JP4897028B2 - Coupling electrode unit - Google Patents

Description

  The present invention relates to a coupling electrode unit of a high-frequency coupler used in a UWB communication system using an electrostatic field or an induced electric field, and more particularly, a coupling for positioning and supporting a coupling electrode that is coupled to a communication partner side at a very short distance. The present invention relates to an electrode unit.

  UWB (ultra wide band) communication using an electrostatic field or an induction electric field uses a high frequency band of 3.1 GHz to 10.6 GHz, and can realize wireless data transmission with a large capacity of about 100 Mbps. Compared to the radiation field of an antenna that is attenuated in inverse proportion to the distance, the induction electric field is inversely proportional to the square of the distance, and the electrostatic field is attenuated in inverse proportion to the cube of the distance, so there is no effect on other devices. Since there is no information leakage due to signal leakage, it is attracting attention as a communication method for inputting and outputting moving image and music data to a small information device such as a personal computer.

  Furthermore, since UWB communication uses an electrostatic field or an induction field, there is no need to connect via a USB cable or the like as cableless communication, and only a pair of high-frequency couplers on the transmitter side and the receiver side are brought close to each other. It is known as a communication system capable of transmitting a large amount of data at high speed (Patent Document 1).

  In this UWB communication, a UWB low band of 3.1 to 4.9 GHz is used as a transmission band in the UWB transmission band, and a transmission circuit unit 111 of a transmitter 110 and a reception circuit of a receiver 120 as shown in FIG. The unit 121 is configured to be non-contact coupled by the transmitter-side high-frequency coupler 112 and the reception-side high-frequency coupler 122. Each of the high-frequency couplers 112 and 122 includes plate-like coupling electrodes 113 and 123, series inductors 114 and 124 connected in series to the coupling electrodes 113 and 123, and parallel inductors 115 and 125 connected in parallel. Are arranged symmetrically with each other on the transmission side and the reception side. If the coupling electrodes 113 and 123 are arranged to face each other at a very short distance, they act as parallel plate capacitors and operate like a bandpass filter in the entire high frequency couplers 112 and 122. A high frequency signal is efficiently transmitted between the receiving circuit units 121.

  Here, the distance between the plate-like coupling electrodes 113 and 123 is an extremely short distance of about 3 cm, but corresponds to about ½ wavelength in the 4 GHz frequency band, which is a transmission band, and transmission loss due to impedance mismatching. The impact of is great. Therefore, in order to reduce the reflection of the signal in the coupling unit, the characteristic impedance of the circuit from the transmission circuit unit 111 to the coupling electrode 113 and the characteristic impedance of the circuit from the coupling electrode 123 to the reception circuit unit 121 are matched, Increases transmission efficiency.

  However, when the circuit shown in FIG. 6 is formed of circuit elements that are regarded as lumped constant circuits, the operating frequency band is narrow. Therefore, the high frequency couplers 112 and 122 are replaced with the distributed constant circuit shown in FIG. 130 is constituted. That is, a stub 132 made of a conductor pattern as a distributed constant circuit is printed on the surface of a printed wiring board 131 whose back surface is covered with a ground conductor, instead of the series inductors 114 and 124 and the parallel inductors 115 and 125, and one end of the stub 132 is formed. It is connected to the transmission circuit unit 111 or the reception circuit unit 121 via the signal line pattern 133. The other side of the stub 132 is connected to the ground conductor on the back surface through the through hole 134 and is short-circuited, and a leg portion 135a bent downward from the coupling electrode 135 made of a conductive metal plate at the center position of the stub 132. Are connected by soldering, and the coupling electrode 135 is connected.

  The length of the stub 132 is ½ wavelength of the high-frequency signal, and the signal line pattern 133 and the stub 132 are formed as a microstrip line by wiring on the printed wiring board 4 whose back surface is covered with a ground conductor. The Therefore, the voltage amplitude of the standing wave generated in the stub 132 that is short-circuited at the tip connected to the ground conductor is maximized at the center position where the coupling electrode 135 is connected, and the high-frequency coupler 130 with good propagation efficiency is formed.

