WO2018143614A1

WO2018143614A1 - Cavity filter

Info

Publication number: WO2018143614A1
Application number: PCT/KR2018/001180
Authority: WO
Inventors: 김덕용; 장성호; 김정회; 조대일; 박남신
Original assignee: 주식회사 케이엠더블유
Priority date: 2017-01-31
Filing date: 2018-01-26
Publication date: 2018-08-09
Also published as: CN108448213A; CN108448213B

Abstract

The present invention provides a cavity filter having a slim and compact structure in which a push-pin type RF connector, which is formed such that a terminal is exposed to both sides or one side in a height direction, is embedded so as to reduce a size of an antenna system, rapidly perform a verification for an individual cavity filter while having high reproducibility, and enable the antenna system to be readily mounted.

Description

Cavity filter

The present invention relates to a cavity filter. More specifically, the present invention relates to a cavity filter for a massive MIMO antenna in which the connector fastening structure between the filter and the printed circuit board is improved in consideration of assembly and size.

The contents described in this section merely provide background information on the present embodiment and do not constitute a prior art.

Multiple Input Multiple Output (MIMO) technology is a technology that dramatically increases the data transmission capacity by using multiple antennas. The transmitter transmits different data through each transmit antenna, and the receiver transmits different data through appropriate signal processing. Spatial multiplexing technique to distinguish. Therefore, as the number of transmit / receive antennas is increased at the same time, the channel capacity increases to allow more data to be transmitted. For example, if you increase the number of antennas to 10, you get about 10 times the channel capacity using the same frequency band compared to the current single antenna system.

4G LTE-advanced uses up to 8 antennas. Currently, products with 64 or 128 antennas are being developed in the pre-5G phase, and base station equipment with a much larger number of antennas is expected to be used in 5G. This is called Massive MIMO technology. While current cell operation is 2-Dimension, 3D-Beamforming is possible when Massive MIMO technology is introduced, so Massive MIMO technology is also called FD-MIMO (Full Dimension).

In Massive MIMO technology, as the number of antenna elements increases, the number of transceivers and filters increases accordingly. In addition, as of 2014, more than 200,000 base stations are installed nationwide. That is, there is a need for a cavity filter structure that minimizes mounting space and is easy to mount, and requires an RF signal line connection structure to provide the same filter characteristics even after individually tuned cavity filters are mounted on an antenna.

The RF filter having a cavity structure has a resonator composed of a resonator rod which is a conductor inside a box structure formed of a metallic conductor, so that only an electromagnetic field having a natural frequency exists so that only a characteristic frequency of ultra high frequency passes by resonance. The bandpass filter of the cavity structure has a low insertion loss and is advantageous for high power, and thus is widely used as a filter of a mobile communication base station antenna.

The present invention has a main purpose to provide a cavity filter having a slimmer and more compact structure and the RF connector is built in the thickness direction in the body.

In addition, an object of the present invention is to provide an assembly method that can minimize the accumulation amount of the assembly tolerance occurring when assembling a plurality of filters and an RF signal connection structure that is easy to mount and maintains the frequency characteristics of the filter uniformly. have.

In order to solve the above problems, the cavity filter used in the base station antenna for mobile communication according to an embodiment of the present invention and installed on the outer member, the resonance element; A first case disposed on the outer member and including a resonance element therein; And a terminal portion electrically connected to the electrode pad of the outer member and the resonating element through the first case, wherein the terminal portion is electrically insulated from the first case, wherein the terminal portion is at least a portion of the first case from the bottom surface of the first case. Recessed terminal insertion hole; A pin member disposed inside the terminal insertion hole, the pin member including one end of which is connected to the resonating element and a terminal body portion extending from the other end of the pin portion and having a larger diameter than the pin portion; And an elastic conductor, disposed between the terminal body portion and the electrode pad between the terminal body portion and the electrode pad to electrically connect both sides, and when the cavity filter is installed on the outer member, the pin member and the electrode pad are compressed. And an elastic connector configured to provide contact pressure thereto.

The terminal insert may further include a dielectric bush inserted into the terminal insert, the terminal insert including: a third insert having a terminal gap and a constant air gap in the radial direction; A second insertion hole having a diameter smaller than the third insertion hole and into which a portion of the dielectric bush is inserted; And a first insertion hole having a smaller diameter than the second insertion hole and into which a portion of the dielectric bush is inserted.

In addition, the dielectric bush is in the form of a two-stage cylinder having a first end and a second end having a larger diameter than the first end, and a through hole penetrating the center of the rotation shaft is formed, and a pin part is inserted into the through hole from the second end side, so that the dielectric bush is formed. The pin member is fixed to.

In addition, the pin portion is characterized in that it comprises a wedge-shaped projection formed on the outer circumferential surface so that the pin portion does not fall in the opposite direction inserted into the dielectric bush.

In addition, the terminal body portion is formed shorter than the depth of the third insertion opening, the hollow portion having a cylindrical shape therein; And a cone-shaped opening having a diameter decreasing inward from the inlet.

In addition, the hollow portion is characterized in that it comprises a first annular groove formed on the inner peripheral surface of the hollow portion.

In addition, the elastic connector of the cavity filter, the cylindrical member is inserted into the hollow portion; A wedge-shaped annular protrusion protruding from the outer circumferential surface of the cylindrical member; A conical pin-socket contact portion extending from the cylindrical member and inserted into the opening; An impedance matching portion extending from the pinsocket contact portion; And at least one incision formed along the central axis of the elastic connector from an outer surface exposed to the outside after the elastic connector is inserted into the hollow portion, wherein the incision extends to a depth passing through the annular projection, and the annular projection is elastic. When the connector is inserted into the hollow portion is accommodated in the annular groove is characterized in that the size is formed to prevent the departure of the elastic connector.

In addition, the angle size from the central axis of the pin-socket contact portion is characterized in that formed 5 to 10 degrees larger than the angle size from the central axis of the opening.

In addition, the electrode corner formed by the outer surface of the elastic connector and the outer peripheral surface of the impedance matching unit is characterized in that it is formed in a round shape in the range of R0.1 to R0.5.

In addition, it characterized in that it further comprises a pin spring of the compression spring type inserted between the inner surface of the hollow portion and the elastic connector.

In addition, the elastic connector is formed from an elongated spring plate material having a predetermined width of most of the length except for the both ends, the finished form is a circular spring portion formed in a circular shape in the center; And two plate-like protrusions projecting perpendicularly to the circumference from two adjacent points on the circumference of the circular spring portion, wherein the width of the spring plate is smaller than the diameter of the hollow portion, and the diameter of the circular spring portion is larger than the diameter of the terminal body portion. It features.

