Optical fiber F-P cavity sensing probe
By designing a small fiber F-P cavity sensing probe, using quartz sheets and single-mode fibers to form a Fabripero interference cavity, the problem that existing equipment cannot penetrate deep into the electrical appliance to detect weak ultrasonic signals, achieving high sensitivity and accuracy Ultrasonic signal detection.
Patent Information
- Application Number
- CN202420769842.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-15
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-04-15
AI Technical Summary
The existing ultrasonic detection equipment is large in size and cannot be tested deeply into the electrical appliances. It is difficult to make stable judgments on weak ultrasonic signals, and the detection sensitivity is low.
An optical fiber F-P cavity sensing probe is designed, including a support layer with a three-dimensional size of less than 1 cm and a ceramic ferrule. It uses quartz sheets and single-mode optical fiber to form a Fabripelo interference cavity, and detects weak ultrasonic signals through interference signals.
It realizes ultrasonic signal detection with small size, wide dynamic range, anti-electromagnetic interference and high sensitivity. It is suitable for placement inside electrical equipment, improving detection accuracy and sensitivity, and is suitable for a variety of detection scenarios.
Smart Images
Figure CN222336390U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of optical fiber sensors, in particular to an optical fiber FP cavity sensing probe for detecting ultrasound. Background Art
[0002] Power cables are operated outdoors for a long time and are easily affected by the external environment, which leads to the degradation of insulation performance and partial discharge. When partial discharge occurs in electrical appliances, ultrasonic signals are released. By detecting these ultrasonic signals, it can be determined whether the electrical appliances have defects.
[0003] The ultrasonic signal of partial discharge generated by electrical appliances is very weak, and the space inside the electrical equipment is small. The existing ultrasonic detection equipment is large in size and cannot penetrate deeply into the interior of the appliance for detection. It is difficult to make stable judgments on weak ultrasonic signals, and the detection sensitivity is low. Utility Model Content
[0004] In order to solve the defects of existing ultrasonic detection equipment that is large in size, the detection equipment cannot penetrate into the interior of the electrical appliance for detection, and it is difficult to make a stable judgment on weak ultrasonic signals, the utility model proposes an optical fiber FP cavity sensing probe.
[0005] The technical solution adopted by the utility model is a fiber FP cavity sensing probe, comprising: a support layer, which has three-dimensional dimensions all less than 1 cm, comprising a quartz plate one, a quartz plate two and a quartz plate three which are stacked in sequence, a through hole one being provided in the middle of the quartz plate one, a through hole two being provided in the middle of the quartz plate two opposite to the through hole one, and an inner diameter of the through hole one being greater than an inner diameter of the through hole two; a ceramic ferrule, one end of which is inserted into the through hole one and abuts against the quartz plate two, and a single-mode optical fiber being axially inserted in the middle of the ceramic ferrule.
[0006] Preferably, the inner diameter of the through hole 1 is the same as the outer diameter of the ceramic insert.
[0007] Preferably, the single-mode optical fiber is a single-mode bare optical fiber.
[0008] Preferably, the ceramic ferrule, the first quartz plate, the second quartz plate and the third quartz plate are bonded and fixed in sequence.
[0009] Preferably, the thickness of the quartz plate three is 0.2 mm.
[0010] Preferably, the length and width of the quartz plate 1, the quartz plate 2 and the quartz plate 3 are all 5 mm.
[0011] Preferably, the inner diameter of the through hole 1 is 2.5 mm, the inner diameter of the through hole 2 is 2 mm, and the thickness of the quartz plate 2 is 1 mm.
