duplexer

Abstract

A duplexer includes a cavity, a tuning assembly, and a resonant assembly. The resonant assembly includes four integrated plates arranged front-to-back and left-to-right within the tuning cavity. The four integrated plates include a first plate extending left-to-front and left-to-right, a second plate extending right-to-front and left-to-right, a third plate extending left-to-rear and left-to-right, and a fourth plate extending right-to-rear and left-to-right. Each integrated plate includes multiple resonant units spaced apart left-to-right. Any two adjacent resonant units of each integrated plate have an inductive coupling structure. At least two adjacent resonant units of each integrated plate have a capacitive coupling structure. Each integrated plate has at least one cross-coupling structure located between two non-adjacent resonant units. Each integrated plate has several branches on its side to form a low-pass filter. This invention features a simplified product structure, and its manufacturing and installation processes are very simple.

Description

Technical Field

[0001] This utility model relates to the field of cavity filters, and in particular to a duplexer. Background Technology

[0002] Cavity filters are limited by the frequency of the circular resonant unit, making it impossible to achieve the design requirement of smaller filter size. Existing sheet metal duplexers have complex cavity structures, a variety of materials, including PEEK screws, passivated screws, and silver-plated screws. The flying rod and resonant plate are installed using various screws, resulting in a complex assembly process. Utility Model Content

[0003] The purpose of this utility model is to provide a duplexer with a simplified product structure, which avoids the installation of screws between resonators, etc., and the process is simple.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a duplexer, comprising:

[0005] The cavity includes a top wall, a bottom wall, and a side wall. The upper end of the side wall is connected to the top wall, and the lower end is connected to the bottom wall. At least one of the top wall and the bottom wall is separably connected to the side wall. The top wall, the bottom wall, and the side wall enclose a frequency modulation cavity.

[0006] An adjusting screw assembly is positioned on the top wall, and the adjusting screw assembly includes an adjustable screw that can be inserted into the frequency tuning chamber for frequency adjustment;

[0007] A resonant assembly, positioned on the bottom wall, comprises four integrated plates arranged front-to-back and left-to-right within the frequency modulation cavity. The four integrated plates include a first plate extending left-to-front and left-to-right, a second plate extending right-to-front and left-to-right, a third plate extending left-to-rear and left-to-right, and a fourth plate extending right-to-rear and left-to-right. Each integrated plate includes multiple resonant units spaced left-to-right. Any two adjacent resonant units of each integrated plate have an inductive coupling structure, at least two adjacent resonant units of each integrated plate have a capacitive coupling structure, and each integrated plate has at least one cross-coupling structure located between two non-adjacent resonant units. Each integrated plate has several branches on its main body to form a low-pass filter.

[0008] As a further improvement of the present invention, the low-pass filter on the first plate is a branch extending from the resonant unit on the first plate near the second plate, the low-pass filter on the second plate is a branch extending from the resonant unit on the second plate near the first plate, the low-pass filter on the third plate is a branch extending from the resonant unit on the third plate near the fourth plate, and the low-pass filter on the fourth plate is a branch extending from the resonant unit on the fourth plate near the third plate.

[0009] As a further improvement of the present invention, the low-pass filter includes a horizontal branch and a vertical branch. The horizontal branch is integrally connected to the resonant unit closest to the center of the frequency modulation chamber of each integrated board, and the vertical branch is integrally formed on the upper and lower sides corresponding to the horizontal branch.

[0010] As a further improvement of the present invention, the bottom wall is provided with two port support seats, the vertical branch of the second plate and the vertical branch of the fourth plate are respectively connected to one of the port support seats, the horizontal branch of the first plate is welded to the vertical branch of the second plate, and the horizontal branch of the third plate is welded to the vertical branch of the fourth plate.

[0011] As a further improvement of the present invention, the inductive coupling structure is an inductive coupling rib, one end of which is integrally connected to one of the two adjacent resonant units of the same integrated board, and the other end of which is integrally connected to the other of the two adjacent resonant units of the same integrated board.

[0012] As a further improvement of the present invention, two adjacent resonant units of the same integrated board have a first branch located in one of the resonant units and a second branch located in the other resonant unit. The first branch and the second branch extend toward each other and are staggered vertically to form the capacitive coupling structure.