In addition, the opening is characterized in that the circular spring portion is formed at an angle that can be circumscribed.

In addition, the solder is filled between the hollow portion and the plate-shaped protrusion inserted into the hollow portion, characterized in that the electrical connector and the pin member electrically and mechanically connected.

In addition, the cavity filter used in the base station antenna for mobile communication according to an embodiment of the present invention, the terminal insertion port of the elastic connector is formed from the bottom surface of the first case, the large diameter of the two-stage cylinder shape of the dielectric bush and A fourth insertion hole having a diameter of the same length and extending in parallel to the lower surface thereof; And a fifth insertion hole formed at a central position of one side of the fourth insertion hole and into which the first end of the dielectric bush is inserted.

In addition, the elastic connector is a pin insertion hole is formed so that the pin portion is inserted and supported by the terminal body portion; A first extension part extending in a direction perpendicular to the central axis of the pin part; And a second extension portion that is bent to have an obtuse angle from the first extension portion and extends to protrude outward from the bottom surface of the first case.

In addition, the terminal body portion is characterized in that the outer surface of the terminal body portion is formed to have a predetermined gap from the bottom surface of the first case in the state in which the elastic connector is inserted into the pin portion through the pin insertion hole and the pin member is assembled to the dielectric bush. .

In addition, the cavity filter used in the base station antenna for mobile communication according to an embodiment of the present invention further includes a star washer electrically connected to the first case, and the first case surrounds the third insertion opening. Further comprising a second annular groove, the second annular groove is characterized in that it is formed to accommodate the star washer and at least a portion of the star washer protrudes out the bottom surface of the first case.

In addition, the second annular groove is formed in an annular dovetail shape so that the diameter of the circumferential surface corresponding to the outer diameter increases in the depth direction, and the inlet outer diameter of the second annular groove is formed by retracting the star washer by elasticity. It is inserted into the bicyclic groove, characterized in that formed to a minimum diameter that can be prevented from leaving.

The second annular groove may further include a plurality of press-fit pin holes formed around the second annular groove; And a press-fit pin which is inserted into the press-fit pin hole and is inserted into the bottom surface of the first case and at least partially protrudes into the second annular groove to prevent the detachment of the star washer. .

In addition, the second annular groove includes a caulking hole formed around the second annular groove in proximity to the second annular groove, and has a circumferential surface corresponding to the outer diameter of the second annular groove by caulking after the star washer is inserted. The side wall of the recessed toward the central axis of the second annular groove is characterized in that configured to prevent the departure of the star washer.

The present invention can reduce the size of the antenna system by providing a cavity filter having a slim and compact structure in which the RF connector including the elastic connector in the thickness direction in the body, and can quickly and efficiently verify the verification of the individual cavity filter It can be carried out, it is possible to easily mount a plurality of cavity filters inside the mobile communication base station antenna.

1 is a diagram illustrating a laminated structure of an exemplary massive MIMO antenna.

2 is a cross-sectional view illustrating a state in which a cavity filter is stacked between an antenna board and a control board according to an embodiment of the present invention.

Figure 3 is a plan perspective view of the structure of the cavity filter according to an embodiment of the present invention as viewed from the bottom side.

4 is a cross-sectional view illustrating a terminal part structure of a cavity filter employing a push pin type elastic connector according to an exemplary embodiment of the present invention.

Figure 5 is a side cross-sectional view showing the terminal structure of the cavity filter employing a push pin type elastic connector according to an embodiment of the present invention.

6 is a partial cross-sectional view of a terminal portion structure of a cavity filter employing a push ring type elastic connector according to an embodiment of the present invention.

7 is a cross-sectional view showing an assembly process of a pin assembly employing a push ring type elastic connector according to an embodiment of the present invention.

8 is a plan view and a partial cross-sectional view showing a pin assembly employing a push ring type elastic connector according to an embodiment of the present invention.

9 is a conceptual diagram illustrating a manufacturing method of an elastic connector of a push ring method according to an embodiment of the present invention.

10 is an analytical model of a terminal portion of a general plunger method for comparison.

11 is an electric field analysis result of the terminal portion of the general plunger system of FIG. 10.

12 is an analysis model of a terminal unit employing a push pin type elastic connector according to an exemplary embodiment of the present invention.

13 is an electric field analysis result of the terminal unit employing the push pin type elastic connector according to an embodiment of the present invention.

14 is an analysis model of a terminal unit employing a push ring type elastic connector according to an exemplary embodiment of the present invention.

15 is an electric field analysis result of a terminal unit employing an elastic connector of a push ring method according to an embodiment of the present invention.

FIG. 16 is a graph illustrating comparison results of insertion loss analysis of the contact RF terminal units disclosed in FIGS. 10, 12, and 14.

FIG. 17 is a graph illustrating comparison of reflection loss analysis results of the contact RF terminal units disclosed in FIGS. 10, 12, and 14.

18 is a conceptual diagram illustrating a terminal part structure of a cavity filter employing a leaf spring type elastic connector according to an embodiment of the present invention.

19 is a cross-sectional view illustrating a state in which a cavity filter is attached to a socket of a rear surface of an antenna board according to an embodiment of the present invention.

20 is a cross-sectional view illustrating a state in which a cavity filter is attached to a rear surface of an antenna board according to an embodiment of the present invention.

21 is a plan view illustrating a test board of a cavity filter according to an exemplary embodiment of the present invention.

22 is a cross-sectional view illustrating a test board of a cavity filter according to an exemplary embodiment of the present invention.

FIG. 23 is a plan view illustrating a test board of a cavity filter according to an exemplary embodiment of the present invention, in which a star washer disposed around an elastic connector is omitted.

FIG. 24 is a cross-sectional view of FIG. 23 illustrating a test board of a cavity filter according to an embodiment of the present disclosure. FIG.

FIG. 25 is a plan view illustrating a test board of a cavity filter including a leaf spring type elastic connector according to an exemplary embodiment of the present invention. FIG.

FIG. 26 is a cross-sectional view of FIG. 25 illustrating a test board of a cavity filter employing a leaf spring type elastic connector according to an embodiment of the present invention.

27 is a conceptual diagram illustrating a star washer according to an embodiment of the present invention.

FIG. 28 is a conceptual view illustrating a process of forming a second annular groove having a dovetail shape accommodating a star washer according to an embodiment of the present invention.

