WO2015074616A1

WO2015074616A1 - Filter

Info

Publication number: WO2015074616A1
Application number: PCT/CN2014/092007
Authority: WO
Inventors: 吴德强; 袁进华; 李金艳
Original assignee: 华为技术有限公司
Priority date: 2013-11-25
Filing date: 2014-11-24
Publication date: 2015-05-28
Also published as: CN203746999U

Abstract

The embodiments of the present invention disclose a filter. The filter of the present invention comprises: a cover panel and a cavity, said cavity opening upward, said cover panel fixedly covering the opening of said cavity, a self-locking tuning screw being fixed beneath said cover panel by means of a self-locking fixture, said self-locking tuning screw rotating to move up and down to adjust frequency, said cavity being a cavity formed via a die-casting process or a cavity formed via a machining process, a resonating bar being soldered by means of solder or bonded by means of conductive adhesive bonding to the bottom of the cavity, enabling said resonating bar to make continuous contact with said cavity. The embodiments of the present invention simplify the process, achieving a reliable and continuous connection between the resonating bar and the cavity, increasing the power capacity and tuning range of the filter, optimizing the communication indices of cavity filters.

Description

filter

The present application claims priority to Chinese Patent Application No. 20132075640, filed on Nov. 25, 2013, which is hereby incorporated by reference.

Technical field

Embodiments of the present invention relate to communication technologies, and in particular, to a filter.

Background technique

In the increasingly competitive market, the demand for miniaturization and light weight of filters is becoming more and more intense. Among them, in order to reduce the volume of the filter, an effective way is to make the cavity depth of the filter small.

1 is a schematic structural view of a prior art filter. As shown in FIG. 1, the filter adopts a single cavity structure, and the cavity depth is small. The tuning screw 11 is fixed on the cover 12 by a nut 15, and the resonant rod 13 is mounted. The piece is placed in the die-casting mold of the cavity 14, and then cast into a high-temperature metal liquid. As the high-temperature metal liquid cools and solidifies, the resonance rod 13 is combined with the cavity 14 to realize the fixing of the resonance rod 13. The filter structure shown in FIG. 1 can increase the range in which the tuning screw 11 moves up and down on the basis of the small cavity depth of the filter, thereby improving the tuning margin of the filter and avoiding the occurrence of sparking. However, the resonant rod 13 of such a filter can only achieve a fixed connection with the cavity 14 by a die-casting process, limiting the extent to which the filter cavity is deep, and the resonant rod 13 is inserted into the cavity 14 as an insert. In the mold, the process is complex, affecting the communication indicators of the cavity filter.

Summary of the invention

The embodiment of the invention provides a filter, which can simplify the process, realize reliable and continuous connection of the resonant rod and the cavity, increase the power capacity and tuning margin of the filter, and optimize the communication index of the cavity filter.

In a first aspect, an embodiment of the present invention provides a filter, including: a cover plate and a cavity, the cavity is open upward, the cover plate is fixedly closed on the opening of the cavity, and a self-locking tuning screw Fixed under the cover plate by a self-locking fixing device, the self-locking tuning screw is rotated up and down to realize adjustment The effect of the pitch frequency is that the cavity is a cavity formed by a die-casting process or a cavity formed by a machining process, and a resonant rod is bonded to the bottom of the cavity by soldering or conductive adhesive to achieve the The resonant rod is in continuous contact with the cavity.

In conjunction with the first aspect, in a first possible implementation manner of the first aspect, the self-locking fixing device is a stud riveted to a lower surface of the cover plate, the stud is a hollow structure, the screw The inner side wall of the column has an internal thread; the outer side wall of the self-locking tuning screw has an external thread, and the self-locking tuning screw is fixed to the cover by the cooperation of the external thread and the internal thread of the stud Bottom, the self-locking tuning screw achieves the effect of adjusting the frequency by rotating up and down along the thread; the self-locking tuning screw extends down into the interior of the resonant rod to reach the combination of the resonant rod and the bottom of the cavity At the point to increase the upper and lower adjustment range of the self-locking tuning screw.

In conjunction with the first aspect or the first possible implementation of the first aspect, in a second possible implementation of the first aspect, the top end of the side wall of the resonant rod is an outward flanged structure.

In conjunction with the first aspect, the first possible implementation of the first aspect to the second aspect, in a third possible implementation manner of the first aspect, the bottom of the cavity is provided with a boss. The resonant rod is bonded in the land area by soldering or conductive adhesive.

In conjunction with the third possible implementation of the first aspect, in a fourth possible implementation of the first aspect, the bottom of the cavity is provided with a machined boss, the side of the resonant rod The wall has a straight cylindrical structure, and the bottom of the resonant rod is a circular platform, and the circular platform is bonded in the region of the boss by soldering or conductive adhesive.

