Trimming device for surface mount filter

Abstract

This invention provides a fine-tuning device for surface-mount filters, belonging to the technical field of filter manufacturing equipment. It includes a base plate; a loading module connected to the base plate; the loading module having a first through slot for loading a surface-mount filter carrier disk; a micro-motion module including a first stepper motor, a first support base, a disk, a connecting rod, a platform slider, and a slide rail; the first stepper motor is fixed on the first support base and drives the disk to rotate; both ends of the connecting rod are connected to the disk and the platform slider respectively; the first support base and the slide rail are both fixed to the base plate; the platform slider is slidably connected to the slide rail; the disk, connecting rod, and platform slider form a crank-connecting rod mechanism; and a silver spray plate with silver spray holes; the silver spray plate is connected to the platform slider and located directly below the first through slot. This invention overcomes the drawbacks of cumbersome traditional vapor deposition fine-tuning operations, significantly improving the efficiency of vapor deposition fine-tuning of surface-mount filter frequencies, thereby increasing filter production efficiency and reducing production costs.

Description

Technical Field

[0001] This invention belongs to the technical field of filter manufacturing equipment, and more specifically, it relates to a fine-tuning device for a surface mount filter. Background Technology

[0002] Monolithic filters, with their excellent frequency selectivity, high Q value, low insertion loss, and compact size, have been widely used in military, communications, consumer electronics, and various electronic devices. With the continuous development of science and technology, the requirements for miniaturization and domestic production of monolithic filters are becoming increasingly stringent. Surface mount filters are gradually becoming the mainstream in modern electronics manufacturing, and precise frequency adjustment of surface mount filters is a hot topic in research and production both domestically and internationally. To improve the accuracy of surface mount filters, fine-tuning of the quartz crystal oscillator is necessary during the production process. Common methods include ion etching and vapor deposition fine-tuning, which achieve the effect of fine-tuning the quartz crystal frequency by changing the thickness and quality of the electrode film.

[0003] Fine-tuning is a crucial step that directly determines the stability of the frequency and bandwidth of a surface-mount filter. The accuracy and reliability of the fine-tuning process have a decisive impact on the performance of the final product. Furthermore, due to the special nature of surface-mount filters, especially dual-cell products, fine-tuning requires multiple adjustments to each crystal oscillator because it has multiple electrodes. Dual-cell products, with two crystal oscillators, require twice as many adjustments, and each adjustment necessitates manual position control, making the process extremely cumbersome. In addition, vapor deposition fine-tuning requires a vacuum environment. After one crystal in a dual-cell filter is fine-tuned, the filter must be manually flipped to fine-tune the other crystal. This manual flipping requires breaking the vacuum, followed by re-vacuuming before fine-tuning the other crystal, further complicating the vapor deposition fine-tuning process for dual-cell filters.

[0004] However, the lack of such fine-tuning equipment for surface mount filters in China limits further improvements in their performance and also affects production efficiency and cost control. Therefore, it is necessary to design a fine-tuning device for surface mount filters to address the problems existing in the current technology. Summary of the Invention

[0005] The purpose of this invention is to provide a fine-tuning device for surface-mount filters, which automatically adjusts the vapor deposition position during the vapor deposition fine-tuning process, thereby depositing silver plating on the electrodes at different positions on the surface-mount filter to achieve the purpose of fine-tuning the quartz crystal oscillator frequency. The fine-tuning device of this invention can automatically adjust the vapor deposition position, avoiding the tedious operation of traditional manual control of the fine-tuning position, improving the production efficiency of filters and reducing production costs.

[0006] To achieve the above objectives, the present invention provides a fine-tuning device for a surface-mount filter, comprising:

[0007] Base plate;

[0008] A loading module is connected to the base plate; the loading module is provided with a first through slot for loading a surface mount filter carrier disk.