FIG. 29 is a conceptual view illustrating a second annular recess accommodating a star washer and a press-fit pin for preventing separation of the star washer according to an embodiment of the present invention.

30 is a conceptual view illustrating a caulking process for preventing the separation of the second annular groove and the star washer containing the star washer according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail through exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. Throughout the specification, when a part is said to include, 'include' a certain component, which means that it may further include other components, except to exclude other components unless otherwise stated. . In addition, terms such as '?', 'Module' described in the specification means a unit for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software.

1 is a perspective view showing an exemplary appearance of an antenna device 10 in which an antenna assembly according to the present invention is incorporated. The antenna device 10 includes a housing in which a heat sink 110 is formed, and a radome 170 coupled to the housing. An antenna assembly is embedded between the housing and the radome 170. A power supply unit (PSU) 120 is coupled to the bottom of the housing, for example, via a docking structure, and the power supply unit 120 is an operating power source for operating electronic components provided in the antenna assembly. To provide.

In general, the antenna assembly has a cavity filter (cavity filter, 18) is arranged on the back of the antenna board 150 in which a plurality of antennas 160 are arranged on the front, the number of antennas 160, the associated PCB board 130 is followed It has a laminated structure. The cavity filter 140 is tuned and verified in detail so as to have frequency characteristics that meet the specifications individually before mounting. It is desirable that the tuning and verification process be done quickly in an environment with the same characteristics as the mounted state.

Referring to FIG. 2, the conventional RF connector 142 is excluded, thereby facilitating the connection and providing an antenna structure 11 having a lower height profile. In addition, the RF connection is provided on both sides of the height direction, by connecting the elastic connector (240, 340, 440), even if vibration and thermal deformation occurs in the antenna board 150 or PCB board 130, RF connection is maintained the same. There is an advantage that there is no change in frequency characteristics.

Example 1

3 and 4, the internal structure including the resonant element is omitted.

3 and 4, the cavity filter 18 according to an embodiment of the present invention includes a first case 180 and a first case 180 including a resonance element (not shown) and having a hollow inside. The terminal part 20 provided in the height direction of the cavity filter 18 and the assembly holes 182 provided on both sides of the terminal part 20 are disposed on both sides of the second case 181 and the first case 180 in the longitudinal direction. Include. The terminal unit 20 penetrates through the first case 180 to electrically connect the electrode pad of the external member, for example, the PCB board 130 or the antenna board 150, to the resonance element.

Both assembling parts 184 including the terminal part 20 of the first case 180 and the second case 181 may have a structure formed thicker than the bottom surface 186 which is an area therebetween depending on the application. have. For example, when the lower surface 186 of the first case 180 is assembled to the PCB board 130 on which various elements are mounted, both assembly units 184 may interfere with the element on which the first case 180 is mounted. It can have a thickness that can be avoided. As illustrated in FIG. 4, the external terminal of the terminal unit 20 may be formed such that one side thereof faces the lower surface 188 of the first case 180 and the other side thereof protrudes from the assembly reference surface of the second case 181. According to the mounting form of the cavity filter 18, the external terminal of the terminal unit 20 may be formed to be exposed to the lower surface 188 of the first case 180 in the same direction.

The terminal portion 20 of the cavity filter 18 according to the exemplary embodiment of the present invention may include a terminal insertion hole 210, a dielectric bush 220, a pin member 230, an elastic connector 240, and a pin spring 250. ) And star washer (260).

The terminal insertion hole 210 has a cylindrical shape and is formed from the bottom surface 188 of the first case 180 to pass through the first case 180, or is formed from the top surface of the first case 180. It may be provided through one case 180. When the terminal insertion hole 210 is formed from the top surface of the first case 180, a through hole is formed in the second case 181, and the depth of the terminal insertion hole 210 may be adjusted in consideration of this. The terminal insertion hole 210 is formed in three stages to decrease the diameter in stages. The portion having the smallest diameter in the terminal insertion hole 210 is defined as the first insertion hole 212, the portion having the next diameter is the second insertion hole 214, and the portion having the largest diameter is the third insertion hole 216. do.

Dielectric bush 220 is in the form of a two-stage cylinder. The dielectric bush 220 has a through hole 226 penetrating the center of the rotation shaft. The dielectric bush 220 is inserted into and fixed to the first insertion hole 212 and the second insertion hole 214. The dielectric bush 220 may be made of Teflon material. In one embodiment, one body is configured in the form of a two-stage cylinder, but is not limited thereto, and may be assembled to have a two-stage cylinder form with different diameters.

The pin member 230 is in the form of a two-stage cylinder in which the pin portion 232 and the terminal body portion 234 are integrally formed in the longitudinal direction. In one embodiment, the socket body 236 is formed in the terminal body 234. The fin member 230 may be gold plated on a BeCu (Beryllium Copper) material. The pin portion 232 is inserted into and fixed to the through hole 226 of the dielectric bush 220. The outer circumferential surface of the pin portion 232 is formed with a wedge-shaped protrusion 235 so that the pin portion 232 does not fall in the opposite direction in which the pin portion 232 is inserted. The annular stepped portion formed at the boundary between the pin portion 232 and the terminal body portion 234 is assembled to abut one side of the dielectric bush 220. The terminal body part 234 is formed to be shorter than the depth of the third insertion hole 216, and a hollow socket part 236 is formed therein. The terminal body portion 234 is formed with a cone-shaped opening 238 that decreases in diameter from the inlet. In one embodiment of the present invention, the inner wall of the terminal body portion 234 in the region where the cone-shaped opening 238 is formed is inclined at an angle of 30 degrees with respect to the central axis, for example. The first annular groove 237 is formed inside the opening 238 having a cone shape, and the separation of the elastic connector 240 inserted therein can be prevented. A spring 250 may be inserted between the innermost inner surface of the opening 238 and the tip of the insertion portion of the elastic connector 240 to further provide a force for pushing the elastic connector 240 out of the opening 238. .

The elastic connector 240 extends from the pinned contact portion 244 and the pinned socket contact portion 244 of the cylindrical structure inserted into the socket portion 236, the truncated cone shape inserted corresponding to the opening 238 of the cone shape. An impedance matching portion 246 is integrally formed in the longitudinal direction. The elastic connector 240 may be gold plated on the BeCu material. In the middle of the longitudinal direction of the cylindrical structure is formed a wedge-shaped annular projection 242 protruding from the outer peripheral surface. The annular protrusion 242 is accommodated in the first annular groove 237 when the elastic connector 240 is inserted into the socket 236 to prevent the elastic connector 240 from being separated from the socket 236.

