermore, the branch line unit of the corresponding isolation port is connected to the second LC series resonant unit and the piezoelectric device 4, respectively.
[0047] Furthermore, the first LC series resonant unit includes a third inductor 32 and a second varactor diode 33, the third inductor 32 and the second varactor diode 33 are connected in series, and the input terminal of the third inductor 32 is connected to the through port of the quadrature coupler 31.
[0048] Furthermore, the second LC series resonant unit includes a fourth inductor 34 and a third varactor diode 35, which are connected in sequence. The input terminal of the fourth inductor 34 is connected to the coupling port of the quadrature coupler 31.
[0049] The other parts of this embodiment are the same as those in Embodiment 1 or 2 above, so they will not be described again.
[0050] Example 4:
[0051] This embodiment is a further optimization based on any one of embodiments 1-3 above, such as... Figure 2 As shown, the piezoelectric device 4 includes a piezoelectric transducer 41. The input end of the piezoelectric transducer 41 is connected to the phase modulation device 3 through a third matching network 8. The third matching network 8 is used to achieve impedance matching between the piezoelectric transducer 41 and the phase modulation device 3.
[0052] The other parts of this embodiment are the same as any one of the embodiments 1-3 above, so they will not be described again.
[0053] Example 5:
[0054] This embodiment is a further optimization based on any one of embodiments 1-4 above, such as... Figure 2 As shown, the antenna group 1 includes a receiving antenna 11 and a transmitting antenna 12. The receiving antenna 11 is connected to the frequency converter 2 through a first matching network 6, and the transmitting antenna 12 is connected to the phase modulation device 3 through a fourth matching network 9.
[0055] The fourth matching network 9 provides impedance matching for the radio frequency signal with frequency f2 and impedance mismatch for the radio frequency signal with frequency f1. The radio frequency signal with frequency f2 carrying vibration sensing information is transmitted from the isolation port of the quadrature coupler 41 through the fourth matching network 9 to the transmitting antenna 12, and the transmitting antenna 12 then sends the radio frequency signal with frequency f2 into free space.
[0056] The other parts of this embodiment are the same as any one of the embodiments 1-4 above, so they will not be described again.
[0057] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present utility model shall fall within the protection scope of the present utility model.
Claims
1. A passive wireless vibration sensing device, characterized in that, It includes an antenna group (1), which includes at least one antenna. The antenna group is connected to a frequency converter (2) and a phase modulation device (3). The frequency converter (2) is connected to the phase modulation device (3), and the phase modulation device (3) is connected to a piezoelectric device (4). The antenna group (1) is used to receive wireless radio frequency signals and transmit radio frequency signals with frequency f1 to the frequency converter (2). The frequency converter (2) is used to convert a radio frequency signal with frequency f1 into a radio frequency signal with frequency f2 through passive mixing; The piezoelectric device (4) is used to detect the vibration of the external environment in the absence of a passive state, convert the vibration into a corresponding voltage, and transmit the voltage to the phase modulation device (3); the phase modulation device (3) changes the phase of the radio frequency signal with frequency f2 according to the received voltage, and sends the phase-modulated radio frequency signal with frequency f2 to the antenna group (1), and sends the radio frequency signal to free space through the antenna group (1).
2. The passive wireless vibration sensing device according to claim 1, characterized in that, The frequency converter (2) includes a first inductor (21), a first varactor diode (22), and an LC parallel resonant unit. The first inductor (21) and the first varactor diode (22) are connected in series. The input terminal of the first inductor (21) is connected to the receiving terminal of the antenna group (1), and the output terminal of the first varactor diode (22) is connected to the input terminal of the LC parallel resonant unit and the phase modulation device (3), respectively.
3. The passive wireless vibration sensing device according to claim 2, characterized in that, The LC parallel resonant unit includes a second inductor (23) and a first capacitor (24). The input terminal of the second inductor (23) is connected in parallel with the input terminal of the first capacitor (24) and then connected to the output terminal of the first varactor diode (22).
4. A passive wireless vibration sensing device according to any one of claims 1-3, characterized in that, The phase modulation device (3) includes an orthogonal coupler (31), a first LC series resonant unit, and a second LC series resonant unit. The input port of the orthogonal coupler (31) is connected to the output terminal of the frequency converter (2) through a second matching network (7). The through port of the orthogonal coupler (31) is connected to the first LC series resonant unit. The coupling port of the orthogonal coupler (31) is connected to the second LC series resonant unit. The isolation port of the orthogonal coupler (31) is connected to the transmitting end of the antenna group (1) through a fourth matching network (9).
5. A passive wireless vibration sensing device according to claim 4, characterized in that, The orthogonal coupler (31) includes four branch line units with quarter-wavelength structures respectively corresponding to the input port, through port, coupling port and isolation port.
6. A passive wireless vibration sensing device according to claim 5, characterized in that, The first LC series resonant unit includes a third inductor (32) and a second varactor diode (33). The third inductor (32) and the second varactor diode (33) are connected in series. The input terminal of the third inductor (32) is connected to the through port of the quadrature coupler (31).
7. A passive wireless vibration sensing device according to claim 5, characterized in that, The second LC series resonant unit includes a fourth inductor (34) and a third varactor diode (35). The fourth inductor (34) and the third varactor diode (35) are connected in sequence. The input terminal of the fourth inductor (34) is connected to the coupling port of the quadrature coupler (31).
8. A passive wireless vibration sensing device according to any one of claims 1-3, characterized in that, The piezoelectric device (4) includes a piezoelectric transducer (41), the input of which is connected to the phase modulation device (3) via a third matching network (8).
9. A passive wireless vibration sensing device according to any one of claims 1-3, characterized in that, The antenna group (1) includes at least one receiving antenna (11) and at least one transmitting antenna (12). The receiving antenna (11) is connected to the frequency converter (2) through a first matching network (6), and the transmitting antenna (12) is connected to the phase modulation device (3) through a fourth matching network (9).
10. A passive wireless vibration sensing system, characterized in that, It includes a read / write device (5) that is wirelessly connected to at least one passive wireless vibration sensing device according to any one of claims 1-9.