JP2008072545A - Output connector of microphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably prevent the entry of a high-frequency current into a microphone caused by strong electromagnetic waves radiated from a portable telephone, or the like with simple configurations and assemblies. <P>SOLUTION: In a three-pin type output connector, a first pin E for grounding, a second pin SH for signals, and a third pin SC pass through a connector substrate 11. The three-pin type output connector has a printed-wiring board 100 comprising a double-sided substrate arranged at the side of a substrate internal surface 11a of the connector substrate 11 by inserting three pins E, SH, SC. On a substrate upper surface 101 of the printed-wiring board 100, a shield layer 120, which comprises a solid pattern of copper foil that is not conductive to the second and third pins SH, SC but is conductive to the first pin E, is formed on nearly the entire surface of the substrate upper surface 101. On a substrate lower surface 102 of the printed-wiring board 100, a filter circuit 130, which includes a capacitor element 131 for preventing the high-frequency current from entering a microphone case, is formed. The pin insertion hole of the printed-wiring board 100 is arranged eccentrically to a corresponding pin. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a microphone output connector, and more particularly, to a technology for preventing high frequency electromagnetic waves generated from, for example, a mobile phone from entering the microphone case through the output connector. is there.

  The condenser microphone has a built-in impedance converter such as a FET (field effect transistor) because the impedance of the microphone unit is extremely high. Normally, a condenser microphone uses a phantom power source, and a microphone audio signal is output to a mixer or the like via a balanced shield cable for the phantom power source.

  In order to connect the balanced shielded cable, a 3-pin type output connector is provided on the side of the microphone case (microphone grip in a handheld microphone) (see, for example, Patent Document 1). The output connector is a connector defined in EIAJ RC-5236 “Latch Lock Type Circular Connector for Audio Equipment”, and its configuration will be described with reference to FIGS.

  7 is a cross-sectional view showing the output connector mounted in the microphone case, FIG. 8 is a front view showing the output connector extracted from the microphone case, and in FIG. 7, the output connector is taken along line BB in FIG. It is shown in cross section. FIG. 9 is a plan view of the output connector.

  According to this, the output connector 10 includes a disk-shaped connector base 11 made of an electrical insulator such as PBT (polybutadiene terephthalate) resin. The connector base 11 is provided with three pins, that is, a first pin E for grounding, a second pin SH on the signal hot side, and a third pin SC on the cold side of the signal, for example, by press-fitting.

  In the case of a handheld microphone, as shown in FIG. 7, the output connector 10 is mounted in a connector storage tube 20 that is screwed to the end of the microphone grip. Normally, the microphone grip including the connector housing cylinder 20 is made of a metal material such as brass, and also acts as a shield case for the built-in electrical parts.

  A male screw 12 for electrically connecting the first pin E for grounding to the connector housing cylinder 20 is provided in the connector base 11. The male screw 12 is accommodated in a screw accommodation hole 13 formed in the radial direction of the connector base 11, and the female screw 14 a that engages with the male screw 12 in the screw accommodation hole 13 in the connector base 11. There is provided a ground terminal plate 14 having.

  As shown in the plan view of FIG. 9, the ground terminal plate 14 and the first pin E for grounding are electrically connected via the connection fitting 15. As shown in FIG. 7, the male screw 12 is turned from a round hole 21 formed in the connector housing cylinder 20 by a driver (not shown) to bring the male screw 12 into contact with the periphery of the round hole 21.

  As a result, the first pin E for grounding and the connector housing cylinder 20 are electrically connected via the male screw 12, the ground terminal plate 14 and the connection fitting 15. In addition, as shown in FIGS. 8 and 9, a leaf spring 16 in contact with the inner surface of the connector housing cylinder 20 is connected to the first pin E for grounding, and the first pin for grounding is connected by the leaf spring 16. E and electrical connection between the connector housing cylinder 20 may be taken.

  When a microphone cable (balanced shielded cable) drawn from the phantom power source (not shown) is connected to the output connector 10, if a strong electromagnetic wave is applied to the microphone or the microphone cable, the electromagnetic wave is transmitted from the output connector 10 to the inside of the microphone. May be demodulated by the impedance converter and output from the microphone as audible noise.

  As one of the methods for preventing the electromagnetic wave from entering the microphone from the output connector 10 as described above, conventionally, between the first pin E for grounding and the second pin SH on the hot side, and the first one for grounding. Capacitor elements that operate to short-circuit the high frequency are connected between the pin E and the third pin SC on the cold side, and the high frequency intrusion is prevented between the second pin SH on the hot side and the third pin SC on the cold side. It connects with microphone cases, such as connector storage cylinder 20, via the inductor element for this.