  Further, the leg portion 135a of the coupling electrode 135 is formed by bending downward from the center position of the projected shape obtained by projecting the coupling electrode 135 onto the printed wiring board 131, thereby connecting the feeding point to which the high-frequency transmission line is connected. A non-uniform current does not flow along the plane of the coupling electrode 135 between the center of the electrode 135 and an unnecessary radio wave as an antenna is not radiated.

  The coupling electrode 135 configured as described above can be obtained by a simple processing step in which a conductive metal plate is punched out by pressing or the like and then bent. However, as shown in FIG. Since it is not supported, automatic mounting on the printed circuit board 4 is difficult, and after connection to the board 4, it is easily deformed by receiving external force, and transmission characteristics change.

  Therefore, as shown in FIG. 8, a conductor pattern is vapor-deposited or printed on the surface of a rectangular parallelepiped spacer 141 made of an insulator to form a coupling electrode 142, and a stub 143 meandering in a folded manner is vapor-deposited on the back surface. The coupling electrode unit 140 that integrally supports the coupling electrode 142 by connecting the center position of the stub 143 along the wiring direction of the stub 143 and the center of the coupling electrode 142 with a through hole 144 that penetrates the spacer 141. Has also been proposed.

  In the coupling electrode unit 140 configured in this way, one side of the stub 143 is connected to one end of the signal line pattern 146 of the printed wiring board 145, and the other side of the stub 143 is connected to the ground conductor 147 on the back surface of the printed wiring board 145. Surface mounting is performed on the printed wiring board 145 so as to be opposed to the pattern 148, thereby forming a high-frequency coupler.

JP 2008-154198 A

  However, since the coupling electrode 135 is supported in an unstable state as described above, the high-frequency coupler 130 shown in FIG. 7 is easily deformed by an unexpected external force and difficult to be automatically mounted on a printed wiring board. Therefore, it is not suitable for mass production.

  In the coupling electrode unit 140 shown in FIG. 8 that has been improved, the coupling electrode 142 and the stub 143 are integrated with the spacer 141, so that automatic mounting is possible. Since it is necessary to make a connection, a through hole 144 is formed through the spacer 141 downward from the center thereof to conduct to the stub 143. The coupling electrode 142 has a size of about 10 mm in length and 13 mm in width. In other words, it is extremely difficult to form the through-hole 144 and to electrically connect them, which is not practical.

  Further, in order to form the coupling electrode 142 and the stub 143 on the front and back surfaces of the spacer 141 made of an insulator by vapor deposition or printing, high accuracy is required, and the cost increases. On the other hand, a manufacturing method in which a coupling electrode made of a conductive plate material is formed and integrally molded when the spacer is molded is also conceivable. However, the coupling electrode is a microplate, and similarly high accuracy is required for integral molding. In addition, since there is a tolerance in the thickness on the side of the thin coupling electrode, the resin may leak from between the mold and cover the surface, which may deteriorate the performance.

  Further, since the spacer 141 between the coupling electrode 142 and the stub 143 is made of an insulator having a high dielectric constant, electric field coupling with the ground conductor 147 on the back surface of the printed wiring board 145 is facilitated, and the communication band is narrowed. There is a problem in that power transmitted and received by the coupling electrode 142 is transmitted to the ground conductor 147 and communication characteristics deteriorate.

  The present invention has been made in consideration of such conventional problems, and a coupling electrode unit that can be positioned and held securely by simple assembly and can be automatically mounted on a printed wiring board is provided. The purpose is to provide.

  It is another object of the present invention to provide a coupling electrode unit in which power transmitted and received by the coupling electrode does not leak to the ground conductor on the back surface of the printed wiring board even when the height is lowered.

In order to achieve the above object, the coupling electrode unit according to claim 1 is electrically connected to a central position along the wiring direction of the stub on the printed wiring board on which the stub forming the inductor is wired on the surface. A coupling electrode unit in which a coupling electrode is arranged at a predetermined distance from a stub, and is composed of a flat plate-shaped coupling electrode made of a conductive metal, a power supply pin suspended from the center of the back surface of the coupling electrode, and a coupling An insulating spacer that is mounted on the surface of the printed wiring board by positioning and supporting the coupling electrode in parallel with the surface of the printed wiring board at a predetermined interval; The insulating spacer is formed in a frame shape in which a pair of U-shaped arm portions face each other and a part surrounding the coupling electrode is opened, and an engagement step portion facing above the inner wall surface of each arm portion and below Between the engaging projections Around the use electrodes sandwiching an insulating spacer for positioning and supporting the coupling electrode in a state of being mounted on the surface of the printed circuit board surrounding the stub, the lower end of the feed pin being vertically from the coupling electrode in the center of the stub It is characterized by electrical connection.