The angle of the pin socket contact portion 244 is formed 5 degrees to 10 degrees larger than the angle of the cone-shaped opening portion 238 of the socket portion 236 with respect to the central axis. In addition, the elastic connector 240, the elastic connector 240 is inserted into the socket portion 236, the cross-shaped cut portion 248 is formed locally along the central axis from the outer surface exposed to the outside. The depth of the incision 248 extends through the truncated cone shape to the cylindrical structure of the elastic connector 240. In one embodiment, the cutout 248 is illustrated as a cross shape, but is not limited thereto. The cutout 248 may have a straight shape or a plurality of slots.

The elastic connector 240 touches the cone-shaped opening 238 of the socket 236 in a state where the elastic connector 240 is inserted into the socket 236 so that the cross-shaped cutout 248 is not retracted. Protrudes from the bottom surface 188 of the first case 180, and has a length in which the elastic connector 240 is inserted while pressing the opening 238 of the socket portion 236 when the cavity filter 18 is mounted. Can be.

The outer edge of the outer surface of the elastic connector 240 is an area electrically connected to the electrode pad formed on the PCB board 130 to which the cavity filter 18 is assembled while the elastic connector 240 is retracted. This outer edge is defined by the electrode edge 249. In one embodiment, the electrode corner 249 is formed in a round shape in the range of R0.1 to R0.5, even if the elastic connector 240 is retracted to form a shallow cone shape in which the outer surface is concave in the plane. 249 is provided to have a uniform contact area with the electrode pad formed on the PCB board 130. The cavity filter 18 is actually assembled with the PCB board 130 and may have various height deviations. Even if the elastic connector 240 is retracted by forming the electrode edges 249 in a round shape, the cavity filter 18 may be uniform. It can have one contact area.

The angle of the opening 238, the angle of the pin socket contact 244, the length of the elastic connector 240 and the round size of the electrode edge 249 may be defined by one side or the second case 181 of the first case 180. It is preferable to select based on when the assembly reference plane and the PCB board 130 are combined. In more detail, when the PCB board 130 is coupled, the elastic connector 240 is pushed up and slides along the opening 238 of the socket 236, and the cross-shaped cutout 248 is lifted up. When the cutout 248 is retracted, the angle of the pin socket contact portion 244 of the elastic connector 240 decreases, and the contact area between the opening 238 and the pin socket contact portion 244 changes. In addition, as the outer surface of the elastic connector 240 is retracted in the form of a shallow cone, the area where the electrode edge 249 contacts the electrode pad of the PCB board 130 is also changed. In addition, the spring 250 inserted into the socket 236 pushes the elastic connector 240 toward the PCB board 130 and the force including the reaction force from the pin socket contact 244 acts on each contact. Each contact surface is elastically deformed.

Design specifications of the socket portion 236, the elastic connector 240 and the spring 250 to determine the contact area is preferably selected in consideration of the impedance of the terminal portion (20). That is, it is preferable to determine the design specification that the change of the impedance along the signal path of the terminal portion 20 including the contact resistance determined by the contact area and the contact pressure is minimized. In particular, in the case of a mobile communication antenna signal in which a high frequency is transmitted, the signal quality may be deteriorated if the characteristic impedance of the signal line is not constant. Impedance mismatching of the signal path in multi-gigahertz signals can increase the voltage standing wave ratio (VSWR), which can degrade signal quality due to signal reflection and distortion.

Consideration for maintaining the impedance of the terminal unit 20 uniformly is also necessary in selecting the size of the first insertion hole 212 to the third insertion hole 216 and the size of the terminal body portion 234. The third insertion hole 216 is spaced apart from the outer circumferential surface of the terminal body portion 234 with a predetermined air gap, and between the first and second insertion holes 212 and 214 and the pin portion 232, for example, Teflon. The dielectric bush 220 of the material is mediated. The pin part 232 and the terminal body part 234 of the pin member 230 have a stepped diameter, and the diameter and the depth of the second insertion hole 214 are considered in this regard, the pin member 230 and the terminal insertion hole 210. It is preferable to select so that the impedance of the liver remains constant.

The dielectric constant of the Teflon material is about twice that of air. In consideration of this, the diameter of the third insertion hole 216 is larger than that of the first and second insertion holes 212 and 214. For example, instead of Teflon, if the dielectric bush 220 is made of PEEK material having a dielectric constant about three times that of air, the diameter of the third insertion hole 216 is larger than that of Teflon.

5A to 5D illustrate the shapes of the electrode corners 249 and the impedance matching unit 246 of the elastic connector 240 in contact with the electrode pads of the PCB board 130 in various forms. These shapes and sizes can be selected by performing numerical analysis in consideration of the distance from the third insertion opening 216 or by evaluating the VSWR of the terminal unit 20 using, for example, a network analyzer.

5A illustrates an example in which the impedance matching part 246 protrudes vertically at a position away from the pin socket contact part 244, and the electrode edge 249 is an example in which a fine round of R0.1 is formed. 5B is an example in which the inclination angle of the pin socket contact portion 244 of the elastic connector 240 is maintained and extends to the electrode edge 249. 5C illustrates a case in which the impedance matching unit 246 is formed to have an inclined surface in which the diameter decreases again in a position deviating from the pin socket contact portion 244. FIG. 5D illustrates an example in which a diameter of the electrode edge 249 is relatively large rounded to R0.5, having an inclined surface that decreases again in diameter at a position away from the pin socket contact portion 244. 5E illustrates a case in which the spring 250 is omitted, a force (contact pressure) for pushing the electrode pad of the elastic connector 240 and the PCB board 130 in contact with the elastic connector 240 is cross-cut in the elastic connector 240. It is an example showing the case where the part 248 is formed by the reaction force from the pin-socket contact part 244 as it retracts.

A second annular groove 270 may be formed outside the third insertion hole 216 to receive the star washer 260 that surrounds the signal line, surrounds the cylindrical portion, and is inserted to secure the ground connection.

Example 2

Figure 6 is a partial cross-sectional view of the terminal structure of the cavity filter employing a push ring type elastic connector according to an embodiment of the present invention.