[0009] A micro-motion module includes a first stepper motor, a first support base, a disk, a connecting rod, a platform slider, and a slide rail; the first stepper motor is fixed on the first support base and drives the disk to rotate; the two ends of the connecting rod are respectively connected to the disk and the platform slider; the first support base and the slide rail are both fixed on the base plate; the platform slider is slidably connected to the slide rail; the disk, connecting rod, and platform slider form a crank-connecting rod mechanism; and...

[0010] A silver spray plate is provided with silver spray holes; the silver spray plate is connected to the platform slider and is located directly below the first through slot.

[0011] Furthermore, a fixing rod is connected to the platform slider; one end of the fixing rod passes through a through hole provided on the base plate and is connected to the silver spray plate; a second through groove is provided on the base plate at a position corresponding to the first through groove, and the silver spray plate is located directly below the second through groove.

[0012] Furthermore, the bottom plate has two grooves on its lower side, the silver spray plate is embedded in the grooves on both sides, and the silver spray plate is slidably connected to the grooves.

[0013] Furthermore, multiple silver spray holes are arrayed on the silver spray plate.

[0014] Furthermore, a positioning post is provided in the first through slot, which is used to fix and position the surface mount filter carrier.

[0015] Furthermore, the first support base includes an L-shaped vertical plate and a horizontal plate connected together, the vertical plate being connected to the first stepper motor, and the horizontal plate being connected to the base plate.

[0016] Furthermore, the through hole is an oblong hole.

[0017] Furthermore, it also includes a rotation module, which comprises a second stepper motor, a second support base, and a gear; the second stepper motor is fixed on the second support base, and the second support base is fixed on the base plate; the second stepper motor drives the gear to rotate;

[0018] The loading module includes a gear disk and an annular base. The gear disk is embedded in the annular base, and the annular base is fixed to the base plate. The first through groove is provided in the gear disk. The gear disk meshes with the gear.

[0019] Furthermore, the annular base is provided with multiple bearings in a centrally symmetrical manner, and the surface of each bearing is in rotational contact with the gear disk.

[0020] Furthermore, all of the bearings are fixed to the annular base by screws.

[0021] Furthermore, the second support base is in the shape of an "I".

[0022] Furthermore, it also includes a control module, which is electrically connected to the first stepper motor and the second stepper motor. The control module controls the operation of the first stepper motor and / or the second stepper motor according to the frequency signal of the received surface mount filter.

[0023] Compared with the prior art, the present invention has the following technical effects:

[0024] The fine-tuning device for a surface mount filter of the present invention automatically controls the reciprocating motion of the silver spray plate by the first stepper motor of the micro-motion module, thereby adjusting the position of the silver spray hole. Through the silver spray hole, silver plating can be deposited on the electrodes at different positions of the surface mount filter in the first through groove, so as to achieve the purpose of fine-tuning the frequency of the quartz crystal oscillator. This overcomes the drawback of the cumbersome operation of traditional manual control of evaporation fine-tuning position, greatly improves the efficiency of evaporation fine-tuning the frequency of surface mount filter, and thus improves the production efficiency of filter and reduces production cost.

[0025] For a dual-section surface mount filter, after the fine-tuning of one quartz crystal oscillator is completed, the fine-tuning device of the surface mount filter of the present invention further controls the gear disk to rotate 180° through the second stepper motor of the rotating module, so that the surface mount filter in the loading module flips its position to fine-tune the other quartz crystal oscillator. There is no need to break the vacuum to flip the filter position in the middle, so that the fine-tuning of two quartz crystal oscillators can be completed in one go, making the vapor deposition fine-tuning process of dual-section filter more convenient, improving the production efficiency of filter and reducing production costs. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the overall structure of a fine-tuning device for a surface-mount filter provided in an embodiment of the present invention;

[0028] Figure 2 for Figure 1 Top view of the loading module;

[0029] Figure 3 for Figure 1 Schematic diagram of the micro-motion module;

[0030] Figure 4 for Figure 1 Schematic diagram of the rotating module;

[0031] Figure 5 The diagram shows the program control logic of the control module provided in this embodiment of the invention.