  Since the coupling electrode is positioned with its periphery engaged with the insulating spacer, it is not easily deformed even when an external force is applied, and the transmission characteristics do not change.

  Since the insulating spacer is formed in a frame shape, a space having a lower dielectric constant than the insulator is formed between the coupling electrode and the surface of the printed wiring board in a state of being mounted on the surface of the printed wiring board. The coupling electrode and the ground conductor on the back surface of the printed wiring board are hardly electrically coupled.

Further , the insulating spacer is formed in a frame shape in which a pair of U-shaped arm portions face each other and a part surrounding the coupling electrode is opened, and an engagement step portion facing above the inner wall surface of each arm portion; It is characterized in that the periphery of the coupling electrode is sandwiched between the engaging projection facing downward and the coupling electrode is positioned and supported.

  Since the insulating spacer is formed in a frame shape in which a part surrounding the coupling electrode is opened, the pair of opposing U-shaped arm portions is elastically deformed, and the pair of U-shaped arm portions is elastically deformed. The coupling electrode is accommodated and can be easily sandwiched between the engaging step portion and the engaging protrusion. By mounting an insulating spacer that positions and supports the coupling electrode on the surface of the printed wiring board, the pair of U-shaped arms are fixed to the printed wiring board, so that the gap between them opens and the coupling electrode falls off. There is nothing.

Further, in the coupling electrode unit according to claim 2 , the leg portion of the spacer frame portion inserted into the mounting hole of the printed wiring board has two steps with the outer diameter of the base end portion above the tip portion being large. When an insulating spacer is mounted on a printed wiring board formed separately and having a first mounting hole in which the base end part is loosely fitted, the coupling electrode and the stub are electrically connected by the first-length power supply pin. When the insulating spacer is mounted on the printed wiring board in which the distal end is loosely fitted and the second mounting hole having a smaller diameter than the outer diameter of the proximal end is formed, the power supply pin having the second length longer than the first length And the coupling electrode and the stub are electrically connected.

  By combining two types of printed wiring boards in which either the first mounting hole or the second mounting hole is formed and two types of power supply pins of the first length and the second length, the common insulating spacer can be coupled. Two types of coupling electrode units having different heights from the surface of the printed wiring board to the coupling electrode are obtained using the coupling electrodes.

  According to the first aspect of the present invention, the coupling electrode can be obtained by a simple process of pressing a metal plate, and the coupling electrode is easily assembled integrally without rattling by engaging the insulating spacer. Can be automatically mounted on a printed circuit board.

  In addition, since the coupling electrode is positioned by engaging the insulating spacer, the coupling electrode is not easily deformed even when an external force is applied, and the transmission characteristics do not change.

  In addition, since a space with a lower dielectric constant than the insulator is formed between the coupling electrode and the surface of the printed wiring board, even if the coupling electrode and the printed wiring board are brought close to each other, the coupling can be achieved. The power transmitted / received by the electrode for use does not leak to the ground conductor on the back surface of the printed wiring board.

In addition, since the pair of U-shaped arms are elastically deformed, it can be assembled with a snap-in that engages the insulating spacer around the coupling electrode with a light pressing force, and the insulating spacer is forcedly deformed and damaged. There is nothing. Moreover, after positioning and supporting the coupling electrode, the insulating spacer is mounted on the surface of the printed wiring board, and the pair of U-shaped arms are fixed to the printed wiring board. There is nothing to do.

  In addition, since a part of the frame shape opens between the pair of U-shaped arms, the electrical connection state of the lower end of the power supply pin and the stub can be visually confirmed through the opening, and the coupling electrode is formed during the manufacturing process. And poor connection between the star section.

According to the invention of claim 2 , by using the common insulating spacer and the coupling electrode, the gap between the coupling electrode unit and the ground conductor, which are required to be reduced in height, from the ground conductor to the coupling electrode is secured to improve performance. Any of the coupling electrodes can be manufactured.

