Cavity filter
By setting up a discharge isolation cylinder with high breakdown field strength in the cavity filter, the problem of insufficient power capacity of the traditional cavity filter under low air pressure is solved, and the effect of higher power capacity and lowering the resonant frequency is achieved.
Patent Information
- Application Number
- CN202421140329.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-23
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-05-23
AI Technical Summary
Traditional cavity filters are insufficient in low air pressure conditions at high altitude or high altitude environment, and are prone to discharge or micro discharge, resulting in sharp deterioration or failure of equipment performance.
A cavity filter is designed, by setting a discharge isolation cylinder between the tuning screw and the resonant rod, and using its high breakdown field strength properties, the discharge or microdischarge phenomenon is avoided, thereby increasing the power capacity.
It effectively avoids the discharge or microdischarge of the cavity filter under low air pressure, improves the power capacity, and brings an additional effect of reducing the resonant frequency, and is suitable for high altitude or high altitude environments.
Smart Images
Figure CN222601335U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of wireless communication equipment, and in particular, to a cavity filter. Background Art
[0002] A filter is a device that processes electromagnetic wave signals. Its main function is to allow useful signals to pass through as unattenuated as possible and to reflect and attenuate useless signals as much as possible. Compared with other types of filters, cavity filters have the advantages of large power capacity, small insertion loss, and high selectivity. At present, cavity filters are widely used in communication equipment to select the frequency of transmitted or received signals. However, for communication equipment used in high-altitude or high-altitude environments, the air pressure in the environment is very low. For example, the air pressure at an altitude of 20,000 meters may be as low as 5,000 Pa. Under such low air pressure conditions, it is very easy for discharge or micro-discharge to occur inside the cavity filter, causing sparks and short circuits, causing the performance of related equipment to deteriorate sharply, or even completely fail, thereby greatly reducing its power capacity.
[0003] In the prior art, the following methods are usually used to improve the power capacity of the cavity filter under low pressure conditions:
[0004] The first approach is to start with cavity structure design and topology selection, but this has limited power capacity improvement and will increase size and cost.
[0005] The second is to start with improving the air tightness of the filter. The power capacity can be increased by vacuuming or using a booster system, but this will increase costs and reduce reliability.
[0006] The third is to inject negatively charged gases or inert gases, such as Freon, which can provide extremely high breakdown voltages due to their high adsorption coefficients. However, these gases are toxic, difficult to implement, and prone to safety accidents.
[0007] Therefore, the insufficient power capacity of conventional cavity filters under low air pressure conditions at high altitudes or in high-altitude environments is a technical problem that those skilled in the art urgently need to solve.
[0008] The above information disclosed in the background section is only for enhancing understanding of the background of the present application and therefore it may contain information that does not form the prior art known to a person of ordinary skill in the art. Utility Model Content
[0009] The embodiment of the present application provides a cavity filter to solve the technical problem of insufficient power capacity of a conventional cavity filter under low air pressure conditions at high altitudes or in high-altitude environments.
[0010] A cavity filter according to an embodiment of the present application includes:
[0011] A cavity having an opening at the upper end;
[0012] A resonance rod, wherein the resonance rod has a resonance rod deep hole extending from the top to the bottom, and the resonance rod is fixed on the inner bottom of the cavity;
[0013] A discharge isolation tube, the outer wall of which is fixed to the top of the inner wall of the deep hole of the resonance rod, and the discharge isolation tube is sleeved with the deep hole of the resonance rod;
[0014] A cover plate is fixedly mounted at the opening of the cavity, and the cover plate has a cover plate threaded hole penetrating from top to bottom;
[0015] A tuning screw rod is threadedly connected to the threaded hole of the cover plate, and the bottom end of the tuning screw rod enters into the deep hole of the resonance rod.
[0016] The cavity filter of the embodiment of the present application includes a cavity 1, a resonance rod 4, a discharge isolation tube 8, a cover plate 2, and a tuning screw 6. The key point of the cavity filter of the embodiment of the present application is the discharge isolation tube 8, the outer wall of the discharge isolation tube 8 and the inner wall top of the resonance rod deep hole 41 are fixed, and the discharge isolation tube 8 and the resonance rod deep hole 41 are sleeved. In this way, the cylinder wall of the discharge isolation tube 8 is set in the air position between the lower part of the tuning screw 6 and the top of the resonance rod 4. Since the breakdown field strength of the discharge isolation tube 8 is much higher than that of the air, the cavity filter with the discharge isolation tube 8 is set. Due to the presence of the discharge isolation tube 8, the discharge or micro-discharge phenomenon between the lower part of the tuning screw 6 and the top of the resonance rod 4 is avoided, thereby avoiding the sparking and breaking the circuit, so that the power capacity of the cavity filter is improved, and at the same time, it can also bring the additional effect of reducing the resonance frequency. The power capacity of the cavity filter of the embodiment of the present application is relatively high, and can be applied to low pressure conditions at high altitudes or high altitude environments. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0018] Figure 1 Schematic diagram of a cavity filter according to an embodiment of the present application.
