阅读说明：本技术 一种电涡流传感器探头及电涡流传感器 (Eddy current sensor probe and eddy current sensor ) 是由 房高超 张华东 孙广庆 张富春 孙鹏 刘士方 刘银才 张敬 何大可 邵帅 于 2021-09-01 设计创作，主要内容包括：本发明公开了一种电涡流传感器探头及电涡流传感器,其中,电涡流传感器探头包括探头主体、至少一个突出体及至少一个位置监测线圈。电涡流传感器包括电涡流传感器探头、传输屏蔽信号线和前置器。本发明通过在电涡流传感器的探头主体的后端设置均匀分布的至少一个突出体,并将位置监测线圈及外围电路对应放置在突出体的内部,用以测量位置监测线圈与被监测物体的外壳的距离,实现了电涡流传感器对自身探头位置的监测,从而保证探头一直在正确的位置上监测设备,进而保证了电涡流传感器对设备位移监测的准确性。(The invention discloses an eddy current sensor probe and an eddy current sensor, wherein the eddy current sensor probe comprises a probe main body, at least one protrusion and at least one position monitoring coil. The electric eddy current sensor comprises an electric eddy current sensor probe, a transmission shielding signal wire and a front-end device. According to the invention, the rear end of the probe main body of the eddy current sensor is provided with the at least one protrusion body which is uniformly distributed, the position monitoring coil and the peripheral circuit are correspondingly placed in the protrusion body to measure the distance between the position monitoring coil and the shell of the monitored object, so that the monitoring of the eddy current sensor on the position of the probe of the eddy current sensor is realized, the probe is ensured to monitor equipment at the correct position all the time, and the accuracy of the eddy current sensor on equipment displacement monitoring is further ensured.)

1. An eddy current sensor probe, comprising:

the front end of the probe main body penetrates through the shell of the monitored object and extends into the monitored object, and the probe main body is used for monitoring the distance between the front end of the probe main body and the inner core of the monitored object to obtain an equipment position monitoring signal;

at least one protrusion evenly distributed at the rear end of the probe body;

the position monitoring coil is used for monitoring the distance between the position monitoring coil and the shell of the monitored object to obtain a corresponding relative position monitoring signal;

the number of the position monitoring coils is equal to that of the protrusions; a gap exists inside the protrusion body as a first gap; the first gap is used for storing the position monitoring coil and the peripheral circuit.

2. The eddy current sensor probe of claim 1, further comprising:

at least one supporting body respectively embedded in the protrusions and positioned between the position monitoring coil and the probe body for supporting and protecting the position monitoring coil; the supporting bodies and the protrusions are equal in number and correspond to each other one by one.

3. The eddy current sensor probe according to claim 1, wherein the probe body comprises:

a front end housing penetrating through a shell of the monitored object and extending into the monitored object;

the rear end shell is connected with the front end shell and used for adjusting the length of the front end shell extending into the monitored object; the protrusions are uniformly distributed on the periphery of the rear-end shell;

and the equipment monitoring coil is positioned in the front end shell and used for monitoring the distance between the equipment monitoring coil and the inner core of the monitored object to obtain an equipment position monitoring signal.

4. The eddy current sensor probe according to claim 3, wherein a gap exists as a second gap inside the front end housing; the second gap is used for storing the equipment monitoring coil and the peripheral circuit.

5. The eddy current sensor probe according to claim 4, wherein a gap exists inside the rear end housing as a third gap; the third gap is respectively communicated with the first gap and the second gap.

6. An eddy current sensor, comprising an eddy current sensor probe according to any one of claims 1-5 and a transmission shield signal line and a pre-stage;

the transmission shielding signal wire is respectively connected with an equipment monitoring coil positioned on the probe main body and a position monitoring coil positioned on the protrusion body;

the pre-positioning device is connected with the transmission shielding signal wire and is used for respectively providing high-frequency oscillation current for generating an eddy current effect for the equipment monitoring coil and the position monitoring coil;

the front-end device is also used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

7. The eddy current sensor according to claim 6, further comprising a cable plug; the transmission shielding signal line is connected with the front-end connector through the cable plug.

8. The eddy current sensor according to claim 6, wherein the transmission shielded signal line is composed of a plurality of coaxial cables; the number of the coaxial cables is equal to the total number of the equipment monitoring coils and the position monitoring coils; the plurality of coaxial cables are connected with the equipment monitoring coil, the position monitoring coil and the pre-positioning device respectively.