Referring to FIG. 6, the terminal unit 20 according to another embodiment of the present invention includes a terminal insertion hole 210, a dielectric bush 320, a pin member 330, a push ring type elastic connector 340, and a star washer ( 260). In the embodiment of FIG. 6, the impedance matching is more strictly performed. The dielectric bush 220 is formed in a separate type, and the diameter of the through hole 226 of the dielectric bush 320 in two stages is different from each other. Although the pin portion 332 of the 330 is formed in two stages corresponding to the dielectric bush 320, the terminal insertion hole 210, the dielectric bush 320, the pin portion 332 and the star washer 260 are described above. It may be configured in the same form as the embodiment of FIG.

The pin member 330 according to an embodiment includes a terminal body portion 334 having a pin portion 332 and a socket portion 336. The pin member 330 may be gold plated on the BeCu material. The pin portion 332 is inserted into and fixed to the through hole 226 of the dielectric bush 320. On the outer circumferential surface of the fin part 332, a wedge-shaped protrusion 235 is formed so that the pin member 330 does not fall in the opposite direction in which the pin member 330 is inserted. The annular stepped portion formed at the boundary between the pin portion 332 and the terminal body portion 334 is assembled to abut one side of the dielectric bush 320. The terminal body portion 334 is formed shorter than the depth of the third insertion hole 216, the inside is hollow, and a cone-shaped opening 338 is formed to decrease in diameter from the inlet to the inside. In one embodiment of the present invention, the cone-shaped opening 338 is formed to be inclined at an angle of 60 degrees with respect to the central axis, for example, so that the circular spring portion 344 of the elastic connector 340 of the push ring type is circumscribed. Is formed.

Elastic connector 340 of the push ring method according to an embodiment is formed from a spring plate having a predetermined width of most of the length except for both ends. The elastic connector 340 includes a circular spring portion 344 and two plate-like protrusions 342 projecting perpendicularly to the circumference from two points 346 adjacent to the circumference of the circular spring portion 344 on one side. The width of the elastic connector 340 is formed so that the plate-like protrusion 342 can be inserted into the socket 336. The elastic connector 340 may be formed of a BeCu material and may be gold plated, and the two plate-shaped protrusions 342 may be spaced apart from each other, and the circular spring part 344 may be deformed into an ellipse when an external force acts in the center direction thereof. It is formed to act as a leaf spring.

That is, when the two plate-like protrusions 342 of the elastic connector 340 are inserted into the socket portion 336, the two plate-like protrusions 342 are opened to each other so that the end portions of the two plate-like protrusions 342 are in close contact with the inner circumferential surface of the socket portion 336 to maintain the inserted state. Can be. In addition, the circular spring portion 344 is in close contact with the cone-shaped opening 338, the position opposite the plate-shaped protrusion 342 protrudes by a predetermined distance from the bottom surface 188 of the first case 180. When the cavity filter 18 is mounted, the electrode pad is elastically deformed in an ellipse shape as the electrode pad presses the circular spring part 344, and the pin member 330 and the electrode pad are electrically connected to each other, even when external vibration is applied. It serves to provide sufficient contact pressure to press the contact site so that there is no change.

Referring to FIGS. 7 and 8, the push ring type elastic connector 340 is inserted into the socket 336, and the two plate-shaped protrusions 342 inserted into the cylindrical holes inside the socket 336 are soldered. It is preferred to be connected by soldering and joined to the pin assembly 32. Preferred embodiments of assembling the elastic connector 340 and the pin member 330 according to an embodiment are as follows.

After a certain amount of solder is inserted into the socket portion 336 with the plurality of pin members 330 prepared so that the openings 338 of the socket portion 336 of the pin member 330 are upward, the solder may melt. After the fin member 330 is heated, the elastic connector 340 is inserted. The elastic connector 340 inserted into the socket 336 is held until the solder cools and hardens. When the solder is hardened, the coupling between the elastic connector 340 and the pin member 330 is completed. Cavity filter 18 handles high frequency signals at the Giga Hertz level, and in delivering signals in these frequency bands, it is desirable to minimize the portion where mechanical contact may be incomplete.

The mobile communication base station antenna in which the cavity filter 18 is used is important to ensure extremely low noise characteristics in the operating frequency band. Accordingly, there is a need to minimize passive intermodulation distortion (PIMD) caused by not only mechanical connection parts of various RF connection elements, but also metal contact parts and inside dissimilar metal coated parts. In particular, a radio frequency signal having high frequency and high energy may cause an intermediate frequency by mixing between multiple frequencies by nonlinearity of voltage and current at these contacts or the like. The signal quality of the antenna may be greatly degraded by the intermediate frequency which is close to the frequency of the main signal among the induced intermediate frequencies. This PIMD can be minimized by reliably joining the plate-like protrusions 342 inserted into the socket portion 336 by soldering.

The pin assembly 32 employing the push ring type elastic connector according to an embodiment of the present invention is electrically and physically connected by soldering as described above, and the cavity filter 18 is installed in the form of a circular leaf spring. It is characterized in that it is connected to the electrode pad of the PCB substrate. In particular, the circular spring portion 344 provides a stable mechanical connection with the electrode pad, and because the impedance fluctuations of the signal line is small, the signal reflection performance is implemented in a simple component structure.

Referring to FIG. 9, the elastic connector 340 according to an embodiment may be press sheet metal formed from a spring plate and undergo heat treatment to form a state in which a plurality of elastic connectors 340 are easily bent and separated while one side is attached. Can be made. Since the circular spring portion 344 is in contact with the opening 338 of the socket portion 336 and the electrode pad, fine blanking is performed so that the burrs of the corner portion can be generated only inside the circular portion by fine blanking. It is desirable to.

The diameter of the circular spring portion 344 is selected based on the outer diameter of the terminal body portion 334. The circular spring portion 344 has two points in close contact with the cone-shaped opening 338 of the socket portion 336, and is spaced apart from the inner circumferential surface of the third insertion hole 216 to have a predetermined characteristic impedance. This impedance value preferably forms the diameter of the circular spring portion 344 so as to be equal to or similar to the characteristic impedance between the outer diameter of the terminal body portion 334 and the third insertion opening 216. Impedance mismatching of the signal path in a signal of several hertz level may increase the voltage standing wave ratio so that the signal quality may be degraded due to signal reflection and distortion, so the change in impedance is preferably minimized.

The circular spring portion 344 has a circular one side in contact with the electrode pad and is divided into two parts and electrically connected to the opening 338 of the socket portion 336, but the circular spring portion 344 has a diameter of 1 compared to the width. Since it may be determined at a level of about -2 times, when viewed from the inner circumferential surface of the third insertion hole 216 corresponding to the ground electrode, it may be seen that one cylindrical electrode is electrically extended. That is, in the high frequency signal band transmitted from the cavity filter 18 as in the present invention, even if the shape of the circular spring portion 344 is connected to the socket portion 336, the variation in impedance may be small.

