CN209946189U - Gear tooth type liquid metal rotation speed sensor - Google Patents
Gear tooth type liquid metal rotation speed sensor Download PDFInfo
- Publication number
- CN209946189U CN209946189U CN201920783921.8U CN201920783921U CN209946189U CN 209946189 U CN209946189 U CN 209946189U CN 201920783921 U CN201920783921 U CN 201920783921U CN 209946189 U CN209946189 U CN 209946189U
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- liquid metal
- tooth type
- cavity
- speed sensor
- gear tooth
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- 229910001338 liquidmetal Inorganic materials 0.000 title claims abstract description 85
- 238000007789 sealing Methods 0.000 claims description 14
- 230000006698 induction Effects 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 10
- 239000000523 sample Substances 0.000 claims description 10
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims description 4
- 229910000846 In alloy Inorganic materials 0.000 claims description 4
- 229910001128 Sn alloy Inorganic materials 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 229910052733 gallium Inorganic materials 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- 230000002209 hydrophobic effect Effects 0.000 claims description 3
- RHZWSUVWRRXEJF-UHFFFAOYSA-N indium tin Chemical compound [In].[Sn] RHZWSUVWRRXEJF-UHFFFAOYSA-N 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 8
- 230000017525 heat dissipation Effects 0.000 abstract description 5
- 238000005461 lubrication Methods 0.000 abstract description 2
- 238000012360 testing method Methods 0.000 description 7
- 238000009434 installation Methods 0.000 description 6
- 238000013461 design Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 239000000428 dust Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000001050 lubricating effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 239000012811 non-conductive material Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000004020 conductor Substances 0.000 description 1
- 238000010892 electric spark Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
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Abstract
The utility model discloses a gear tooth type liquid metal revolution speed sensor, include: a closed cavity; the connecting shaft is rotatably arranged on one end surface of the cavity and penetrates into the cavity; the connecting shaft has conductivity; the gear tooth type rotor is fixed on the connecting shaft and is positioned in the cavity, the tooth tops of the gear teeth of the gear tooth type rotor are conductive, the tooth roots of the gear teeth are nonconductive, and a part of the gear teeth are immersed in the liquid metal; and the electric signal receiving assembly penetrates into the cavity from the outside and is electrically connected with the liquid metal. When the gear tooth type liquid metal rotating speed sensor of the utility model is used for measuring speed, the resistance only comes from liquid metal, and compared with the traditional rotating speed sensor with pure mechanical structure, the resistance is very small; meanwhile, the liquid metal has good heat dissipation and lubrication performance and can adapt to rotating speed measurement under the condition of high-speed rotation.
Description
Technical Field
The utility model relates to a speed sensor field especially relates to a tooth-like liquid metal speed sensor of wheel.
Background
A rotation speed sensor is a sensor that converts the rotation speed of a rotating object into an electrical output. The existing rotating speed sensor mainly carries out rotating speed measurement by directly transmitting a rotating state through a mechanical structure, but in the testing method, the testing sensor can generate a certain amount of load and resistance to a speed measuring shaft, and the phenomenon is particularly obvious in an electromechanical system. In addition, the bearing bush of the test sensor is easy to generate heat when continuously rubbed in an electrified state, and even can generate electric sparks after being worn, so that the performance of the electric connector is seriously influenced, and dangerous accidents are caused.
Accordingly, the prior art is yet to be improved and developed.
SUMMERY OF THE UTILITY MODEL
In view of the above-mentioned prior art not enough, the utility model aims at providing a tooth-like liquid metal revolution speed sensor of wheel aims at solving the current poor problem of mechanical structure formula revolution speed sensor reliability.
The technical scheme of the utility model as follows:
a gear tooth type liquid metal rotation speed sensor, comprising:
a closed cavity;
the liquid metal is arranged in the cavity;
the connecting shaft is rotatably arranged on one end face of the cavity and penetrates into the cavity; the connecting shaft has conductivity;
the gear tooth type rotor is fixed on the connecting shaft and is positioned in the cavity, the tooth tops of the gear teeth of the gear tooth type rotor are conductive, the tooth roots of the gear teeth are nonconductive, and a part of the gear teeth are immersed in the liquid metal;
the electric signal receiving assembly penetrates into the cavity from the outside and is electrically connected with the liquid metal;
external current is input by the connecting shaft, is transmitted to the gear tooth type rotor through the connecting shaft, then flows through the liquid metal, and finally flows out of the electric signal receiving assembly.
