Filter for communication device

Abstract

The present invention relates to a filter for a communication device. The filter for a communication device comprises: a filter body having one or more cavities formed therein; at least one resonator, the front end of which is positioned to extend by a predetermined length from the bottom surface of one side of the filter body, corresponding to the bottom surface of a cavity, toward the other side; and tunable bars which are coupled to tuning holes formed in the filter body to communicate with the respective cavities, and which are capable of adjusting the frequency by changing the shape of a portion corresponding to a range in the thickness direction of the tuning hole. Thus, the present invention provides the advantages of frequency tuning and modification being easy without using a tuning screw method or applying an additional structure, and of enabling reduction in product manufacturing costs.

Description

Filters for communication devices

[0001] The present invention relates to a filter for communication devices, and more specifically, to a filter for communication devices that facilitates automation of frequency tuning and reduces the production cost of products.

[0002] Tuning screws have been used for decades to vary the frequency characteristics of filters for communication devices, but the use of tuning screws presents difficulties in automated production. Accordingly, many studies and results on methods for varying (tuning) the frequency of filters without using tuning screws have been applied for and disclosed as patents.

[0003] More specifically, conventional filters for communication devices adopt a method of setting a target frequency of the filter for communication devices and adjusting the frequency downward, and specifically, the frequency is adjusted downward by increasing capacitance by reducing the distance (gap) between the resonator in the cavity and the filter tuning cover.

[0004] However, there are frequent cases where the frequency needs to be adjusted upward again for fine frequency adjustment after the filter tuning cover of the conductive material (metal) is deformed by a stamping method. In this case, it is very difficult to restore the deformed filter tuning cover and adjust the frequency upward.

[0005] To solve these problems, additional structures are sometimes used, but these additional structures lead to the problem of making it difficult to maintain the frequency characteristics of the filter the same in high or low temperature conditions, and thus there are no successful cases of actual commercialization.

[0006]

[0007] The present invention has been devised to solve the above-mentioned technical problem, and its purpose is to provide a filter for a communication device that is easy to design automatically for frequency tuning by applying a tunable bar whose shape can be easily changed for each of a plurality of cavities.

[0008] In addition, another object of the present invention is to provide a filter for a communication device that can significantly reduce the production cost of the product by omitting a configuration such as a nut for fixing a conventional tuning screw.

[0009] In addition, another object of the present invention is to provide a filter for a communication device with improved PIMD performance by preventing incomplete contact between a tuning hole and a tunable bar.

[0010] The tasks of the present invention are not limited to the tasks mentioned above, and other technical tasks not mentioned will be clearly understood by those skilled in the art from the description below.

[0011] A filter for a communication device according to one embodiment of the present invention comprises a filter body having at least one cavity formed therein, at least one resonator having a tip extending a predetermined length from one side of the bottom surface of the filter body corresponding to the bottom surface of the cavity to the other side, and a tunable bar coupled to each of a plurality of tuning holes formed in the filter body so as to be in communication with each of the cavities, and capable of adjusting a frequency by causing a shape deformation of an outer surface of a portion exposed into the cavity, the portion including a portion corresponding to a range in the thickness direction of the tuning hole.

[0012] Here, the tunable bar may include a joining flange that is hooked to the outer edge of the tuning hole in the filter tuning cover, a downward frequency adjustment unit that extends from the joining flange through the tuning hole into the cavity of the filter body and includes a downward tuning surface that is arranged parallel to a resonant disk panel provided in the resonator, and an upward frequency adjustment unit that is defined between the downward frequency adjustment unit and the joining flange.

[0013] In addition, the downward frequency adjustment unit and the upward frequency adjustment unit may be formed to have the same diameter, but may be spaced apart from the inner end of the tuning hole.

[0014] In addition, the downward frequency adjustment unit may be formed to have a smaller diameter than the upward frequency adjustment unit, but may be formed to have a step with respect to the upward frequency adjustment unit.

[0015] Additionally, the upward frequency adjustment unit may be formed so that its diameter gradually decreases as it goes toward the inside of the cavity.

[0016] Additionally, the tuning hole corresponding to the position of the upward frequency adjustment unit may include a tapered end formed so that the diameter gradually increases toward the cavity.

[0017] Additionally, a frequency measurement hole communicating with the cavity may be further formed at the center of the downward tuning surface.

[0018] In addition, frequency tuning correction through the upward frequency adjustment unit of the tunable bar can be performed by a rotating compression jig that is introduced into the interior of the upward frequency adjustment unit and then rotates to shape-deform the inner surface of the upward frequency adjustment unit outward.