10 to 17 compare the RF characteristics of the various types of contact RF terminal unit 20 and the shape of the electric field through computer simulation. The right side of the analytical model is the terminal portion 20, and the left side is a cylindrical terminal corresponding to the electrode pad, and surrounds the cylindrical ground terminal.

Referring to FIG. 11, it can be seen that a terminal section of a conventional plunger structure shown in the middle of the electric field distribution appears due to structural limitations. The pin portion supported by the spring has a considerably smaller diameter than the pin housing accommodating the pin, and there is a section in which the gap is rapidly separated from the inner circumferential surface of the cylindrical ground end. As a result, the terminal portion of the general plunger structure has a smaller diameter of the protruding pin portion than the outer diameter of the plunger body, resulting in a sudden change in impedance, and thus has a high insertion loss (S21) value and a reflection loss (S11) value.

The analysis shows that the insertion loss is -0.006dB and the return loss is -28dB at 4 GHz. This can be interpreted as a large reflection of the signal due to the impedance fluctuation region in the middle of the signal path.

Referring to FIG. 13, in the case of the terminal unit 20 using the push pin type elastic connector according to the exemplary embodiment of the present invention, it can be seen that the distribution of the electric field is relatively uniform. The push pin type elastic connector can maintain the spacing of the impedance discontinuous section relatively narrow, for example, 0.5 mm or less, and be similar to the outer diameter of the terminal body portion 234 based on the inner circumferential surface of the third insertion hole 216. It is advantageous to minimize the variation of impedance. Analysis results show that the insertion loss is -0.0003dB and the return loss is -41dB at 4 GHz.

Referring to FIG. 15, even in the terminal part 30 employing the push ring type elastic connector according to the exemplary embodiment, the pin assembly 32 may have a relatively uniform electric field with the inner circumferential surface of the third insertion hole 216. It can be seen forming. Although the shape of the electric field is different from the inside of the circular spring portion 344, the distribution of the electric field is formed outside the circular spring portion 344, the change of the electric field is continuously made with respect to the inner peripheral surface of the third insertion hole 216 You can see that. That is, since there is no section in which the impedance of the signal line is changed discontinuously, there is an advantage that the insertion loss and the return loss can be kept low. On the other hand, the circular spring portion 344 has a simple structure while ensuring sufficient contact pressure, it can be deformed in various sizes can be easily impedance matching. Analysis results show that the insertion loss is -0.003dB and the return loss is -31dB at 4 GHz.

16 and 17, the insertion loss and the reflection loss of the three types of terminal parts described above can be compared, and the terminal part 20 having the push pin structure has the best signal quality and the terminal part 30 having the push ring structure. ) Also showed sufficient performance for practical use.

In the above comparison, the influence of PIMD generation due to incomplete internal contact between the pin portion of the general plunger type and the pin housing is not considered in the analysis, and in consideration of this, the general plunger structure may further degrade the signal transmission quality. have. On the other hand, the terminal portion 20 having the push pin structure is firmly contacted by elasticity with both contact portions having an annular contact surface by the elastic connector 240, and the terminal portion 30 having the push ring structure is the socket portion 336. Is directly bonded by soldering, and the PCB board 130 can secure a stable contact by the elastic spring portion 344 of the circular spring part 344, so that even if external vibration is applied, the signal quality can be maintained uniformly without increasing PIMD. have.

Example 3

FIG. 18A illustrates a pin member structure and a leaf spring inserted into the terminal insertion hole 410 of the cavity filter 18, and FIG. 18B is a plan view illustrating the leaf spring contact portion, and FIG. 18C. ) Is a side view showing the leaf spring contact.

Referring to FIG. 18, the leaf spring type terminal portion 40 according to another embodiment of the present invention may include a terminal insertion hole 410, a dielectric bush 420, a pin member 430, and a leaf spring type elastic connector 440. It includes.

In one embodiment, the terminal insertion hole 410 includes a fourth insertion hole 412 and a fourth insertion hole having an elongated cross section extending from the bottom surface of the first case 180 to accommodate the leaf spring type elastic connector 440. 412 includes a fifth insertion hole 414 in the form of a cylindrical hole formed at one central position of the long hole shape. The fourth insertion hole 412 is a region shown as a rectangle in Fig. 18 (c).

The dielectric bush 420 is in the form of a two-stage cylinder and has a through hole penetrating the center of the rotating shaft. The first end of the dielectric bush 420 is formed to have a diameter that is inserted into the fifth insertion hole 414, and the second end having a diameter larger than the first end of the dielectric bush 420 is the fourth insertion hole 412. At least a portion of one side of the diameter is formed. The height of the second end of the dielectric bush 420 is a predetermined gap from one side or the ground electrode surface of the PCB board 130 to which the cavity filter 18 is coupled after the elastic connector 440 and the pin member 430 are assembled. It is set to a height having a constant impedance as a whole. The dielectric bush 420 may be made of Teflon material. The outer diameter of the first end of the dielectric bush 420 and the size of the through hole are determined in consideration of the dielectric constant of the dielectric bush 420 so that the terminal portion 40 has a predetermined characteristic impedance.

The pin member 430 penetrates the elastic connector 440 and is inserted into the dielectric bush 420 to fix the pin 432 and the low height head that closely contacts the elastic connector 440 to the dielectric bush 420. portion 434. The outer circumferential surface of the pin portion 432 includes a wedge-shaped protrusion 435 formed so as not to fall out in the opposite direction in which the pin member 430 is inserted. The pin member 430 may be gold plated on the BeCu material.

The leaf spring type elastic connector 440 according to an embodiment extends from one side of the annular portion 444 and the annular portion 444 having a through hole 442 at the center thereof and having a narrower width than the annular portion 444. The first extension part 446 and the first extension part 446 are bent to have an obtuse angle (eg, 120 degrees to 130 degrees) so that the elastic connector 440 protrudes out of the bottom surface 188 of the first case 180. A second extension portion 448 and a bend portion 449 between the first extension portion 446 and the second extension portion 448. The tip of the second extension portion 448 is formed to press the electrode pad of the PCB board 130 formed to contact the same, and to maintain a predetermined contact area.