FIG. 1 is an exploded perspective view of a coupling electrode unit 1 according to an embodiment of the present invention mounted on a printed wiring board 10. FIG. 2 is a plan view of the coupling electrode unit 1 mounted on the printed wiring board 10. FIG. 3 is an exploded cross-sectional view of FIG. 1 taken along the line AA in FIG. FIG. 4 is a longitudinal sectional view showing a state in which the coupling electrode unit 1 is mounted on the printed wiring board 10 in which the small-diameter second mounting holes 12 are formed. FIG. 5 is a longitudinal sectional view showing a state in which the coupling electrode unit 1 is mounted on the printed wiring board 10 in which the large-diameter first attachment holes 11 are formed. FIG. 6 is a circuit diagram of the high frequency couplers 112 and 122. FIG. 7 is a perspective view showing a conventional high-frequency coupler 130. FIG. 8 is a perspective view showing a conventional coupling electrode unit 140.

  Hereinafter, a coupling electrode unit 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6. The coupling electrode unit 1 is used in UWB communication using an electrostatic field or an induction field having a UWB low band of 3.1 to 4.9 GHz in the transmission band, and high frequency couplers 112 and 122 shown in FIG. The lumped constant circuit is a distributed constant circuit, and the coupling electrode 2 corresponding to the coupling electrodes 113 and 123 is positioned and supported.

  As described above, in the UWB communication between the transmission circuit unit 111 of the transmitter 110 and the reception circuit unit 121 of the receiver 120, the coupling electrodes 113 and 123 of the transmitter-side high-frequency coupler 112 and the reception-side high-frequency coupler 122 are used. Are opposed to each other at an extremely short distance of about 3 cm, and a parallel plate capacitor is formed by both. Since the series inductors 114 and 124 are connected in series and the parallel inductors 115 and 12 are connected in parallel between the coupling electrodes 113 and 123 and the transmission circuit unit 111 or the reception circuit unit 121, the high-frequency coupler 112, The whole 122 operates like a bandpass filter, and a high-frequency signal is efficiently transmitted between the transmission circuit unit 111 and the reception circuit unit 121.

  Here, if the high-frequency couplers 112 and 122 are constituted by circuit elements having the lumped constant circuit shown in FIG. 6, the operating frequency band is narrow. Therefore, the distributed constant circuit is considered to operate in a wide band, and the coupling shown in FIG. The electrode unit 1 and the stub 15 formed on the surface of the printed wiring board 10 are configured.

  The coupling electrode unit 1 includes a sheet metal coupling electrode 2, an insulating spacer 3 that engages with the periphery of the coupling electrode 2, and horizontally positions and supports the coupling electrode 2, and a back side figure of the coupling electrode 2. It consists of a feed pin 4 that is vertically suspended from the center.

  The coupling electrode 2 is made by punching a metal plate such as phosphor bronze having springiness and conductivity into a substantially rectangular shape having a length of 10 mm and a width of 13 mm together with a strip-like piece projecting in the longitudinal direction. The pair of engaging pieces 2a and 2a are integrally connected continuously by bending downward in an L-shaped cross section. The thickness of the coupling electrode 2 is as thin as 0.15 mm. Therefore, as will be described later, when the engagement piece 2a comes into contact with an engagement protrusion 34 (to be described later) of the insulating spacer 3, the entire length along the longitudinal direction is reduced. Bend. In addition, a cylindrical hole 6 through which the power supply pin 4 is inserted is formed by burring processing from the front surface to the back surface at a position that becomes a substantially rectangular figure center.

  As shown in FIG. 3, the power feed pin 4 is a cylindrical conductive metal rod cut into a truncated cone shape that gradually tapers downward, and the inner diameter of the cylindrical hole 6 of the coupling electrode 2. The outer diameter of the upper part is larger than that of the lower part, and the lower part is smaller. As a result, the lower end portion 4a of the power supply pin 4 is inserted from above the cylindrical hole 6 so that the power supply pin 4 can be press-fitted into the cylindrical hole 6, and the upper part reaches the cylindrical hole 6 as shown in FIG. It is fixed in a state suspended from the coupling electrode 2 at the position.