The gear tooth type liquid metal rotating speed sensor is characterized in that gear teeth of the gear tooth type rotor are in a bevel gear structure.
The gear tooth type liquid metal rotating speed sensor is characterized in that gear teeth of the gear tooth type rotor are in symmetrical tooth shapes.
The gear tooth type liquid metal rotating speed sensor is characterized in that the liquid metal is gallium-indium alloy or gallium-indium-tin alloy.
The tooth formula liquid metal rotational speed sensor of wheel, wherein, the signal of telecommunication receiving assembly includes:
an induction electrode electrically connected to the liquid metal;
the signal receiver is electrically connected with the sensing electrode and is used for receiving and processing the current pulse sensed by the sensing electrode;
and the output terminal is electrically connected with the signal receiver and is used for outputting the signal received by the signal receiver.
The gear tooth type liquid metal rotating speed sensor is characterized in that a thrust bearing is fixed at the bottom of the cavity, and the connecting shaft is abutted to the thrust bearing.
The gear tooth type liquid metal rotation speed sensor is characterized in that the cavity comprises a base with one end provided with a containing cavity and a sealing end cover used for sealing the containing cavity, a shaft mounting hole is formed in the sealing end cover, and the connecting shaft is rotatably mounted in the shaft mounting hole.
The gear tooth type liquid metal rotating speed sensor is characterized in that a through hole communicated with the containing cavity is further formed in the top of the base, and a probe used for measuring the liquid level of liquid metal is arranged at the through hole.
The gear tooth type liquid metal rotating speed sensor is characterized in that an annular groove surrounding the connecting shaft is formed in one inward side of the sealing end cover, and an O-shaped ring used for sealing the accommodating cavity is arranged in the annular groove.
The gear tooth type liquid metal rotating speed sensor is characterized in that a hydrophobic coating is modified on the surface of the O-shaped ring.
Has the advantages that: the utility model provides a gear tooth type liquid metal revolution speed transducer, when measuring the speed, the resistance of the gear tooth type liquid metal revolution speed transducer only comes from the liquid metal, compared with the traditional revolution speed transducer with pure mechanical structure, the resistance is very small; meanwhile, the liquid metal has good heat dissipation and lubricating properties, can be applied to extreme environments such as dust, underwater and the like, can adapt to rotating speed measurement under the condition of high-speed rotation, greatly improves the response speed and stability of the rotating speed sensor, and greatly improves the response speed and stability of the rotating speed sensor.
Drawings
Fig. 1 is an assembly diagram of a gear tooth type liquid metal revolution speed sensor according to a preferred embodiment of the present invention.
Fig. 2 is an exploded view of fig. 1.
Fig. 3 is a partial cross-sectional view of fig. 1.
Fig. 4 is a diagram of an embodiment of an electrical signal receiving assembly according to the present invention.
Fig. 5 is a diagram illustrating an embodiment of the present invention in which a thrust bearing is provided to the gear teeth type liquid metal rotation speed sensor.
Fig. 6 is a diagram of an embodiment of the present invention in which the gear teeth type liquid metal rotation speed sensor is provided with an O-ring.
Fig. 7 is a projection view from the end cap of fig. 1 in the axial direction.
Fig. 8 is a sectional view taken along line a-a of fig. 7.
Fig. 9 is an enlarged view of a portion B in fig. 8.
Detailed Description
The utility model provides a gear tooth type liquid metal revolution speed transducer, for making the utility model discloses a purpose, technical scheme and effect are clearer, more clear and definite, it is following right the utility model discloses further detailed description. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It should be noted that in the description of the present invention, the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Simultaneously the utility model discloses in, "electrically conductive" processing mode has: directly selecting a conductor material or manufacturing a conductive coating on a non-conductive material; "non-conductive" may also be treated similarly in accordance with this principle.
The utility model provides a tooth-like liquid metal revolution speed sensor's of wheel preferred embodiment, as shown in fig. 1, fig. 2 and fig. 3, including base 1, end cover 2, liquid metal, the tooth-like rotor 3 of wheel and signal of telecommunication receiving assembly 4, base 1 and the equipment of end cover 2 constitute inclosed cavity. The shape of the base 1 is not limited, and in the figure, a cylindrical base is taken as an example, one end of the base 1 is provided with an accommodating cavity 11, and the other end can be provided with a flange 12 according to actual needs. The sealing end cover 2 is arranged at the opening of the accommodating cavity 11 and seals the accommodating cavity 11. The liquid metal and the geared rotor 3 are sealed in the accommodating cavity 11, wherein the liquid metal can be gallium indium alloy or gallium indium tin alloy. The end cap 2 is provided with a shaft mounting hole 21, the geared rotor 3 is connected to the shaft mounting hole 21 through a connecting shaft 31 and is rotatable with respect to the end cap 2, and the connecting shaft 31 is electrically conductive. The tooth tips of the teeth of the tooth rotor 3 are electrically conductive, the tooth roots are electrically non-conductive and a part of the teeth are immersed in the liquid metal. The top of the base 1 is also provided with a groove 13 communicated with the accommodating cavity 11, and the electric signal receiving assembly 4 is arranged in the groove 13 and is electrically connected with the liquid metal in the accommodating cavity 11.