[0019] Reference numerals:
[0020] Cavity 1, cover plate 2, cavity seat 3, resonance rod 4, resonance rod deep hole 41, resonance rod convex edge 42,
[0021] Resonance rod base 5, tuning screw 6, smooth surface 7, discharge isolation cylinder 8, isolation cylinder groove 81. DETAILED DESCRIPTION
[0022] In order to make the technical solutions and advantages in the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than an exhaustive list of all the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.
[0023] Embodiment 1
[0024] like Figure 1 As shown, the cavity filter of the embodiment of the present application includes:
[0025] A cavity 1 having an opening at the upper end;
[0026] A resonance rod 4, wherein the resonance rod 4 has a resonance rod deep hole 41 extending from the top downward, and the resonance rod 4 is fixed on the inner bottom of the cavity;
[0027] A discharge isolation tube 8, the outer wall of the discharge isolation tube 8 and the inner wall top of the resonance rod deep hole 41 are fixed, and the discharge isolation tube 8 and the resonance rod deep hole 41 are sleeved;
[0028] A cover plate 2 is fixedly mounted at the opening of the cavity 1, and the cover plate has a cover plate threaded hole penetrating from top to bottom;
[0029] The tuning screw rod 6 is threadedly connected to the threaded hole of the cover plate, and the bottom end of the tuning screw rod 6 enters into the deep hole 41 of the resonance rod.
[0030] The most prone position for discharge or micro-discharge in a conventional cavity filter is the air between the lower portion of the tuning screw 6 and the top of the resonance rod 4. The cavity filter of the embodiment of the present application comprises a cavity 1, a resonance rod 4, a discharge isolation tube 8, a cover plate 2, and a tuning screw 6. The key point of the cavity filter of the embodiment of the present application is the discharge isolation tube 8, the outer wall of the discharge isolation tube 8 and the top of the inner wall of the resonance rod deep hole 41 are fixed, and the discharge isolation tube 8 and the resonance rod deep hole 41 are sleeved. In this way, the cylinder wall of the discharge isolation tube 8 is set in the air position between the lower portion of the tuning screw 6 and the top of the resonance rod 4. Since the breakdown field strength of the discharge isolation tube 8 is much higher than that of the air, the cavity filter provided with the discharge isolation tube 8 avoids the discharge or micro-discharge phenomenon between the lower portion of the tuning screw 6 and the top of the resonance rod 4 due to the presence of the discharge isolation tube 8, thereby avoiding sparking and breaking the circuit, thereby improving the power capacity of the cavity filter, and at the same time, it can also bring the additional effect of reducing the resonance frequency. The cavity filter of the embodiment of the present application has a high power capacity and can be used under low pressure conditions at high altitudes or high-altitude environments.
[0031] In implementation, such as Figure 1As shown, the top end of the resonance rod 4 has a resonance rod convex edge 42 that opens outwards;
[0032] The top of the discharge isolation tube 8 has an isolation tube groove 81 which is open outward and has a notch facing downward. The isolation tube groove 81 covers the convex edge 42 of the resonance rod. The discharge isolation tube and the isolation tube groove form a discharge isolation tube.
[0033] In this way, the isolation cylinder groove 81 covers the resonance rod convex edge 42. On the one hand, the isolation cylinder groove 81 covers the resonance rod convex edge 42 in a large range, so that the top of the resonance rod 4, that is, the resonance rod convex edge 42, is isolated, and the discharge or micro-discharge phenomenon between the lower part of the tuning screw 6 and the top of the resonance rod 4, that is, the resonance rod convex edge 42 is reduced. On the other hand, even if the discharge isolation cylinder relies only on gravity, it will not be separated from the resonance rod convex edge 42, and the reliability of the installation of the discharge isolation cylinder is achieved.
[0034] In implementation, such as Figure 1 As shown, the discharge isolation tube 8 is a discharge isolation tube made of polytetrafluoroethylene or ceramic material;
[0035] Or the discharge isolation tube 8 is a discharge isolation tube made of ceramic material;
[0036] The thickness of the discharge isolation tube is greater than or equal to 0.6 mm.
[0037] The breakdown field strength of polytetrafluoroethylene is much higher than that of air, so the discharge isolation tube of polytetrafluoroethylene avoids the discharge or micro-discharge phenomenon between the lower part of the tuning screw 6 and the top of the resonance rod 4.
[0038] The breakdown field strength of ceramic material is much higher than that of air, so the discharge isolation tube made of ceramic material avoids the discharge or micro-discharge phenomenon between the lower part of the tuning screw 6 and the top of the resonance rod 4.
