Ultraviolet lamp and gas sensor

Abstract

The application provides a kind of ultraviolet lamp, including glass lamp tube, ultraviolet light output window and metal support made of non-volatile active metal, ultraviolet light output window is sealedly connected with one end of glass lamp tube, metal support is located in glass lamp tube, metal support includes the first bifurcation with elasticity and the second bifurcation, the first bifurcation and the second bifurcation one end are connected, the other end extends in the direction away from ultraviolet light output window, and respectively with the different surface of glass lamp tube contact.The application adds the metal support with bifurcation structure in the inside of glass lamp tube, can conduct a part of barrier charge generated due to static electricity, so that working gas is broken down in advance under relatively lower external excitation voltage, improves the collision probability between working gas molecules, working gas is more easily excited, reduces excitation voltage, can also absorb most of impurity gas except inert working gas, makes ultraviolet lamp long-term stable working state, improves device performance and service life.

Description

Technical Field

[0001] This invention relates to the field of gas detection technology, and in particular to an ultraviolet lamp and a gas sensor. Background Technology

[0002] The gas sensor, including the PID (Photo Ionization Detector) sensor, is internally equipped with a high-voltage module that drives the ultraviolet lamp, the ultraviolet lamp itself, and a detection module that detects the gas concentration. The high-voltage alternating current generated by the high-voltage module is applied to a pair of metal electrodes on the outside of the ultraviolet lamp's glass tube. The electric field formed between the metal electrodes applies energy to the working gas inside the lamp tube, causing it to break down and emit ultraviolet light. The ultraviolet light passes through the output window on the ultraviolet lamp, ionizing the gas being detected. When the ionized gas passes through the detection module, it can be detected as an electric current, and the concentration value of the gas being measured can be calculated.

[0003] Vacuum ultraviolet lamps are mainly used in photoionization detection sensors such as PID and GC (gas chromatography). PID sensors, as professional sensors for detecting VOCs (Volatile Organic Compounds) in environmental protection and industrial safety fields, have advantages such as small size, fast response speed, high accuracy, and continuous measurement capability. They can detect VOCs and other toxic and harmful gases from extremely low concentrations of 1 ppb to high concentrations of tens of thousands of ppm. Currently, PID sensors are widely used in the detection of various organic chemicals, playing a particularly important role in disaster area accident leak detection, accident area confirmation, and leak identification. The performance and lifespan of the vacuum ultraviolet lamp have always been key factors determining the quality of PID sensors. Improving the performance and lifespan of ultraviolet lamps is also a continuous pursuit for PID sensor developers. In existing technologies, methods to improve the lifespan of gas sensors mainly involve changing the output light intensity by altering the ultraviolet lamp's driving voltage to extend the lifespan of components around the ultraviolet lamp. However, this may lead to the ultraviolet lamp malfunctioning and has limited adjustment range. To address this, the inventors of this application, after long-term research, have proposed an improved solution. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an ultraviolet lamp and a gas sensor to solve the problems in the prior art where changing the output light intensity by changing the driving voltage of the ultraviolet lamp to extend the service life of the components around the ultraviolet lamp, thereby improving the service life of the gas sensor, may lead to the ultraviolet lamp failing to work properly and the adjustment range being limited.

[0005] To achieve the above and other related objectives, the present invention provides an ultraviolet lamp, which includes a glass tube, an ultraviolet light output window, and a metal bracket made of a non-evaporative reactive metal. The ultraviolet light output window is sealed to one end of the glass tube, and the metal bracket is located inside the glass tube. The metal bracket includes a first branch and a second branch with elasticity. One end of the first branch and the second branch are connected, and the other end extends in a direction away from the ultraviolet light output window, and each branch contacts a different surface of the glass tube.

[0006] Optionally, the glass lamp tube includes a first cavity and a second cavity connected to each other, the inner diameter of the first cavity is larger than the inner diameter of the second cavity, the ultraviolet light output window is connected to the end of the first cavity away from the second cavity, the metal bracket is located in the first cavity, and the first branch and the second branch extend to be adjacent to the connection surface of the first cavity and the second cavity.

[0007] Optionally, the connection surface between the first cavity and the second cavity is a conical surface, and the glass lamp tube and the ultraviolet light output window are airtightly connected by a sealing material.

[0008] Optionally, the metal support may be made of one or both of vanadium and vanadium alloys.