[0019] In addition, frequency tuning correction through the upward frequency adjustment part of the tunable bar can be performed by an expansion compression jig that is introduced into the interior of the upward frequency adjustment part and then spreads outward toward two or more points of the upward frequency adjustment part, thereby deforming the inner surface of the frequency adjustment part outward.

[0020] In addition, frequency adjustment within the cavity can be achieved by deformation of the inner surface or the downward tuning surface of the downward frequency adjustment unit, and correction of the frequency adjusted by the downward frequency adjustment unit can be achieved by deformation of the inner surface of the upward frequency adjustment unit.

[0021] In addition, the tunable bar may include a joining flange that is forcefully fitted into the inner circumference of the tuning hole, and the joining flange may have a plurality of cut portions formed in a circumferential direction so that a predetermined tension force is continuously provided to the inner circumference of the tuning hole after being forcefully fitted into the tuning hole.

[0022] Additionally, the outer surface of the above-mentioned joint flange can be formed by knurling processing.

[0023] Additionally, in the area corresponding to the above-mentioned upward frequency adjustment section, at least two frequency adjustment protrusions may protrude to a predetermined depth toward the inner center.

[0024] In addition, in the area corresponding to the above-mentioned upward frequency adjustment section, a plurality of frequency adjustment slits that are formed long in the vertical direction and penetrate inside and outside can be formed spaced apart in the circumferential direction.

[0025] In addition, a gap portion connecting the upper end of the upward frequency adjustment unit and the joining flange may be further included, and the gap portion may be formed to protrude further outward from the tuning hole.

[0026] Additionally, the tuning hole may be formed in a filter tuning cover provided to cover the opened other side of the filter body.

[0027]

[0028] According to a filter for a communication device according to one embodiment of the present invention, an effect of easy automated design of frequency tuning can be achieved.

[0029] In addition, the present invention can achieve the effect of reducing the production cost of the product by omitting the nut for fixing the conventional tuning screw.

[0030] In addition, since the present invention has a structure in which there is no incomplete contact between the filter tuning cover and the tunable bar, it is possible to achieve an effect of improving PIMD performance that reduces filter performance.

[0031]

[0032] Figure 1 is a cross-sectional view showing a filter for a communication device according to one embodiment of the present invention.

[0033] Figures 2a to 2g are drawings showing the installation of a tunable bar according to the first to seventh implementation examples of the present invention.

[0034] Fig. 3 is a cross-sectional view showing downward adjustment (a) and upward adjustment (b) of frequency tuning using a tunable bar among the configurations of Fig. 1.

[0035] Fig. 4 is a cross-sectional view showing a modified example of the filter tuning cover in the configuration of Fig. 1.

[0036] Figure 5 is a cross-sectional view showing the upward adjustment of frequency tuning using various upward adjustment tools.

[0037]

[0038] <Explanation of symbols>

[0039] 1: Filter for communication device 10: Filter body

[0040] 20; Filter tuning cover 25: Tuning hole

[0041] 27: Taper stage 30: Resonator

[0042] 31: Resonant bar 32: Resonant disk panel

[0043] 100: Tunable bar 110,110': Joint flange

[0044] 111: Separation part 112: Cutting part

[0045] 115: Welding section 120: Frequency adjustment section

[0046] 120D: Downward frequency adjustment section 120U: Upward frequency adjustment section

[0047] 120B: Downward tuning surface 120h: Frequency measurement hole

[0048] 125P: Frequency adjustment protrusion 125s: Frequency adjustment slit

[0049]

[0050] Hereinafter, a filter for a communication device according to one embodiment of the present invention will be described in detail with reference to the attached drawings.

[0051] When assigning reference numerals to components in each drawing, it should be noted that identical components are assigned the same numerals whenever possible, even if they appear on different drawings. Furthermore, when describing embodiments of the present invention, if a detailed description of a related known configuration or function is deemed to hinder understanding of the embodiments of the present invention, the detailed description will be omitted.

[0052] When describing components of embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only intended to distinguish the components from other components, and do not limit the nature, order, or sequence of the components. Furthermore, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this application.

[0053]

[0054] Fig. 1 is a cross-sectional view showing a filter for a communication device according to one embodiment of the present invention.