9. The eddy current sensor according to claim 6, wherein the pre-positioner comprises:

the oscillator is connected with the transmission shielding signal wire and used for respectively providing high-frequency oscillation current for generating an eddy current effect for the equipment monitoring coil and the position monitoring coil;

and the controller is connected with the transmission shielding signal wire and used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

10. The eddy current sensor according to claim 9, further comprising:

the alarm is connected with the controller and used for sending out an alarm according to the prompt signal; the prompt signal is generated by the controller when the probe of the eddy current sensor displaces.

Technical Field

The invention relates to the field of sensing devices, in particular to an eddy current sensor probe and an eddy current sensor.

Background

The current monitoring of the power plant on the running state of the equipment is mainly to monitor the temperature and the vibration of the equipment through a sensor. Most of vibration monitoring adopts an eddy current sensor, and the eddy current sensor monitors the vibration of an object by measuring displacement. In the complex environment of a power plant, a traditional eddy current sensor has a high possibility of generating errors under the condition that related personnel do not know, so that the whole system judges the state of equipment.

In the prior art, the eddy current sensor is generally mounted by adopting bonding or screw mounting, and the two mounting modes are easy to loosen and even fall off in a complex environment of a power plant.

When the sensor is loose, the displacement measured by the sensor changes, which causes the system to make wrong judgment on the running state of the equipment, and if relevant personnel do not find the sensor to be loose in time, unnecessary shutdown may be caused, which affects production.

When the sensor drops, the system of the power plant can give an alarm to prompt, the equipment is in a state of not being monitored at the moment, safety accidents are easy to occur, if the equipment is important, the equipment needs to be stopped to reinstall the sensor, and great influence is also caused on production.

Disclosure of Invention

The invention aims to provide an eddy current sensor probe and an eddy current sensor, which can monitor the position of the probe and ensure that the probe always monitors equipment at a correct position, thereby ensuring the accuracy of equipment displacement monitoring.

In order to achieve the purpose, the invention provides the following scheme:

an eddy current sensor probe, comprising:

the front end of the probe main body penetrates through the shell of the monitored object and extends into the monitored object, and the probe main body is used for monitoring the distance between the front end of the probe main body and the inner core of the monitored object to obtain an equipment position monitoring signal;

at least one protrusion evenly distributed at the rear end of the probe body;

the position monitoring coil is used for monitoring the distance between the position monitoring coil and the shell of the monitored object to obtain a corresponding relative position monitoring signal;

the number of the position monitoring coils is equal to that of the protrusions; a gap exists inside the protrusion body as a first gap; the first gap is used for storing the position monitoring coil and the peripheral circuit.

Optionally, the eddy current sensor probe further comprises:

at least one supporting body respectively embedded in the protrusions and positioned between the position monitoring coil and the probe body for supporting and protecting the position monitoring coil; the supporting bodies and the protrusions are equal in number and correspond to each other one by one.

Optionally, the probe body comprises:

a front end housing penetrating through a shell of the monitored object and extending into the monitored object;

the rear end shell is connected with the front end shell and used for adjusting the length of the front end shell extending into the monitored object; the protrusions are uniformly distributed on the periphery of the rear-end shell;

and the equipment monitoring coil is positioned in the front end shell and used for monitoring the distance between the equipment monitoring coil and the inner core of the monitored object to obtain an equipment position monitoring signal.

Optionally, there is a gap inside the front end housing as a second gap; the second gap is used for storing the equipment monitoring coil and the peripheral circuit.

Optionally, a gap exists inside the rear end housing as a third gap; the third gap is respectively communicated with the first gap and the second gap.

The invention also provides an eddy current sensor which comprises the eddy current sensor probe, a transmission shielding signal wire and a prepositioner;

the transmission shielding signal wire is respectively connected with an equipment monitoring coil positioned on the probe main body and a position monitoring coil positioned on the protrusion body;

the pre-positioning device is connected with the transmission shielding signal wire and is used for respectively providing high-frequency oscillation current for generating an eddy current effect for the equipment monitoring coil and the position monitoring coil;

the front-end device is also used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

Optionally, the eddy current sensor further comprises a cable plug; the transmission shielding signal line is connected with the front-end connector through the cable plug.

Optionally, the transmission shielding signal line is composed of a plurality of coaxial cables; the number of the coaxial cables is equal to the total number of the equipment monitoring coils and the position monitoring coils; the plurality of coaxial cables are connected with the equipment monitoring coil, the position monitoring coil and the pre-positioning device respectively.