[0009] Optionally, the metal bracket further includes a resilient third and fourth branch, the first, second, third and fourth branches being connected together, and the third and fourth branches extending in a direction away from the first and second branches to contact the ultraviolet light output window.

[0010] Optionally, the ultraviolet lamp further includes an ultraviolet light attenuator made of a material that cannot transmit ultraviolet light, located inside the glass lamp tube and adjacent to the ultraviolet light output window, the metal bracket abutting against the end of the ultraviolet light attenuator away from the ultraviolet light output window, and the ultraviolet light attenuator having a plurality of transmission holes, the total transmission area of ​​the plurality of transmission holes being smaller than the light-transmitting area of ​​the ultraviolet light output window.

[0011] In one alternative embodiment, the ultraviolet lamp further includes an ultraviolet filter located inside the glass lamp tube and adjacent to the ultraviolet output window. The metal bracket abuts against the end of the ultraviolet filter opposite to the ultraviolet output window. The ultraviolet light transmittance of the ultraviolet filter is less than that of the ultraviolet light transmittance of the ultraviolet output window.

[0012] In another alternative embodiment, the ultraviolet lamp further includes an ultraviolet filter located inside the glass lamp tube. The ultraviolet filter and the ultraviolet attenuator are stacked and adjacent to the ultraviolet output window. The ultraviolet light transmittance of the ultraviolet filter is less than that of the ultraviolet light transmittance of the ultraviolet output window.

[0013] Optionally, the material of the ultraviolet light output window includes magnesium fluoride crystal, and the material of the ultraviolet light filter includes one or both of calcium fluoride crystal and alumina crystal.

[0014] The present invention also provides a gas sensor, the gas sensor comprising an ultraviolet lamp as described in any of the above embodiments.

[0015] As described above, the ultraviolet lamp and gas sensor of the present invention have the following beneficial effects: The present invention creatively adds a metal bracket with a forked structure inside the glass lamp tube. During the manufacturing process of the ultraviolet lamp, this metal bracket can be inserted into the glass lamp tube through the opening at the tail end. After insertion, under the action of elasticity, the forked part will automatically open and fix itself inside the glass lamp tube, preventing it from sliding out from the tail end of the lamp tube and damaging the equipment in subsequent processes. On the one hand, the metal bracket can conduct some of the barrier charge generated by electrostatic action, allowing the working gas to be broken down earlier under a relatively low external excitation voltage, thus reducing the lighting voltage of the ultraviolet lamp, meaning the ultraviolet lamp is easier to light and consumes less power; on the other hand, the metal bracket is selected... Using a metallic material with a relatively high secondary electron emission coefficient allows for the release of a large number of electrons from the material surface under the influence of an external electric field and trace electrons. This significantly increases the collision probability between working gas molecules, making the working gas easier to excite and further reducing the excitation voltage. Furthermore, the non-evaporative, reactive metal used in the metal support exhibits strong resistance to ion bombardment. When the UV lamp is operating normally, the sputtering effect of the plasma inside the lamp tube is relatively weak, effectively reducing the evaporation rate of atoms on the metal surface. After long-term plasma bombardment, the metal support surface retains strong metallic activity, absorbing most impurity gases except for the inert working gas, ensuring the UV lamp remains in a stable operating state for extended periods. Therefore, the UV lamp provided by this invention significantly improves its performance and lifespan. Applying it to photoionization gas sensors such as PID sensors helps improve the performance and lifespan of gas sensors. Attached Figure Description

[0016] Figure 1 The diagram shown is a structural schematic of the glass tube of the ultraviolet lamp provided in Embodiment 1 of the present invention.

[0017] Figure 2 The diagram shown is a structural schematic of the metal bracket for the ultraviolet lamp provided in Embodiment 1 of the present invention.

[0018] Figure 3 and 4 The diagram shown is a schematic diagram of the assembly process of the ultraviolet lamp provided in Embodiment 1 of the present invention.

[0019] Figure 5The diagram shown is a structural schematic of the metal bracket for the ultraviolet lamp provided in Embodiment 2 of the present invention.

[0020] Figure 6 The diagram shown is a schematic diagram of the structure of the ultraviolet light attenuator of the ultraviolet lamp provided in Embodiment 3 of the present invention.