[0012] Compared with the prior art, the utility model has the following beneficial effects:
[0013] The optical fiber FP cavity sensing probe of the utility model has the advantages of small size, wide dynamic range, anti-electromagnetic interference, high sensitivity, etc., and its size can be limited to less than 1 cm, which is suitable for being placed inside electrical equipment, and can detect weak ultrasonic signals more accurately, which is convenient for promotion and application; the sensing probe has a simple structure, and is composed of three layers of quartz sheets with the same material, which reduces the thermal expansion effect of the joints of different parts, reduces the influence of the thermal expansion of the external temperature on the sensing probe, improves the sensing accuracy of the sensing probe at different temperatures, and can be mass-produced, which is convenient for production and manufacturing, and saves costs; the material of the sensing probe is mainly quartz sheets, which are resistant to high temperatures and corrosion, and can detect ultrasonic signals in electrical appliances for a long time, and can be applied to various detection scenarios such as pressure detection and gas detection. In addition, the quartz film has a higher first-order natural frequency, so the frequency detection range of the device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention is described in detail below with reference to the embodiments and drawings, wherein:
[0015] Figure 1 It is the overall structural diagram of the optical fiber FP cavity sensing probe;
[0016] Figure 2 yes Figure 1 Side view of
[0017] Figure 3 It is a partial structural schematic diagram of the optical fiber FP cavity sensing probe.
[0018] 1. Quartz sheet one; 2. Quartz sheet two; 3. Quartz sheet three; 4. Ceramic ferrule; 5. Single-mode optical fiber. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solution and advantages of the utility model clearer, the embodiments of the utility model will be further described in detail below in conjunction with the accompanying drawings. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar components or components with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the utility model, and cannot be interpreted as limiting the utility model.
[0020] In one embodiment, Figure 1-3As shown, a fiber FP cavity sensing probe includes a support layer and a ceramic ferrule 4, each of which has three-dimensional dimensions less than 1 cm. The support layer includes a quartz plate 1, a quartz plate 2, and a quartz plate 3, which are stacked in sequence. A through hole 1 is provided in the middle of the quartz plate 1, and a through hole 2 is provided in the middle of the quartz plate 2. The through hole 2 is directly opposite to the through hole 1, and the inner diameter of the through hole 1 is greater than the inner diameter of the through hole 2. One end of the ceramic ferrule 4 is inserted into the through hole 1, and the end abuts against the quartz plate 2, and the other end of the ceramic ferrule 4 is arranged outside the support layer. A single-mode optical fiber 5 is axially inserted into the middle of the ceramic ferrule 4.
[0021] like Figure 2 As shown, through hole 2, quartz plate 3 3 and ceramic ferrule 4 constitute the optical fiber FP cavity. The thickness of quartz plate 2 2 with through hole 2 is the cavity length of the optical fiber FP cavity, which can be 1 mm. Quartz plate 3 3 is a sensing film, and its thickness is the thickness of the sensing film. The inner diameter of through hole 2 is the diameter of the sensing film. The single-mode optical fiber 5 is connected to the laser, and the light emitted by the laser reaches the inside of the interference cavity through the single-mode optical fiber 5 to form an interference signal, and the interference signal is visualized by an oscilloscope. The end faces of the sensing film and the single-mode optical fiber 5 constitute the cavity reflection surface of the optical fiber FP cavity. When the external ultrasonic signal acts on the quartz film, the tiny vibration of the air disturbed by the ultrasonic signal will cause the quartz film to produce a weak vibration, thereby changing the interference optical path inside the optical fiber FP cavity. By detecting the change of the interference optical path, the external ultrasonic signal can be sensed.
[0022] The optical fiber FP cavity sensor probe in this embodiment is based on the Fabry-Perot interferometer cavity design of optical fiber, and has the advantages of small size, wide dynamic range, anti-electromagnetic interference, high sensitivity, etc. The size can be limited to less than 1 cm, which is suitable for being placed inside electrical equipment, and more accurately detecting weak ultrasonic signals, which is convenient for promotion and application; the sensor probe has a simple structure, consisting of three layers of quartz sheets, with the same material, which reduces the thermal expansion effect of the joints of different parts, reduces the thermal expansion effect of the external temperature on the sensor probe, improves the sensing accuracy of the sensor probe at different temperatures, and can be mass-produced, which is convenient for production and manufacturing, and saves costs; the material of the sensor probe is mainly quartz sheets, which are resistant to high temperatures and corrosion, and can detect ultrasonic signals in electrical appliances for a long time, and can be applied to various detection scenarios such as pressure detection and gas detection. In addition, the quartz film has a higher first-order natural frequency, so the frequency detection range of the device can be improved.