In conjunction with the third possible implementation of the first aspect, in a fifth possible implementation manner of the first aspect, the bottom of the cavity is provided with a machined boss, the side of the resonant rod The wall has a straight cylindrical structure, the bottom of the resonant rod is an annular hollow platform in the middle, the boss is snapped into the hollow portion of the circular platform to fix the position of the resonant rod, The annular platform is bonded to the surrounding area of the boss by soldering or conductive bonding.

In conjunction with the fifth possible implementation of the first aspect, in a sixth possible implementation manner of the first aspect, the boss is provided with an annular groove, the inner diameter of the annular groove is smaller than the circular platform The inner diameter of the annular groove is larger than the outer diameter of the annular platform, and the annular platform is bonded in the annular groove by soldering or conductive adhesive.

In conjunction with the third possible implementation of the first aspect, the seventh possible implementation in the first aspect In the present embodiment, the bottom of the cavity is provided with a machined two-stage boss, and the first stage boss of the two-stage boss is located above the second stage boss of the two-stage boss And the area of the first-stage boss is smaller than the area of the second-stage boss, the side wall of the resonant rod is a straight-tube structure, and the bottom of the resonant rod is an annular platform with a hollow in the middle. The first stage boss is snapped into the hollow portion of the circular platform to fix the position of the resonant rod, and the circular platform is bonded to the second level by soldering or conductive adhesive Within the Taiwan area.

In conjunction with the seventh possible implementation of the first aspect, in an eighth possible implementation manner of the first aspect, a high-weld boss is disposed on a sidewall of the first-stage boss, the first a stage boss is snapped into the hollow portion of the annular platform to fix the position of the resonant rod, the annular platform being stuck on the high weld boss to make the ring A gap for filling the solder or the conductive paste is left between the lower surface of the platform and the surface of the second stage boss, and the circular platform is bonded to the second level by soldering or conductive adhesive Within the Taiwan area.

In conjunction with the third possible implementation of the first aspect, in a ninth possible implementation manner of the first aspect, the bottom of the cavity is provided with a machined two-stage boss, the two stages a first stage boss of the boss is located above the second stage boss of the two stage boss, and an area of the first stage boss is smaller than an area of the second stage boss, the resonant rod The sidewall is subjected to an intermediate bending forming process to form a two-stage straight tubular structure, the inner diameter of the upper straight cylinder of the two-stage straight tubular structure is larger than the inner diameter of the lower straight cylinder of the two-stage straight tubular structure, and the resonant rod is opened downward. The first stage boss is engaged in the lower straight tube of the two-stage straight type structure, and the bottom of the lower straight tube of the two-stage straight type structure is bonded to the second stage boss area by soldering or conductive adhesive .

In conjunction with the first aspect, the first implementation of the first aspect to the second aspect, in a tenth possible implementation manner of the first aspect, the bottom of the cavity is provided with an annular groove. The resonant rod is bonded in the annular groove by soldering or conductive adhesive.

In conjunction with the tenth possible implementation of the first aspect, in an eleventh possible implementation manner of the first aspect, the bottom of the cavity is provided with an annular groove, and the side wall of the resonant rod is a straight tubular structure. The bottom of the resonant rod is an annular hollow platform in the middle, the inner diameter of the annular groove is smaller than the inner diameter of the circular platform, and the outer diameter of the annular groove is larger than the outer diameter of the circular platform. The annular platform is bonded in the annular groove by soldering or conductive adhesive.

In conjunction with the eleventh possible implementation of the first aspect, the twelfth possibility in the first aspect In an implementation manner, a high-weld boss is disposed on an outer sidewall of the annular groove, and the circular platform is stuck on the high-weld boss to make a lower surface of the circular platform A gap for filling the solder or the conductive paste is left between the bottom of the annular groove, and the annular platform is bonded in the annular groove by soldering or conductive adhesive.

With reference to the first aspect, the first to the twelfth possible implementation manner of the first aspect, in the thirteenth possible implementation manner of the first aspect, the wall thickness of the resonant rod is greater than or equal to 0.3 mm.

The filter of the embodiment of the invention improves the connection mode of the resonant rod and the cavity, and the bottom of the resonant rod is bonded to the bottom of the cavity by soldering or conductive adhesive, without installing screws, and does not occupy the vertical direction of the filter. The space increases the power capacity and tuning margin of the filter, saves time and time, realizes reliable and continuous connection of the resonant rod and the cavity, and greatly optimizes the communication index of the cavity filter.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description of the drawings used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any inventive labor.

