Self-locking type tuning cavity filter

Abstract

The invention discloses a self-locking type tuning cavity filter which comprises a cavity, a resonator, a cover plate and an input and output connector, the resonator is arranged in the cavity, the cover plate covers the opening end of the cavity, the input and output connector is arranged on the cavity or the cover plate and connected with the resonator, and the cavity or the cover plate is connected with the input and output connector. Each tuning screw is provided with a connecting section and a deformation section, and the deformation sections have outward deformation force; a plurality of screw holes are formed in the cavity or the cover plate; when the tuning screw rod is arranged in the screw hole, the connecting section and the resonator are oppositely arranged, and at least part of the deformation section is located in the screw hole; through the structure, a nut for locking can be omitted, the tuning screw rod has a certain self-locking function, the tuning screw rod has an effect of never loosening during matched welding, the weight of the cavity filter is reduced, the stability of the cavity filter is improved, and the use requirement is met.

Description

Technical Field

[0001] The invention relates to the field of cavity filters, and in particular to a self-locking tuned cavity filter. Background Art

[0002] Cavity filter is a very important filter. Compared with filters of other properties, it has the advantages of firm 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. Figure 1-Figure 2 The filter structure of a communication base station is usually composed of a cavity, a resonator, a cover plate, a tuning screw, a tuning nut and an input and output connector. The tuning method of the traditional filter is to prefabricate threaded holes on the product cover plate or cavity, and pre-thread the tuning screw through the tuning nut. The tuning screw is rotated through the thread on the cover plate and extends into the cavity. The tuning screw is repeatedly screwed according to the changes in the vector network analyzer graph until the performance of the filter meets the design requirements. Finally, the tuning nut is tightened, and the tuning screw is fixed by the friction between the tuning nut and the cover plate, and finally UV glue is applied to prevent loosening. However, the anti-loosening effect of this tuning screw is poor. Under temperature cycle and vibration impact, it is easy to loosen and move. The function of the tuning nut is only to prevent loosening, which invisibly increases the product quality, and the application of UV glue also increases the product process and cost. Therefore, a self-locking tuned cavity filter is urgently needed to solve the above problems. Summary of the invention

[0003] 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 self-locking tuned cavity filter.

[0004] An embodiment of the present invention solves the technical problem by adopting a technical solution: a self-locking tuned cavity filter, comprising a cavity, a resonator, a cover plate and an input-output connector, wherein the resonator is arranged in the cavity, the cover plate is arranged on the open end of the cavity, the input-output connector is installed on the cavity or the cover plate and connected to the resonator, and further comprises a plurality of tuning screws having a connecting section and a deformation section, wherein the deformation section has an outward deformation force;

[0005] The cavity or the cover plate is provided with a plurality of screw holes;

[0006] When the tuning screw is installed in the screw hole, the connecting section and the resonator are arranged opposite to each other, and at least a part of the deformation section is located in the screw hole.

[0007] As one of the preferred embodiments of the present invention, the tuning screw is provided with a plurality of forks that deform outwardly to form deformation sections.

[0008] As one of the preferred embodiments of the present invention, the number of slits is two.

[0009] As one of the preferred embodiments of the present invention, the angle α between the fork and the central axis of the tuning screw is 0°<α<7.5°.

[0010] As one of the preferred embodiments of the present invention, the length of the connecting section is A, the thickness of the cavity or the cover plate is a, and A>a.

[0011] As one of the preferred embodiments of the present invention, the deformation section is welded in the screw hole.

[0012] As one of the preferred embodiments of the present invention, an adjusting groove is provided in the tuning screw for driving the tuning screw to rotate.

[0013] As one of the preferred embodiments of the present invention, the adjusting groove is configured as a hexagonal groove.

[0014] As one of the preferred embodiments of the present invention, the adjusting groove penetrates along the length direction of the tuning screw and also includes a pipe plug arranged in the adjusting groove for closing the lower end opening of the adjusting groove.

[0015] As one of the preferred embodiments of the present invention, a mounting platform is provided on the inner wall of the cavity or the cover plate, a threaded groove is provided on the mounting platform, a through hole is provided on the resonator, and a bolt is also provided which passes through the through hole and is connected to the threaded groove.