[0032] The following are the labeling elements in the figure:

[0033] 1. Loading module, 2. Rotation module, 3. Micro-motion module, 4. Base plate, 5. Silver spray plate, 11. Gear disk, 12. Circular base, 13. Bearing, 14. Screw, 15. Positioning post, 21. Second stepper motor, 22. Second support base, 23. Gear, 31. First stepper motor, 32. First support base, 33. Disk, 34. Connecting rod, 35. Platform slider, 36. Fixing rod, 37. Slide rail. Detailed Implementation

[0034] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0035] In this invention, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0036] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0037] It should be understood that the terms "length", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0038] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0039] The terms "first" and "second" are used for descriptive purposes only, to distinguish objects, such as substances, from one another, and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. For example, without departing from the scope of embodiments of the invention, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0040] Please see Figures 1-5 The present invention will now describe a fine-tuning device for a surface-mount filter provided in an embodiment of the present invention.

[0041] In one embodiment of the present invention, a fine-tuning device for a surface mount filter includes a base plate 4, a loading module 1, a micro-motion module 3, and a silver spray plate 4. The loading module 1 is connected to the base plate 4. The loading module has a first through slot for loading a surface mount filter carrier. The micro-motion module 3 includes a first stepper motor 31, a first support base 32, a disk 33, a connecting rod 34, a platform slider 35, and a slide rail 37. The first stepper motor 31 is fixed on the first support base 32 and drives the disk 33 to rotate. The two ends of the connecting rod 34 are respectively connected to the disk 33 and the platform slider 35. The first support base 32 and the slide rail 37 are both fixed on the base plate 4. The platform slider 35 is slidably connected to the slide rail 37. The disk 33, the connecting rod 34, and the platform slider 35 form a crank-connecting rod mechanism. The silver spray plate 5 has silver spray holes. The silver spray plate 5 is connected to the platform slider 35 and is located directly below the first through slot of the loading module 1.

[0042] In use, the fine-tuning device for a surface-mount filter according to an embodiment of the present invention places the surface-mount filter into a surface-mount filter carrier, and then places the surface-mount filter carrier into the first through slot of the loading module 1. At this time, a silver plating layer can be deposited onto the electrodes of the surface-mount filter in the first through slot through the silver spraying holes on the silver spraying plate 5. Specifically, according to the position where the silver plating layer needs to be deposited on the electrodes of the surface-mount filter, the first stepper motor 31 of the micro-motion module 3 is controlled to operate, driving the platform slider 35 to slide along the slide rail 37, thereby driving the silver spraying plate 5 to reciprocate, achieving the purpose of adjusting the position of the silver spraying holes on the silver spraying plate 5.

[0043] The fine-tuning device of this invention achieves precise fine-tuning of different electrode positions through the micro-motion module 3, solving the problem of difficult fine-tuning of surface-mount filters. Driven by a first stepper motor 31, it achieves high-precision position control while possessing low-speed, high-torque characteristics and high durability. The circular motion of the disk 34 is converted into the reciprocating motion of the platform slider 35 via a crank-connecting rod mechanism. The movement of the platform slider 35 drives the silver spray plate 5, achieving precise displacement of the silver spray holes on the silver spray plate 5 and aligning them with the crystal oscillator electrodes. The silver spray plate 5 blocks excess vaporized silver after evaporation, allowing the vaporized silver to adhere to the electrodes through the designed silver spray holes.

[0044] The fine-tuning device for a surface mount filter according to an embodiment of the present invention automatically controls the reciprocating motion of the silver spray plate 5 through the first stepper motor 31 of the micro-motion module 3, thereby adjusting the position of the silver spray hole. Through the silver spray hole, silver plating can be deposited on the electrodes at different positions of the surface mount filter in the first through slot, thereby achieving the purpose of fine-tuning the frequency of the quartz crystal oscillator. This overcomes the drawback of the cumbersome operation of traditional manual control of evaporation fine-tuning position, greatly improves the efficiency of evaporation fine-tuning the frequency of the surface mount filter, and thus improves the production efficiency of the filter and reduces the production cost.

