CN112751149B

CN112751149B - Cavity filter

Info

Publication number: CN112751149B
Application number: CN202011497331.2A
Authority: CN
Inventors: 吴秀山; 闫树斌; 徐霖; 史浩然; 徐代靖
Original assignee: Zhejiang University of Water Resources and Electric Power
Current assignee: Zhejiang University of Water Resources and Electric Power
Priority date: 2020-12-17
Filing date: 2020-12-17
Publication date: 2022-02-22
Anticipated expiration: 2040-12-17
Also published as: CN112751149A

Abstract

The invention discloses a cavity filter, which comprises a cavity, wherein a plurality of installation cavities are arranged on one side of the cavity, a resonance rod is installed in each installation cavity, a cover plate is hermetically covered on one side of the cavity close to the tops of the installation cavities, a plurality of fixing seats are fixedly installed on the top of the cover plate, adjusting cylinders are fixedly connected to the bottoms of the fixing seats, the adjusting cylinders penetrate through the cover plate, tuning rods are connected to the bottom side of the cover plate, and the tuning rods correspond to the resonance rods one by one. The cavity filter is simple and reasonable in structure, novel in design and simple in operation, effectively solves the technical problems that the traditional cavity filter assembling and debugging mechanism is large in workload, difficult to achieve fine adjustment, large in debugging workload, large in consumed working hours, high in debugging difficulty, high in debugging personnel requirement and high in manufacturing cost, and has high popularization and use values.

Description

Cavity filter

Technical Field

The invention relates to the technical field of filters, in particular to a cavity filter.

Background

The filter is a key device of a modern mobile communication system and is widely applied to wireless communication base stations. The cavity filter is a microwave filter adopting a resonant cavity structure, and one cavity can be equivalent to an inductor and a capacitor connected in parallel, so that a resonant level is formed, and the microwave filtering function is realized. The cavity filter has the advantages of firm structure, wide frequency band, long high-end parasitic pass band, small volume, moderate Q value, flat in-band amplitude-frequency characteristic, stable performance and good heat dissipation performance, and is widely applied to front-end filtering of various large communication base stations to filter out-of-band strong interference signals.

The existing cavity filter can reach the designed performance index only by debugging. Generally, a cavity filter is debugged manually, the cavity filter is connected with a network analyzer, tuning screws are screwed clockwise or anticlockwise, the heights of the tuning screws extending into a cavity are adjusted one by one, then the distance between the tuning screws and a resonance rod is changed, the resonance frequency of a resonance unit of the filter and the coupling amount between the resonance units are changed, the performance change of the cavity filter is observed in real time through the network analyzer, the height of each tuning screw is repeatedly adjusted until the height combination of all the tuning screws meets the performance index of the cavity filter, and finally, a locking nut is screwed to lock the position of each tuning screw. However, in the assembly and debugging process of the cavity filter, the problems of large workload of an assembly and debugging mechanism, difficulty in fine adjustment, large debugging workload, long debugging time, high debugging difficulty, high requirement on debugging personnel and high manufacturing cost often exist, and the actual production requirement is difficult to meet. We therefore improve this and propose a cavity filter.

Disclosure of Invention

In order to solve the problems of large workload of an assembly debugging mechanism, difficulty in fine adjustment, large debugging workload, long debugging time, high debugging difficulty, high requirement on debugging personnel and high manufacturing cost in the traditional cavity filter assembly debugging process, the invention provides the following technical scheme:

the invention relates to a cavity filter, which comprises a cavity, wherein a plurality of installation cavities are arranged on one side of the cavity, a resonance rod is arranged in each installation cavity, a cover plate is hermetically covered on one side of the cavity close to the tops of the installation cavities, a plurality of fixing seats are fixedly arranged on the tops of the cover plates, adjusting cylinders are fixedly connected to the bottoms of the fixing seats, penetrate through the cover plates and are connected to the bottom sides of the cover plates, tuning rods are respectively in one-to-one correspondence with the resonance rods, adjusting air cushions are arranged in the adjusting cylinders, adjusting plates are fixedly connected to the bottom ends of the adjusting air cushions and are fixedly connected to the top ends of the tuning rods, inflating nozzles are fixedly arranged at the top ends of the fixing seats, air pipes are connected to the bottom ends of the inflating nozzles and are communicated with the adjusting air cushions, and shrinkage holes are arranged at the bottom ends of the adjusting cylinders, and the aperture of the shrinkage cavity is slightly larger than the diameter of the tuning rod pair, a spring is installed at the bottom of the inner side of the adjusting cylinder, the spring is sleeved on the outer side of the tuning rod, and the top end of the spring is abutted to the bottom side of the adjusting plate.

As a preferable technical scheme of the invention, the periphery of the top end of the adjusting cylinder is provided with connecting threads, the bottom of the fixed seat is provided with a threaded hole, and the threaded hole can be fixedly connected with the top end of the adjusting cylinder through threads.

As a preferable technical scheme of the invention, the cavity is made by pressing and sintering ceramic powder.

As a preferable technical scheme of the invention, the cover plate is fixedly connected with the cavity through a screw, is made of engineering plastics, and is plated with a metal layer on the surface.

As a preferred technical scheme of the invention, the outer side of the top end of the inflating nozzle is provided with a connecting thread, and the connecting thread is connected with a sealing cover.

Compared with the prior art, the invention has the beneficial effects that:

according to the cavity filter, the inflation pump is connected with the inflation nozzle externally, the adjustment air cushion is inflated, the adjustment air cushion expands and extends after being inflated, the adjustment plate is adjusted downwards quickly, the tuning rod is adjusted quickly, the assembly and debugging efficiency of the cavity filter is improved conveniently, meanwhile, the micro adjustment of the adjustment air cushion is realized by controlling the inflation quantity, and the precise adjustment of the cavity filter is facilitated; the cavity filter is simple and reasonable in structure, novel in design and simple in operation, effectively solves the technical problems of large workload, difficulty in fine adjustment, large debugging workload, high consumed working hours, high debugging difficulty, high requirement on debugging personnel and high manufacturing cost of the traditional cavity filter assembling and debugging mechanism, and has high popularization and use values.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of the overall structure of a cavity filter according to the present invention;

fig. 2 is a schematic view of a fixing base structure of a cavity filter according to the present invention.

In the figure: 1. a cavity; 2. installing a chamber; 3. a resonant rod; 4. a cover plate; 5. a fixed seat; 6. an air charging nozzle; 7. an air tube; 8. an adjusting cylinder; 9. adjusting the air cushion; 10. an adjusting plate; 11. a spring; 12. a tuning rod.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

Example (b): as shown in fig. 1-2, the cavity filter of the present invention comprises a cavity 1, wherein one side of the cavity 1 is provided with a plurality of installation chambers 2, and a resonance rod 3 is installed in each installation chamber 2, the cavity 1 is hermetically covered with a cover plate 4 at a side close to the top of the plurality of installation chambers 2, and the top of the cover plate 4 is fixedly provided with a plurality of fixing bases 5, the bottoms of the fixing bases 5 are fixedly connected with adjusting cylinders 8, the adjusting cylinders 8 penetrate through the cover plate 4, the bottom sides of the cover plate 4 are respectively connected with tuning rods 12, the tuning rods 12 respectively correspond to the resonance rods 3 one by one, adjusting air cushions 9 are installed inside the adjusting cylinders 8, the bottom ends of the adjusting air cushions 9 are fixedly connected with adjusting plates 10, the adjusting plates 10 are fixedly connected with the top ends of the tuning rods 12, the top ends of the fixing bases 5 are fixedly provided with inflation nozzles 6, the bottom ends of the inflation nozzles 6 are connected with air pipes 7, and the air pipe 7 and the adjusting air cushion 9 are communicated with each other, a shrinkage cavity is arranged at the bottom end of the adjusting cylinder 8, the aperture of the shrinkage cavity is slightly larger than the diameter of the tuning rod 12 pair, a spring 11 is arranged at the bottom of the inner side of the adjusting cylinder 8, the spring 11 is sleeved on the outer side of the tuning rod 12, and the top end of the spring 11 is abutted to the bottom side of the adjusting plate 10.