Optionally, the pre-stage comprises:

the oscillator is connected with the transmission shielding signal wire and used for respectively providing high-frequency oscillation current for generating an eddy current effect for the equipment monitoring coil and the position monitoring coil;

and the controller is connected with the transmission shielding signal wire and used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

Optionally, the eddy current sensor further comprises:

the alarm is connected with the controller and used for sending out an alarm according to the prompt signal; the prompt signal is generated by the controller when the probe of the eddy current sensor displaces.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

the invention provides an eddy current sensor probe and an eddy current sensor, wherein the eddy current sensor probe comprises a probe main body, at least one protrusion and at least one position monitoring coil. The electric eddy current sensor comprises an electric eddy current sensor probe, a transmission shielding signal wire and a front-end device. According to the invention, the rear end of the probe main body of the eddy current sensor is provided with the at least one protrusion body which is uniformly distributed, the position monitoring coil and the peripheral circuit are correspondingly placed in the protrusion body to measure the distance between the position monitoring coil and the shell of the monitored object, so that the monitoring of the eddy current sensor on the position of the probe of the eddy current sensor is realized, the probe is ensured to monitor equipment at the correct position all the time, and the accuracy of the eddy current sensor on equipment displacement monitoring is further ensured.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a perspective view of an eddy current sensor provided in accordance with the present invention;

FIG. 2 is a top view of an eddy current sensor probe according to the present invention;

fig. 3 is a schematic diagram of an operating principle of an eddy current sensor according to the present invention.

Description of the symbols:

the device comprises a device monitoring coil-1, a front end shell-2, a second gap-3, a rear end shell-4, a support body-5, a first position monitoring coil-6, a second position monitoring coil-7, a third gap-8, a transmission shielding signal wire-9 and a cable plug-10.

Detailed Description

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 only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide an eddy current sensor probe and an eddy current sensor, which can monitor the position of the probe and ensure that the probe always monitors equipment at a correct position, thereby ensuring the accuracy of equipment displacement monitoring.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

According to the Faraday's principle of electromagnetic induction, when a block-shaped metal conductor is placed in a changing magnetic field or moves to cut magnetic lines of force in the magnetic field, eddy-shaped induced current is generated in the conductor, and the current is called eddy current, which is called eddy current effect. While sensors made from the eddy current effect are referred to as eddy current sensors.

The high-frequency oscillating current in the front-end of the current vortex sensor flows into the probe coil through the extension cable, and an alternating magnetic field is generated in the coil of the probe head. When the metal body to be detected is close to the magnetic field, an induced current is generated on the metal surface, and simultaneously the induced current field also generates an alternating magnetic field with the direction opposite to the direction of the magnetic field generated by the coil of the probe head, so that the amplitude and the phase of the high-frequency current of the coil of the probe head are changed (namely the effective impedance of the coil of the probe head is changed) due to the reaction of the alternating magnetic field, and the change is related to parameters such as the magnetic permeability, the electric conductivity, the geometric shape and the geometric dimension of the coil, the current frequency, the distance from the coil of the probe head to the surface of the metal conductor and the like. Assuming generally that the metallic conductor material is uniform and the performance is linear and isotropic, the physical properties of the coil and metallic conductor system can be described by the parameters of the conductivity Be, the permeability ξ, the size factor τ of the metallic conductor, the distance D between the coil of the probe head and the surface of the metallic conductor, the current intensity I and the frequency ω. The characteristic impedance of the coil can be represented by a function Z ═ F (τ, ξ, σ, D, I, ω).

Usually, several parameters of τ, ξ, δ, I and ω can be controlled to be constant within a certain range, so that the characteristic impedance Z of the coil becomes a single-value function of the distance D, and although the whole function is nonlinear, the function is characterized by an "S" type curve, a section which is approximate to linear can be selected. Meanwhile, through the processing of an electronic circuit in the front-end device, the change of the coil impedance Z (namely the change of the distance D between the head body coil and the metal conductor) can be converted into a voltage or current signal to be output, and the magnitude of the output signal is changed along with the distance between the probe and the surface of the measured body. The eddy current sensor is used for measuring parameters such as displacement, vibration and the like of a metal object according to the principle.

When the distance between the metal to be measured and the probe is changed, the Q value of a coil in the probe is also changed, the change of the Q value causes the change of the amplitude of the oscillation voltage, the oscillation voltage which is changed along with the distance is converted into the change of voltage (or current) through the detection, filtering, linear compensation and amplification normalization processing, and finally the distance (namely the gap between the front end of the probe and the surface of the metal to be measured) is converted into the voltage (or current), so that the measurement of the vibration displacement of the metal to be measured is realized. From the above, the measured object in the operating system of the eddy current sensor can be regarded as a half of the sensor system, i.e. the performance of one eddy current displacement sensor is related to the measured object.