1 is a schematic structural view of a prior art filter;

2 is a schematic structural view of a first embodiment of a filter according to the present invention;

3 is a schematic structural diagram of a second embodiment of a filter according to the present invention;

4A is a schematic structural view of a third embodiment of a filter according to the present invention;

4B is a schematic view of the bottom of the cavity of the third embodiment of the filter according to the present invention;

FIG. 5A is a schematic structural diagram of Embodiment 4 of a filter according to the present invention; FIG.

5B is a schematic bottom view of a cavity of a fourth embodiment of the filter according to the present invention;

6A is a schematic structural diagram of Embodiment 5 of a filter according to the present invention;

6B is a schematic bottom view of a cavity of a fifth embodiment of the filter according to the present invention;

7A is a schematic structural diagram of Embodiment 6 of a filter according to the present invention;

7B is a schematic bottom view of a cavity of a sixth embodiment of the filter according to the present invention;

8A is a schematic structural diagram of Embodiment 7 of a filter according to the present invention;

8B is a schematic bottom view of a cavity of a seventh embodiment of the filter according to the present invention;

9A is a schematic structural diagram of Embodiment 8 of a filter according to the present invention;

9B is a schematic bottom view of a cavity of the eighth embodiment of the filter of the present invention;

FIG. 10A is a schematic structural diagram of Embodiment 9 of a filter according to the present invention; FIG.

10B is a schematic bottom view of a cavity of a filter embodiment 9 of the present invention;

10C is a schematic view showing the bottom of the cavity of Embodiment 9 of the filter of the present invention;

11A is a schematic structural diagram of Embodiment 10 of a filter according to the present invention;

11B is a schematic view of the bottom of the cavity of the tenth embodiment of the filter of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

2 is a schematic structural view of a first embodiment of a filter according to the present invention. As shown in FIG. 2, the filter of the embodiment may adopt a cavity structure, including: a cover 22, a cavity 24, a self-locking tuning screw 21, and a self-locking Fixing device 25 and resonant rod 23. The cavity 24 is open upward, the cover 22 is fixedly closed on the opening of the cavity 24, and the self-locking tuning screw 21 is fixed under the cover 22 by the self-locking fixing device 25, and the self-locking tuning screw 21 is rotated up and down to realize adjustment. The function of the frequency is that the cavity 24 is a cavity formed by a die-casting process or a cavity formed by a machining process, and the resonant rod 23 is bonded to the bottom of the cavity 24 by soldering or conductive adhesive to realize the resonant rod 23 and the cavity. Continuous contact of body 24.

The filter of the present embodiment improves the connection manner of the resonant rod 23 and the cavity 24 compared with the prior art filter shown in FIG. 1. In this embodiment, the resonant rod 23 is a metal independent of the cavity 24. The resonant rod is bonded to the bottom of the cavity 24 by soldering or conductive adhesive. Such a connection realizes reliable and continuous connection of the resonant rod 23 and the cavity 24, so that the intermodulation performance of the filter is greatly improved, and the resonant rod 23 is independent of the cavity 24, and is connected by solder or conductive glue, and the filter cavity can be made deeper due to the simple process. The mold of the cavity 24 can be formed by a machining process in addition to the die casting process, and the cavity 24 does not need to be considered to be embedded in the resonant rod 23, so that it is not necessary to specialize. The door is reserved for the resonant rod 23, which simplifies the process and is convenient and quick to process, and greatly optimizes the communication index of the cavity filter.

Preferably, the resonant rod 23 can be made of a metal material having a wall thickness of 0.3 mm or more.

Preferably, the solder or conductive paste filled between the resonant rod 23 and the cavity 24 has a melting point of less than 260 degrees Celsius.

3 is a schematic structural view of a filter embodiment 2 of the present invention. As shown in FIG. 3, the filter of the embodiment is based on the filter structure shown in FIG. 2. Further, the self-locking fixture 25 may be riveted to The stud 251 of the lower surface of the cover plate 22 has a hollow structure, the inner side wall of the stud 251 has an internal thread (not shown), and the outer side wall of the self-locking tuning screw 21 has an external thread (Fig. The self-locking tuning screw 21 is fixed under the cover plate 22 by the cooperation of the external thread and the internal thread of the stud 251, and the self-locking tuning screw 21 is rotated up and down along the thread to realize the function of adjusting the frequency; The lock tuning screw 21 extends down into the interior of the resonant rod 23 to the junction of the resonant rod 23 and the bottom of the cavity 24 to increase the up and down adjustment range of the self-locking tuning screw 21.

