Tuning component for cavity filter and cavity filter
By using a combination design of metal tuning screw, high-temperature resistant plastic fixture and metal fastening screw in the cavity filter, the problem of distance changes caused by the ceramic resonant disk is solved, and the cavity filter is realized Stable and reliable tuning components.
Patent Information
- Application Number
- CN201910540335.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2019-06-20
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2039-06-20
AI Technical Summary
In the tuning components of existing cavity filters, the ceramic resonant disk is prone to brittle cracking and difficult to combine with the tuning screw. Due to the high thermal expansion coefficient of the tuning screw material, temperature changes lead to a change in the distance between the resonant disk and the resonator, which affects the normal filter. use.
Using metal tuning screws, high-temperature-resistant plastic fixtures and metal fastening screws, the hollow part and through-hole design of the plastic fixtures can achieve a stable combination of the resonant disk and the tuning screw, and use metal material with low thermal expansion coefficient to tune. The screw reduces the distance changes due to temperature changes.
The stable combination of the resonant disk and the tuning screw is achieved, which avoids the brittle cracking problem of the resonant disk, and reduces the passive change of the distance between the resonant disk and the resonator when the temperature changes, ensuring the normal use and reliability of the cavity filter.
Smart Images
Figure CN110148823B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of communication technology, and in particular to a tuning component for a cavity filter and a cavity filter. Background Art
[0002] A tuning assembly for a cavity filter in the prior art includes a tuning screw disposed on a cover plate of the cavity and a resonant disk located in the cavity and fixedly connected to the bottom of the tuning screw. By adjusting the position of the tuning screw, the distance between the resonant disk and the resonator located in the cavity can be changed, thereby achieving the purpose of tuning the cavity filter. However, since the resonant disk is made of brittle ceramic material, when the resonant disk is combined with the tuning screw, the resonant disk is prone to brittle cracking, which makes the combination difficult and the quality unstable. Moreover, since the tuning screw is made of a plastic material with a high thermal expansion coefficient, when there are large changes in high and low temperatures, the distance between the resonant disk and the resonator will change passively, thereby affecting the normal use of the cavity filter. Summary of the invention
[0003] The object of the present invention is to provide a tuning assembly for a cavity filter, which can easily realize a stable combination between a resonator and a tuning screw, and will not affect the normal use of the cavity filter due to temperature changes.
[0004] Another object of the present invention is to provide a cavity filter that can easily achieve a stable combination between the resonator and the tuning screw, and will not affect the normal use of the cavity filter due to temperature changes.
[0005] In order to achieve the above-mentioned purpose, the present invention provides a tuning component for a cavity filter, characterized in that it includes a tuning screw made of metal material, a resonance disk, a plastic fixed body and a fastening screw, the middle part of the resonance disk is formed with a hollow portion, the plastic fixed body is injection molded in the hollow portion, the middle part of the plastic fixed body is formed with a through hole, the bottom of the tuning screw is arranged on the plastic fixed body, the tuning screw is formed with a threaded hole corresponding to the through hole of the plastic fixed body, and the fastening screw is passed through the through hole and then screwed into the threaded hole of the tuning screw.
[0006] Preferably, the tuning screw is made of brass.
[0007] Preferably, the resonant disk is made of ceramic material.
[0008] Preferably, the plastic fixing body is made of high temperature resistant material.
[0009] Preferably, the plastic fixing body is made of polyetherimide.
[0010] Preferably, a flange portion is formed at the upper end of the plastic fixing body, and the flange portion is combined with the upper surface of the resonance disk.
[0011] Preferably, the fastening screw is made of metal, and the portion of the fastening screw that cooperates with the threaded hole is coated with glue to prevent loosening in the circumferential direction.
[0012] Preferably, the portion where the fastening screw cooperates with the threaded hole is coated with glue for approximately 180 degrees in the circumferential direction to prevent loosening.
[0013] In order to achieve the other purpose mentioned above, the present invention provides a cavity filter, including a cavity, a resonator and a tuning assembly, the resonator is fixed in the cavity, the tuning assembly is as described above, the tuning screw is adjustably arranged on the cover plate of the cavity, the resonance disk is located in the cavity and corresponds to the resonator, and the distance between the resonance disk and the resonator can be changed by adjusting the tuning screw.