  According to this, it is possible to prevent intrusion of electromagnetic waves caused by normal broadcast radio waves, such as HF, VHF, UHF and the like, with almost no problem. However, due to the recent spread of mobile phones and the like, there is an increased chance that higher frequency electromagnetic waves are used in the vicinity of the microphone, and this type of high frequency electromagnetic waves may not be effective.

  That is, the output connector 10 is provided with three pins E, SH, and SC, but there is an unshielded portion where electromagnetic waves enter between the pins. Further, since the portion of the output connector 10 that is grounded to the connector housing cylinder 20 is the above-described male screw 12 for fixing and / or the leaf spring 16 attached to the first pin E for grounding, the contact portion is a high frequency. Has high impedance and is not sufficiently grounded in terms of high frequency.

  Therefore, even if a capacitor circuit and an inductor element are connected as described above to configure a filter circuit that blocks high frequencies, a sufficient effect may not be obtained for high frequencies used in mobile phones and the like. .

  The capacitor element included in the filter circuit operates so as to pass high-frequency current well. For this reason, it is not preferable that the capacitor element is within the microphone shield because a high-frequency current flows through the capacitor element and induces a high-frequency current in peripheral components and circuit patterns.

  In addition, the capacitor has a maximum rated voltage, and when a voltage exceeding this is applied, the capacitor is destroyed. A completely destroyed capacitor loses its function as a capacitor. However, if the degree of destruction is low, the function of the capacitor is maintained to some extent, which may cause noise as a new cause.

  Therefore, the present applicant has filed an application for a microphone output connector that has solved the above-mentioned problems (see Patent Document 2). The microphone output connector described in Patent Document 2 includes a printed wiring board disposed on the connector base and a shield cover that covers the printed wiring board. The printed wiring board is a double-sided board and a copper foil on the lower surface side of the board. A capacitor layer for preventing high-frequency penetration and a Zener diode element for preventing circuit breakdown due to static electricity are mounted in parallel on the upper surface side of the board, and almost the entire upper surface of the board is shielded. The configuration of being covered with a cover is adopted.

  According to this configuration, each of the three pins penetrating the connector base is electromagnetically shielded by the shield layer of the printed wiring board. In addition, a capacitor element for preventing high-frequency penetration and a Zener diode element for preventing circuit destruction due to static electricity are mounted in parallel on the upper surface (component mounting surface) of the printed wiring board. Therefore, high frequency is prevented from being radiated from the wiring leading to the capacitor to the inside of the microphone. In addition, the capacitor element can be protected from electrostatic breakdown by the Zener diode element.

  However, since a shield cover that covers the upper surface side that is the component mounting surface of the printed wiring board is required, first, the cost is increased. For example, when the design specifications are old and it is difficult to change the 3-pin plug, or when the designated connector must be used, the configuration of the microphone output connector described in Patent Document 2 is applied. There are times when you can't. In such a case, a new mold is raised to produce a connector that can be adapted to it, but this is uneconomical and undesirable.

Japanese Patent Application Laid-Open No. 11-341583 JP 2005-311752 A

  Therefore, an object of the present invention is to provide a low-cost microphone that can reliably prevent the high-frequency current from entering the microphone due to strong electromagnetic waves radiated from a mobile phone or the like while being simple in configuration and assembly. To provide an output connector.

  In order to solve the above problems, the invention according to claim 1 is a three-pin structure in which a grounding first pin, a signal second pin, and a third pin are provided through a connector base made of an electrical insulator. This type of output connector is a microphone output connector that is mounted in a state where the first pin is electrically connected to the microphone case in the end portion of the conductive microphone case of the condenser microphone. A printed wiring board disposed on the inner side of the base facing the inside of the microphone case of the connector base, and the printed wiring board is a double-sided board on the upper surface of the board opposite to the inner surface of the base. A shield layer made of a solid pattern of copper foil that is non-conductive with respect to the second pin and the third pin and conductive with the first pin is formed over almost the entire upper surface of the substrate. A filter circuit including a capacitor element that prevents high-frequency current from entering the microphone case is formed on the lower surface of the substrate facing the inner surface of the base, and a pin insertion hole formed in the printed wiring board is provided. It is characterized by being arranged eccentrically with respect to the corresponding pin.

  According to a second aspect of the present invention, there is provided a first pin insertion hole for the first pin, a second pin insertion hole for the second pin, and a third pin for the third pin. Each of the pin insertion holes is the same diameter hole having a diameter larger than that of each of the pins, and the difference between the radius of each of the pin insertion holes and each of the pins is Δt, and the first through third pin insertion holes are Any one of the pin insertion holes is eccentrically arranged in the first direction by at least the difference Δt with respect to the corresponding pin, and the remaining two pin insertion holes are in the first direction with respect to the corresponding pins. It is characterized in that it is decentered at least by the difference Δt in a second direction opposite to the first direction.