[0016] The beneficial effects of the present invention are as follows: a self-locking tuned cavity filter comprises a cavity, a resonator, a cover plate and an input-output connector, the resonator is arranged in the cavity, the cover plate is covered on the open end of the cavity, the input-output connector is installed on the cavity or the cover plate and is connected to the resonator, and also comprises a plurality of tuning screws with a connecting section and a deformation section, the deformation section has an outward deformation force; a plurality of screw holes are arranged on the cavity or the cover plate; when the tuning screw is installed in the screw hole, the connecting section is arranged relative to the resonator, and at least part of the deformation section is located in the screw hole; through the above structure, not only the nut used for anti-loosening can be eliminated, but also the tuning screw has a certain self-locking function, and when combined with welding, it has the effect of never loosening, reducing the weight of the cavity filter while improving the stability of the cavity filter, meeting the use requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] 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:

[0018] Figure 1 is an exploded view of an existing cavity filter;

[0019] Figure 2 is a cross-sectional view of an existing cavity filter;

[0020] Figure 3 An exploded view of a self-locking tuned cavity filter;

[0021] Figure 4 A cross-sectional view of a self-locking tuned cavity filter;

[0022] Figure 5 It is the production flow chart of the tuning screw in the present invention. DETAILED DESCRIPTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Reference Figures 3 to 5 A self-locking tuned cavity filter comprises a cavity 10, a resonator 20, a cover plate 30 and an input / output connector, wherein the resonator 20 is arranged in the cavity 10, the cover plate 30 is arranged to cover the open end of the cavity 10, the input / output connector is mounted on the cavity 10 or the cover plate 30 and connected to the resonator 20, and further comprises a plurality of tuning screws 40 having a connecting section 41 and a deformation section 42, wherein the deformation section 42 has an outward deformation force;

[0028] A plurality of screw holes 50 are provided on the cavity 10 or the cover plate 30;

[0029] When the tuning screw 40 is installed in the screw hole 50 , the connecting section 41 is arranged opposite to the resonator 20 , and at least a portion of the deformation section 42 is located in the screw hole 50 .

[0030] ① In the present invention, reference is made to Figure 3-Figure 5 As a preferred embodiment of the tuning screw 40, the tuning screw 40 is manufactured by a metal drawing process (by applying external force to cause the metal material to undergo plastic deformation, so that it undergoes tensile deformation, thereby obtaining a desired shape and size; during the stretching process, the metal material undergoes plastic flow, so that its cross-sectional area decreases and its length increases, accompanied by changes in stress and strain. By controlling parameters such as the stretching force, deformation speed and temperature, the stretching processing of profiles of different sizes and shapes can be achieved). Specifically:

[0031] 1)Reference Figure 5 (a) and (e) are integrally drawn into a metal profile and an adjustment groove 70 therein through a metal drawing process. The adjustment groove 70 can drive the tuning screw 40 to rotate when driven by a tool of a corresponding shape. As a preferred embodiment of the adjustment groove 70, the adjustment groove 70 is configured as a hexagonal socket.

[0032] 2)Reference Figure 5 (b) turning a thread on the outer wall of the metal profile;

[0033] 3)Reference Figure 5 (c), the adjustment groove 70 is Figure 5 The adjustment groove 70 is drawn integrally with the metal profile in the process (a), and penetrates along the length direction of the tuning screw 40. In order to avoid electromagnetic interference, a pipe plug 80 is also provided in the adjustment groove 70 to close the lower end opening of the adjustment groove 70 (i.e., the end close to the resonator 20).

[0034] 4)Reference Figure 5 (d) by cutting or the like, at least two slits 60 are formed in the deformation section 42 of the tuning screw 40 , and the slits 60 are deformed toward the outer shape so that the outer diameter of the deformation section 42 of the tuning screw 40 is larger than the outer diameter of the connecting section 41 of the tuning screw 40 .

[0035] ②Reference Figure 3-Figure 5 A self-locking tuned cavity filter provided by the present invention comprises a cavity 10, a resonator 20, a cover plate 30 and an input / output connector (not shown). The resonator 20 is arranged in the cavity 10, the cover plate 30 is arranged to cover the open end of the cavity 10, and the input / output connector is installed on the cavity 10 or the cover plate 30 and connected to the resonator 20. The assembly and tuning process of the cavity filter is described by taking the screw hole 50 and the tuning screw 40 installed on the cover plate 30 as an example:

[0036] 1) In some embodiments, a mounting platform 91 is provided on the inner wall of the cavity 10 or the cover plate 30, and a threaded groove 92 is provided on the mounting platform 91. A through hole 93 is provided on the resonator 20, and a bolt 94 is also provided, which is passed through the through hole 93 and connected to the threaded groove 92. During assembly, the through hole 93 on the resonator 20 and the threaded groove 92 on the mounting platform 91 are first arranged relative to each other, and then the rod of the bolt 94 is passed through the through hole 93 and connected to the threaded groove 92, and the head of the bolt 94 abuts against the resonator 20. Furthermore, a receiving groove is provided in the resonator 20, and the head of the bolt 94 is accommodated in the receiving groove to avoid affecting the tuning.