In the filter of the embodiment, the self-locking tuning screw 21 is movably connected with the stud 251 riveted to the lower surface of the cover plate 22 in a threaded manner, and the self-locking tuning screw 21 can be screwed up or down along the thread. Wherein, the upper and lower adjustment range of the self-locking tuning screw 21 may be upward at the upper end thereof to reach the cover plate 22, and the downward end may be a lower end of the resonance rod 23 reaching the junction of the resonance rod 23 and the bottom of the cavity 24, so that In the case where the filter cavity depth is small, the range of up and down movement of the self-locking tuning screw 21 can be increased as much as possible, thereby achieving the purpose of increasing the adjustment margin and power capacity of the filter.

As shown in FIG. 3, the top end of the side wall of the resonant rod 23 may be an outward flanged structure, because the frequency of the filter cavity is increased as the depth of the filter cavity is reduced, in order to reduce the frequency to the required frequency band, usually The resonant rod 23 is an independent metal resonant rod in the embodiment. The resonant structure of the resonant rod 23 solves the limitation of the structural design of the resonant rod and reduces the frequency of the filter. The filter reduces the depth of the cavity to achieve miniaturization of the filter. Alternatively, the top end of the side wall of the resonant rod 23 may not be turned outward.

Further, as an alternative, in the filter structure shown in FIG. 2, a boss may be disposed at the bottom of the cavity 24, and the resonant rod 23 is bonded to the land area by soldering or conductive adhesive. The boss can be machined due to its small area, and the surface is smooth and flat, which is convenient for solder. Welding or conductive adhesive bonding.

In the following, several specific embodiments are used to describe in detail the connection mode of the resonant rod and the cavity in the structure with the boss at the bottom of the cavity.

4A is a schematic structural view of a third embodiment of a filter according to the present invention, and FIG. 4B is a schematic diagram of a bottom portion of a cavity according to a third embodiment of the filter of the present invention. FIG. 4A and FIG. 4B are combined. The filter of the embodiment may include: a cover plate. 32. The cavity 34, the self-locking tuning screw 31, the stud 35 and the resonant rod 33. The cavity 34 is open upward, the cover 32 is fixedly closed on the opening of the cavity 34, the stud 35 is riveted to the lower surface of the cover 32, the stud 35 is a hollow structure, and the inner side wall of the stud 35 is internally threaded. The outer side wall of the self-locking tuning screw 31 has an external thread. The self-locking tuning screw 31 is fixed to the lower side of the cover plate 32 by the cooperation of the external thread and the internal thread of the stud 35, and the self-locking tuning screw 31 is rotated up and down to realize the adjustment. The role of frequency. The cavity 34 is a cavity formed by a die-casting process or a cavity formed by a machining process, and a mechanically formed boss 341 is disposed at the bottom thereof, and the side wall of the resonant rod 33 has a straight cylindrical structure with a top end outward. The bottom of the resonant rod 33 is a circular platform 331 which is bonded to the region of the boss 341 by soldering or conductive adhesive.

In the filter of this embodiment, solder or conductive paste is filled between the bottom circular platform 331 of the resonant rod 33 and the boss 341 of the cavity 34, and the resonant rod 33 and the cavity 34 are fixed by soldering or bonding. Connected together, the self-locking tuning screw 31 goes down into the interior of the resonant rod 33 to the junction of the resonant rod 33 and the bottom of the cavity 34. The filter structure shown in FIG. 4 can increase the range of up-and-down movement of the self-locking tuning screw 31 to achieve the purpose of increasing the adjustment margin and power capacity of the filter; achieving continuous contact between the resonant rod 33 and the cavity 34, so as to filter The intermodulation performance of the device is improved; the mold structure of the cavity 34 is simplified. It is a filter structure that is very suitable for reducing the filter volume.

5A is a schematic structural view of a fourth embodiment of a filter according to the present invention, and FIG. 5B is a schematic diagram of a bottom portion of a cavity according to a fourth embodiment of the filter of the present invention. FIG. 5A and FIG. 5B are combined, and the filter of the embodiment may include: a cover plate. 42. A cavity 44, a self-locking tuning screw 41, a stud 45, and a resonant rod 43. The cavity 44 is open upward, the cover 42 is fixedly closed on the opening of the cavity 44, the stud 45 is riveted to the lower surface of the cover 42 , the stud 45 is hollow, and the inner side wall of the stud 45 is internally threaded. The outer side wall of the self-locking tuning screw 41 has an external thread. The self-locking tuning screw 41 is fixed to the lower side of the cover 42 by the cooperation of the external thread and the internal thread of the stud 45, and the self-locking tuning screw 41 is rotated up and down to realize the adjustment. The role of frequency. The cavity 44 is a cavity formed by a die casting process or a cavity formed by a machining process. The bottom of the resonance rod 43 is provided with a machined projection 441. The side wall of the resonance rod 43 has a straight cylindrical structure, the top end of which is turned outward, and the bottom of the resonance rod 43 is an annular platform 431 which is hollowed out in the middle, and the boss 441 The card is snapped into the hollow portion of the annular platform 431 to fix the position of the resonant rod 43, and the circular platform 431 is bonded to the surrounding area of the boss 441 by soldering or conductive adhesive.