  According to a third aspect of the present invention, the third pin insertion hole is arranged eccentrically at least by the difference Δt toward the center side or the opposite center side of the connector base with respect to the corresponding third pin. The first pin insertion hole and the second pin insertion hole are eccentrically arranged at least by the difference Δt in the direction opposite to the third pin insertion hole with respect to the first pin and the second pin. It is characterized by being.

  According to the first aspect of the present invention, a shield layer made of a solid pattern of copper foil is formed on the upper surface of the substrate opposite to the inner surface of the base of the connector base of the printed wiring board made of double-sided board, A filter circuit including a capacitor element that prevents high-frequency current from entering the microphone case is formed on the lower surface of the substrate facing the inner surface, so that the three printed circuit boards are embedded in the connector base. Since the capacitor element is placed outside the microphone shield by the shield layer on the top surface of the board without installing a separate shield cover, it is only necessary to insert it through the pin of the microphone, so that the outside of the microphone shield The high frequency current that flows through the capacitor element due to electromagnetic waves does not flow, thereby suppressing the generation of noise.

  In addition, since it is not necessary to provide a separate shield cover, the cost can be reduced and the position of the pin plug for an existing model with an old design specification that is difficult to change. It is possible to cope with this by simply drilling a pin insertion hole in the printed wiring board.

  According to the second aspect of the present invention, the first pin insertion hole for the first pin, the second pin insertion hole for the second pin, and the third pin for the third pin are formed in the printed wiring board. Each of the pin insertion holes is the same diameter hole having a larger diameter than each pin, and Δt is a difference between the radius of each pin insertion hole and the radius of each pin, and any one of the first to third pin insertion holes. One pin insertion hole is arranged eccentrically at least by the difference Δt in the first direction with respect to the corresponding pin, and the first two directions with respect to the corresponding pins are the remaining two pin insertion holes. By disposing at least the difference Δt in the opposite second direction, the printed wiring board can be fixed at a predetermined position simply by inserting the printed wiring board through the three pins.

  In the connector specified in EIAJ RC-5236 “Latch Lock Type Circular Connector for Audio Equipment”, the 1st to 3rd pins are arranged almost at the vertices of the isosceles triangle, the 3rd pin is the 1st pin and 2 According to the invention described in claim 3, the third pin insertion hole is directed toward the center side or the opposite center side of the connector base with respect to the corresponding third pin. The first pin insertion hole and the second pin insertion hole are arranged eccentrically by at least the difference Δt, and at least the difference Δt in the direction opposite to the third pin insertion hole with respect to the corresponding first pin and second pin. By being arranged eccentrically only, the printed wiring board can be stably fixed to the three pins.

  Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 6, but the present invention is not limited to this. 1 is a front view showing a microphone output connector 10A according to the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is a plan view.

  The output connector 10A of the present invention includes a connector base 11 formed in a disc shape from a synthetic resin such as PBT as a basic configuration, similar to the conventional output connector 10 described with reference to FIGS. The connector base 11 is provided with three pins, for example, press-fitting, for example, a first pin E for grounding, a second pin SH on the signal hot side, and a third pin SC on the cold side of the signal.

  The connector base 11 is provided with a male screw 12 for fixing to the connector storage portion 20 (see FIG. 7). The male screw 12 is screwed with a female screw 14 a of the ground terminal plate 14 in a screw housing hole 13 formed in the connector base 11 in the radial direction. The ground terminal plate 14 is erected on the connector base 11 and is electrically connected to the first pin E for grounding via the connection fitting 15 as shown in FIG.

  According to the present invention, for example, in order to prevent an electromagnetic wave having a high frequency radiated from a mobile phone from entering the inside of the microphone (inside the microphone case), the inner surface of the base of the connector base 11 (the surface disposed on the inner side of the microphone). ) The printed wiring board 100 is disposed on the 11a side.

  The printed wiring board 100 is attached to the output connector 10A by being inserted into the three pins E, SH, and SC. The printed wiring board 100 is a double-sided board. The surface opposite to the base inner surface 11a of the connector base 11 is the substrate upper surface 101, and the surface opposite to the base inner surface 11a is the substrate lower surface 102. FIG. 4A shows the substrate upper surface 101, and FIG. 4B shows the substrate lower surface 102.