  The insulating spacer 3 is formed of a heat-resistant and insulating synthetic resin such as a heat-resistant liquid crystal polymer (CCP) into a rectangular frame shape surrounding the substantially rectangular coupling electrode 2 as shown in FIG. Thus, one end of a pair of U-shaped arm portions 31 and 32 opposed in the longitudinal direction is integrally connected by a connecting portion 33 along the longitudinal direction. As a result, the rectangular frame-shaped insulating spacer 3 opens at the other end of the U-shaped arm portions 31, 32, and the pair of U-shaped arm portions 31, 32 are elastically deformable around the connecting portion 33. ing.

  Engaging protrusions 34 that engage with the engaging pieces 2a and 2a of the coupling electrode 2 are formed on the opposing inner wall surfaces of the pair of U-shaped arm portions 31 and 32, respectively, with the lower part opened, and Except for the portion of the engagement protrusion 34, an engagement step portion 35 is formed upward on the inner wall surface of the rectangular frame-shaped insulating spacer 3 along the upper edge of the inner wall surface. The height of the engagement step 35 to the upper edge of the inner wall corresponds to the thickness (0.15 mm) of the coupling electrode 2, thereby positioning and supporting the periphery of the coupling electrode 2 without rattling with the insulating spacer 3. To do.

  Legs for positioning the coupling electrode unit 1 on the surface of the printed wiring board 10 are inserted into the first mounting holes 11 or the second mounting holes 12 of the printed wiring board 10 at the four corners of the rectangular frame shape of the insulating spacer 3. The parts 36, 36,. Each leg portion 36 has a two-stage cylindrical shape in which the outer diameter of the distal end portion 36 a is smaller than the inner diameter of the second mounting hole 12 and the outer diameter of the base end portion 36 b is larger than the inner diameter of the second mounting hole 12. The first mounting hole 11 of the printed wiring board 10 has an inner diameter for loosely fitting the base end portion 36b. Therefore, when the mounting hole of the printed wiring board 10 is the first mounting hole 11, FIG. As shown in FIG. 4, when the base end portion 36b of the leg portion 36 is inserted into the second mounting hole 12, the tip end portion 36a is inserted and the base end portion 36b is connected to the printed wiring board as shown in FIG. 10 abuts against the surface.

  The printed wiring board 10 on which the coupling electrode unit 1 is mounted has its back surface covered with a ground conductor 16. This is to completely block high-frequency signals flowing to the stub 15 and the coupling electrode 2 from other circuit elements and patterns arranged on the back side of the printed wiring board 10 in the electronic device.

  The length of the stub 15 printed and formed on the surface side of the printed wiring board 10 is 4 cm, which corresponds to about 1/2 wavelength of the 4 GHz frequency band which is a transmission band, but the upper part is approximately 10 mm long and 13 mm wide. As shown in FIG. 1, the stub 15 is formed so that the length along the meandering wiring direction is approximately ½ wavelength so as to be covered with the rectangular coupling electrode 2.

  The front end side of the stub 15 is connected to the ground conductor 16 on the back surface through a through hole 17 formed in the printed wiring board 10 and is grounded. A signal pattern 15a is drawn out from the base end side of the stub 15, and ground patterns 16a connected to the ground conductor 16 through the through holes 18 are wired on both sides of the signal pattern 15a with a predetermined insulation interval. A signal terminal and a ground terminal of a coaxial connector (not shown) are solder-connected to the signal pattern 15a and the ground pattern 16a, respectively, and the signal pattern 15a is connected to the coaxial circuit connected to the coaxial connector by the transmission circuit unit shown in FIG. 111 or the receiving circuit unit 121.

  By forming the stub 15 on the surface of the printed wiring board 10 whose back surface is covered with the ground conductor 16, a microstrip line that matches the characteristic impedance of the coaxial cable connected to the coaxial connector is formed. Accordingly, a standing wave having a maximum voltage amplitude is generated at the central position along the wiring direction of the stub 15 without being reflected at the coupling portion with the stub 15 or the tip of the stub 15.

  The feeding pin 4 suspended from the coupling electrode 2 is inserted into the first mounting hole 11 or the second mounting hole 12 of the printed wiring board 10 by inserting the leg portions 36, 36,. In a state where 1 is positioned, the lower end portion 4a is close to the center position of the stub 15.