[0039] In implementation, such as Figure 1 As shown, a gap is maintained between the bottom end of the tuning screw 6 and the inner wall of the discharge isolation cylinder 8 .
[0040] In implementation, such as Figure 1 As shown, the outer wall of the discharge isolation tube 8 and the inner wall head of the resonance rod deep hole 41 are fixed by bonding, and the isolation tube groove 81 and the resonance rod convex edge 42 are fixed by bonding.
[0041] The bonding fixation method makes the discharge isolation tube stably and reliably fixed to prevent loosening.
[0042] Specifically, the outer wall of the discharge isolation tube 8 and the inner wall head of the resonance rod deep hole 41 are bonded and fixed by AB glue, and the isolation tube groove 81 and the resonance rod convex edge 42 are bonded and fixed by AB glue.
[0043] In implementation, such as Figure 1 As shown, the outer surface of the lower section of the tuning screw 6 entering the cavity is a smooth surface 7.
[0044] In implementation, such as Figure 1 As shown, the inner bottom of the cavity is a cavity seat 3;
[0045] The cavity filter also includes:
[0046] The resonance rod base 5 is fixed to the cavity base 3 ; the resonance rod 4 is fixed on the resonance rod base 5 by means of screw connection.
[0047] In implementation, such as Figure 1 As shown, the cover plate 2 is fixedly installed at the opening of the cavity 1 by screw connection or welding.
[0048] The cover plate and the opening of the cavity 1 can be conveniently and stably connected.
[0049] In the description of the present application and its embodiments, it should be understood that the orientation or positional relationship indicated by the terms "top", "bottom", "height", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0050] In the present application and its embodiments, unless otherwise clearly specified and limited, the terms "set", "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.
[0051] In the present application and its embodiments, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0052] The disclosure above provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described above. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the various specific processes and material examples provided by the present application, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.
[0053] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.
[0054] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.
Claims
1. A cavity filter, characterized in that: include: A cavity (1) having an opening at the upper end; A resonance rod (4), the resonance rod (4) having a resonance rod deep hole (41) extending from the top downward, and the resonance rod (4) is fixed on the inner bottom of the cavity; A discharge isolation tube (8), the outer wall of the discharge isolation tube (8) and the top of the inner wall of the resonance rod deep hole (41) are fixed, and the discharge isolation tube (8) and the resonance rod deep hole (41) are sleeved; A cover plate (2) is fixedly mounted at the opening of the cavity (1), the cover plate having a cover plate threaded hole penetrating from top to bottom; A tuning screw rod (6), wherein the tuning screw rod (6) is threadedly connected to the threaded hole of the cover plate, and the bottom end of the tuning screw rod (6) enters into the deep hole (41) of the resonance rod.
2. The cavity filter according to claim 1, characterized in that: The top end of the resonance rod (4) has a resonance rod convex edge (42) that opens outwards; The top end of the discharge isolation tube (8) has an isolation tube groove (81) which opens outward and has a notch facing downward, the isolation tube groove (81) covers the convex edge (42) of the resonance rod, and the discharge isolation tube and the isolation tube groove form a discharge isolation tube.
3. The cavity filter according to claim 2, characterized in that: The thickness of the discharge isolation tube is greater than or equal to 0.6 mm.
4. The cavity filter according to claim 2, characterized in that: The discharge isolation tube (8) is a discharge isolation tube made of polytetrafluoroethylene or ceramic material; Alternatively, the discharge isolation tube is a discharge isolation tube made of ceramic material.
5. The cavity filter according to claim 3 or 4, characterized in that: A gap is maintained between the bottom end of the tuning screw (6) and the inner wall of the discharge isolation cylinder (8).
6. The cavity filter according to claim 5, characterized in that: The outer wall of the discharge isolation cylinder (8) and the inner wall head of the resonance rod deep hole (41) are fixed by bonding, and the isolation cylinder groove (81) and the resonance rod convex edge (42) are fixed by bonding.
7. The cavity filter according to claim 5, characterized in that: The outer wall of the discharge isolation cylinder (8) and the inner wall head of the resonance rod deep hole (41) are bonded and fixed by AB glue, and the isolation cylinder groove (81) and the resonance rod convex edge (42) are bonded and fixed by AB glue.
8. The cavity filter according to claim 6, characterized in that: The outer surface of the lower section of the tuning screw (6) entering the cavity is a smooth surface.
9. The cavity filter according to claim 8, characterized in that: The inner bottom of the cavity is a cavity seat (3); The cavity filter also includes: The resonance rod base (5) is fixed on the cavity base (3); the resonance rod (4) is fixed on the resonance rod base (5) by means of screw connection.
10. The cavity filter according to claim 9, characterized in that: The cover plate (2) is fixedly mounted at the opening of the cavity (1) by means of screw connection or welding.