The utility model discloses a gear tooth formula liquid metal revolution speed sensor's theory of operation does: external current is input through the connecting shaft 31, the current is transmitted to the gear tooth type rotor 3 through the connecting shaft 31, then flows through liquid metal, and finally flows out of the electric signal receiving assembly 4; the mechanical rotation of the device to be tested is transmitted to the gear tooth type rotor 3 through the connecting shaft 31, the gear tooth type rotor 3 has the difference that the tooth tops of gear teeth are conductive and the tooth bottoms of the gear teeth are non-conductive, in the rotation process of the gear tooth type rotor 3, a current signal output by an internal circuit is a pulse signal, and the pulse frequency is related to the number of the gear teeth of the gear tooth type rotor 3. The number of the pulse signals in a certain time is divided by the number of the teeth of the gear tooth type rotor 3 to obtain the number of the rotation turns in the time, and then the rotation speed is obtained by dividing the time. When the gear tooth type liquid metal rotating speed sensor of the utility model is used for measuring speed, the resistance only comes from liquid metal, and compared with the traditional rotating speed sensor with pure mechanical structure, the resistance is very small; meanwhile, the liquid metal has good heat dissipation and lubricating properties, can be applied to extreme environments such as dust, underwater and the like, and greatly improves the response speed and stability of the rotating speed sensor.
The utility model provides a concrete structure of signal of telecommunication receiving assembly 4, as shown in fig. 3, fig. 4 and fig. 5, including induction electrode 41, signal receiver 42 and the output terminal 43 that connects gradually the electricity, induction electrode 41 is deepened to holding in the chamber 11 from the bottom of recess 13 to submergence is like liquid metal, and the signal of telecommunication flows to induction electrode 41 from liquid metal, then conducts to signal receiver 42, and signal receiver 42 conducts the current pulse who senses for output terminal 43, and by output terminal 43 with signal output. Preferably, the distance from the end of the induction electrode to the addendum circle of the cogged rotor 3 is between 50 μm and 2000 μm, and the specific size needs to be determined according to the specific rotating speed, and the higher the rotating speed, the smaller the value is required. It is emphasized that the sensor has no special requirement on the length dimension of the sensing area, can be made with very small precision without any influence, and the dimension of the sensor cavity can be less than 50 μm under the condition that the manufacturing process meets.
The utility model discloses a gear tooth formula rotor 3 can adopt ordinary cylindrical gear, but the unable direct adjustment addendum of cylindrical gear and the interval between the signal of telecommunication receiving assembly 4 (or induction electrode 41), this interval has just been confirmed after the processing is accomplished, and this interval is influential to pulse signal's size, the sensitivity of sensor, for key parameter. Therefore, it is preferable to use a bevel gear (or bevel gear), and when adjustment is required, the distance can be adjusted by moving the position of the bevel gear on the connecting shaft 31 by adding a spacer, or a sleeve. The teeth of the tooth rotor 3 may be symmetrical tooth profiles or asymmetrical tooth profiles, preferably symmetrical tooth profiles, and the specific shape may be an involute tooth profile, a rectangular tooth profile, a trapezoidal tooth profile, and the like.
In order to prevent the geared rotor 3 from rubbing against the bottom of the accommodating chamber 11 during rotation, a thrust bearing 5 may be provided at the bottom of the accommodating chamber 11, and the connecting shaft 31 abuts against the thrust bearing 5, as shown in fig. 2 and 4, and both may rotate in synchronization.