  The high-frequency coupler is formed by mounting the coupling electrode unit 1 having the above-described configuration on the surface of the printed wiring board 10 on which the stub 15 is formed. Hereinafter, a method of forming this high frequency coupler will be described. First, a pair of engaging pieces 2a and 2a projecting in the longitudinal direction of the coupling electrode 2 in the shape of a rectangular sheet metal are brought into contact with the engaging protrusions 34 of the insulating spacer 3 from above and pressed downward. As a result, the pair of U-shaped arm portions 31 and 32 are slightly elastically deformed around the connecting portion 33, the space between the pair of engaging projections 34 and 34 is expanded, and the coupling electrode 2 is also curved in the longitudinal direction. The pair of engaging pieces 2 a and 2 a get over the engaging protrusion 34, and the periphery of the coupling electrode 2 abuts on the engaging step portion 35. As a result, the coupling electrode 2 is attached to the insulating spacer 3 by snap-in, and in the attached state, the inner wall surfaces of the U-shaped arm portions 31 and 32 and the connecting portion 33 in the horizontal direction. In the vertical direction, the periphery and the engagement piece 2a are sandwiched between the front surface of the engagement step portion 35 and the back surface of the engagement protrusion 24, and are positioned and fixed.

  Subsequently, the insulating spacer 3 to which the coupling electrode 2 is attached is attached to the surface of the printed wiring board 10 in which cream solder is printed in advance on the center position of the stub 15, the signal pattern 15a, and the ground pattern 16a. Here, assuming that the second mounting hole 12 is formed in the printed wiring board 10, the distal end portion 36 a of each leg portion 36 is inserted into the second mounting hole 12, and the insulating spacer 3 is formed on the surface of the printed wiring board 10. Position.

  Thereafter, the lower end 4 a of the power supply pin 4 is inserted into the cylindrical hole 6 of the coupling electrode 2 from above and press-fitted. When the insulating spacer 3 is attached to the printed wiring board 10 in which the second attachment holes 12 are formed, as shown in FIG. 4, the height H1 from the stub 15 to the coupling electrode 2 is high as shown in FIG. Since it is higher than the height H2, the relatively long power supply pin 4 is used and press-fitted until the lower end portion 4a reaches the cream solder printed on the stub 15.

  Before and after this step, a coaxial connector is arranged so that the signal terminal and the ground terminal are in contact with the signal pattern 15a and the ground pattern 16a, and the entire printed wiring board 10 on which the coupling electrode unit 1 and the coaxial connector are mounted is reflowed. The coupling electrode unit 1 is surface-mounted through a furnace. After the reflow process, the coupling electrode unit 1 can visually recognize the soldered portion between the lower end portion 4a of the power feed pin 4 and the stub 15 from the opening between the pair of U-shaped arm portions 31 and 32, and prevents poor solder connection. it can. In addition, since each leg portion 36 of the insulating spacer 3 is inserted into the second mounting hole 12 and mounted on the surface of the printed wiring board 10, the gap between the pair of U-shaped arm portions 31 and 32 is opened after mounting. There is no fear of the coupling electrode 2 dropping off.

  By this reflow process, the coupling electrode 2 has a graphic center electrically connected to the center position of the stub 15 via the feed pin 4 and connected to the transmission circuit unit 111 or the reception circuit unit 121 via the coaxial cable. A vessel is formed.

  According to the coupling electrode unit 1 according to the present embodiment, the periphery of the sheet-metal coupling electrode 2 is positioned and supported by the insulating spacer 3, so that automatic mounting is possible, and even if an inadvertent external force is applied. There is no deformation.

  In addition, since the electrical connection is made with the stub 15 which is a high-frequency transmission line at the center of the figure of the coupling electrode 2, non-uniform current along the plane of the coupling electrode 2 between the feeding point and the center of the coupling electrode 2. Does not flow and does not radiate unnecessary radio waves as an antenna.

  In the present embodiment, the height H1 from the surface of the printed wiring board 10 shown in FIG. 4 is 2.6 mm, and the thickness of the printed wiring board 10 is 0.6 mm. A sufficient distance of 3.2 mm is secured between the ground conductors 16 on the back side of the wiring board 10. Further, since the space between the printed wiring board 10 on which the coupling electrode 2 and the stub 15 are wired is a space having a lower dielectric constant than an insulator such as a synthetic resin, the space between the coupling electrode 2 and the ground conductor 16 is between. Electric field coupling is difficult, and a high-frequency signal flowing through the coupling electrode 2 does not leak to the ground conductor 16.