In the filter of this embodiment, the boss 441 passes through the hollow portion of the circular platform 431 and is engaged in the hollow portion of the circular platform 431 to fix the position of the resonant rod 43 at the bottom of the resonant rod 43. The soldering or conductive paste is filled between the shaped platform 431 and the surrounding area of the boss 441 of the cavity 44, and the resonant rod 43 is fixedly coupled to the cavity 44 by soldering or bonding, and the self-locking tuning screw 41 is downwardly connected. Inside the resonant rod 43 is reached to the junction of the resonant rod 43 and the bottom of the cavity 44. The filter structure of the embodiment can increase the range of the up-and-down movement of the self-locking tuning screw 41 to achieve the purpose of increasing the adjustment margin and power capacity of the filter; achieving continuous contact between the resonant rod 43 and the cavity 44, so that the filter The intermodulation performance is improved; the boss 441 is engaged with the circular platform 431 to fix the position of the resonant rod 43; the mold structure of the cavity 44 is simplified. It is a filter structure that is very suitable for reducing the filter volume.

6A is a schematic structural view of a fifth embodiment of a filter according to the present invention, and FIG. 6B is a schematic diagram of a bottom portion of a cavity according to a fifth embodiment of the filter of the present invention. FIG. 6A and FIG. 6B are combined, and the filter of the embodiment is shown in FIG. 5A and FIG. Further, on the basis of the filter structure shown in FIG. 5B, an annular groove 442 is formed on the boss 441. The inner diameter of the annular groove 442 is smaller than the inner diameter of the circular ring platform 431, and the outer diameter of the annular groove 442 is larger than the circular ring platform 431. The outer diameter of the annular platform 431 is bonded to the annular groove 442 by soldering or conductive adhesive.

In the filter of this embodiment, an annular groove 442 is disposed on the boss at the bottom of the cavity 44. The inner diameter, the outer diameter and the position of the annular groove 442 can accommodate the circular platform 431 of the lower resonance rod 43. The shaped platform 431 is bonded to the annular groove 442 by soldering or conductive adhesive, and the fixed resonant rod 43 and the cavity 44 are well fixed to be in continuous contact. It is a filter structure that is very suitable for reducing the filter volume.

7A is a schematic structural view of a sixth embodiment of a filter according to the present invention, and FIG. 7B is a schematic diagram of a bottom portion of a cavity of the sixth embodiment of the filter according to the present invention. FIG. 7A and FIG. 7B are combined, and the filter of the embodiment may include: a cover. 52. The cavity 54, the self-locking tuning screw 51, the stud 55 and the resonant rod 53. The cavity 54 is open upward, the cover 52 is fixedly closed on the opening of the cavity 54, the stud 55 is riveted to the lower surface of the cover 52, the stud 55 is hollow, and the inner side wall of the stud 55 is internally threaded. Self-locking tuning The outer side wall of the screw 51 has an external thread. The self-locking tuning screw 51 is fixed to the lower side of the cover 52 by the cooperation of the external thread and the internal thread of the stud 55, and the self-locking tuning screw 51 is rotated up and down to realize the frequency adjustment function. The cavity 54 is a cavity formed by a die-casting process or a cavity formed by a machining process, and a mechanically processed two-stage boss is disposed at the bottom thereof, and the first-stage boss 541a of the two-stage boss is located at two stages. Above the second stage boss 541b of the boss, the area of the first stage boss 541a is smaller than the area of the second stage boss 541b, and the side wall of the resonant rod 53 is a straight cylindrical structure, the top end of which is turned outward, and the resonance The bottom of the rod 53 is an intermediate hollow circular platform 531. The first stage boss 541a is snapped into the hollow portion of the circular platform 531 to fix the position of the resonant rod 53, and the circular platform 531 is soldered or The conductive paste is bonded in the region of the second stage boss 541b.

In the filter of this embodiment, the first stage boss 541a passes through the hollow portion of the circular platform 531, and is engaged in the hollow portion of the circular platform 531 to fix the position of the resonant rod 53 at the resonant rod 53. The bottom annular platform 531 and the second stage boss 541b of the cavity 54 are filled with solder or conductive paste, and the resonant rod 53 and the cavity 54 are fixedly connected by welding or bonding, and the self-locking tuning screw is fixed. 51 goes deeper into the inside of the resonance rod 53 to reach the junction of the resonance rod 53 and the bottom of the cavity 54. The filter structure of the embodiment can increase the range of up and down movement of the self-locking tuning screw 51, thereby increasing the adjustment margin and power capacity of the filter; achieving continuous contact between the resonant rod 53 and the cavity 54, and making the filter The intermodulation performance is improved; the first stage boss 541a is engaged with the circular platform 531 to fix the position of the resonant rod 53; the mold structure of the cavity 54 is simplified. It is a filter structure that is very suitable for reducing the filter volume.