[0013] As a further improvement of the present invention, the cross-coupling structure is a cross-coupling rib, one end of which is welded to one of the two non-adjacent resonant units on the same integrated board, and the other end of which is welded to the other of the two non-adjacent resonant units on the same integrated board.

[0014] As a further improvement of this utility model, it also includes a partition rib. The sidewall includes a left sidewall and a right sidewall arranged opposite to each other, and a front sidewall and a rear sidewall arranged opposite to each other. The partition rib is laterally arranged between the left sidewall and the right sidewall. The partition rib protrudes from one of the top wall and the bottom wall toward the other. The partition rib divides the frequency modulation chamber into a first chamber and a second chamber. The first plate and the second plate are disposed in the first chamber with their left and right sides grounded, and the third plate and the fourth plate are disposed in the second chamber with their left and right sides grounded.

[0015] As a further improvement of the present invention, the rib is broken at a position near the left side wall to form a first channel and at a position near the right side wall to form a second channel. The duplexer includes a first filter located on the left and a second filter located on the right. The filtered signals between the first plate and the third plate are connected in the first channel to form the first filter, and the filtered signals between the second plate and the fourth plate are connected in the second channel to form the second filter.

[0016] As a further improvement of the present invention, it also includes a number of fasteners. The side wall facing the bottom wall is provided with a number of first positioning holes, and the bottom wall is provided with a number of second positioning holes corresponding to the first positioning holes. The fasteners are positioned in the first positioning holes and the second positioning holes in a one-to-one correspondence.

[0017] As a further improvement of the present invention, the first positioning hole is a blind hole and the second positioning hole is a through hole, and the fastener is a fastening screw that passes through the second positioning hole and is locked in the first positioning hole.

[0018] As a further improvement of the present invention, the first plate, the second plate, the third plate and the fourth plate are all, and simultaneously, one of sheet metal parts and plastic parts.

[0019] Compared to existing technologies, this invention, by providing multiple resonant units spaced apart on the left and right sides on each integrated board, also includes an inductive coupling structure, a capacitive coupling structure, a cross-coupling structure, and a low-pass filter. Therefore, each board in this duplexer has a simplified product structure, avoiding the need for screws in the installation of the resonant units, inductive coupling structure, capacitive coupling structure, cross-coupling structure, and low-pass filter, thus simplifying the manufacturing process. Attached Figure Description

[0020] Figure 1 This is a three-dimensional assembly diagram of the duplexer of this utility model;

[0021] Figure 2This is an exploded perspective view of the duplexer of this utility model;

[0022] Figure 3 This is a further exploded perspective view of the duplexer of this utility model;

[0023] Figure 4 This is an exploded perspective view of the duplexer of this utility model from another angle;

[0024] Figure 5 This is a three-dimensional assembly diagram of the four plates of the duplexer of this utility model installed on the bottom wall, excluding the top wall and side wall;

[0025] Figure 6 yes Figure 5 3D exploded view;

[0026] Figure 7 yes Figure 5 Top view;

[0027] Figure 8 yes Figure 5 A 3D view of the first component in the middle;

[0028] Figure 9 yes Figure 5 A three-dimensional view of the second panel in the middle;

[0029] Figure 10 yes Figure 5 3D view of the third component;

[0030] Figure 11 yes Figure 5 3D view of the fourth panel in the middle;

[0031] Figure 12 This is a bottom view of the cavity of the duplexer of this utility model, excluding the bottom wall;

[0032] Figure 13 This is a bottom view of the cavity containing the four plates of the duplexer of this utility model, excluding the bottom wall and only including the top and side walls. Detailed Implementation

[0033] The exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. If several embodiments exist, features in these embodiments may be combined with each other without conflict. When the description refers to the drawings, unless otherwise stated, the same numbers in different drawings represent the same or similar elements. The descriptions in the following exemplary embodiments do not represent all embodiments consistent with the present invention; rather, they are merely examples of apparatuses, products, and / or methods consistent with some aspects of the present invention as set forth in the claims.

[0034] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the scope of protection of this invention. The singular forms “a,” “the,” or “the” used in the specification and claims of this invention are also intended to include the plural forms unless the context clearly indicates otherwise.