[0055] A filter (1) for a communication device according to the present invention, as shown in FIG. 1, includes a filter body (10) having at least one cavity (C) formed therein, at least one resonator (30) having a tip extending a predetermined length from one side of the bottom surface of the filter body (10) corresponding to the bottom surface of the cavity (C) to the other side, and a tunable bar (100) coupled to a tuning hole (25) formed in the filter body (10) so as to be in communication with each of at least one of the cavities (C), and capable of adjusting a frequency by causing a shape deformation of an outer surface of a portion exposed into the cavity (C) including a portion corresponding to a range in the thickness direction of the tuning hole (25).

[0056] More specifically, although not shown in the drawing, a plurality of cavities (C) are provided inside the filter body (10) and are partitioned by unillustrated partition walls or windows, and a plurality of resonators (30) may be provided inside each cavity (C) to function by changing individual frequency characteristics.

[0057] The resonator (30) may include a resonance bar (31) whose tip is positioned so as to extend from the bottom surface (lower surface) of the cavity (C) of the filter body (10) to the side where the filter tuning cover (20) is positioned, and a resonance disk panel (32) provided at the tip of the resonance bar (31) and provided in the form of a metal panel wider than the diameter of the resonance bar (31).

[0058] Meanwhile, the other side facing the bottom surface (lower surface) of the cavity (C) of the filter body (10) may be formed to be open, and a filter tuning cover (20) may be provided to cover the opened other side of the filter body (10). However, the other side of the filter body (10) does not necessarily have to be formed to be open, and may be provided to be shielded depending on the manufacturing method of the filter body (10).

[0059] Here, when the filter tuning cover (20) is configured to cover the other side of the open side of the filter body (10), the tuning hole (25) may be formed in the filter tuning cover (20), and when the filter body (10) is formed so that the other side is shielded by itself, the tuning hole (25) may be formed to penetrate the shielded surface constituting the other side of the filter body (10). At this time, a plurality of the above-described tunable bars (100) may be installed in the tuning holes (25) formed at positions corresponding to each resonator (30) or individual cavity (C). Hereinafter, the description will be made on the assumption that the plurality of tuning holes (25) are formed in the filter tuning cover (20) provided to cover the other side of the open side of the filter body (10).

[0060] Here, a plurality of tuning holes (25) are installed as a portion where a plurality of tunable bars (100) are installed, and can be formed in the shape of circular holes that connect the exterior of the filter body (10) or the filter tuning cover (20) and the cavity (C).

[0061] The tunable bar (100) installed in the tuning hole (25) may have its outer circumference spaced apart from the inner circumference of the tuning hole (25) by a predetermined distance. More specifically, the tuning hole (25) is formed to correspond to the thickness of the filter body (10) or the filter tuning cover (20), and may be spaced apart from the inner circumference of the tuning hole (25) by a predetermined distance in a direction orthogonal to the thickness direction so as to form an inner capacitance between the outer circumference of the tunable bar (100) and the tuning hole (25) by a length corresponding to the thickness of the tuning hole (25).

[0062] FIGS. 2A to 2G are drawings showing the installation appearance of tunable bars according to the first to seventh implementation examples of the present invention. More specifically, each (a) of FIGS. 2A to 2G is a cross-sectional view showing the installation appearance of tunable bars (100A to 100G) according to each implementation example in a tuning hole (25) of a filter body (10) or a filter tuning cover (20), each (b) of FIGS. 2A to 2G is a front view of tunable bars (100A to 100G) according to each implementation example, and each (c) of FIGS. 2A to 2G is a bottom view of tunable bars (100A to 100G) according to each implementation example.

[0063] A filter (1) for a communication device according to one embodiment of the present invention may include a tunable bar (100) according to the first to fourth embodiments, which includes a joining flange (110) that is connected by being hooked to the outer edge of a tuning hole (25) of a filter body (10) or a filter tuning cover (20), as shown in FIGS. 2A to 2D.

[0064] In addition, the tunable bar (100A to 100D) according to the first to fourth implementation examples may further include a downward frequency adjustment unit (120D) that extends from the joint flange (110) through the tuning hole (25) into the cavity (C) of the filter body (10) and includes a downward tuning surface (120B) arranged parallel to the resonant disk panel (32) of the resonator (30), and an upward frequency adjustment unit (120U) defined between the downward frequency adjustment unit (120D) and the joint flange (110).

[0065] The joining flange (110) of the tunable bar (100A to 100D) according to the first to fourth embodiments is bent orthogonally in the outward direction from the upper end of the upward frequency adjustment unit (120U) and serves to fix the tunable bar (100) to the filter body (10) or filter tuning cover (20) corresponding to the peripheral edge end of the tuning hole (25) by various joining methods including a soldering method.