The utility model discloses can also set up a probe 6 that is used for monitoring the liquid level of liquid metal, specifically as shown in fig. 2, fig. 3, set up a through-hole 14 at the top of base 1, through-hole 14 with hold chamber 11 intercommunication, probe 6 fixes in through-hole 14 to inwards stretch out certain length, be used for surveying the liquid level of liquid metal. In addition, the through hole 14 can also be used for replenishing liquid metal to achieve the aim of adjusting the liquid level. The probe 6 needs to be made of a non-conductive material, the lower end of the probe 6 should be lower than the tooth pitch circle (or the central circle of a rectangular ruler) of the tooth type rotor 3, and the standard scale should be higher than the tooth addendum circle of the tooth type rotor 3. When the liquid level position of the liquid metal is detected, the sensor is required to be kept still for a period of time, so that the liquid metal can fully flow back from the cavity wall of the accommodating cavity 11, and the measurement error is reduced.
In order to improve the overall sealing performance and prevent liquid metal leakage, an O-shaped ring 7 can be added for sealing. Specifically, as shown in fig. 6, an annular groove 22 surrounding the connecting shaft 31 is provided on the inward side of the end cap 2, and the O-ring 7 is disposed in the annular groove 22. Preferably, the hydrophobic coating is modified on the surface of the O-shaped ring, so that a better leakage-proof effect can be achieved.
In the above embodiments of the present invention, the specific connection mode of the electric signal receiving assembly 4 and the probe 6 for monitoring the liquid level of the liquid metal can refer to fig. 7, fig. 8 and fig. 9.
Based on the utility model discloses a gear tooth formula liquid metal revolution speed sensor, the utility model also provides a revolution speed measurement method. Specifically, the rotating assembly to be tested is connected with the connecting shaft 31, after the rotating assembly to be tested is started, the rotation of the rotating assembly to be tested is transmitted to the wheel tooth type rotor 3 through the connecting shaft 31, in the rotating process of the wheel tooth type rotor 3, the current input from the end of the connecting shaft 31 is changed into pulse current and is output from the receiving assembly 4, the rotating speed R of the rotating assembly to be tested can be calculated through the following formula,
R=N/( n×T)，
and N is the number of pulse signals received by the electric signal receiving assembly in a time period T, and N is the number of gear teeth of the gear tooth type rotor.
The utility model discloses a multiple factor need be considered when the design preparation to the tooth-like liquid metal revolution speed sensor of wheel, the utility model provides a design preparation embodiment, including following step:
and S1, selecting gallium-indium alloy or gallium-indium-tin alloy manufactured in different proportions according to the temperature condition of the use environment and the heat dissipation of the sensor, and carrying out a viscous resistance test under the condition of a test circuit.
S2, designing the tooth number N of the induction electrode and the gear tooth type rotor according to the condition of the speed measurement input end and the rotating speed measurement requirement.
S3, designing a sensor shell according to the installation environment and the position size, installing an induction electrode on the inner surface of the sensor shell, adjusting the actual effective gap of the cavity of the accommodating cavity through the thickness of the O-shaped ring, designing the modulus of the gear tooth type rotor and the extension length of the induction electrode according to the installation position and the rotating speed measurement requirement, further determining the diameter of the speed measuring rotor, and selecting the type of the thrust bearing, thereby determining the inner surface size of the base according to the allowable cavity gap size.
And S4, designing a liquid metal liquid level probe according to the installation position of the induction electrode and the distance from the extension length to the addendum circle of the gear-type rotor.
S5, designing a sensor base according to the installation environment and the position size, sequentially installing an induction electrode, a signal receiver, a thrust bearing, a gear tooth type rotor and a liquid metal liquid level probe on the sensor base, and checking whether mutual interference exists.
S6, designing an end cover according to the size of the sensor base, designing an end cover O-shaped sealing ring installation groove on the end cover, filling the prepared liquid metal into the speed measuring cavity through the installation hole of the liquid metal liquid level probe, and testing the anti-leakage characteristic of the speed measuring cavity.
And S7, after initial assembly, performing an electrification test experiment to ensure the effectiveness of the assembly.
In step S1, the viscous resistance of the liquid metal in the charged state, the disturbance of the resistance value, and the wettability of the liquid metal to the electrode material need to be considered when selecting the liquid metal.
To sum up, the utility model provides a wheel tooth type liquid metal revolution speed sensor, when the wheel tooth type liquid metal revolution speed sensor of the utility model is used for measuring the speed, the resistance only comes from the liquid metal, and compared with the traditional revolution speed sensor with a pure mechanical structure, the resistance is very small; meanwhile, the liquid metal has good heat dissipation and lubrication performance, can be applied to extreme environments such as dust, underwater and the like, can adapt to rotating speed measurement under the condition of high-speed rotation, greatly improves the response speed and stability of the rotating speed sensor, and greatly improves the response speed and stability of the rotating speed sensor; the sensor has simple structure, compact design, relative independence of all parts, good interchangeability and capability of realizing modularization, serialization and rapid design; the maintenance and overhaul are convenient; the sensor has no special requirement on the length size of a sensing area, can be made very small, and the gap of a sensor cavity can be smaller than 50 mu m.