[0021] Figures 7 to 9 The diagram shown is a schematic diagram of the assembly process of the ultraviolet lamp provided in Embodiment 3 of the present invention. Detailed Implementation

[0022] The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. For ease of explanation, when detailing the embodiments of the present invention, the cross-sectional views showing the device structure are partially enlarged, not according to the general scale, and the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. Furthermore, in actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0023] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0024] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0025] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show components related to the present invention and are not drawn according to the actual number, shape, and size of the components in the actual implementation. In the actual implementation, the form, quantity, and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex. To keep the illustrations as concise as possible, not all structures are shown in the figures.

[0026] Please see Figures 1 to 9 .

[0027] Example 1

[0028] like Figures 1 to 4As shown, this invention provides an ultraviolet lamp, which includes a glass tube 1, an ultraviolet light output window 2, and a metal bracket 3 made of a non-evaporative reactive metal. The ultraviolet light output window 2 is sealed to one end of the glass tube 1 (or it can be described as the ultraviolet light output window 2 sealing the opening of the glass tube 1) to form a vacuum-sealed space. This sealed space is usually filled with an inert gas 5 as the working gas. By selecting different working gases, ultraviolet radiation of different energy values ​​can be excited, thereby allowing for the ionization and detection of different types of gases. The metal bracket 3 is located inside the glass tube 1. The metal bracket 3 includes a first branch 32 and a second branch 33 with elasticity. One end of the first branch 32 and the second branch 33 are connected to form a joint 31, which can contact or abut against the ultraviolet light output window 2. The other ends of the two branches extend in a direction away from the ultraviolet light output window 2 and each contacts a different surface of the glass tube 1. Preferably, the first branch 32 and the second branch 33 are distributed about the axial center line of the glass tube 1. Because the first branch 32 and the second branch 33 are elastic, they can close together under the action of external force and return to their original branch shape after the external force is released. Existing UV lamps lack a metal support. The excitation voltage of these lamps is relatively high because when an electrodeless UV lamp is excited by a high-voltage electric field outside the tube, a large amount of barrier charge is induced on the inner wall of the tube due to electrostatic effects. This barrier charge can form a reverse high-voltage electric field inside, breaking down the working gas and causing the bulb to emit light. However, the inventors of this application have creatively added a forked metal support inside the glass tube. During the UV lamp manufacturing process, this metal support can be inserted into the glass tube through an opening at the rear. After insertion, the forked portion will automatically open under the action of elasticity, securing itself inside the glass tube. This prevents it from slipping out of the rear of the tube and damaging the equipment during subsequent processes. The metal support also conducts some of the barrier charge generated by electrostatic effects, allowing the working gas to emit light at a relatively lower external excitation voltage. The breakdown of the front end reduces the starting voltage of the UV lamp, making it easier to light and thus consuming less power. Furthermore, the metal bracket is made of a metal material with a relatively high secondary electron emission coefficient. Under the influence of an external electric field and trace electrons, a large number of electrons can overflow from the material surface, greatly increasing the collision probability between working gas molecules and making the working gas more easily excited, further reducing the excitation voltage. In addition, the non-evaporative active metal used in the metal bracket has strong resistance to ion bombardment. When the UV lamp is in normal operation, the sputtering effect of the plasma inside the lamp tube is relatively weak, effectively reducing the evaporation rate of atoms on the metal surface. After long-term plasma bombardment, the surface of the metal bracket has strong metallic activity, which can absorb most impurity gases except for the inert working gas, allowing the UV lamp to maintain a stable working state for a long time.Therefore, the ultraviolet lamp provided by this invention can significantly improve its performance and lifespan. Applying it to photoionization gas sensors such as PID sensors can help improve the performance and lifespan of gas sensors.