[0023] The thickness of the quartz plate 1 can be set to 1 mm. In other embodiments, the thickness of the quartz plate 1 and the quartz plate 2 can also be specifically set according to the size of the electrical appliance to be detected.
[0024] In one embodiment, the inner diameter of the through hole 1 is the same as the outer diameter of the ceramic ferrule 4, so that the ceramic ferrule 4 can be stably inserted into the quartz plate 1 to ensure the stability of the overall structure of the sensor probe.
[0025] In one embodiment, the single-mode optical fiber 5 is a single-mode bare optical fiber. Bare optical fiber refers to an optical fiber without an external coating or outer protective layer. It has a smaller diameter, is softer and more flexible; there is no protective layer to absorb or scatter signals, and the loss is low; it can be directly bonded to other objects, and the sensing effect is more sensitive and the cost is lower.
[0026] In one embodiment, the thickness of the quartz sheet 3 3 is 0.2 mm. The quartz sheet 3 3 is a sensing membrane used to sense ultrasonic signals. The thinner thickness of the quartz sheet 3 3 can more sensitively sense the tiny vibrations generated by the ultrasonic signal, so as to detect very weak ultrasonic signals and achieve higher detection sensitivity. In other embodiments, the quartz sheet 3 3 can also select other thicknesses, such as 0.05 mm, 0.1 mm, etc., which can bring higher sensitivity; and can also select larger sizes such as 0.3 mm, 0.4 mm, etc. according to the requirements of sensitivity and stability.
[0027] In one embodiment, the length and width of the quartz plate 1 1, the quartz plate 2 2 and the quartz plate 3 3 are all 5 mm. The smaller size makes it easier to place the sensor probe inside the electrical device and detect weak ultrasonic signals more accurately. In other embodiments, the length and width of the quartz plate 1 1, the quartz plate 2 2 and the quartz plate 3 3 can also be changed according to different detection requirements to adapt to measurements in different frequency ranges.
[0028] In one embodiment, the inner diameter of through hole 1 is 2.5 mm, the inner diameter of through hole 2 is 2 mm, through hole 1 and through hole 2 are arranged opposite to each other, so that part of the surface of quartz plate 2 is exposed at one through hole, and the intersection of through hole 1 and through hole 2 forms a step shape, so that the ceramic ferrule 4 is fixed in through hole 1, and through hole 2 forms the optical fiber FP cavity. In other embodiments, the inner diameter of through hole 1 can be selected according to the diameter of the ceramic ferrule actually selected; the inner diameter of through hole 2 represents the diameter of the sensing diaphragm, which can be set according to different requirements of the measurement frequency range and sensitivity, and it is necessary to ensure that the inner diameter of through hole 1 is larger than the inner diameter of through hole 2.
[0029] In one embodiment, the ceramic ferrule 4, the quartz plate 1, the quartz plate 2 and the quartz plate 3 are bonded and fixed in sequence to ensure that the position and connection of each component are firm, and the structural integrity is stronger, thereby improving the mechanical strength and durability of the optical fiber FP cavity sensing probe.
[0030] In one embodiment, a method for making a fiber FP cavity sensor probe as in the above embodiment includes: using a hydrogen-oxygen catalytic bonding method to sequentially bond and fix quartz plate 1, quartz plate 2, and quartz plate 3. Specifically, hydrogen-oxygen catalytic bonding is a bonding technology based on hydroxide-catalyzed hydration and dehydration reactions to achieve material surface connection, which allows the hydration and dehydration processes to easily occur at room temperature so as to form a bond at room temperature. Using a hydrogen-oxygen catalytic bonding method to bond and fix quartz plate 1, quartz plate 2, and quartz plate 3, has the advantages of simple process, easy operation, high bonding strength, adaptability to extreme temperature environments, and short production cycle. In other embodiments, quartz plate 1, quartz plate 2, and quartz plate 3 can also be fixedly connected by other methods, such as heat-resistant polymer adhesive bonding, welding, etc.