[0066] The filter (1) for a communication device according to the present invention can adjust the frequency upward or downward by changing the shape of at least one of the upward frequency adjustment unit (120U) and the downward frequency adjustment unit (120D) of the tunable bar (100) to adjust the capacitance, which is an electrical property, within the cavity (C).

[0067] Hereinafter, the features of the tunable bars (100A to 100D) according to the first to fourth implementation examples will be described in detail.

[0068] First, as referenced in FIG. 2A, the tunable bar (100A) according to the first implementation example may be formed in a cylindrical shape with the same inner diameter for the remaining portion except for the joint flange (110) portion, and the bottom portion accommodated in the cavity (C) may be formed to be shielded to form a downward tuning surface (120B). Here, the downward frequency adjustment unit (120D) and the upward frequency adjustment unit (120U) may be defined as a portion close to the cavity (C) based on an arbitrary dividing point (refer to the horizontal dotted line) without a physical distinction in appearance, and the upward frequency adjustment unit (120U) may be defined as a portion between the joint flange (110).

[0069] Since the inner diameters of the remaining parts except for the joint flange (110) portion are the same, the downward frequency adjustment unit (120D) and the upward frequency adjustment unit (120U) may have the same diameters. Here, in the tunable bar (100A) according to the first embodiment, the joint flange (110) is hung on the outside of the tuning hole (25), so that the outer diameter of the joint flange (110) is formed to be larger than the tuning hole (25), and the outer diameters of the downward frequency adjustment unit (120D) and the upward frequency adjustment unit (120U) may be formed to be smaller than the inner diameter of the tuning hole (25).

[0070] In addition, as referenced in FIG. 2B, the tunable bar (100B) according to the second implementation example may be formed so that the joint flange (110), the upward frequency adjustment unit (120U), and the downward frequency adjustment unit (120D) are externally distinct. More specifically, the joint flange (110) and the upward frequency adjustment unit (120U) are formed so that their inner diameters or diameters are different from each other, like the tunable bar (100A) according to the first implementation example described above, and the diameters of the upward frequency adjustment unit (120U) and the downward frequency adjustment unit (120D) may also be formed so that they are externally distinct from each other by being stepped differently from each other. Here, the diameter of the downward frequency adjustment unit (120D) may be formed relatively smaller than the diameter of the upward frequency adjustment unit (120U). Therefore, in the tunable bar (100B) according to the second implementation example, the outer diameter of the joint flange (110) is formed to be larger than the tuning hole (25), and the outer diameter of the upward frequency adjustment unit (120U) is formed to be smaller than the inner diameter of the tuning hole (25), but can be formed to be larger than the outer diameter of the downward frequency adjustment unit (120D).

[0071] In addition, as referenced in FIG. 2c, the tunable bar (100C) according to the third implementation example is formed so that the external appearances of the joint flange (110) and the upward frequency adjustment unit (120U) and the downward frequency adjustment unit (120D) are distinct, and the downward frequency adjustment unit (120D) can also be formed so that the external appearance is distinct by being formed in a stepped form with different diameters by a single step portion. More specifically, the joint flange (110) and the upward frequency adjustment unit (120U) are formed to have different inner diameters or diameters like the tunable bars (100A, 100B) according to the first and second implementation examples described above, and are distinguished from each other, and the diameters of the upward frequency adjustment unit (120U) and the downward frequency adjustment unit (120D) are also formed to have different steps from each other so as to be distinguished externally, and the downward frequency adjustment unit (120D) can also be formed to have different diameters again within a predetermined range above and below so as to be distinguished externally.

[0072] And, as referenced in FIG. 2D, the tunable bar (100D) according to the fourth embodiment may be provided with an upward frequency adjustment unit (120U) in a cone shape whose diameter gradually decreases as it goes toward the downward frequency adjustment unit (120D) having the cavity (C). Here, the tunable bar (100D) according to the fourth embodiment is formed so that the diameter continuously decreases from the upper end of the upward frequency adjustment unit (120U) to the lower end of the downward frequency adjustment unit (120D), so that the upward frequency adjustment unit (120U) and the downward frequency adjustment unit (120D) are not distinguished externally, but the upper end may be defined as the upward frequency adjustment unit (120U) based on an arbitrary line in an upper and lower range greater than the thickness of the filter body (10) or the filter tuning cover (20), and the lower end may be defined as the downward frequency adjustment unit (120D) based on the arbitrary line.