8A is a schematic structural view of a seventh embodiment of a filter according to the present invention, and FIG. 8B is a schematic diagram of a bottom portion of a cavity of a seventh embodiment of the filter according to the present invention. FIG. 8A and FIG. 8B are combined, and the filter of the embodiment is shown in FIG. 7A and FIG. Further, based on the filter structure shown in FIG. 7B, further, a high-weld boss 542 is disposed on the sidewall of the first-stage boss 541a, and the first-stage boss 541a is engaged with the hollow portion of the circular platform 531. Inside, to fix the position of the resonant rod 53, the annular platform 531 is stuck on the high-weld boss 542 so that there is a gap between the lower surface of the circular platform 531 and the surface of the second stage boss 541b. The annular platform 531 is bonded to the region of the second stage boss 541b by soldering or conductive adhesive to fill the gap of the solder or the conductive paste.

In the filter of this embodiment, a high-weld boss 542 is disposed on the sidewall of the first stage boss 541a, and the circular platform 531 is stuck on the high-weld boss 542 to raise the circular platform 531. Position so that A gap for filling the solder or the conductive paste is left between the lower surface of the annular platform 531 and the surface of the second stage boss 541b, by which sufficient solder or conductive paste can be filled. The filter structure of this embodiment is the same as the structure shown in Figs. 7A and 7B, and is a filter structure which is very suitable for reducing the filter volume.

Further, as an alternative, in the filter structure shown in FIG. 2, an annular groove may be disposed at the bottom of the cavity 24, and the resonant rod 23 is bonded to the annular groove by soldering or conductive adhesive. The annular groove can be formed by machining, and the surface is smooth and flat, which is convenient for soldering or conductive adhesive bonding.

In the following, several specific embodiments are used to describe in detail the connection mode of the resonant rod and the cavity in the structure with the annular groove at the bottom of the cavity.

9A is a schematic structural view of a filter embodiment 8 of the present invention, and FIG. 9B is a schematic diagram of a bottom portion of a cavity according to Embodiment 8 of the filter of the present invention. FIG. 9A and FIG. 9B are combined, and the filter of the embodiment may include: a cover plate. 62. The cavity 64, the self-locking tuning screw 61, the stud 65 and the resonant rod 63. The cavity 64 is open upward, the cover 62 is fixedly closed on the opening of the cavity 64, the stud 65 is riveted to the lower surface of the cover plate 62, the stud 65 is hollow, and the inner side wall of the stud 65 is internally threaded. The outer side wall of the self-locking tuning screw 61 has an external thread. The self-locking tuning screw 61 is fixed to the lower side of the cover plate 62 by the cooperation of the external thread and the internal thread of the stud 65, and the self-locking tuning screw 61 is rotated up and down to realize the adjustment. The role of frequency. The cavity 64 is a cavity formed by a die-casting process or a cavity formed by a machining process, and an annular groove 641 is disposed at a bottom thereof, and a side wall of the resonant rod 63 has a straight cylindrical structure, and a top end thereof is turned outward, and the resonance rod 63 The bottom of the bottom is an annular hollow platform 631 having an inner diameter smaller than the inner diameter of the annular platform 631, the outer diameter of the annular groove 641 is larger than the outer diameter of the circular platform 631, and the annular platform 631 is soldered. Or a conductive paste is bonded in the annular groove 641.

In the filter of this embodiment, an annular groove 641 is disposed on the boss at the bottom of the cavity 64. The inner diameter, the outer diameter and the position of the annular groove 641 can accommodate the circular platform 631 of the lower resonant rod 63. The shaped platform 631 is bonded in the annular groove 641 by soldering or conductive adhesive, and the fixed resonant rod 63 and the cavity 64 are well fixed to be in continuous contact. It is a filter structure that is very suitable for reducing the filter volume.

10A is a schematic structural view of a filter body according to Embodiment 9 of the present invention, FIG. 10B is a schematic diagram of a bottom portion of a cavity of Embodiment 9 of the filter of the present invention, and FIG. 10C is a bottom view of a cavity of Embodiment 9 of the filter of the present invention. FIG. 10A, FIG. 10B and FIG. 10C are combined. The filter of the present embodiment is further provided on the outer side wall of the annular groove 641 on the basis of the filter structure shown in FIGS. 9A and 9B. A high-weld boss 642 is attached to the high-weld boss 642 such that a gap between the lower surface of the annular platform 631 and the bottom of the annular groove 641 is filled with solder or conductive paste. The slit, annular platform 631 is bonded in the annular groove 641 by soldering or conductive adhesive.

