Miniaturized coaxial cavity filter

Abstract

The invention discloses a miniaturized coaxial cavity filter. The miniaturized coaxial cavity filter comprises a cavity, a cover plate, a resonator, a tuning assembly and an input / output connector, a mounting opening is formed in the top of the cavity; the cover plate is arranged at the mounting opening, and a plurality of bosses are integrally stretched and formed on the inner side wall of the cover plate; the resonator is welded on the boss; the tuning assembly is arranged at the bottom of the cavity and is opposite to the resonator; the input and output connector is arranged on the cavity and is connected with the resonator; through the above structure, the profile height of the cavity filter can be reduced, the resonator is prevented from displacement, deformation or loosening at a high temperature, the stability of the cavity filter is improved, the application range of the cavity filter is widened, and the use requirements are met.

Description

Technical Field

[0001] The invention relates to the field of filters, and in particular to a miniaturized coaxial cavity filter. Background Art

[0002] Cavity filter is a very important filter. Compared with filters of other properties, it has the advantages of solid structure, stable and reliable performance, small size, moderate Q value, long high-end parasitic passband and good heat dissipation performance. It can be used for higher power and frequency.

[0003] Existing communication base station cavity filters are usually composed of a cavity, a resonator, a cover plate, a tuning screw, a tuning nut and an input and output connector. There are three ways to connect the resonator to the cavity or cover plate: 1. Figure 1 , the resonator is integrated with the screw and then locked on the cavity; 2. Figure 1 , the resonator is welded on the cavity; 3. Refer to Figure 1 The resonator and the screw are split structures, and the resonator is locked to the cavity by the screw. However, the filters with the above structures cannot simultaneously meet the requirements of no displacement, deformation or loosening under high temperature conditions, and lower profile height, which limits the performance or use environment of the filter and reduces the market competitiveness of the filter.

[0004] Secondly, the tuning component is arranged on the cover plate, especially when using a tuning screw and a tuning nut, in order to ensure a good threaded connection effect between the threaded hole on the cover plate and the tuning screw, there are certain requirements for the effective depth of the threaded hole, which in turn requires a certain thickness of the cover plate, limiting the cross-sectional height of the cavity filter; therefore, a miniaturized coaxial cavity filter is urgently needed to solve the above problems. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a miniaturized coaxial cavity filter.

[0006] The technical solution adopted by an embodiment of the present invention to solve the technical problem is: a miniaturized coaxial cavity filter, including a cavity, a cover plate, a resonator, a tuning component and an input and output connector;

[0007] The top of the cavity is provided with a mounting opening;

[0008] The cover plate is arranged at the installation opening and a plurality of bosses are integrally formed by stretching on the inner side wall;

[0009] The resonator is welded to the boss;

[0010] The tuning component is arranged at the bottom of the cavity and is arranged opposite to the resonator;

[0011] The input and output connector is arranged on the cavity and connected to the resonator.

[0012] As one of the preferred embodiments of the present invention, a plurality of coupling ribs located between two adjacent resonators are integrally formed by stretching on the inner side wall of the cover plate.

[0013] As one of the preferred embodiments of the present invention, a first hollow groove communicating with the outer side wall of the cover plate is provided on the coupling partition rib.

[0014] As one of the preferred embodiments of the present invention, a second hollow groove communicating with the outer side wall of the cover plate is provided on the boss.

[0015] As one of the preferred embodiments of the present invention, a plurality of coupling components are arranged on two adjacent resonators to form a capacitive structure.

[0016] As one of the preferred embodiments of the present invention, the coupling component includes a first connecting plate arranged on one of two adjacent resonators and a second connecting plate arranged on the other of the two adjacent resonators, and the first connecting plate and the second connecting plate are close to each other but not in contact.

[0017] As one of the preferred embodiments of the present invention, a plug-in slot is provided on the boss, and a plug-in column plugged into the plug-in slot is provided on the resonator.

[0018] As one of the preferred embodiments of the present invention, a connecting column is arranged on the inner bottom surface of the cavity, and the cover plate is connected to the connecting column and / or the cavity by means of set screws.

[0019] As one of the preferred embodiments of the present invention, the tuning assembly includes a tuning screw and a tuning nut. A threaded hole is provided at the bottom of the cavity. The tuning screw is threadedly connected in the threaded hole and one end is arranged opposite to the resonator and the other end extends outside the cavity. The tuning nut is threadedly connected to the other end of the tuning screw and abuts against the cavity.

[0020] As one of the preferred embodiments of the present invention, a plurality of electroplating exchange holes are provided on the cavity and / or the cover plate.