Both sides of the bent portion 449 may have notches formed so that the bending operation may be performed with a uniform position and angle. The leaf spring type elastic connector 440 based on the bent portion 449 may be bent to provide an elastic force in the bent direction. The through hole 442 is formed to have a size that can penetrate only the pin portion 432 of the pin member 430. The annular portion 444 is in close contact between the head 434 and the second end of the dielectric bush 420 when the elastic connector 440 is assembled to the dielectric bush 420, the elastic connector 440 and the pin member 430 Is arranged to be electrically connected. A conductive paste may be applied between the elastic connector 440 and the pin member 430 or may be more firmly connected by soldering.

The electrode pad of the PCB board 130 to which the leaf spring terminal portion 40 is electrically connected may have a circular electrode pad contacting the tip of the second extension portion 448. In addition, the impedance variation may be minimized by disposing a plurality of plated thru vias that penetrate the circular electrode pads through the PCB board 130 at an appropriate gap and pitch.

19 and 20, the cavity filter 18 according to the exemplary embodiment of the present invention may be coupled to the socket 152 attached to the antenna board 150 as shown in FIG. 19, and As shown in FIG. 1, the electrode pad may be coupled to the electrode pad formed on the antenna board 150. The cavity filter 18 according to the exemplary embodiment of the present invention is connected to the antenna board 150 and the PCB board 130 with a predetermined contact pressure by the

elastic connectors

240, 340, and 440, regardless of the assembly tolerance. It is possible to provide RF signal line connection with constant quality.

Cavity filter 18 is used in the base station antenna device 10 as many as is mounted for each individual antenna (160). Tuning and verifying these cavity filters 18 precisely and quickly can be said to be an important factor for improving the quality and cost reduction of the base station antenna device 10.

The cavity filter 18 including the

terminal units

20, 30, and 40 of the

elastic connectors

240, 340, and 440 according to an embodiment of the present invention provides a highly reproducible RF signal line connection. No coupling screw or snap lock member is required on the RF connector, and the electrode pad and the RF connector of the PCB to be assembled 130 are closely attached to each other by elasticity of the

elastic connectors

240, 340, and 440. It is characterized by being removable.

The following is a description of the verification of the cavity filter 18, which takes the case where the

terminal portions

20, 30, 40 of the cavity filter 18 are arranged in the same direction. Even when the arrangement direction of the

terminal parts

20, 30, 40 is reversed, the connection of the RF signal line can be made quickly and easily. 21 to 24 are examples of the case of the cavity filter 18 employing the push pin type and the push ring type

elastic connectors

240 and 340, and FIGS. 25 and 26 are the leaf spring type elastic connectors ( An example is the case of the cavity filter 18 in which 440 is employed.

21 and 22 conceptually show a state in which four cavity filters 18 are mounted on the cavity filter 18 test board 50, and SMA type RF connectors 510 are mounted on left and right sides. do. The cavity filter 18 test board 50 is provided with a circular electrode pad in electrical contact with the

elastic connectors

240 and 340, and tests the through-conducting vias to avoid contact with the

elastic connectors

240 and 340 of the circular electrode pad. It is connected to the back of the board 50 is connected to the central terminal of the SMA RF connector 510. A device such as a network analyzer is connected to the SMA RF connector 510 so that the plurality of cavity filters 18 can be quickly verified.

23 and 24, the second annular groove 270 surrounding the outside of the third insertion hole 216 and the star washer 260 accommodated therein are omitted, and the left and right lengths of the cavity filter 18 are omitted. The configuration can be reduced more. The shape of the terminal unit 20 may be variously modified as shown in FIG. 5.

25 and 26, the cavity filter 18 having the leaf spring type terminal part according to an embodiment may reduce the overall outer diameter of the terminal part 40 to be smaller than the embodiment shown in FIG. 22 or 24. It can be formed is advantageous in the case of reducing the left and right length.

The cavity filter 18 test board 54 is basically a form in which the ground electrode surface is wide on both sides. In addition, by placing a plurality of through-conducting vias that pass through the test board 54 at a proper gap and pitch, surrounding the circular pad to which the center terminal of the SMA RF connector 510 and the elastic connector 440 are connected, the impedance variation can be minimized. Can be.

The following describes the configuration for preventing the departure of the annular groove and the star washer that accommodates the star washer.

The first case 180 of the cavity filter 18 is hollow and has a complicated internal shape including a resonance element (not shown). The first case 180 is usually formed by pressing a material including aluminum or magnesium alloy.

Referring to FIG. 28, the second annular groove 270 of the first case 180 formed in a shape having a vertical wall is processed by a dovetail machining tool 910 so that the diameter of the inner edge thereof is increased. The washer 260 receiving portion is formed. The inlet of the dovetail-shaped second annular groove 270 is formed to the minimum diameter that the star washer 260 can be retracted and inserted by elasticity.

Referring to FIG. 29, a plurality of holes in which the press-fit pin 920 is inserted are formed outside the second annular groove 270 ′ and press-fit 3 or more press-fit pins 920 having a thin head formed therein to form a star washer ( 260 is a configuration for preventing the departure.

Referring to FIG. 30, a plurality of holes are formed outside the second annular groove 270 ″ and the side wall 930 of the second annular groove 270 ″ is recessed toward the star washer 260 by caulking. It is a structure which prevents the departure of 260. FIG. The surface may rise locally by caulking. Therefore, the upper surface of the caulking hole 940 is formed to form a high reference plane coupled to the PCB board 130 or the height of the sidewall 930 of the second annular recess 270 ″ is lower than the reference plane coupled to the PCB board 130. Counterbore (not shown) can be formed shallowly.

A conductive paste may be applied between the star washer 260 and the second annular groove 270 ″ to help ensure good electrical contact of the star washer 260 at all times.

Cavity filter 18 according to an embodiment of the present invention provides an RF

connection terminal portion

20, 30, 40 including an

elastic connector

240, 340, 440 formed so that the terminal is exposed on both sides or one surface of the height direction. As a result, the thickness of the cavity filter 18 is reduced, whereby a massive MIMO antenna system having a slimmer and more compact laminated structure can be constructed.

The above description is merely illustrative of the technical idea of the present embodiment, and those skilled in the art to which the present embodiment belongs may make various modifications and changes without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment but to describe the present invention, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of the present embodiment should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present embodiment.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is filed with the Korean Patent Application No. 10-2017-0013798 filed in Korea on Jan. 31, 2017 and the patent application No. 10-2017-0074330 filed in Korea on June 13, 2017. (a) Claims priority under section 35 USC § 119 (a), all of which are hereby incorporated by reference in this patent application. In addition, this patent application claims priority to countries other than the United States for the same reasons, all of which are incorporated herein by reference.