[0029] The glass tube 1 is typically made of lead-free glass, such as a quartz glass shell, and its shape can be customized as needed. In a preferred example, the glass tube 1 includes a first cavity 11 and a second cavity 12 connected to each other. The non-connecting surfaces of the first cavity 11 and the second cavity 12 are the end faces of the glass tube 1. One end face 13 is sealed to the end face 21 of the ultraviolet light output window 2, and the other end face 14 is close to the tail tip 16 of the ultraviolet lamp. When assembling the ultraviolet lamp, the elasticity of the metal bracket 3 can be utilized. Using a tool, the metal bracket 3 can be pushed from the side of the end face 14 through the second cavity 12 into the first cavity 11, which is already sealed with the ultraviolet light output window 2. After entering the first cavity 11, the first branch 32 and the second branch 33 automatically spring open and cannot slide out of the second cavity 12, thus avoiding the huge risk of the metal bracket 3 falling into the exhaust platform and causing equipment damage. Preferably, the first cavity 11 and the second cavity 12 are integrally formed, for example, by molding. The inner diameter of the first cavity 11 is larger than the inner diameter of the second cavity 12. The ultraviolet light output window 2 is connected to the end of the first cavity 11 opposite to the second cavity 12. The metal bracket 3 is located inside the first cavity 11, and the first branch 32 and the second branch 33 extend to be adjacent to the connecting surface of the first cavity 11 and the second cavity 12. In a further example, the first cavity 11 and the second cavity 12 are cylindrical tubes, and the connecting surface 15 of the first cavity 11 and the second cavity 12 is a conical surface. This helps to smoothly transition between the two cavities and improves the strength of the glass lamp tube. The material of the ultraviolet light output window 2 can be determined according to the output requirements. In a preferred example, the material of the ultraviolet light output window 2 is magnesium fluoride crystal, which can be used to output ultraviolet light with an ionization energy of 10.6 eV.

[0030] In one example, the glass lamp tube 1 and the ultraviolet light output window 2 are sealed together using a sealing material, such as transparent UV adhesive. In other examples, an annular groove matching the opening of the glass lamp tube 1 can be formed on the ultraviolet light output window 2, with the glass lamp tube embedded within this groove to achieve a sealed connection. Alternatively, both methods can be used simultaneously: an annular groove is formed, and the edge of the glass lamp tube's opening is fixed within the groove using a sealing material such as UV adhesive to achieve a reliable seal. In a preferred example, the size of the ultraviolet light output window 2 is slightly larger than the surface sealing with the glass lamp tube 1, thus appearing as follows: Figure 1As shown, the ultraviolet light output window 2 extends outward from the sealing surface of the glass lamp tube 1 to form an outer edge surface (not shown). This not only helps to ensure a full seal between the two, but also the extended outer edge surface can protect the glass lamp tube from external impacts to a certain extent.

[0031] The material of the metal bracket 3 can be determined as needed. Any metal material that meets the aforementioned requirements for resistance to ion bombardment, has a strong ability to absorb impurity gases, and has a high secondary electron emission coefficient is suitable for this invention. In a preferred example, the metal bracket 3 can be made of one or both of vanadium and vanadium alloys, but it is not limited to these; other precious metal materials can also be used, and there are no strict limitations on this. The number of branches of the metal bracket 3 is not limited to two; it can also be three or more. However, setting two branches not only facilitates processing and assembly but also avoids overcrowding inside the glass lamp tube.

[0032] The exemplary assembly process of the ultraviolet lamp provided in this embodiment is as follows:

[0033] 1. Secure the glass lamp tube 1 and the ultraviolet light output window 2 together using sealing material 4;

[0034] 2. Using a tool, push the metal bracket 3 into the glass tube 1 through the opening at the rear end of the glass tube 1, as shown in the reference. Figure 3 As shown;

[0035] 3. Fill the glass lamp tube 1 with working gas 5 and seal the opening at the end face 14 to form a closed tail tip 16, thus completing the assembly. The structure after assembly is shown in the reference diagram. Figure 4 As shown.

[0036] Other structures of the ultraviolet lamp provided in this embodiment, such as electrodes, are basically the same as those in the prior art. Since this part is not the focus of this invention, it will not be elaborated on in detail.

[0037] Example 2

[0038] This embodiment provides an ultraviolet lamp with a different structure. The main difference between the ultraviolet lamp provided in this embodiment and the ultraviolet lamp provided in Embodiment 1 is that the ultraviolet lamp in Embodiment 1 has a metal bracket that is forked on only one side, while the other side is connected to form a joint; while the ultraviolet lamp provided in this embodiment has a metal bracket 7 structure that is referenced from the previous embodiment. Figure 5As shown, the metal bracket 7 not only has a first branch 72 and a second branch 73 connected to each other, but also includes a third branch 74 and a fourth branch 75 with elasticity. The first branch 72, the second branch 73, the third branch 74, and the fourth branch 75 are connected to form a joint 71. The third branch 74 and the fourth branch 75 extend in a direction away from the first branch 72 and the second branch 73 to contact the ultraviolet light output window 2. That is, the metal bracket is an elastic structure with forks at both ends and a joint in the middle, similar to an X-shape. The ultraviolet lamp provided in this embodiment is the same as the metal bracket in Embodiment 1 except that the structure of the metal bracket is different. The installation method of the metal bracket is also similar to that in Embodiment 1. After the forks at both ends of the metal bracket 7 are compressed using a tool, it is pushed into the first cavity 11 through the second cavity 12. The forks at both ends spring back open and cannot slide out of the second cavity 12.