[0035] It should be understood that the terms "first," "second," and similar words used in the specification and claims of this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish the features. Similarly, the terms "an" or "a" do not indicate a quantity limitation, but rather indicate the presence of at least one. Unless otherwise stated, the terms "front," "back," "left," "right," "upper," "lower," and similar words appearing in this utility model are for ease of explanation only and are not limited to a specific location or spatial orientation. The terms "comprising" or "including" are an open-ended expression, meaning that the element preceding "comprising" or "including" covers the element following "comprising" or "including" and its equivalents, which does not exclude that the element preceding "comprising" or "including" may also include other elements. If "several" appears in this utility model, it means two or more.

[0036] Please refer to Figures 1 to 13 As shown, this utility model discloses a duplexer 100, which includes a cavity 1, a screw adjusting assembly 2, and a resonant assembly 3.

[0037] Please refer to Figures 2 to 4 As shown, the cavity 1 includes a top wall 11, a bottom wall 12, and a side wall 13. The upper end of the side wall 13 is connected to the top wall 11, and the lower end is connected to the bottom wall 12. The top wall 11, the bottom wall 12, and the side wall 13 enclose a frequency tuning chamber 10. At least one of the top wall 11 and the bottom wall 12 is detachably connected to the side wall 13, so that at least one of the top wall 11 and the bottom wall 12 can be opened relative to other parts of the cavity 1. For example, the top wall 11 can be opened relative to the bottom wall 12 and the side wall 13, or the bottom wall 12 can be opened relative to the top wall 11 and the side wall 13, or the top wall 11 and the bottom wall 12 can be opened simultaneously relative to the side wall 13. With this configuration, the resonant assembly 3 can be accommodated in the frequency tuning chamber 10.

[0038] Please refer to Figure 2 and Figure 3 As shown, the adjusting screw assembly 2 is positioned on the top wall 11, and the adjusting screw assembly 2 includes an adjustable screw 21 that can be inserted into the frequency tuning chamber 10 for frequency adjustment.

[0039] Please refer to Figures 2 to 11 As shown, the resonant assembly 3 is positioned on the bottom wall 12. The resonant assembly 3 includes four integrated plates 30 arranged in a front-back, left-right, and right-back configuration within the frequency modulation chamber 10. The four integrated plates 30 include a first plate 301 located at the front left and extending left and right, a second plate 302 located at the front right and extending left and right, a third plate 303 located at the rear left and extending left and right, and a fourth plate 304 located at the rear right and extending left and right. Each integrated plate 30 includes a plurality of resonant units 300 spaced apart from each other. Any two adjacent resonant units 300 of each integrated plate 30 have an inductive coupling structure 4. At least two adjacent resonant units 300 of each integrated plate 30 have a capacitive coupling structure 5. Each integrated plate 30 has at least one cross-coupling structure 6 located between two non-adjacent resonant units 300. Each integrated plate 30 has several branches on its main body to form a low-pass filter 7. With this configuration, in addition to multiple resonant units 300 spaced apart on the left and right sides, each integrated board 30 of this invention also has an inductive coupling structure 4, a capacitive coupling structure 5, a cross-coupling structure 6, and a low-pass filter 7. Therefore, each integrated board 30 in the duplexer of this invention has a simplified product structure, avoiding the need for screws to be installed between the resonant units 300, the inductive coupling structure 4, the capacitive coupling structure 5, the cross-coupling structure 6, and the low-pass filter 7, thus simplifying the manufacturing process.

[0040] Please refer to Figures 5 to 11 As shown, the low-pass filter 7 on the first plate 301 is a branch extending from the resonant unit 300 on the first plate 301 near the second plate 302; the low-pass filter 7 on the second plate 302 is a branch extending from the resonant unit 300 on the second plate 302 near the first plate 301; the low-pass filter 7 on the third plate 303 is a branch extending from the resonant unit 300 on the third plate 303 near the fourth plate 304; and the low-pass filter 7 on the fourth plate 304 is a branch extending from the resonant unit 300 on the fourth plate 304 near the third plate 303. With this arrangement, the low-pass filter 7 can be positioned closest to the center of the frequency modulation chamber 10 rather than on the left or right sides. Therefore, the existing usable space of the frequency modulation chamber 10 is effectively utilized without increasing its area, resulting in a compact product structure.