[0014] Preferably, the cavity filter further comprises a tuning nut disposed on a cover plate of the cavity, the tuning screw is threadably matched with the tuning nut, and the tightening torque of the tuning nut is greater than 15 kgf.cm.
[0015] Compared with the prior art, the middle part of the resonant disk of the tuning assembly of the present invention is formed with a hollow part, a plastic fixing body is injection molded at the hollow part, a tuning screw is arranged on the plastic fixing body, the plastic fixing body is provided with a through hole, the tuning screw is provided with a threaded hole corresponding to the through hole, and the fastening screw is screwed and fixed in the threaded hole of the tuning screw after passing through the through hole, so that the resonant disk and the tuning screw can be easily and stably combined through the plastic fixing body and the fastening screw, avoiding the problem of brittle cracking of the resonant disk. Moreover, since the tuning screw in the present invention uses a metal material with a low thermal expansion coefficient, it can basically avoid the passive change of the distance between the resonant disk and the resonator in the case of large changes in high and low temperatures, and will not affect the normal use of the cavity filter. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the three-dimensional structure of a tuning component for a cavity filter according to an embodiment of the present invention.
[0017] Figure 2 yes Figure 1 A cross-sectional schematic diagram of a tuning component for a cavity filter is shown.
[0018] Figure 3 yes Figure 1 Schematic diagram of the exploded structure of the tuning components for the cavity filter.
[0019] Figure 4It is a schematic diagram of the structure of a cavity filter according to an embodiment of the present invention. DETAILED DESCRIPTION
[0020] In order to explain the content, structural features, achieved objectives and effects of the present invention in detail, the following is a detailed description in conjunction with the implementation modes and the accompanying drawings.
[0021] See also Figures 1 to 3 The present invention discloses a tuning component 100 for a cavity filter, including a tuning screw 10 made of a metal material, a resonance disk 20, a plastic fixed body 30 and a fastening screw 40. A hollow portion 21 is formed in the middle of the resonance disk 20, the plastic fixed body 30 is injection molded in the hollow portion 21, a through hole 31 is formed in the middle of the plastic fixed body 30, the bottom of the tuning screw 10 is arranged on the plastic fixed body 30, the tuning screw 10 is formed with a threaded hole 11 corresponding to the through hole 31 of the plastic fixed body 30, and the fastening screw 40 is screwed and fixed in the threaded hole 11 of the tuning screw 10 after passing through the through hole 31.
[0022] The middle part of the resonant disk 20 of the tuning assembly 100 of the present invention is formed with a hollow part 21, a plastic fixing body 30 is injection molded at the hollow part 21, a tuning screw 10 is arranged on the plastic fixing body 30, the plastic fixing body 30 is provided with a through hole 31, the tuning screw 10 is provided with a threaded hole 11 corresponding to the through hole 31, and the fastening screw 40 passes through the through hole 31 and is screwed and fixed in the threaded hole 11 of the tuning screw 10, so that the resonant disk 20 and the tuning screw 10 can be easily and stably combined through the plastic fixing body 30 and the fastening screw 40, avoiding the problem of brittle cracking of the resonant disk 20. Moreover, since the tuning screw 10 in the present invention uses a metal material with a low thermal expansion coefficient, it can basically avoid the passive change of the distance between the resonant disk 20 and the resonator 80 in the case of large changes in high and low temperatures, and will not affect the normal use of the cavity filter.
[0023] In some embodiments, the tuning screw 10 is made of brass, preferably brass of model C3771, so that the tuning screw 10 has a lower thermal expansion coefficient.
[0024] In some embodiments, the resonant disk 20 is made of ceramic.
[0025] In some embodiments, the plastic fixture 30 is made of a high temperature resistant material; preferably, the plastic fixture 30 is made of polyetherimide, so that the plastic fixture 30 can remain stable at high temperatures, ensuring the structural reliability of the tuning component 100 and the normal use of the cavity filter.
[0026] In some embodiments, a flange portion 32 is formed at the upper end of the plastic fixing body 30 , and the flange portion 32 is combined with the upper surface of the resonance disk 20 , thereby enhancing the combination stability of the plastic fixing body 30 and the resonance disk 20 , and further ensuring the structural reliability of the tuning component 100 .