[0045] Furthermore, in this embodiment of the invention, a fixing rod 36 is connected to the platform slider 35; one end of the fixing rod 36 passes through a through hole provided on the base plate 4 and connects to the silver spray plate 5. For example... Figure 1 , Figure 3As shown, the upper end of the fixing rod 36 is connected to the platform slider 35, and the lower end passes through the through hole provided on the base plate 4 and connects to the silver spray plate 5. A second through slot is provided on the base plate 4 corresponding to the position of the first through slot, and the silver spray plate 5 is located directly below the second through slot. The through hole provided on the base plate 4 can be an oblong hole (waist-shaped hole). After the first stepper motor 31 starts, it drives the platform slider 35 to reciprocate along the slide rail 37, which in turn drives the silver spray plate 5 connected to the fixing rod 36 to reciprocate. Since the silver spray plate 5 is located directly below the first and second through slots, that is, the silver spray plate 5 located directly below the first and second through slots can be exposed. Through the silver spray holes on the silver spray plate 5, silver plating can be deposited on the electrodes at different positions of the surface mount filter in the first through slot, achieving the purpose of fine-tuning the quartz crystal oscillator frequency.

[0046] Furthermore, in this embodiment of the invention, the lower side of the base plate 4 is provided with two grooves (not shown in the figure), and the two sides of the silver spraying plate 5 are embedded in the grooves, and the silver spraying plate 5 is slidably connected to the grooves. By setting the grooves, the reciprocating motion of the silver spraying plate 5 can be guided, so that the movement path of the silver spraying plate 5 is smooth and precise.

[0047] Furthermore, in this embodiment of the invention, multiple silver spray holes are arrayed on the silver spray plate 5, allowing multiple surface mount filters to be mounted simultaneously within the surface mount filter carrier. The crystal oscillator frequencies of these multiple surface mount filters can be fine-tuned simultaneously through the multiple silver spray holes. Specifically, the multiple silver spray holes have equal diameters, and the silver spray plate 5 can be replaced according to the model of the surface mount filter.

[0048] Furthermore, in this embodiment of the invention, a positioning post 15 is provided in the first through groove. The positioning post 15 is used to fix and position the surface mount filter carrier. Figure 1 , Figure 2 As shown, two positioning stakes 15 are symmetrically arranged on both sides inside the first channel, which are used to fix and position the loading tray.

[0049] Furthermore, the first support base 32 of this embodiment is L-shaped, which includes an L-shaped vertical plate and a horizontal plate connected together. The vertical plate is connected to the first stepper motor 31, and the horizontal plate is connected to the base plate 4. The first stepper motor 31 is fixedly supported by the vertical plate of the L-shaped support base.

[0050] Furthermore, the fine-tuning device in this embodiment of the invention also includes a rotation module 2, which includes a second stepper motor 21, a second support base 22, and a gear 23; the second stepper motor 21 is fixed on the second support base 22, and the second support base 22 is fixed on the base plate 4; the second stepper motor 21 drives the gear 23 to rotate. The loading module 1 includes a gear disk 11 and an annular base 12, the gear disk 11 is embedded in the annular base 12, and the annular base 12 is fixed on the base plate 4; a first through groove is provided in the gear disk 11; the gear disk 11 meshes with the gear 23. Specifically, the second support base 22 is in the shape of an "I", such as... Figure 1 , Figure 4 As shown.