[0041] Please refer to Figures 8 to 11As shown, each low-pass filter 7 includes a horizontal branch 71 and a vertical branch 72. The horizontal branch 71 is integrally connected to the resonant unit 300 closest to the center of the frequency modulation chamber 10 on each integrated board 30. The vertical branch 72 is integrally formed on the upper and lower sides corresponding to the horizontal branch 71. This arrangement of the low-pass filter 7 effectively utilizes the horizontal space in the left-right direction and the vertical space in the up-down direction, achieving the low-pass functionality of the product while maintaining a compact product structure.

[0042] Please refer to Figures 3 to 5 as well as Figure 7 As shown, the bottom wall 12 is provided with two port support seats 8. The vertical branch 72 of the second plate 302 and the vertical branch 72 of the fourth plate 304 are respectively connected to one of the port support seats 8. The horizontal branch 71 of the first plate 301 is welded to the vertical branch 72 of the second plate 302, and the horizontal branch 71 of the third plate 303 is welded to the vertical branch 72 of the fourth plate 304. This arrangement allows the two filters on the left and right sides (the first filter 1001 on the left and the second filter 1002 on the right, as described below) to share one input port and one output port, realizing the input / output function of the duplexer 100 of this utility model with the external structure.

[0043] Please refer to Figures 8 to 11 As shown, the inductive coupling structure 4 is an inductive coupling rib. One end of the inductive coupling rib is integrally connected to one of the two adjacent resonant units 300 of the same integrated board 30, and the other end of the inductive coupling rib is integrally connected to the other of the two adjacent resonant units 300 of the same integrated board 30. This configuration of the inductive coupling structure 4 makes it simple to manufacture, easy to implement, and effectively connects two adjacent resonant units 300 into one unit.

[0044] Please refer to Figures 8 to 11 As shown, two adjacent resonant units 300 of the same integrated board 30 have a first branch 51 located in one of the resonant units 300 and a second branch 52 located in the other resonant unit 300. The first branch 51 and the second branch 52 extend towards each other and are staggered vertically to form the capacitive coupling structure 5. This arrangement of the capacitive coupling structure 5 makes the process simple and easy to implement; and it can effectively utilize the space between two adjacent resonant units 300.

[0045] Please refer to Figures 8 to 11As shown, the cross-coupling structure 6 is a cross-coupling rib. One end of the cross-coupling rib is welded to one of the two non-adjacent resonant units 300 on the same integrated board 30, and the other end of the cross-coupling rib is welded to the other of the two non-adjacent resonant units 300 on the same integrated board 30. This configuration of the cross-coupling structure 6 further enables cross-coupling based on the aforementioned inductive and capacitive coupling; simultaneously, it simplifies the manufacturing process of the cross-coupling structure 6 and makes it easy to implement.

[0046] Please refer to Figure 4 , Figure 12 and Figure 13 As shown, the frequency modulation chamber 10 also includes a partition 14. In a specific embodiment, the top wall 11 and the side wall 13 are integrally formed, and the partition 14 is integrally formed on the side of the top wall 11 facing the bottom wall 12 and protrudes towards the bottom wall 12. The side wall 13 includes a left side wall 131 and a right side wall 132 arranged opposite each other, and a front side wall 133 and a rear side wall 134 arranged opposite each other. The partition 14 is laterally arranged between the left side wall 131 and the right side wall 132. The partition 14 protrudes from one of the top wall 11 and the bottom wall 12 towards the other, and the partition 14 divides the frequency modulation chamber 10 into a first chamber 101 and a second chamber 102. The first plate 301 and the second plate 302 are disposed side-by-side in the first chamber 101, and the third plate 303 and the fourth plate 304 are disposed side-by-side in the second chamber 102. The purpose of setting the partition 14 in this way is mainly to divide the frequency modulation chamber 10 in the front and back direction, so as to facilitate the positioning of the first plate 301, the second plate 302, the third plate 303 and the fourth plate 304 respectively.

[0047] Please continue to refer to Figure 4 , Figure 12 and Figure 13 As shown, the partition 14 is broken near the left side wall 131 to form a first channel 141 and near the right side wall 132 to form a second channel 142. The duplexer 100 includes a first filter 1001 on the left and a second filter 1002 on the right. The filtered signal between the first plate 301 and the third plate 303 is connected in the first channel 141 to form the first filter 1001, and the filtered signal between the second plate 302 and the fourth plate 304 is connected in the second channel 142 to form the second filter 1002. This arrangement of the partition 14 not only largely separates the frequency modulation chamber 10 in the front-to-back direction, but also allows for small-scale interconnection in the front-to-back direction, enabling the formation of filtered signals.