[0073] Typically, a filter made of metal is manufactured to be positioned upward from the target frequency, and the frequency is adjusted by downwardly adjusting the resonant frequency of the filter using a tuning screw or the like. In contrast, in the filter for a communication device of the present invention, when a frequency tuning designer (hereinafter referred to as “designer”) expands and deforms the inner surface (inner surface) of the downward frequency adjustment part (120D) outward using a tuning tool (not shown), the area increases accordingly, the capacitance changes, and the frequency is downwardly adjusted. If necessary, the downward tuning surface (120B), which corresponds to the horizontal plane of the downward frequency adjustment part (120D), can be pressed (or struck) using a tuning tool (not shown) to reduce the distance from the resonant disk panel (32) of the resonator (30), thereby downwardly adjusting the frequency.

[0074] In the above-described frequency downward adjustment process, if the frequency is adjusted downward more than the target frequency, the designer can finely adjust the frequency upward by applying an external force in an outward direction to the inner surface (inner side) corresponding to the upward frequency adjustment part (120U) using a tuning tool. When the inner surface (inner side) corresponding to the upward frequency adjustment part (120U) is deformed, the distance (interval) between the inner surface (inner side) corresponding to the upward frequency adjustment part (120U) and the filter tuning cover becomes closer, thereby changing the capacitance and raising the frequency accordingly.

[0075] Meanwhile, as referenced in (a) of FIG. 2a, the joint flange (110) portion of the tunable bar (100) may be attached to the peripheral edge portion of the tuning hole (25) of the filter body (10) or the filter tuning cover (20) and then joined in various ways, including a soldering method.

[0076] At this time, a plurality of welded portions (115) cut in an arc shape are formed in the joint flange (110) spaced apart from each other in the circumferential direction, and by applying solder material to the welded portions (115), the tunable bar (100) can be firmly fixed to the filter tuning cover (20) (see FIG. 2a).

[0077] Meanwhile, a filter (1) for a communication device according to one embodiment of the present invention may further include a tunable bar (100E) according to a fifth implementation example, which includes a joining flange (110) that is joined by being hooked to the outer edge of a tuning hole (25) of a filter body (10) or a filter tuning cover (20), a downward frequency adjustment unit (120D) that extends into a cavity (C) of the filter body (10) and includes a downward tuning surface (120B) that is arranged parallel to a resonant disk panel (32) of a resonator (30), an upward frequency adjustment unit (120U) that is defined as the upper portion of the downward frequency adjustment unit (120D), and a separation unit (111) that connects the upper end of the upward frequency adjustment unit (120U) and the joining flange (110), as shown in FIG. 2E.

[0078] Here, as referenced in FIG. 2e, the tunable bar (100E) according to the fifth implementation example can be formed so that the space between the inner end forming the tuning hole (25) and the outer end of the filter body (10) or the filter tuning cover (20) is further extended by the spacer (111) described above, so as to further increase and maximize the formation area of ​​the internal capacitance described above.

[0079] More specifically, in the tunable bar (100E) according to the fifth embodiment, assuming that the joining flange (110) is formed in a folded manner parallel to the outer surface of the filter body (10) or the filter tuning cover (20) corresponding to the outer edge end of the tuning hole (25), the separation portion (111) that performs an internal capacitance function by extending a predetermined length outwardly parallel to the inner edge end of the tuning hole (25) from at least the upper end of the upward frequency adjustment portion (120U) can be formed to protrude further outward than the outer surface of the filter body (10) or the filter tuning cover (20).

[0080] At this time, the tunable bar (100E) according to the fifth embodiment may be soldered using a solder material applied between the outer end of the joint flange (110) and the outer surface of the filter body (10) or the filter tuning cover (20), similar to the tunable bars (100A to 100D) according to the first to fourth embodiments, although not shown in the drawing.

[0081] Meanwhile, the tunable bar (100E) according to the fifth implementation example is formed on a downward tuning surface (120B) corresponding to a downward frequency adjustment section (120D), and a frequency measurement hole (120h) formed in communication with a cavity (c) to enable measurement by a frequency measurement device (not shown) between the resonator (30) and the frequency adjustment by the designer can be formed in the form of a boss hole or a through-hole.

[0082] Such a frequency measurement hole (120h) is preferably formed in the center of the downward tuning surface (120B), and can be formed in the same manner not only in the tunable bars (100A to 100D) according to the first to fourth implementation examples described above, but also in the tunable bars (100F, 100G) according to the sixth and seventh implementation examples described below.