  In contrast to the above-described embodiment, a common coupling can be achieved by simply preparing the printed wiring board 10 in which the first mounting holes 11 into which the base ends 36b of the respective leg portions 36 are loosely fitted and the shorter power supply pins 4 are prepared. By using the electrode 2 and the insulating spacer 3, the coupling electrode unit 1 can be further reduced in height as shown in FIG. The height H2 from the surface of the printed wiring board 10 of the coupling electrode unit 1 loosely fitted to the base end portion 36b of each leg portion 36 in the first mounting hole 11 is 2.0 mm. The distance between the coupling electrode 2 with a thickness of 0.6 mm and the ground conductor 16 is 2.6 mm, but the space between the coupling electrode 2 and the printed wiring board 10 is a low dielectric constant. A high frequency signal flowing through the coupling electrode 2 is unlikely to leak into the ground conductor 16.

  In the above embodiment, the insulating spacer 3 is disposed on the surface of the printed wiring board 10 and then the power supply pin 4 is press-fitted and attached to the coupling electrode 2. However, the power supply pin is attached to the insulating spacer 3 to which the coupling electrode 2 is attached. 4 may be press-fitted and attached, and the coupling electrode unit 1 assembled integrally may be mounted on the surface of the printed wiring board 10.

  Further, in the above embodiment, the power feed pin 4 is formed separately from the coupling electrode 2 by grinding, but the power feed pin 4 and the coupling electrode 2 are integrated in a process such as drawing a conductive metal plate. It may be formed.

  It is suitable for a high-frequency coupler used in a UWB communication system that uses an electrostatic field or an induction field.

DESCRIPTION OF SYMBOLS 1 Coupling electrode unit 2 Coupling electrode 2a Engagement piece 3 Insulating spacer 4 Feeding pin 4a Lower end part 5 Engagement step part 6 Cylindrical hole 10 Printed wiring board 11 1st attachment hole 12 2nd attachment hole 15 Stub 15a Signal pattern 16 Ground conductor 17 Through hole 31 U-shaped arm portion 32 U-shaped arm portion 33 Connecting portion 34 Engaging projection 35 Engaging step portion 36 Leg portion 36a Tip portion 36b Base end portion

Claims (2)

This is a coupling electrode unit in which a coupling electrode that is electrically connected to a central position in the wiring direction of the stub is arranged at a predetermined distance from the stub on a printed wiring board on which a stub forming an inductor is formed on the surface. And
A flat coupling electrode made of a conductive metal;
A feed pin suspended from the center of the back surface of the coupling electrode;
An insulating spacer formed on the surface of the printed wiring board is formed in a frame shape that engages the periphery of the coupling electrode, and is positioned and supported in parallel with the surface of the printed wiring board at a predetermined interval. ,
The insulating spacer is formed in a frame shape in which a pair of U-shaped arms face each other and a part surrounding the coupling electrode is opened,
Printed wiring that surrounds the stub with an insulating spacer that positions and supports the coupling electrode by sandwiching the periphery of the coupling electrode between the engagement step portion facing above the inner wall surface of each arm and the engagement protrusion facing downward A coupling electrode unit, wherein a lower end portion of a power supply pin suspended from a coupling electrode is electrically connected to a center of a stub in a state of being mounted on a surface of a substrate. The leg portion of the spacer frame portion to be inserted into the mounting hole of the printed wiring board is formed in two steps with the outer diameter of the base end portion above the tip portion being large,
When mounting the insulating spacer on the printed wiring board in which the first mounting hole in which the base end part is loosely fitted is formed, the coupling electrode and the stub are electrically connected by the first length of the power supply pin,
When mounting the insulating spacer on the printed wiring board in which the distal end portion is loosely fitted and the second mounting hole having a diameter smaller than the outer diameter of the proximal end portion is formed, a power supply pin having a second length longer than the first length is used. The coupling electrode unit according to claim 1 , wherein the coupling electrode and the stub are electrically connected.

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