Claims

In the cavity filter used in the base station antenna for mobile communication, which is installed on the outer member,

Resonance element;

A first case disposed on the outer member and including the resonance element therein; And

A terminal part electrically connected to the electrode pad of the outer member and the resonance element through the first case, and electrically insulated from the first case;

Including,

The terminal portion,

A terminal insertion hole in which at least a portion of the first case is recessed from a bottom surface of the first case;

A pin member disposed inside the terminal insertion hole, the pin member including one end of which is connected to the resonance element, and a terminal body part extending from the other end of the pin part and having a larger diameter than the pin part; And

It is made of an elastic conductor and is disposed between the terminal body and the electrode pad to electrically connect both sides, and when the cavity filter is installed on the outer member, it is compressed to contact the pin member and the electrode pad. An elastic connector configured to provide;

Cavity filter comprising a.
The method of claim 1,

Further comprising a dielectric bush inserted into the terminal insertion hole,

The terminal insertion hole,

A third insertion opening having a constant gap in the radial direction with the terminal body portion;

A second insertion hole having a diameter smaller than that of the third insertion hole and into which a portion of the dielectric bush is inserted; And

A first insertion hole having a diameter smaller than that of the second insertion hole and into which a portion of the dielectric bush is inserted;

Cavity filter comprising a.
The method of claim 1,

The dielectric bush,

A through-hole is formed in the form of a two-stage cylinder having a first end and a second end having a larger diameter than the first end and penetrating the center of the rotating shaft.

The pin filter is inserted into the through hole from the second end side, and the pin member is fixed to the dielectric bush.
The method of claim 1,

The pin portion,

Cavity filter on the outer circumferential surface comprising a wedge-shaped projection formed so that the pin portion does not fall in the opposite direction inserted into the dielectric bush.
The method of claim 2,

The terminal body portion,

Shorter than the depth of the third insertion hole is formed,

A hollow portion having a cylindrical shape therein; And

A cone-shaped opening that decreases in diameter from the inlet;

Cavity filter comprising a.
The method of claim 5,

The hollow portion,

Cavity filter characterized in that it comprises a first annular groove formed on the inner peripheral surface of the hollow portion.
The method of claim 6,

The elastic connector,

A cylindrical member inserted into the hollow part;

A wedge-shaped annular protrusion protruding from the outer circumferential surface of the cylindrical member;

A conical pin socket contact portion extending from the cylindrical member and inserted into the opening;

An impedance matching portion extending from the pin socket contact portion; And

At least one cutout portion formed along the central axis of the elastic connector from an outer surface exposed to the outside after the elastic connector is inserted into the hollow part;

Including,

The incision extends to a depth passing through the annular protrusion,

The annular projection is a cavity filter, characterized in that formed when the elastic connector is inserted into the hollow portion is accommodated in the first annular groove to prevent the separation of the elastic connector.
The method of claim 7, wherein

Cavity filter from the central axis of the pin socket contact portion is formed 5 to 10 degrees larger than the angular size from the central axis of the opening.
The method of claim 7, wherein

Cavity filter characterized in that the electrode corner formed by the outer surface of the elastic connector and the outer peripheral surface of the impedance matching portion is formed in a round shape of R0.1 to R0.5 range.
The method of claim 6,

And a pin spring in the form of a compression spring inserted between the inner side of the hollow portion and the elastic connector.
The method of claim 5,

The elastic connector,

Most of the length except the end portion is formed from an elongated spring plate having a constant width, the finished form is a circular spring portion, the center portion is formed in a circular shape; And

Two plate-like protrusions projecting perpendicularly to the circumference from two points adjacent to the circumference of the circular spring portion;

Including,

The width of the spring plate is smaller than the diameter of the hollow portion,

The diameter of the circular spring portion is a cavity filter, characterized in that larger than the diameter of the terminal body portion.
The method of claim 11,

The opening is a cavity filter, characterized in that formed at an angle that the circular spring portion circumscribed.
The method of claim 11,

Cavity filter, characterized in that the solder is filled between the hollow portion and the plate-like protrusion inserted into the hollow portion to electrically and mechanically connect the elastic connector and the pin member.
The method of claim 3, wherein

The terminal insertion hole,

Is formed from the bottom surface of the first case,

A fourth insertion hole having a diameter having the same size as that of a large diameter of the two-stage cylinder shape of the dielectric bush and extending side by side on the bottom surface; And

A fifth insertion hole formed at a central position of one side of the fourth insertion hole and into which the first end of the dielectric bush is inserted;

Cavity filter comprising a.
The method of claim 14,

The elastic connector,

A pin insertion hole inserted into the pin portion and supported by the terminal body portion;

A first extension part extending in a direction perpendicular to a central axis of the pin part; And

A second extension part which is bent at an obtuse angle from the first extension part and protrudes outward from the bottom surface of the first case;

Cavity filter, characterized in that the plate spring shape including a.
The method of claim 15,

The terminal body portion,

The outer surface of the terminal body portion is formed to have a predetermined gap from the bottom surface of the first case in the state in which the elastic connector is inserted through the pin insertion hole in the pin portion and the pin member is assembled to the dielectric bush. Cavity filter.
The method of claim 2,

Further comprising a star washer electrically connected to the first case,

The first case further includes a second annular recess surrounding the third insertion hole,

And the second annular recess is formed to accommodate the star washer and at least a portion of the star washer protrudes outward from the bottom surface of the first case.
The method of claim 17,

The second annular groove,

The circumferential surface corresponding to the outer diameter is formed in an annular dovetail shape so that the diameter increases in the depth direction,

The inlet outer diameter of the second annular groove is a cavity filter, characterized in that the star washer is retracted by elasticity is inserted into the second annular groove, the minimum diameter that can be prevented from being separated.
The method of claim 17,

The second annular groove,

A plurality of press-fit pin holes formed around the second annular groove; And

A press-fit pin which is inserted into the press-fit pin hole and is inserted into the bottom surface of the first case and at least partially protrudes into the second annular groove to prevent the star washer from being separated;

Cavity filter comprising a.
The method of claim 17,

The second annular groove,

A caulking hole formed around the second annular groove, the caulking hole being formed in proximity to the second annular groove,

The side wall of the circumferential surface corresponding to the outer diameter of the second annular groove is recessed toward the central axis of the second annular groove by caulking after the star washer is inserted to prevent the star washer from being separated. Cavity Filter.