[0083] A filter (1) for a communication device according to one embodiment of the present invention may further include a tunable bar (100F, 100G) according to the sixth and seventh embodiments, which includes a joining flange (110') that is forcibly fitted into the inner circumference of a tuning hole (25) of a filter body (10) or a filter tuning cover (20), a downward frequency tuning part (120D) that extends into a cavity (C) of the filter body (10) and includes a downward tuning surface (120B) that is arranged parallel to a resonant disk panel (32) of a resonator (30), an upward frequency tuning part (120U) that is defined as an upper portion of the downward frequency tuning part (120D), and a separation part (111) that connects the upper end of the upward frequency tuning part (120U) and the joining flange (110'), as shown in FIGS. 2F and 2G.

[0084] Here, as referenced in FIGS. 2F and 2G, the tunable bar (100F, 100G) according to the sixth and seventh implementation examples may be defined as an embodiment in which the joining flange (110') is formed by bending parallel to the upward frequency adjustment unit (120U), and the outer surface is formed to be joined to the inner circumference of the tuning hole (25) formed in the filter body (10) or the filter tuning cover (20).

[0085] In the case of the tunable bars (100A to 100E) according to the first to sixth implementation examples referenced in FIGS. 2A to 2E, the joint flange (110) is formed in a circular shape larger than the tuning hole (25), so it may be difficult to precisely match and fix the center of the tunable bars (100A to 100E) with the center of the resonant disk panel (32). In contrast, in the case of the tunable bars (100F, 100G) according to the sixth and seventh implementation examples, the joint flange (110') is designed to be directly fitted into the inner circumference of the tuning hole (25), so that the center of the tunable bars (100F, 100G) can be fixed to match the center of the resonant disk panel (32) within the cavity (C) only by the fitting action thereof.

[0086] At this time, a plurality of cutting portions (112) cut downwardly may be formed spaced apart in the circumferential direction on the joint flange (110') so that a predetermined tension force is continuously provided to the inner circumference of the tuning hole (25) after being forcibly fitted into the tuning hole (25) of the filter body (10) or the filter tuning cover (20).

[0087] In addition, at least two frequency adjustment protrusions (125P) protruding to a predetermined depth from the inner center may be further formed in the portion corresponding to the upward frequency adjustment unit (120U). Referring to FIGS. 2F and 2G, the tunable bars (100F, 100G) according to the sixth and seventh implementation examples are illustrated and described as having four frequency adjustment protrusions (125P) spaced 90 degrees apart from each other in the circumferential direction, but this is not necessarily limited to the present invention, and an appropriate number that is advantageous in terms of external deformation of the tunable bars (100F, 100G) may be employed.

[0088] The designer can adjust the frequency upward by using a tuning tool to change the external shape by pushing the frequency adjustment protrusion (125P) formed protruding inward in an outward direction.

[0089] Meanwhile, as referenced in FIG. 2g, the tunable bar (100G) according to the seventh embodiment is formed so that the joint flange (110') is forcibly fitted into the inner circumference of the tuning hole (25) in the same manner as the tunable bar (100F) according to the sixth embodiment described above, and the outer surface of the joint flange (110') in contact with the inner circumference of the tuning hole (25) is formed by knurling processing so that the adhesion and fixing force can be further enhanced (refer to the drawing reference numeral '110'-1' of FIG. 2g).

[0090] Here, in the area corresponding to the upward frequency adjustment unit (120U), a plurality of frequency adjustment slits (125s) that are formed long in the vertical direction and penetrate inside and outside are formed spaced apart in the circumferential direction, and the designer can upwardly adjust the frequency by changing the external shape using a tuning tool (not shown) that is caught through the frequency adjustment slits (125s).

[0091] At this time, the tunable bar (100F) according to the sixth implementation example and the tunable bar (100G) according to the seventh implementation example can be soldered together using a solder material applied between the outer edge of the tuning hole (25) of the separation portion (111) and the filter tuning cover (20), although not shown in the drawing.

[0092] FIG. 3 is a cross-sectional view showing downward adjustment (a) and upward adjustment (b) of frequency tuning using a tunable bar in the configuration of FIG. 1, FIG. 4 is a cross-sectional view showing a modified example of a filter tuning cover in the configuration of FIG. 1, and FIG. 5 is a cross-sectional view showing upward adjustment of frequency tuning using various upward adjustment tools.