Wherein, the top periphery of adjusting a section of thick bamboo 8 is equipped with connecting thread, the bottom of fixing base 5 is provided with the screw hole, just the screw hole can pass through thread fixed connection with the top of adjusting a section of thick bamboo 8.

Wherein, the cavity 1 is made by pressing and sintering ceramic powder.

The cover plate 4 is fixedly connected with the cavity 1 through a screw, the cover plate 4 is made of engineering plastics, and a metal layer is plated on the surface of the cover plate.

Wherein, the outer side of the top end of the charging connector 6 is provided with a connecting thread and is connected with a sealing cover through the connecting thread.

The working principle is as follows: when the cavity filter is used, the adjusting air cushion 9 is inflated by externally connecting the inflating nozzle 6 with an inflating pump, the adjusting air cushion 9 expands and extends after being inflated, the adjusting plate 10 is quickly adjusted downwards, the tuning rod 12 is quickly adjusted, the assembly and debugging efficiency of the cavity filter is further improved conveniently, meanwhile, the micro-adjustment of the adjusting air cushion 9 is realized by controlling the inflating amount, and the precise adjustment of the cavity filter is further facilitated; the cavity filter is simple and reasonable in structure, novel in design and simple in operation, effectively solves the technical problems of large workload, difficulty in fine adjustment, large debugging workload, high consumed working hours, high debugging difficulty, high requirement on debugging personnel and high manufacturing cost of the traditional cavity filter assembling and debugging mechanism, and has high popularization and use values.

Finally, it should be noted that: in the description of the present invention, it should be noted that the terms "vertical", "upper", "lower", "horizontal", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A cavity filter comprises a cavity (1), wherein one side of the cavity (1) is provided with a plurality of installation chambers (2), and a resonance rod (3) is installed in each installation chamber (2), the cavity (1) is hermetically covered with a cover plate (4) at one side of the top close to the installation chambers (2), the top of the cover plate (4) is fixedly provided with a plurality of fixing seats (5), the bottoms of the fixing seats (5) are fixedly connected with adjusting cylinders (8), the adjusting cylinders (8) penetrate through the cover plate (4), tuning rods (12) are connected to the bottom side of the cover plate (4), the tuning rods (12) respectively correspond to the resonance rods (3) one by one, adjusting air cushions (9) are installed inside the adjusting cylinders (8), and adjusting plates (10) are fixedly connected to the bottom ends of the adjusting air cushions (9), just regulating plate (10) and the top fixed connection of tuning rod (12), the top fixed mounting of fixing base (5) has charging connector (6), the bottom of charging connector (6) is connected with trachea (7), just trachea (7) and regulation air cushion (9) switch-on each other, the bottom of adjusting a section of thick bamboo (8) is provided with the shrinkage cavity, just the aperture of shrinkage cavity slightly is greater than the diameter of tuning rod (12), spring (11) are installed to the inboard bottom of adjusting a section of thick bamboo (8), the outside at tuning rod (12) is established in spring (11) cover, just spring (11) top offsets the setting with the bottom side of regulating plate (10).

2. The cavity filter according to claim 1, wherein the top end of the adjusting cylinder (8) is provided with a connecting thread at its periphery, the bottom of the fixing seat (5) is provided with a threaded hole, and the threaded hole can be fixedly connected with the top end of the adjusting cylinder (8) by a thread.

3. A cavity filter according to claim 1, wherein the cavity (1) is made by pressing and sintering ceramic powder.

4. The cavity filter according to claim 1, wherein the cover plate (4) is fixedly connected with the cavity (1) through screws, and the cover plate (4) is made of engineering plastics and is plated with a metal layer on the surface.

5. The cavity filter according to claim 1, wherein the top end of the charging connector (6) is provided with a connecting thread on the outer side, and a sealing cover is connected with the connecting thread.