[0051] Thus, for a dual-section surface mount filter, after the fine-tuning of one quartz crystal oscillator is completed, the fine-tuning device of the surface mount filter in this embodiment of the invention also drives the gear 23 to rotate through the second stepper motor 21 of the rotation module 2, thereby driving the gear disk 11 meshing with the gear 23 to rotate. By controlling the gear disk 11 to rotate 180°, the surface mount filter in the loading module 1 located in the gear disk 11 is flipped to fine-tune the other quartz crystal oscillator. There is no need to manually flip the filter position by breaking the vacuum in the middle, so that the fine-tuning of the two quartz crystal oscillators can be completed in one go (that is, the frequency fine-tuning of the two crystal oscillators of the dual-section surface mount filter can be achieved by only one vacuuming operation), which makes the vapor deposition fine-tuning process of the dual-section filter more convenient, improves the production efficiency of the filter and reduces the production cost.

[0052] The fine-tuning device of this embodiment of the invention realizes automatic rotation of the surface-mount filter through the rotation module 2. This not only solves the problem of manual flipping, but also reduces the number of vacuuming operations, improving the stability and efficiency of the fine-tuning process. By using a second stepper motor 21 for driving, high-precision position control can be achieved, while also possessing low-speed, high-torque characteristics and high durability. Through the meshing of gear 23 with gear disk 11, low-speed, high-torque driving is achieved, while improving transmission efficiency, extending service life, and enabling fine-tuning of another crystal oscillator after automatic rotation, thus achieving efficient and precise fine-tuning of the two-section surface-mount filter.

[0053] Furthermore, in this embodiment of the invention, a plurality of bearings 13 are centrally symmetrically arranged on the annular base 12. Each bearing 13 can be fixed to the annular base 12 by screws 14, which can be hexagonal socket screws. The surface of each bearing 13 is in rotatable contact with the gear disk 11. Figure 1 , Figure 2 As shown, the outer side of the gear disk 11 is in contact with eight bearings 13. The bearings 13 are fixed to the ring base 12 by eight hexagon socket screws 14. The bearings 13 can assist the gear disk 11 to rotate and ensure the smooth rotation of the gear disk 11.

[0054] Furthermore, the fine-tuning device in this embodiment of the invention also includes a control module, which is electrically connected to the first stepper motor 31 and the second stepper motor 21. The control module controls the operation of the first stepper motor 31 and / or the second stepper motor 21 according to the received frequency signal of the surface-mount filter. Specifically, the control module can be a master control computer, and the program control logic diagram of the control module is as follows: Figure 5 As shown, the main control computer receives frequency data of the surface-mount filter collected by the measuring instrument, determines the position requiring fine-tuning during vapor deposition, and sends running commands to the micro-motion module 3 and / or rotation module 2 to control the operation of the first stepper motor 31 and / or the second stepper motor 21. This, in turn, controls the reciprocating motion of the silver spray plate 5 via the first stepper motor 31 and / or the rotation of the gear disk 11 via the second stepper motor 21. In this embodiment of the invention, the control module automatically controls the position of the fine-tuning electrode through program identification, thereby achieving fine-tuning of the surface-mount filter.

[0055] This invention also provides a method for fine-tuning a dual-section surface-mount filter using the above-described fine-tuning device, comprising the following steps:

[0056] The carrier disk carrying the surface mount filter is placed inside the first through slot of the loading module 1, and the carrier disk is positioned and fixed by two positioning posts 15. During the fine-tuning process, the vaporized silver formed by evaporation can be precisely attached to the electrodes of a single crystal oscillator in the surface mount filter through the silver spraying holes on the silver spraying plate 5.

[0057] The first stepper motor 31 drives the disk 33 to rotate, converting the circular motion into the reciprocating motion of the platform slider 35. The platform slider 35 drives the fixed rod 36 to reciprocate synchronously, thereby causing the silver spray plate 5 to produce a slight displacement. Since a single crystal oscillator of the surface mount filter has multiple electrodes, the frequency needs to be fine-tuned to the set value while reducing the frequency difference between the electrodes. The frequency difference and frequency of the crystal oscillator are monitored in real time by a network analyzer test device, and the position of the silver spray plate 5 is automatically adjusted by the control module based on the monitoring data, thereby realizing the automatic adjustment of the position of the fine-tuning electrodes and achieving the purpose of precise fine-tuning.