[0039] The ultraviolet lamp provided in this embodiment also has all the advantages of the ultraviolet lamp in Embodiment 1 by adding a metal bracket inside the glass lamp tube.

[0040] For more information about the ultraviolet lamp, please refer to the foregoing content; for the sake of brevity, it will not be repeated here.

[0041] Example 3

[0042] This embodiment provides an ultraviolet lamp with another structure. In addition to having all the structures of the ultraviolet lamps in Embodiments 1 or 2, the ultraviolet lamp provided in this embodiment also includes an ultraviolet light attenuator 6 made of a material that cannot transmit ultraviolet light (the specific material is not limited, as long as it is resistant to ultraviolet sputtering and does not transmit ultraviolet light, such as quartz), located inside the glass lamp tube 1 and adjacent to the ultraviolet light output window 2. The metal bracket abuts against the end of the ultraviolet light attenuator 6 away from the ultraviolet light output window 2. The ultraviolet light attenuator 6 is provided with a plurality of transmission holes 62, the total transmission area of ​​which is smaller than the light-transmitting area of ​​the ultraviolet light output window 2. The ultraviolet light attenuator 6 is made of a material with zero ultraviolet light transmittance. By perforating, a small amount of ultraviolet light is allowed to pass through the small holes on the attenuator to the outside of the window, thereby achieving the purpose of controlling the output light intensity of the ultraviolet lamp. The structure of the ultraviolet light attenuator 6 can be referred to... Figure 6As shown, its shape matches the shape of the glass lamp tube 1 and the ultraviolet light output window 2. For example, the ultraviolet light output window 2 is usually circular, so the ultraviolet light attenuator 6 is correspondingly a circular structure. Several circular transmission holes 62 that can transmit ultraviolet light are processed on the circular surface. The outer diameter of the cylindrical surface 61 is usually slightly smaller than the inner diameter of the first cavity 11, so that it can move in the first cavity 11 for assembly. After assembly, under the elastic support of the metal bracket (for example, the metal bracket in Embodiment 2), the ultraviolet light attenuator 6 is always in contact with the ultraviolet light output window 2, which plays the role of limiting the intensity of the output ultraviolet light. The ultraviolet lamp provided in this embodiment, with the metal bracket set (therefore, the ultraviolet lamp provided in this embodiment has all the advantages of the ultraviolet lamps in Embodiments 1 and 2), further adds an ultraviolet light attenuator with transmission holes. Without adjusting the voltage, the required aperture and / or number of transmission holes can be set according to the required output ultraviolet light intensity, which solves the problem of excessive ultraviolet light intensity in some applications and helps to further extend the service life of the ultraviolet lamp.

[0043] The exemplary assembly process of the ultraviolet lamp provided in this embodiment is as follows (based on the ultraviolet lamp provided in Embodiment 2):

[0044] 1. Place the ultraviolet light attenuator 6 into the first cavity 11 of the glass lamp tube 1;

[0045] 2. Seal the glass lamp tube 1 to the ultraviolet light output window 2, as per reference. Figure 7 As shown;

[0046] 3. Invert the sealed glass lamp assembly so that the opening faces upward. Under the action of gravity, the ultraviolet light attenuator 6 and the ultraviolet light output window 2 are attached.

[0047] 4. Use a tool to push the metal bracket 7 into the first cavity 11, causing it to fork and open. This ensures that the ultraviolet light attenuator 6 remains in contact with the ultraviolet light output window 2, thus limiting the intensity of the output ultraviolet light. (Refer to...) Figure 8 As shown;

[0048] 5. Fill the glass lamp tube with working gas 5 and seal the filling port to obtain a sealed tail tip 16. (Refer to...) Figure 9 As shown.

[0049] For more information about the ultraviolet lamp, please refer to the foregoing content; for the sake of brevity, it will not be repeated here.