[0021] The beneficial effects of the present invention are as follows: a miniaturized coaxial cavity filter comprises a cavity, a cover plate, a resonator, a tuning component and an input-output connector; the top of the cavity has a mounting opening; the cover plate is arranged at the mounting opening and a plurality of bosses are integrally stretched and formed on the inner wall; the resonator is welded on the boss; the tuning component is arranged at the bottom of the cavity and is arranged opposite to the resonator; the input-output connector is arranged on the cavity and connected to the resonator; the above structure can reduce the cross-sectional height of the cavity filter, and also avoid the displacement, deformation or loosening of the resonator under high temperature conditions, which is beneficial to improving the stability and application range of the cavity filter and meeting the use requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 It is a structural schematic diagram of an existing cavity filter;

[0024] Figure 2 It is a first structural schematic diagram of a miniaturized coaxial cavity filter;

[0025] Figure 3 is a second structural schematic diagram of a miniaturized coaxial cavity filter;

[0026] Figure 4 An exploded view of a miniaturized coaxial cavity filter;

[0027] Figure 5 is a cross-sectional view of a miniaturized coaxial cavity filter;

[0028] Figure 6 Schematic diagram of the structure of the cover plate and the resonator. DETAILED DESCRIPTION

[0029] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0030] In the description of the present invention, the meaning of "above", "below", "exceed", etc. is not inclusive of the number itself, and the meaning of "above", "below", "within", etc. is inclusive of the number itself. If there is a description of "first" or "second", it is only used to distinguish the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0031] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply 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 invention.

[0032] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, they can be directly connected or indirectly connected through an intermediate medium; they can be fixedly connected or detachably connected or integrally formed; they can be mechanically connected; they can be the internal connection of two elements or the interaction relationship between two elements. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0033] Reference Figures 2 to 6 , a miniaturized coaxial cavity filter, comprising a cavity 10, a cover plate 20, a resonator 30, a tuning component 40 and an input and output connector 50;

[0034] The top of the cavity 10 has a mounting opening 11;

[0035] The cover plate 20 is arranged at the installation opening 11 and has a plurality of bosses 21 integrally formed by stretching on the inner wall;

[0036] The resonator 30 is welded on the boss 21;

[0037] The tuning component 40 is disposed at the bottom of the cavity 10 and is arranged opposite to the resonator 30;

[0038] The input / output connector 50 is disposed on the cavity 10 and connected to the resonator 30 .

[0039] In the present invention, during production, a plurality of bosses 21 are integrally formed on the cover plate 20 by a sheet metal stretching process. In some embodiments, a plurality of coupling ribs 22 located between two adjacent resonators 30 are integrally stretched and formed on the inner wall of the cover plate 20 by a sheet metal stretching process, and the cavity 10 is formed by sheet metal stamping, bending and other processes; during assembly, the resonator 30 is first placed on the boss 21, and welded to the boss 21 as a whole by laser welding and other processes, and then the cover plate 20 and the resonator 30 are integrally placed in the cavity 10. In some embodiments, a connecting column 81 is provided on the inner bottom surface of the cavity 10, and the cover plate 20 is connected to the connecting column 81 and / or the cavity 10 by a set screw 82 to achieve assembly between the cover plate 20 and the cavity 10, and then the overall electroplating is performed; finally, the tuning component 40 is installed in the cavity The bottom of 10 (the side arranged opposite to the installation port 11) is adjusted and screwed by repeatedly adjusting the tuning component 40 according to the changes in the vector network analyzer graph until the performance of the filter meets the design requirements; since the resonator 30 is welded to the cover plate 20 and the tuning component 40 is installed on the cavity 10 to form a coaxial structure, there is no need to open a threaded hole 43 on the cover plate 20 (in the embodiment where the tuning component 40 is set as a tuning screw 41 and a tuning nut 42), and there is no need to increase the thickness of the cover plate 20 to meet the effective depth of the threaded hole 43, that is, the thickness of the cover plate 20 can be reduced; the advantage of the present invention is that: the above structure can reduce the cross-sectional height of the cavity filter, and at the same time, it also avoids the displacement, deformation or loosening of the resonator under high temperature conditions, which is beneficial to improving the stability and application range of the cavity filter and meeting the use requirements.

[0040] In some embodiments, a first hollow groove 61 connected to the outer wall of the cover plate 20 is provided on the coupling partition rib 22; by providing the first hollow groove 61 on the coupling partition rib 22 to make the coupling partition rib 22 a hollow structure, it can not only save material costs but also reduce the weight of the cover plate 20.

[0041] In some embodiments, a second hollow groove 62 connected to the outer wall of the cover plate 20 is provided on the boss 21; by providing the second hollow groove 62 on the boss 21, the boss 21 is made into a hollow structure, which can not only save material costs but also reduce the weight of the cover plate 20; and by providing the boss 21, materials with different expansion coefficients can be selected to achieve the effect of compensating for temperature drift.