[0093] The frequency tuning design and the frequency modification process after tuning using the downward frequency adjustment unit (120D) and upward frequency adjustment unit (120U) of the tunable bar (100) implemented in various implementation examples as described above are described below with reference to the attached drawings (particularly, FIG. 3). FIG. 3 illustrates the frequency tuning design and the frequency modification process after tuning based on the tunable bar (100D) according to the fourth implementation example, but the same principle can be applied to the tunable bar (100) according to other implementation examples.

[0094] As referenced in (a) of Fig. 3, the frequency tuning operation of a specific cavity (C) is performed by changing the capacitance through downward shape deformation (if necessary) of the inner surface (inner surface) of the downward frequency adjustment section (120D) and / or the downward tuning surface (120B) using a predetermined tuning tool (not shown), thereby downwardly adjusting the frequency.

[0095] At this time, the distance (D1) between the lower surface of the tunable bar (100D) and the resonant disk panel (32) may be a preset value that represents the frequency characteristics required by the designer. A worker performing frequency adjustment or an automatic tuning device may apply an external force to the inner surface (inner surface) of the downward frequency adjustment unit (120D) and / or the downward tuning surface (120B) until the above-described D1 value is reached, thereby causing a shape deformation to reach the D1 value, and store the result value when the desired value is reached.

[0096] However, if the shape is deformed more downward than the D1 value, a frequency tuning correction process must be performed, and the worker or automatic tuning device performing the frequency correction can, as referenced in (b) of FIG. 3, apply an external force to the inner surface of the upward frequency adjustment unit (120U) to form a tuning correction point (120P2) to deform the shape until the D2 value is reached, while simultaneously strengthening the capacitance with the filter tuning cover (20) to weaken the capacitance corresponding to the D1 value, thereby moving the frequency upward.

[0097] However, the frequency correction process does not necessarily have to be carried out only through external force on the upward frequency adjustment unit (120) described above, and when the frequency correction process described above is carried out, a correction point (120P1) may be formed in the area corresponding to the downward frequency adjustment unit (120D), causing an upward shape deformation.

[0098] Meanwhile, the tuning hole (25) formed in the filter body (10) or the filter tuning cover (20) for installation of the tunable bar (100D) may include a tapered end (27) formed so that the diameter gradually increases toward the inside of the cavity (C), as shown in FIG. 4.

[0099] By securing a sufficient distance from the outer surface of the upward frequency adjustment section (120U) of the tunable bar (100D) by the taper section (27), it has the advantage of being able to easily utilize the internal capacitance.

[0100] In addition, frequency tuning correction through the upward frequency adjustment unit (120U) of the above-described tunable bar (100D) can be performed using a rotary compression jig (200-1) or an expansion compression jig (200-2), as referenced in (a) and (b) of FIG. 5.

[0101] More specifically, as referenced in (a) of FIG. 5, frequency tuning correction through the upward frequency adjustment part (120U) of the tunable bar (100D) can be performed by slightly raising the lower surface of the tunable bar (100D) while causing an external deformation such as a correction point (120P2) by rotating a rotating press jig (200-1) in which a jig tip (210) that applies an external force to the inner surface corresponding to the upward frequency adjustment part (120U) is bent.

[0102] In addition, as referenced in (b) of FIG. 5, frequency tuning correction through the upward frequency adjustment unit (120U) of the tunable bar (100D) can be performed by slightly raising the lower surface of the tunable bar (100D) while causing an external deformation such as a correction point (120P2) on both sides by an expanded compression jig (200-2) in which the compression tips (220) that are spaced apart from each other after being introduced into the interior of the upward frequency adjustment unit (120U) are arranged to spread toward two or more points of the upward frequency adjustment unit (120U).

[0103] In one embodiment of the present invention, the tunable bar (100D) is preferably made of a metal material that is easy to deform, such as aluminum or copper, so that the external shape of the upward frequency adjustment unit (120U) can be easily changed as described above.

[0104] The filter (1) for a communication device according to one embodiment of the present invention can completely eliminate the phenomenon of incomplete contact between the filter tuning cover (20) and the tunable bar (100D), thereby not only improving the PIMD problem that reduces the performance of the filter, but also providing the advantage of reducing the production (manufacturing) cost of the product because a separate tuning screw (not shown) or additional structure (e.g., a fixing nut for fixing the tuning screw) is not required.