It is to be understood that the invention is not limited to the above-described embodiments, and that modifications and variations may be made by those skilled in the art in light of the above teachings, and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.
Claims (10)
1. A gear tooth type liquid metal rotation speed sensor is characterized by comprising:
a closed cavity;
the liquid metal is arranged in the cavity;
the connecting shaft is rotatably arranged on one end face of the cavity and penetrates into the cavity; the connecting shaft has conductivity;
the gear tooth type rotor is fixed on the connecting shaft and is positioned in the cavity, the tooth tops of the gear teeth of the gear tooth type rotor are conductive, the tooth roots of the gear teeth are nonconductive, and a part of the gear teeth are immersed in the liquid metal;
the electric signal receiving assembly penetrates into the cavity from the outside and is electrically connected with the liquid metal;
external current is input by the connecting shaft, is transmitted to the gear tooth type rotor through the connecting shaft, then flows through the liquid metal, and finally flows out of the electric signal receiving assembly.
2. The gear tooth type liquid metal rotation speed sensor according to claim 1, wherein gear teeth of the gear tooth type rotor adopt a bevel gear structure.
3. A gear tooth type liquid metal rotation speed sensor according to claim 1, wherein the gear teeth of the gear tooth type rotor are of symmetrical tooth shape.
4. The gear tooth type liquid metal rotating speed sensor according to claim 1, wherein the liquid metal is gallium indium alloy or gallium indium tin alloy.
5. A wheel tooth liquid metal rotational speed sensor according to claim 1, wherein said electrical signal receiving assembly comprises:
an induction electrode electrically connected to the liquid metal;
the signal receiver is electrically connected with the sensing electrode and is used for receiving and processing the current pulse sensed by the sensing electrode;
and the output terminal is electrically connected with the signal receiver and is used for outputting the signal received by the signal receiver.
6. The gear tooth type liquid metal rotation speed sensor according to claim 1, wherein a thrust bearing is fixed to the bottom of the cavity, and the connecting shaft abuts against the thrust bearing.
7. The gear tooth type liquid metal rotation speed sensor according to claim 1, wherein the cavity comprises a base with a containing cavity at one end, and a sealing end cover for sealing the containing cavity, the sealing end cover is provided with a shaft mounting hole, and the connecting shaft is rotatably mounted in the shaft mounting hole.
8. The gear tooth type liquid metal rotation speed sensor according to claim 7, wherein a through hole communicated with the accommodating cavity is further formed in the top of the base, and a probe for measuring the liquid level of the liquid metal is arranged at the through hole.
9. A gear tooth type liquid metal rotating speed sensor according to claim 7, wherein an annular groove surrounding the connecting shaft is formed in the inward side of the sealing end cover, and an O-shaped ring for sealing the accommodating cavity is arranged in the annular groove.
10. The gear tooth type liquid metal rotation speed sensor according to claim 9, wherein a hydrophobic coating is modified on the surface of the O-ring.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920783921.8U CN209946189U (en) | 2019-05-28 | 2019-05-28 | Gear tooth type liquid metal rotation speed sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920783921.8U CN209946189U (en) | 2019-05-28 | 2019-05-28 | Gear tooth type liquid metal rotation speed sensor |
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| Publication Number | Publication Date |
|---|---|
| CN209946189U true CN209946189U (en) | 2020-01-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201920783921.8U Expired - Fee Related CN209946189U (en) | 2019-05-28 | 2019-05-28 | Gear tooth type liquid metal rotation speed sensor |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110208564A (en) * | 2019-05-28 | 2019-09-06 | 南方科技大学 | A kind of gear tooth-type liquid metal speed probe and rotating speed measurement method |
-
2019
- 2019-05-28 CN CN201920783921.8U patent/CN209946189U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110208564A (en) * | 2019-05-28 | 2019-09-06 | 南方科技大学 | A kind of gear tooth-type liquid metal speed probe and rotating speed measurement method |
| CN110208564B (en) * | 2019-05-28 | 2024-04-02 | 南方科技大学 | Gear tooth type liquid metal rotating speed sensor and rotating speed measuring method |
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