[0050] Example 4

[0051] This embodiment provides an ultraviolet lamp with another structure. In addition to having all the structures of the ultraviolet lamps in Embodiments 1 or 2, the ultraviolet lamp provided in this embodiment also includes an ultraviolet filter (not shown), located inside the glass lamp tube 1 and adjacent to the ultraviolet output window 2. The metal bracket abuts against the end of the ultraviolet filter opposite to the ultraviolet output window; that is, one side of the ultraviolet filter is in close contact with the ultraviolet output window, while the other side is supported by the metal bracket, maintaining a relatively fixed state. The ultraviolet light transmittance of the ultraviolet filter is less than that of the ultraviolet light transmittance of the ultraviolet output window. The ultraviolet filter can have different transmittances of ultraviolet light based on its material properties, filtering out a portion of the ultraviolet spectrum, thereby changing the output spectrum of the ultraviolet lamp. The material of the ultraviolet filter can be selected from different crystals as needed, for example, calcium fluoride crystal with an output ionization energy of 9.8 eV, or alumina crystal with an output ionization energy of 9.6 eV, or a combination of multiple materials including the aforementioned materials; there are no strict limitations. In addition to having all the advantages of the embodiments in Embodiments 1 and 2, the ultraviolet lamp provided in this embodiment can also be configured with filters that have different transmittance to ultraviolet light to obtain ultraviolet lamps with different output ionization energies, thereby enabling the development of photoionization sensors with specific detection ranges.

[0052] For more information about the ultraviolet lamp, please refer to the foregoing content; for the sake of brevity, it will not be repeated here.

[0053] Example 5

[0054] This embodiment provides an ultraviolet lamp with another structure. In addition to having all the structures of the ultraviolet lamps described in Embodiments 1 or 2, this ultraviolet lamp also includes the ultraviolet light attenuator shown in Embodiment 3 and the ultraviolet light filter shown in Embodiment 4. The ultraviolet light filter is located inside the glass lamp tube. The ultraviolet light filter and the ultraviolet light attenuator are stacked and adjacent to the ultraviolet light output window. The order of the ultraviolet light attenuator and the ultraviolet light filter is not strictly limited; for example, the ultraviolet light filter can be adjacent to the ultraviolet light output window while the ultraviolet light attenuator is located at the end of the ultraviolet light filter furthest from the ultraviolet light output window. The ultraviolet light transmittance of the ultraviolet light filter is less than that of the ultraviolet light output window. Supported by a metal bracket, the ultraviolet light filter and the ultraviolet light attenuator can be relatively stably fixed inside the glass lamp tube. By simultaneously adding the ultraviolet light filter and the ultraviolet light attenuator, the ultraviolet light output intensity can be adjusted more flexibly. For more information about the ultraviolet lamp, please refer to the foregoing content; for the sake of brevity, it will not be repeated here.

[0055] This invention also provides a gas sensor, which is a photoionization sensor, including but not limited to any one of a PID sensor and a GC sensor. The gas sensor includes an ultraviolet lamp as described in any of the above embodiments; therefore, the foregoing description of the ultraviolet lamp can be quoted in its entirety here, and will not be repeated for the sake of brevity. Except for using the ultraviolet lamp provided by this invention, the other structures of the gas sensor provided by this invention are not significantly different from those of the prior art. Since this part is not the focus of this invention, it will not be elaborated upon. By using the ultraviolet lamp provided by this invention, the performance and lifespan of the gas sensor provided by this invention can be significantly improved.