[0031] In one embodiment, a method for manufacturing a fiber FP cavity sensor probe as in the above embodiment includes: using ultraviolet curing glue to bond and fix the ceramic ferrule 4 to the through hole 1 and the quartz plate 2 2 respectively. The ultraviolet curing glue is an adhesive with a photoinitiator, which can form a polymer network structure under ultraviolet light irradiation, thereby achieving curing, and has the advantages of high strength and fast curing. In other embodiments, the through hole 1 and the quartz plate 2 2 can also be fixedly connected by other methods, such as thermosetting glue bonding, snap-on fixed connection, etc.
[0032] Specifically, quartz plate 1, quartz plate 2, and quartz plate 3 are bonded into a complete quartz fixing device by a hydrogen-oxygen catalytic bonding method, and then the ceramic ferrule 4 is inserted into the through hole 1 to contact the quartz plate 2, and the ceramic ferrule 4 is bonded and fixed to the through hole 1 and the quartz plate 2 2 respectively by ultraviolet curing glue, thereby achieving the bonding of the entire quartz fixing device and the ceramic ferrule 4.
[0033] In one embodiment, an application of the optical fiber FP cavity sensing probe as in the above embodiment is used for ultrasonic detection inside electrical equipment. In other embodiments, the optical fiber FP cavity sensing probe can also be used in various detection scenarios such as pressure detection and gas detection.
[0034] In the description of this specification, if the terms "embodiment 1", "this embodiment", "in an embodiment" and the like appear, it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the invention or utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example; moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in an appropriate manner.
[0035] In the description of this specification, the terms "connect", "install", "fix", "set", "have", etc. are all understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0036] In the description of this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.
[0037] The above description of the embodiments is to facilitate ordinary technicians in the technical field to understand and apply the technology of this case. People familiar with the technology in this field can obviously make various modifications to these examples easily and apply the general principles described here to other embodiments without creative work. Therefore, this case is not limited to the above embodiments. Modifications to the following situations should all be within the scope of protection of this case: ① A new technical solution based on the technical solution of the utility model and combined with existing common knowledge, the technical effect produced by the new technical solution does not exceed the technical effect of the utility model; ② The equivalent replacement of some features of the technical solution of the utility model by using known technology, the technical effect produced is the same as the technical effect of the utility model; ③ The technical solution of the utility model can be expanded based on the technical solution of the utility model, and the substantive content of the expanded technical solution does not exceed the technical solution of the utility model; ④ The equivalent transformation made by using the contents of the specification and drawings of the utility model is directly or indirectly applied to other related technical fields.
Claims
1. An optical fiber FP cavity sensing probe, characterized in that: Including those with three dimensions less than 1 cm: A support layer, comprising a quartz plate 1, a quartz plate 2 and a quartz plate 3 stacked in sequence, wherein a through hole 1 is provided in the middle of the quartz plate 1, a through hole 2 is provided in the middle of the quartz plate 2 opposite to the through hole 1, and an inner diameter of the through hole 1 is greater than an inner diameter of the through hole 2; A ceramic ferrule has one end inserted into the first through hole and abutting against the second quartz plate, and a single-mode optical fiber is axially inserted into the middle of the ceramic ferrule.
2. The optical fiber FP cavity sensing probe according to claim 1, characterized in that: The inner diameter of the through hole 1 is the same as the outer diameter of the ceramic insert.
3. The optical fiber FP cavity sensing probe according to claim 1, characterized in that: The single-mode optical fiber is a single-mode bare optical fiber.
4. The optical fiber FP cavity sensing probe according to claim 1, characterized in that: The ceramic ferrule, the first quartz sheet, the second quartz sheet and the third quartz sheet are bonded and fixed in sequence.
5. The optical fiber FP cavity sensing probe according to claim 4, characterized in that: The thickness of the quartz plate three is 0.2 mm.
6. The optical fiber FP cavity sensing probe according to claim 1, characterized in that: The length and width of the quartz plate 1, the quartz plate 2 and the quartz plate 3 are all 5 mm.
7. The optical fiber FP cavity sensing probe according to claim 1, characterized in that: The inner diameter of the through hole 1 is 2.5 mm, the inner diameter of the through hole 2 is 2 mm, and the thickness of the quartz plate 2 is 1 mm.