The filter of this embodiment is provided with a high-weld boss 642 on the outer side wall of the annular groove 641. The circular ring platform 631 is stuck on the high-weld boss 642 to raise the position of the circular platform 631. A gap for filling the solder or the conductive paste is left between the lower surface of the annular platform 631 and the bottom surface of the annular groove 641, and the gap can be filled with sufficient solder or conductive paste. The filter structure of this embodiment is the same as the structure shown in Figs. 9A and 9B, and is a filter structure which is very suitable for reducing the filter volume.

11A is a schematic structural view of a tenth embodiment of a filter according to the present invention, and FIG. 11B is a schematic diagram of a bottom portion of a cavity according to a tenth embodiment of the filter according to the present invention. FIG. 11A and FIG. 11B are combined, and the filter of the embodiment may include: a cover plate. 72. A cavity 74, a self-locking tuning screw 71, a stud 75, and a resonant rod 73. The cavity 74 is open upward, the cover plate 72 is fixedly closed on the opening of the cavity 74, the stud 75 is riveted to the lower surface of the cover plate 72, the stud 75 is hollow, and the inner side wall of the stud 75 is internally threaded. The outer side wall of the self-locking tuning screw 71 has an external thread. The self-locking tuning screw 71 is fixed to the lower side of the cover plate 72 by the cooperation of the external thread and the internal thread of the stud 75, and the self-locking tuning screw 71 is rotated up and down to realize the adjustment. The role of frequency. The cavity 74 is a cavity formed by a die-casting process or a cavity formed by a machining process, and a mechanically processed two-stage boss is arranged at the bottom thereof, and the first-stage boss 741a of the two-stage boss is located at two stages. Above the second stage boss 741b of the boss, the area of the first stage boss 741a is smaller than the area of the second stage boss 741b, and the side wall of the resonance rod 73 is subjected to intermediate bending forming processing to form a two-stage straight type structure. The inner diameter of the upper straight tube 732a of the two-stage straight type structure is larger than the inner diameter of the lower straight tube 732b of the two-stage straight type structure, the top end of the upper straight tube 732a is outwardly turned, the resonance rod 73 is opened downward, and the first stage boss 741a is coupled to the two sides. In the lower straight cylinder 732b of the straight cylindrical structure, the bottom of the lower straight cylinder 732b of the two-stage straight type structure is bonded to the second stage boss 741b by soldering or conductive adhesive.

In the filter of this embodiment, the resonance rod 73 is subjected to a bending forming process to form a structure in which the inner diameter of the upper straight cylinder 732a is larger than the inner diameter of the lower straight cylinder 732b of the two-stage straight type structure, and the lower portion of the resonance rod 73 The ends are all hollowed out, without the bottom, the first stage boss 741a is snapped into the lower straight tube 732b of the two-stage straight type structure, and the bottom of the lower straight tube 732b of the two-stage straight type structure is bonded to the second stage by soldering or conductive adhesive. Within the 741b area. The filter structure of the embodiment is the most reliable structure, and the range of up and down movement of the self-locking tuning screw 51 can be increased to achieve the purpose of increasing the adjustment margin and power capacity of the filter; and the resonant rod 53 and the cavity 54 are realized. The continuous contact improves the intermodulation performance of the filter; the mold structure of the cavity 54 is simplified. It is a filter structure that is very suitable for reducing the filter volume.

It should be noted that the bosses or the annular grooves at the bottom of the filter cavity shown in FIG. 4A to FIG. 11B may be other shapes, which are not specifically limited in the embodiment of the present invention.