[0056] In summary, the present invention provides an ultraviolet lamp, comprising a glass tube, an ultraviolet light output window, and a metal bracket made of a non-evaporative reactive metal. The ultraviolet light output window is sealed to one end of the glass tube, and the metal bracket is located inside the glass tube. The metal bracket includes a first branch and a second branch with elasticity. One end of the first branch and the second branch are connected, and the other end extends in a direction away from the ultraviolet light output window, and each branch contacts a different surface of the glass tube. This invention creatively adds a forked metal bracket inside the glass lamp tube. During the UV lamp manufacturing process, this metal bracket is inserted into the glass lamp tube through an opening at the rear. After insertion, the forked portion automatically opens and secures itself inside the glass lamp tube under elastic force, preventing it from slipping out during subsequent processes and damaging the equipment. The metal bracket also conducts some of the barrier charge generated by electrostatics, allowing the working gas to break down earlier at a relatively low external excitation voltage, thus reducing the UV lamp's starting voltage—making it easier to light and consuming less power. Furthermore, the metal bracket is made of materials with relatively high secondary electron emission... The metallic material with a high coefficient of conductivity can, under the influence of an external electric field and trace electrons, cause a large number of electrons to overflow from its surface, greatly increasing the collision probability between working gas molecules and making the working gas easier to excite, further reducing the excitation voltage. Furthermore, the non-evaporable reactive metal used in the metal support has strong resistance to ion bombardment. When the UV lamp is in normal operation, the sputtering effect of the plasma inside the lamp tube is relatively weak, effectively reducing the evaporation rate of atoms on the metal surface. After long-term plasma bombardment, the surface of the metal support exhibits strong metallic activity, capable of absorbing most impurity gases other than the inert working gas, allowing the UV lamp to maintain a stable working state for a long time. Therefore, the UV lamp provided by this invention significantly improves its performance and lifespan. Its application in photoionization gas sensors such as PID sensors helps improve the performance and lifespan of gas sensors. Thus, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An ultraviolet lamp characterized in that, The ultraviolet lamp comprises a glass lamp tube, an ultraviolet light output window and a metal support made of a non-vaporized active metal, the ultraviolet light output window is sealingly connected with one end of the glass lamp tube, the metal support is located in the glass lamp tube, the metal support comprises a first branch and a second branch with elasticity, one end of the first branch and the second branch is connected to form a joint, the joint is in abutment with the ultraviolet light output window, the other end of the first branch and the second branch extends in a direction away from the ultraviolet light output window and is in contact with different surfaces of the glass lamp tube respectively, the glass lamp tube comprises a first cavity and a second cavity connected with each other, the inner diameter of the first cavity is larger than the inner diameter of the second cavity, the ultraviolet light output window is connected with one end of the first cavity away from the second cavity, the metal support is located in the first cavity and the first branch and the second branch extend to the adjacent connecting surface of the first cavity and the second cavity.

2. The ultraviolet lamp of claim 1, wherein The connecting surface of the first cavity and the second cavity is a conical surface, and the glass lamp tube and the ultraviolet light output window are in airtight connection through a sealing material.

3. The ultraviolet lamp of claim 1, wherein The metal support is made of one or both of vanadium and vanadium alloy.

4. The ultraviolet lamp of claim 1, wherein The metal support further comprises a third branch and a fourth branch with elasticity, the first branch, the second branch, the third branch and the fourth branch are connected, and the third branch and the fourth branch extend in a direction away from the first branch and the second branch to be in contact with the ultraviolet light output window.

5. The ultraviolet lamp according to any one of claims 1 to 4, characterized in that The ultraviolet lamp further comprises an ultraviolet light attenuation sheet made of a material that cannot transmit ultraviolet light, located in the glass lamp tube and adjacent to the ultraviolet light output window, the metal support is in abutment with one end of the ultraviolet light attenuation sheet away from the ultraviolet light output window, and the ultraviolet light attenuation sheet is provided with a plurality of transmission holes, and the total transmission area of the plurality of transmission holes is smaller than the light transmission area of the ultraviolet light output window.

6. The ultraviolet lamp of claim 1, wherein, The ultraviolet lamp further comprises an ultraviolet light filter located in the glass lamp tube and adjacent to the ultraviolet light output window, the metal support is in abutment with one end of the ultraviolet light filter away from the ultraviolet light output window, and the ultraviolet light transmission capability of the ultraviolet light filter is smaller than the ultraviolet light transmission capability of the ultraviolet light output window.

7. The ultraviolet lamp of claim 5, wherein, The ultraviolet lamp further comprises an ultraviolet light filter located in the glass lamp tube, the ultraviolet light filter and the ultraviolet light attenuation sheet are stacked and located adjacent to the ultraviolet light output window, and the ultraviolet light transmission capability of the ultraviolet light filter is smaller than the ultraviolet light transmission capability of the ultraviolet light output window.

8. The ultraviolet lamp of claim 7, wherein, The material of the ultraviolet light output window comprises magnesium fluoride crystal, and the material of the ultraviolet light filter comprises one or both of calcium fluoride crystal and aluminum oxide crystal.

9. A gas sensor, characterized by The gas sensor comprises the ultraviolet lamp according to any one of claims 1-8.

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