[0105]

[0106] Above, a filter for a communication device according to one embodiment of the present invention has been described in detail with reference to the attached drawings. However, the embodiments of the present invention are not necessarily limited to the above-described embodiments, and it will be understood that various modifications and equivalent implementations are possible by those skilled in the art to which the present invention pertains. Therefore, the true scope of the present invention is defined by the claims set forth below.

Claims

1. A filter body having at least one cavity formed inside; At least one resonator having a tip extending a predetermined length from one side of the bottom surface of the filter body corresponding to the bottom surface of the cavity to the other side; and A filter for a communication device, comprising: a tunable bar, which is coupled to each of a plurality of tuning holes formed in the filter body so as to correspond to each of the cavities, and which causes a shape deformation of an outer surface of a portion exposed into the cavity, including a portion corresponding to a range in the thickness direction of the tuning hole, thereby enabling frequency adjustment; 2. In claim 1, The above tunable bar is, A joining flange that is engaged with the outer edge of the above tuning hole; A downward frequency tuning unit extending from the above-mentioned joining flange through the above-mentioned tuning hole into the cavity of the above-mentioned filter body and including a downward tuning surface arranged parallel to a resonant disk panel provided in the above-mentioned resonator; and A filter for a communication device, comprising: an upward frequency adjustment unit defined between the downward frequency adjustment unit and the joint flange; 3. In claim 2, A filter for a communication device, wherein the above-mentioned downward frequency adjustment unit and the above-mentioned upward frequency adjustment unit are formed to have the same diameter, but are spaced apart from the inner end of the tuning hole and parallel to it.

4. In claim 2, A filter for a communication device, wherein the downward frequency adjustment unit is formed to have a smaller diameter than the upward frequency adjustment unit, but is formed to have a step with respect to the upward frequency adjustment unit.

5. In claim 2, A filter for a communication device, wherein the above-mentioned upward frequency adjustment unit is formed so that its diameter gradually decreases as it goes toward the inside of the cavity.

6. In claim 2, A filter for a communication device, wherein the tuning hole corresponding to the position of the upward frequency adjustment unit includes a tapered end formed so that the diameter gradually increases toward the cavity side.

7. In claim 2, A filter for communication devices, wherein a frequency measurement hole communicating with the cavity is further formed at the center of the above downward tuning surface.

8. In claim 2, A filter for communication devices, wherein frequency tuning correction through the upward frequency adjustment section of the tunable bar is performed by a rotating press jig that rotates after being introduced into the interior of the upward frequency adjustment section and then deforms the inner surface of the upward frequency adjustment section outward.

9. In claim 2, A filter for communication devices, wherein frequency tuning correction through the upward frequency adjustment section of the tunable bar is performed by an expansion compression jig that is introduced into the interior of the upward frequency adjustment section and then spreads outwardly toward two or more points of the upward frequency adjustment section, thereby deforming the inner surface of the frequency adjustment section outward.

10. In claim 2, Frequency adjustment within the cavity is achieved by deformation of the inner surface or downward tuning surface of the downward frequency adjustment unit. A filter for communication devices, wherein the frequency adjusted by the above-mentioned downward frequency adjustment unit is modified by deformation of the inner surface of the above-mentioned upward frequency adjustment unit.

11. In claim 1, The above tunable bar is, A joining flange that is forcibly fitted into the inner circumference of the above tuning hole; A filter for a communication device, wherein the above-mentioned joining flange has a plurality of cut portions formed in a circumferential direction so that a predetermined tension force is continuously provided to the inner circumference of the tuning hole after being forcibly fitted into the tuning hole.

12. In claim 11, A filter for communication devices, wherein the outer surface of the above-mentioned joint flange is formed by knurling processing.

13. In claim 2, A filter for a communication device, wherein at least two frequency adjustment protrusions protrude to a predetermined depth from the inner center in a portion corresponding to the above-mentioned upward frequency adjustment section.

14. In claim 2, A filter for communication devices, wherein a plurality of frequency adjustment slits are formed in a circumferential direction, extending upward and downward, and penetrating internally and externally in a portion corresponding to the above-mentioned upward frequency adjustment section.

15. In claim 2, Further comprising a separation portion connecting the upper portion of the upward frequency adjustment portion and the joining flange; A filter for a communication device, wherein the above-mentioned separation portion is formed to protrude further in the outer direction of the tuning hole.

16. In claim 2 or claim 11, A filter for a communication device, wherein the above tuning hole is formed in a filter tuning cover provided to cover the open other side of the filter body.

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