[0027] In some embodiments, the fastening screw 40 is made of metal, and the part of the fastening screw 40 that matches the threaded hole 11 is coated with glue in the circumferential direction to prevent loosening; through this design, it can ensure that the fastening screw 40 is firmly screwed in the threaded hole 11 of the tuning screw 10, and can also avoid the occurrence of glue falling due to excessive glue coating (360-degree glue coating) in the circumferential direction of the fastening screw 40, especially when it falls into the cavity 70 of the cavity filter, it will affect the performance of the cavity filter. Specifically, the fastening screw 40 is made of stainless steel.
[0028] As a preferred embodiment, the portion where the fastening screw 40 matches the threaded hole 11 is subjected to anti-loosening glue coating treatment for approximately 180 degrees in the circumferential direction.
[0029] Please combine Figure 4 The present invention also discloses a cavity filter, including a cavity 70, a resonator 80 and a tuning assembly 100. The resonator 80 is fixed in the cavity 70. The tuning assembly 100 is as described in the above embodiment. The tuning screw 10 is adjustably arranged on the cover plate 71 of the cavity 70. The resonance disk 20 is located in the cavity 70 and corresponds to the resonator 80. By adjusting the tuning screw 10, the distance between the resonance disk 20 and the resonator 80 can be changed.
[0030] In some embodiments, the cavity filter further includes a tuning nut 90 disposed on the cover plate 71 of the cavity 70, the tuning screw 10 is threadedly matched with the tuning nut 90, and the tightening torque of the tuning nut 90 is greater than 15 kgf.cm. Through this design, when vibration occurs, the tuning screw 10 and the tuning nut 90 can be more firmly combined, effectively improving the reliability of the product.
[0031] The above disclosure is only a preferred embodiment of the present invention, which is to facilitate the understanding and implementation of the present invention by those skilled in the art. It certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention still fall within the scope covered by the present invention.
Claims
1. A tuning component for a cavity filter, characterized in that: It includes a tuning screw made of metal, a resonance disk, a plastic fixed body and a fastening screw. A hollow portion is formed in the middle of the resonance disk, the plastic fixed body is injection molded in the hollow portion, a through hole is formed in the middle of the plastic fixed body, the bottom of the tuning screw is arranged on the plastic fixed body, the tuning screw is formed with a threaded hole corresponding to the through hole of the plastic fixed body, and the fastening screw passes through the through hole and is screwed and fixed in the threaded hole of the tuning screw.
2. The tuning component for a cavity filter according to claim 1, characterized in that: The tuning screw is made of brass.
3. The tuning component for a cavity filter according to claim 2, characterized in that: The resonant disk is made of ceramic material.
4. The tuning component for a cavity filter according to claim 1, characterized in that: The plastic fixing body is made of high temperature resistant material.
5. The tuning component for a cavity filter according to claim 4, characterized in that: The material of the plastic fixing body is polyetherimide.
6. The tuning component for a cavity filter according to claim 5, characterized in that: A flange portion is formed at the upper end of the plastic fixing body, and the flange portion is combined with the upper surface of the resonance disk.
7. The tuning component for a cavity filter according to claim 1, characterized in that: The fastening screw is made of metal, and the portion of the fastening screw that matches the threaded hole is coated with glue to prevent loosening in the circumferential direction.
8. The tuning component for a cavity filter according to claim 7, characterized in that: The part where the fastening screw cooperates with the threaded hole is subjected to anti-loosening glue coating treatment for approximately 180 degrees in the circumferential direction.
9. A cavity filter, characterized in that: It includes a cavity, a resonator and a tuning component, the resonator is fixed in the cavity, the tuning component is as described in any one of claims 1 to 8, the tuning screw is adjustably inserted through the cover plate of the cavity, the resonance disk is located in the cavity and corresponds to the resonator, and the distance between the resonance disk and the resonator can be changed by adjusting the tuning screw.
10. The cavity filter according to claim 9, characterized in that: It also includes a tuning nut arranged on the cover plate of the cavity, the tuning screw rod is threadedly matched with the tuning nut, and the tightening torque of the tuning nut is greater than 15kgf.cm.