[0037] 2) The cover plate 30 is then connected to the cavity 10 by welding and / or bolting;

[0038] 3) The prepared tuning screw 40 is screwed into the screw hole 50 with the connecting section 41 facing the screw hole 50, so that the state of the tuning screw 40 changes from Figure 4 (a) Gradually rotate into Figure 4 (b) state, during the screwing-in process, friction is generated between the threads of the tuning screw 40 and the screw hole 50, thereby generating friction force between the tuning screw 40 and the screw hole 50. When the screwing-in size increases, the friction force not only needs to overcome the friction force between the tuning screw 40 and the screw hole 50, but also needs to overcome the elastic deformation caused by the fork 60 on the tuning screw 40 (an inclined torque will be formed between the forks 60). As the screwing-in size becomes deeper, the elastic deformation force will become greater and greater. The thread width does not need to bear the load, and its friction force is sufficient to fix the tuning screw 40, and no relative displacement will occur due to movement, turnover, etc.

[0039] 4) Finally, the junction of the tuning screw 40 and the screw hole 50 is heated by laser radiation to melt the workpieces, forming a specific molten pool and permanently combining them together.

[0040] ③ In some embodiments, refer to Figure 3-Figure 5 The tuning screw 40 is provided with a plurality of slits 60 that deform outward to form a deformation section 42; preferably, two slits 60 are provided.

[0041] ④ In some embodiments, reference Figure 5 , the angle α between the fork 60 and the central axis of the tuning screw 40 is 0°<α<7.5°.

[0042] ⑤ In some embodiments, reference Figure 5 , the length of the connecting section 41 is A, the thickness of the cavity 10 or the cover plate 30 is a, A>a; this setting can ensure that the connecting section 41 on the tuning screw 40 has sufficient length to change the distance between it and the resonator 20 to meet the adjustment requirements of various resonant frequencies.

[0043] ⑥ The advantage of the present invention is that: through the above structure, not only the nut used to prevent loosening can be eliminated, but also the tuning screw has a certain self-locking function. When combined with welding, it has the effect of never loosening, reducing the weight of the cavity filter while improving the stability of the cavity filter to meet the use requirements.

[0044] 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 self-locking tuned cavity filter, comprising a cavity (10), a resonator (20), a cover plate (30) and an input / output connector, wherein the resonator (20) is arranged in the cavity (10), the cover plate (30) is arranged to cover the open end of the cavity (10), and the input / output connector is installed on the cavity (10) or the cover plate (30) and connected to the resonator (20), characterized in that: It also includes a plurality of tuning screws (40) having connecting sections (41) and deformation sections (42), wherein the deformation sections (42) have an outward deformation force; The cavity (10) or the cover plate (30) is provided with a plurality of screw holes (50); When the tuning screw (40) is installed in the screw hole (50), the connecting section (41) and the resonator (20) are arranged opposite to each other, and at least a portion of the deformation section (42) is located in the screw hole (50).

2. A self-locking tuned cavity filter according to claim 1, characterized in that: The tuning screw (40) is provided with a plurality of forks (60) deforming outward to form the deformation section (42).

3. A self-locking tuned cavity filter according to claim 2, characterized in that: The number of the slits (60) is two.

4. A self-locking tuned cavity filter according to claim 2, characterized in that: The angle α between the fork (60) and the central axis of the tuning screw (40) is 0°<α<7.5°.

5. The self-locking tuned cavity filter according to claim 1, characterized in that: The length of the connecting section (41) is A, the thickness of the cavity (10) or the cover plate (30) is a, and A>a.

6. The self-locking tuned cavity filter according to claim 1, characterized in that: The deformation section (42) is welded in the screw hole (50).

7. The self-locking tuned cavity filter according to claim 1, characterized in that: The tuning screw (40) has an adjustment slot (70) therein for driving the tuning screw (40) to rotate.

8. A self-locking tuned cavity filter according to claim 7, characterized in that: The adjustment groove (70) is configured as a hexagonal groove.

9. The self-locking tuned cavity filter according to claim 7, characterized in that: The adjusting groove (70) penetrates along the length direction of the tuning screw (40), and also includes a pipe plug (80) arranged in the adjusting groove (70) for closing the lower end opening of the adjusting groove (70).

10. The self-locking tuned cavity filter according to claim 1, characterized in that: A mounting platform (91) is provided on the inner side wall of the cavity (10) or the cover plate (30), a threaded groove (92) is provided on the mounting platform (91), a through hole (93) is provided on the resonator (20), and a bolt (94) is provided in the through hole (93) and connected to the threaded groove (92).

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