Embodiment 1 is a specific configuration of an eddy current sensor probe provided by the present invention; embodiment 2 is a specific configuration of an eddy current sensor provided by the present invention; embodiment 3 is an operation principle of an eddy current sensor provided by the present invention.

Example 1

Fig. 1 is a perspective view of an eddy current sensor provided by the present invention, and as shown in fig. 1, an eddy current sensor probe provided by the present invention includes a probe body (including 1, 2, 3, and 4 in fig. 1), at least one protrusion, and at least one position monitoring coil (including 6 and 7 in fig. 1).

Specifically, the front end of the probe main body penetrates through the shell of the monitored object and extends into the monitored object; the probe main body is used for monitoring the distance between the front end of the probe main body and the inner core of the monitored object, and an equipment position monitoring signal is obtained.

The at least one protrusion is evenly distributed at the rear end of the probe body.

The at least one position monitoring coil is used for monitoring the distance between the position monitoring coil and the shell of the monitored object to obtain a corresponding relative position monitoring signal.

In addition, the number of the position monitoring coils is equal to that of the protrusions, and the position monitoring coils correspond to the protrusions one by one; a gap exists inside the protrusion body as a first gap; the first gap is used for storing the position monitoring coil and the peripheral circuit.

The probe main body monitors the distance between the probe main body and the inner core of the monitored object to obtain an equipment position monitoring signal, the distance between the probe main body and the outer shell of the monitored object is monitored by the position monitoring coil, and the working principles of obtaining the relative position monitoring signal are the eddy current effect.

Further, the eddy current sensor probe further comprises at least one supporting body 5, wherein the supporting bodies 5 are respectively embedded in the protruding bodies and located between the position monitoring coil and the probe body, and are used for supporting and protecting the position monitoring coil; the supporting bodies 5 correspond to the protrusions in a one-to-one manner, and the number of the supporting bodies is equal to that of the protrusions.

Further, the probe body includes a front end case 2, a rear end case 4, and a device monitoring coil 1.

Specifically, the front end housing 2 penetrates the outer shell of the monitored object and protrudes into the inside of the monitored object. The rear end shell 4 is connected with the front end shell 2 and is used for adjusting the length of the front end shell 2 extending into the monitored object; the protrusions are evenly distributed around the rear housing 4. The equipment monitoring coil 1 is located inside the front end shell 2 and used for monitoring the distance between the equipment monitoring coil 1 and the inner core of the monitored object to obtain an equipment position monitoring signal.

Fig. 2 is a top view of an eddy current sensor probe according to the present invention, as shown in fig. 1 and 2, the front housing 2 and the rear housing 4 are both cylinders; and the front end housing 2 and the rear end housing 4 have the same outer diameter.

In this embodiment, the number of the protrusions, the number of the supporting bodies, and the number of the position monitoring coils are two; the shapes of the protruding body and the supporting body are cuboids; the two position monitoring coils are referred to as a first position monitoring coil 6 and a second position monitoring coil 7, respectively. However, the present invention is not limited to this, and may be adjusted according to actual conditions such as the external shape of the object and the size of the object.

As a specific implementation manner of this embodiment, the surface of the rear end housing 4 is covered with threads; the eddy current sensor probe adjusts the length of the front end shell 2 extending into the monitored object through the threads, and fixes the front end shell 2 at a set position.

Preferably, the front end housing 2 is in concave-convex connection with the rear end housing 4; the tail part of the front end shell 2 protrudes outwards, the position where the head part of the rear end shell 4 is connected with the front end shell 2 is recessed inwards, and the front end shell 2 and the rear end shell are mutually embedded and fixed.

Preferably, a gap exists inside the front end housing 2 as a second gap 3; the second gap 3 is used for storing the equipment monitoring coil 1 and peripheral circuits.

Preferably, a gap exists inside the rear end housing 4 as a third gap 8; the third gap 8 communicates with the first gap and the second gap 2, respectively.

Example 2

As shown in fig. 1, the eddy current sensor provided by the invention comprises the eddy current sensor probe, a transmission shielding signal wire 9 and a front-end device.

Specifically, the transmission shield signal line 9 is connected to the device monitoring coil 1 located in the probe body and the position monitoring coil (including 6 and 7 in fig. 1) located in the protrusion, respectively.