[0048] Please refer to Figures 1 to 4 As shown, this utility model also includes several fasteners 9. At least the side wall 13 facing the bottom wall 12 has several first positioning holes 130. In a specific embodiment, the partition rib 14 also has several first positioning holes 130 on the side facing the bottom wall 12. The bottom wall 12 has several second positioning holes 120 corresponding to the first positioning holes 130, and the fasteners 9 are correspondingly positioned within the first positioning holes 130 and the second positioning holes 120. This arrangement of the fasteners 9 allows for quick, convenient, and effective positioning and installation of the bottom wall 12 onto the integrally formed top wall 11 and side wall 13, forming the frequency modulation chamber 10.

[0049] Please refer to Figure 3 and Figure 4 As shown, the first positioning hole 130 is a blind hole and the second positioning hole 120 is a through hole. The fastener 9 is a fastening screw that passes through the second positioning hole 120 and is locked in the first positioning hole 130. By setting the first positioning hole 130 and the second positioning hole 120 in this way, the bottom wall 12 can be positioned and installed quickly, conveniently and effectively, and the positioning and installation can be guaranteed to be firm.

[0050] Please refer to Figures 1 to 13 As shown, the first plate 301, the second plate 302, the third plate 303, and the fourth plate 304 are all, and simultaneously, one of sheet metal parts and plastic parts. In a preferred embodiment, the first plate 301, the second plate 302, the third plate 303, and the fourth plate 304 are all sheet metal parts, which are easier to process and shape and ensure the effect of frequency modulation.

[0051] In summary, each integrated board 30 in this duplexer has a simplified product structure. Specifically, each integrated board 30 has an inductive coupling structure 4 between any two adjacent resonant units 300, a capacitive coupling structure 5 between at least two adjacent resonant units 300, and at least one cross-coupling structure 6 located between two non-adjacent resonant units 300. Each integrated board 30 also has several branches on its side to form a low-pass filter 7. Therefore, this duplexer avoids the need for screws in the installation of the resonant units 300, inductive coupling structure 4, capacitive coupling structure 5, cross-coupling structure 6, and low-pass filter 7, resulting in a simple manufacturing process and good frequency modulation performance.

[0052] The above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. The understanding of the present utility model should be based on those skilled in the art. Although the present utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present utility model. All technical solutions and improvements that do not depart from the spirit and scope of the present utility model should be covered within the scope of the claims of the present utility model.

Claims

1. A duplexer, characterized in that: include: The cavity (1) has a frequency-modulated chamber (10); The adjusting screw assembly (2) includes an adjustable screw (21) that can be inserted into the frequency tuning chamber (10) for frequency adjustment; The resonant assembly (3) includes four integrated plates (30) arranged in a front-back, left-right configuration within the frequency modulation chamber (10). The four integrated plates (30) include a first plate (301) located at the front left and extending left-right, a second plate (302) located at the front right and extending left-right, a third plate (303) located at the rear left and extending left-right, and a fourth plate (304) located at the rear right and extending left-right. Each integrated plate (30) includes multiple resonant units (300) spaced apart from each other. The integrated board (30) has an inductive coupling structure (4) between any two adjacent resonant units (300), and at least two adjacent resonant units (300) of each integrated board (30) have a capacitive coupling structure (5). Each integrated board (30) has at least one cross coupling structure (6) and the cross coupling structure (6) is located between two non-adjacent resonant units (300). Each integrated board (30) has several branches on the side of its main body to form a low-pass filter (7).

2. The duplexer as described in claim 1, characterized in that: The low-pass filter (7) on the first plate (301) is a branch extending from the resonant unit (300) on the first plate (301) near the second plate (302). The low-pass filter (7) on the second plate (302) is a branch extending from the resonant unit (300) on the second plate (302) near the first plate (301). The low-pass filter (7) on the third plate (303) is a branch extending from the resonant unit (300) on the third plate (303). The low-pass filter (7) on the fourth plate (304) is a branch extending from the resonant unit (300) on the fourth plate (304) near the third plate (303).