[0042] In some embodiments, a plurality of coupling components 70 are provided on two adjacent resonators 30 to form a capacitive structure; preferably, the coupling component 70 includes a first connecting plate 71 provided on one of the two adjacent resonators 30 and a second connecting plate 72 provided on the other of the two adjacent resonators 30, and the first connecting plate 71 and the second connecting plate 72 are close to each other but not in contact; specifically, one or more groups of non-intersecting sheet metal connecting plates are extended between two adjacent resonators 30 to form a capacitive structure, and the angle and structure of the connecting plates are not limited. The capacitive structure has very good flexibility and can be arranged in different positions to achieve the same performance requirements as the flying rod and improve the proximal suppression of the passband; further, the capacitive structure of the present invention is parasitic on the sides of any two groups of resonators, and the position and shape can be in various forms, which has the advantage of flexibility and versatility.

[0043] In some embodiments, a plug-in slot 23 is provided on the boss 21, and a plug-in column 31 inserted into the plug-in slot 23 is provided on the resonator 30; the resonator 30 is pre-positioned on the boss 21 by the cooperation of the plug-in column 31 and the plug-in slot 23, which is convenient for subsequent adjustment of the capacitive coupling component and for welding the resonator 30 to the boss 21.

[0044] In some embodiments, the tuning assembly 40 includes a tuning screw 41 and a tuning nut 42. A threaded hole 43 is provided at the bottom of the cavity 10. The tuning screw 41 is threadedly connected in the threaded hole 43 and one end is arranged opposite to the resonator 30 and the other end extends outside the cavity 10. The tuning nut 42 is threadedly connected to the other end of the tuning screw 41 and abuts against the cavity 10.

[0045] In some embodiments, a plurality of electroplating exchange holes 90 are provided on the cavity 10 and / or the cover plate 20, which are used to exchange the electroplating solution during electroplating, and the electroplating exchange holes 90 are sealed after the electroplating is completed.

[0046] Of course, the present invention is not limited to the above-mentioned embodiments, and those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications and substitutions are all included in the scope defined by the claims of this application.

Claims

1. A miniaturized coaxial cavity filter, characterized in that: It comprises a cavity (10), a cover plate (20), a resonator (30), a tuning component (40) and an input and output connector (50); The top of the cavity (10) is provided with a mounting opening (11); The cover plate (20) is arranged at the installation opening (11) and has a plurality of bosses (21) integrally formed by stretching on the inner side wall; The resonator (30) is welded on the boss (21); The tuning component (40) is arranged at the bottom of the cavity (10) and is arranged opposite to the resonator (30); The input-output connector (50) is arranged on the cavity (10) and connected to the resonator (30).

2. A miniaturized coaxial cavity filter according to claim 1, characterized in that: A plurality of coupling ribs (22) located between two adjacent resonators (30) are integrally formed by stretching on the inner side wall of the cover plate (20).

3. A miniaturized coaxial cavity filter according to claim 2, characterized in that: The coupling rib (22) is provided with a first hollow groove (61) which is in communication with the outer side wall of the cover plate (20).

4. The miniaturized coaxial cavity filter according to claim 1, characterized in that: The boss (21) is provided with a second hollow groove (62) which is in communication with the outer side wall of the cover plate (20).

5. The miniaturized coaxial cavity filter according to claim 1, characterized in that: A plurality of coupling components (70) are arranged on two adjacent resonators (30) to form a capacitive structure.

6. The miniaturized coaxial cavity filter according to claim 5, characterized in that: The coupling component (70) comprises a first connecting plate (71) arranged on one of two adjacent resonators (30) and a second connecting plate (72) arranged on the other of the two adjacent resonators (30), wherein the first connecting plate (71) and the second connecting plate (72) are close to each other but not in contact.

7. The miniaturized coaxial cavity filter according to claim 1, characterized in that: The boss (21) is provided with a plug-in slot (23), and the resonator (30) is provided with a plug-in column (31) plugged into the plug-in slot (23).

8. The miniaturized coaxial cavity filter according to claim 1, characterized in that: A connecting column (81) is provided on the inner bottom surface of the cavity (10), and the cover plate (20) is connected to the connecting column (81) and / or the cavity (10) via a set screw (82).

9. The miniaturized coaxial cavity filter according to claim 1, characterized in that: The tuning assembly (40) comprises a tuning screw (41) and a tuning nut (42); a threaded hole (43) is provided at the bottom of the cavity (10); the tuning screw (41) is threadedly connected in the threaded hole (43) and one end of the tuning screw (41) is arranged opposite to the resonator (30) and the other end extends outside the cavity (10); the tuning nut (42) is threadedly connected to the other end of the tuning screw (41) and abuts against the cavity (10).

10. The miniaturized coaxial cavity filter according to claim 1, characterized in that: A plurality of electroplating exchange holes (90) are provided on the cavity (10) and / or the cover plate (20).

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