One of ordinary skill in the art will appreciate that all or part of the steps to implement the various method embodiments described above may be accomplished by hardware associated with the program instructions. The aforementioned program can be stored in a computer readable storage medium. The program, when executed, performs the steps including the foregoing method embodiments; and the foregoing storage medium includes various media that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A filter comprising: a cover plate and a cavity, the cavity is open upward, the cover plate is fixedly attached to the opening of the cavity, and a self-locking tuning screw is fixed by the self-locking fixing device Below the cover plate, the self-locking tuning screw is rotated up and down to realize the effect of adjusting the frequency, wherein the cavity is a cavity formed by a die-casting process or a cavity formed by a machining process, and a resonant rod Bonding to the bottom of the cavity by soldering or conductive bonding to achieve continuous contact of the resonant rod with the cavity.
The filter according to claim 1, wherein the self-locking fixing device is a stud riveted to a lower surface of the cover plate, the stud is a hollow structure, and the inner side wall of the stud is Having an internal thread; the outer side wall of the self-locking tuning screw has an external thread, and the self-locking tuning screw is fixed under the cover plate by the cooperation of the external thread and the internal thread of the stud, The self-locking tuning screw achieves the effect of adjusting the frequency by rotating up and down along the thread; the self-locking tuning screw extends down into the interior of the resonant rod to reach the junction of the resonant rod and the bottom of the cavity to increase The up and down adjustment range of the self-locking tuning screw.
The filter according to claim 1, wherein a top end of the side wall of the resonant rod is an outward flanged structure.
The filter according to claim 2, characterized in that the top end of the side wall of the resonant rod is an outward flanged structure.
The filter according to any one of claims 1 to 4, wherein a bottom of the cavity is provided with a boss, and the resonant rod is bonded to the land area by soldering or conductive adhesive. .
The filter according to claim 5, wherein the bottom of the cavity is provided with a machined boss, the side wall of the resonant rod has a straight cylindrical structure, and the bottom of the resonant rod is A circular platform that is bonded to the land area by soldering or conductive bonding.
The filter according to claim 5, wherein the bottom of the cavity is provided with a machined boss, the side wall of the resonant rod has a straight cylindrical structure, and the bottom of the resonant rod is An annular hollow platform in the middle, the boss is snapped into the hollow portion of the circular platform to fix the position of the resonant rod, and the circular platform is bonded by soldering or conductive adhesive Within the surrounding area of the boss.
The filter according to claim 7, wherein said boss is provided with a ring a groove having an inner diameter smaller than an inner diameter of the annular platform, an outer diameter of the annular groove being larger than an outer diameter of the circular platform, the circular platform being bonded by soldering or conductive bonding In the annular groove.
The filter according to claim 5, wherein a bottom of the cavity is provided with a machined two-stage boss, and the first stage boss of the two-stage boss is located at the two stages. Above the second stage boss of the boss, and the area of the first stage boss is smaller than the area of the second stage boss, the side wall of the resonant rod is a straight type structure, and the bottom of the resonant rod In the middle of the hollow circular platform, the first stage boss is snapped into the hollow portion of the circular platform to fix the position of the resonant rod, the circular platform is soldered or electrically conductive The glue is bonded in the second stage land area.
The filter according to claim 9, wherein a sidewall of the first stage boss is provided with a high-weld boss, and the first-stage boss is engaged with the circular platform. a position in the hollow portion to fix the resonant rod, the annular platform being stuck on the high-weld boss to make the lower surface of the circular platform and the second-stage boss A gap is left between the surfaces for filling the solder or conductive paste, and the annular platform is bonded to the second stage land area by soldering or conductive adhesive.
The filter according to claim 5, wherein a bottom of the cavity is provided with a machined two-stage boss, and the first stage boss of the two-stage boss is located at the two stages. Above the second stage boss of the boss, and the area of the first stage boss is smaller than the area of the second stage boss, and the side wall of the resonant rod is subjected to intermediate bending forming to form a two-stage straight type The inner diameter of the upper straight cylinder of the two-stage straight type structure is larger than the inner diameter of the lower straight cylinder of the two-stage straight type structure, the resonant rod is opened downward, and the first stage boss is engaged with the two-stage straight tube In the lower straight cylinder of the type structure, the bottom of the lower straight cylinder of the two-stage straight type structure is bonded in the second stage boss area by soldering or conductive adhesive.
The filter according to any one of claims 1 to 4, characterized in that the bottom of the cavity is provided with an annular groove, and the resonant rod is bonded in the annular groove by soldering or conductive adhesive.
The filter according to claim 12, wherein the bottom of the cavity is provided with an annular groove, the side wall of the resonant rod is a straight cylindrical structure, and the bottom of the resonant rod is hollowed in the middle. An annular platform having an inner diameter smaller than an inner diameter of the annular platform, the outer diameter of the annular groove being larger than an outer diameter of the annular platform, the annular platform being soldered or A conductive paste is bonded in the annular groove.
The filter according to claim 13, wherein a high-weld boss is disposed on an outer side wall of said annular groove, said annular platform being stuck on said high-weld boss to A gap for filling the solder or the conductive paste is left between the lower surface of the annular platform and the bottom of the annular groove, and the circular platform is bonded in the annular groove by soldering or conductive adhesive .
The filter according to any one of claims 1 to 3, 5 to 11, 13, or 14, wherein the resonance rod has a wall thickness of 0.3 mm or more.
The filter according to claim 4, wherein said resonant rod has a wall thickness of 0.3 mm or more.
The filter according to claim 12, wherein said resonant rod has a wall thickness of 0.3 mm or more.