3. The duplexer as described in claim 2, characterized in that: Each low-pass filter (7) includes a horizontal branch (71) and a vertical branch (72). The horizontal branch (71) is integrally connected to the resonant unit (300) of each integrated board (30) that is closest to the center of the frequency modulation chamber (10). The vertical branch (72) is integrally formed on the upper and lower sides corresponding to the horizontal branch (71).

4. The duplexer as described in claim 3, characterized in that: Two port support bases (8) are also provided. The vertical branch (72) of the second plate (302) and the vertical branch (72) of the fourth plate (304) are respectively connected to one of the port support bases (8). The horizontal branch (71) of the first plate (301) is welded to the vertical branch (72) of the second plate (302). The horizontal branch (71) of the third plate (303) is welded to the vertical branch (72) of the fourth plate (304).

5. The duplexer as described in claim 1, characterized in that: The inductive coupling structure (4) is an inductive coupling rib. One end of the inductive coupling rib is integrally connected to one of the two adjacent resonant units (300) of the same integrated board (30), and the other end of the inductive coupling rib is integrally connected to the other of the two adjacent resonant units (300) of the same integrated board (30).

6. The duplexer as described in claim 1, characterized in that: Two adjacent resonant units (300) of the same integrated board (30) have a first branch (51) in one of the resonant units (300) and a second branch (52) in the other resonant unit (300), the first branch (51) and the second branch (52) extending toward each other and staggered vertically to form the capacitive coupling structure (5).

7. The duplexer as described in claim 1, characterized in that: The cross-coupling structure (6) is a cross-coupling rib. One end of the cross-coupling rib is welded to one of the two non-adjacent resonant units (300) on the same integrated board (30), and the other end of the cross-coupling rib is welded to the other of the two non-adjacent resonant units (300) on the same integrated board (30).

8. The duplexer as described in claim 1, characterized in that: It also includes a partition (14). The cavity (1) includes a top wall (11), a bottom wall (12), and a side wall (13). The upper end of the side wall (13) is connected to the top wall (11), and the lower end is connected to the bottom wall (12). At least one of the top wall (11) and the bottom wall (12) is separably connected to the side wall (13). The top wall (11), the bottom wall (12), and the side wall (13) enclose the frequency modulation chamber (10). The side wall (13) includes a left side wall (131) and a right side wall (132) arranged opposite to each other, and a front side wall (133) and a rear side wall arranged opposite to each other. (134) The partition (14) is arranged laterally between the left side wall (131) and the right side wall (132); the partition (14) protrudes from one of the top wall (11) and the bottom wall (12) toward the other, and the partition (14) divides the frequency modulation chamber (10) into a first chamber (101) and a second chamber (102); the first plate (301) and the second plate (302) are arranged in the first chamber (101) with their left and right sides connected, and the third plate (303) and the fourth plate (304) are arranged in the second chamber (102) with their left and right sides connected.

9. The duplexer as described in claim 8, characterized in that: The rib (14) is broken at a position near the left side wall (131) to form a first channel (141) and at a position near the right side wall (132) to form a second channel (142). The duplexer includes a first filter (1001) located on the left and a second filter (1002) located on the right. The filtered signal between the first plate (301) and the third plate (303) is connected in the first channel (141) to form the first filter (1001). The filtered signal between the second plate (302) and the fourth plate (304) is connected in the second channel (142) to form the second filter (1002).

10. The duplexer as claimed in claim 8, characterized in that: It also includes several fasteners (9), the side wall (13) facing the bottom wall (12) is provided with several first positioning holes (130), the bottom wall (12) is provided with several second positioning holes (120) corresponding to the first positioning holes (130), and the fasteners (9) are correspondingly located in the first positioning holes (130) and the second positioning holes (120).

11. The duplexer as claimed in claim 10, characterized in that: The first positioning hole (130) is a blind hole and the second positioning hole (120) is a through hole. The fastener (9) is a fastening screw that passes through the second positioning hole (120) and is locked in the first positioning hole (130).

12. The duplexer as claimed in claim 1, characterized in that: The first plate (301), the second plate (302), the third plate (303) and the fourth plate (304) are all, and simultaneously, one of sheet metal parts and plastic parts.

Images