The pre-processor is connected with the transmission shielding signal wire 9 and is used for respectively providing high-frequency oscillation current for generating an eddy current effect for the equipment monitoring coil 1 and the position monitoring coil. The front-end device is also used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

Further, the eddy current sensor further includes a cable plug 10; the transmission shielded signal line 9 is connected to the front connector through the cable plug 10.

As a specific implementation manner of this embodiment, the transmission shielding signal line 9 is composed of a plurality of coaxial cables; the number of the coaxial cables is equal to the total number of the equipment monitoring coils 1 and the position monitoring coils; the plurality of coaxial cables are connected to the device monitoring coil 1, the position monitoring coil, and the pre-stage unit, respectively.

Further, the pre-stage includes an oscillator and a controller.

Specifically, the oscillator is connected to the transmission shielding signal line 9, and is configured to provide high-frequency oscillation currents for generating an eddy current effect to the position monitoring coil of the device monitoring coil 1, respectively; the controller is connected with the transmission shielding signal wire and used for obtaining the vibration displacement of the monitored object according to the equipment position monitoring signal and judging whether the probe of the eddy current sensor displaces or not according to the relative position monitoring signal.

Preferably, the oscillator is a crystal oscillator; the controller is an STC single-chip microcomputer, an STM32 single-chip microcomputer or a data acquisition card, but is not limited to the STC single-chip microcomputer, the STM32 single-chip microcomputer or the data acquisition card, and the controller can be adjusted according to actual needs.

Further, the eddy current sensor further comprises an alarm; the alarm is connected with the controller and used for sending out an alarm according to the prompt signal; the prompt signal is generated by the controller when the probe of the eddy current sensor displaces.

Preferably, the alarm is a horn, an indicator light or the like.

Taking the number of the position monitoring coils of the probe of the eddy current sensor provided by the invention as an example, fig. 3 is a schematic view of the working principle of the eddy current sensor provided by the invention, as shown in fig. 3, the using steps and the specific working principle of the eddy current sensor are as follows:

1) when waiting to monitor equipment when the stall, at first polish at the position that waits to monitor equipment needs to be monitored to guarantee that this position is level and smooth, clean and tidy, then punch, insert 2 inside of front end casing with the eddy current sensor probe, with screw thread adjustment position and fixed on the rear end casing 4 of eddy current sensor probe.

2) After the probe of the eddy current sensor is completely fixed, when the equipment is in a static state, the position monitoring coil 6 measures the distance d1 between the probe and the surface of the equipment to be monitored to obtain and record a first initial voltage V1; the position monitoring coil 7 measures its distance d2 to the surface of the device to be monitored, and a second initial voltage V2 is obtained and recorded.

3) And when the equipment starts to operate, the equipment monitoring coil 1 starts to measure the vibration displacement of the equipment to be monitored. Meanwhile, the first position monitoring coil and the second position monitoring coil continuously measure the distances from the first position monitoring coil and the second position monitoring coil to the surface of the device to be monitored to obtain corresponding voltage quantities v1 and v2 respectively, and the collected voltage quantities are transmitted to the controller for processing through the peripheral circuit and the transmission shielding signal wire.

4) And the controller compares the voltage quantities V1 and V2 collected under the equipment running state with the initial voltages V1 and V2 respectively. If V1-V1 is 0 and V2-V2 is 0, it indicates that the distances d1 and d2 from the first position monitoring coil 6 and the second position monitoring coil 7 to the surface of the device respectively do not change at present, the probe of the eddy current sensor does not generate displacement, and the data acquired by the monitoring coil of the device is normal; if V1-V1 is not equal to 0 or V2-V2 is not equal to 0, the fact that the distance d1 or d2 between the first position monitoring coil 6 and the second position monitoring coil 7 and the surface of the equipment changes currently indicates that the probe of the eddy current sensor is displaced, namely loosened, the actual displacement of the equipment is not measured by the eddy current sensor at the moment, and the controller can generate a prompt signal to prompt a person to go to the field for processing.

Compared with the prior art, the sensor provided by the invention can ensure that the probe always monitors equipment at the correct position through self-monitoring, so that the accuracy of a monitoring value can be ensured. After the probe of the eddy current sensor is displaced, the measured data often has deviation, and if the system has no prompt, an error result is easily generated, so that technicians make wrong judgments, and production is influenced. When the eddy current sensor provided by the invention generates displacement or deviation, technicians can be prompted in time to fix or record the probe of the eddy current sensor again, so that the influence on production is avoided.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to assist in understanding the core concepts of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.