[0058] When the network analyzer test equipment detects that the crystal oscillator frequency has reached the set value, the second stepper motor 21 drives the gear 23 to rotate. The gear 23 meshes with the gear disk 11, causing the gear disk 11 to rotate. The bearing 13 assists the gear disk 11 in achieving smooth rotation, thereby causing the carrier disk carrying the surface-mount filter to rotate. After the carrier disk rotates 180°, the same fine-tuning operation can be performed on another crystal oscillator.

[0059] After the loading module 1 fixes and positions the carrier plate, the fine-tuning device of this invention performs precise fine-tuning on multiple electrodes on a single crystal oscillator in the surface mount filter within the carrier plate through the micro-motion module 3, and finally completes the one-time fine-tuning of the surface mount filter through the rotation module 2. This enables batch processing of surface mount filters and achieves efficient and high-precision fine-tuning of surface mount filters.

[0060] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A fine-tuning device for a surface-mount filter, characterized in that, include: Base plate; A loading module is connected to the base plate; the loading module is provided with a first through slot for loading a surface mount filter carrier disk. A micro-motion module includes a first stepper motor, a first support base, a disk, a connecting rod, a platform slider, and a slide rail; the first stepper motor is fixed on the first support base and drives the disk to rotate; the two ends of the connecting rod are respectively connected to the disk and the platform slider; the first support base and the slide rail are both fixed on the base plate; the platform slider is slidably connected to the slide rail; the disk, connecting rod, and platform slider form a crank-connecting rod mechanism; and... A silver spray plate is provided with silver spray holes; the silver spray plate is connected to the platform slider and is located directly below the first through slot.

2. The fine-tuning device for a surface-mount filter as described in claim 1, characterized in that, A fixing rod is connected to the platform slider; one end of the fixing rod passes through a through hole in the base plate and is connected to the silver spray plate; a second through groove is provided on the base plate at a position corresponding to the first through groove, and the silver spray plate is located directly below the second through groove.

3. The fine-tuning device for a surface-mount filter as described in claim 2, characterized in that, The bottom plate has two grooves on its lower side, and the silver spray plate is embedded in the grooves on both sides, and the silver spray plate is slidably connected to the grooves.

4. The fine-tuning device for a surface-mount filter as described in claim 1, characterized in that, The silver spraying holes are arranged in a plurality of arrays on the silver spraying plate; and / or the first through groove is provided with positioning posts, the positioning posts being used to fix and position the surface mount filter carrier.

5. The fine-tuning device for a surface-mount filter as described in claim 1, characterized in that, The first support base includes an L-shaped vertical plate and a horizontal plate, the vertical plate being connected to the first stepper motor, and the horizontal plate being connected to the base plate.

6. The fine-tuning device for a surface-mount filter as described in claim 2, characterized in that, The through hole is an oblong hole.

7. A fine-tuning device for a surface-mount filter as described in any one of claims 1-6, characterized in that, It also includes a rotation module, which comprises a second stepper motor, a second support base, and a gear; the second stepper motor is fixed on the second support base, and the second support base is fixed on the base plate; the second stepper motor drives the gear to rotate; The loading module includes a gear disk and an annular base. The gear disk is embedded in the annular base, and the annular base is fixed to the base plate. The first through groove is provided in the gear disk. The gear disk meshes with the gear.

8. The fine-tuning device for a surface-mount filter as described in claim 7, characterized in that, The circular base is provided with multiple bearings in a centrally symmetrical manner, and the surface of each bearing is in rotational contact with the gear disk.

9. The fine-tuning device for a surface-mount filter as described in claim 8, characterized in that, The bearings are all fixed to the annular base by screws; and / or the second support base is in the shape of an "I".

10. The fine-tuning device for a surface-mount filter as described in claim 7, characterized in that, It also includes a control module, which is electrically connected to the first stepper motor and the second stepper motor. The control module controls the operation of the first stepper motor and / or the second stepper motor according to the frequency signal of the received surface mount filter.

Images