  According to the third triangulation method of drawing, the bottom view (bottom view) of FIG. 4 (b) is expressed vertically symmetrically with respect to the top view (plan view) of FIG. 4 (a). For the sake of convenience, FIG. 4B is a perspective view seen from the side of FIG. FIG. 4C shows a plan view of the connector base 11 with the printed wiring board 100 removed.

  4A and 4C, the printed wiring board 100 has three pin insertion holes, that is, a first pin insertion hole 111 through which the first pin E for grounding is inserted, and a second pin on the hot side. A second pin insertion hole 112 through which SH is inserted and a third pin insertion hole 113 through which the third pin SC on the cold side is inserted are provided. The printed wiring board 100 is also provided with a terminal board insertion hole 114 for the ground terminal board 14.

  Referring to FIG. 4A, the shield layer 120 is formed on the upper surface 101 of the printed wiring board 100 except for the second pin insertion hole 112 and the third pin insertion hole 113, as shown by hatching. It is formed over almost the entire surface as a solid pattern made of foil.

  The shield layer 120 is not electrically connected to the signal 2nd pin SH and the 3rd pin SC, but penetrates into the first pin insertion hole 111 and the terminal plate insertion hole 114 by through-hole plating and is used for grounding. The first pin E and the ground terminal plate 14 are electrically connected. Thus, since the first pin E for grounding and the ground terminal plate 14 are electrically connected via the shield layer 120, the connection fitting 15 shown in FIG. 9 may be omitted. In the second pin insertion hole 112 and the third pin insertion hole 113, through-hole plating is applied to ensure electrical continuity with the signal pins SH and SC.

  Referring to FIG. 4B, a filter circuit that prevents high-frequency current caused by external electromagnetic waves or the like from entering a microphone case (not shown) via the output connector 10A on the lower surface 101 of the printed wiring board 100. 130 is provided.

  In this example, the filter circuit 130 includes a capacitor element 131 and a Zener diode element 132 in parallel. The filter circuit 130 is connected between the 1st pin E and the 2nd pin SH and between the 1st pin E and the 3rd pin SC, as shown in the equivalent circuit of FIG.

  The Zener diode element 132 is a capacitor from an inrush current that flows from the second pin SH on the signal side and the third pin SC to the first pin E side when a strong electromagnetic wave is applied to a microphone cable (not shown) connected to the output connector 10A. It is provided to protect the element 131.

  The printed wiring board 100 has the board upper surface 101 on the upper side and the board lower surface 102 on the lower side, and the pin insertion holes 111, 112, 113 are inserted into the pins E, SH, SC, and the terminal board insertion hole 114 is grounded. By inserting through the terminal board 14, as shown in FIGS. 1 and 2, the connector base 11 is mounted at a predetermined position on the base inner surface 11a side.

  According to this, since the capacitor element 131 on the substrate lower surface 102 side is arranged outside the microphone shield in the shield layer 120 on the substrate upper surface 101 side, the microphone shield is caused by external electromagnetic waves. The high-frequency current flowing through the capacitor element does not flow, thereby suppressing the generation of noise due to external electromagnetic waves.

  Further, in the present invention, the printed wiring board 100 can be fixed to the pins E, SH, and SC without using a separate fixing means such as screws or adhesives. And the position of each pin insertion hole 111, 112, 113 corresponding to this is shifted relatively.

  Since the positional relationship between each pin E, SH, SC and each pin insertion hole 111, 112, 113 is the same, FIG. 5 shows the second pin SH and the corresponding second pin insertion hole 112 as an example. I will explain.

  As shown in FIG. 5A, in the present invention, the second pin insertion hole 112 is formed to have a larger diameter than the second pin SH. The radius of the second pin SH is R1, the radius of the second pin insertion hole 112 is R2, and the difference (R2−R1) is Δt. As shown in FIG. 5B, the center pin C1 of the second pin SH is On the other hand, the center point C2 of the second pin insertion hole 112 is decentered by at least Δt, and the second pin insertion hole 112 is brought into contact with the second pin SH.

  The printed wiring board 100 is fixed (held) to the pins E, SH, and SC by the frictional force generated by the contact. Of the three pin insertion holes, one pin insertion hole and the remaining two pins In the insertion hole, the shifting direction is the reverse direction.

  Since this output connector 10A is a connector defined in EIAJ RC-5236 “Latch Lock Type Round Connector for Audio Equipment”, as shown in FIG. 4 (c), the first pin E and the second pin SH , The third pin SC is arranged substantially at each vertex of the isosceles triangle, and the third pin SC is arranged almost in the middle between the first pin E and the second pin SH.

  Therefore, as shown in FIG. 3, the third pin insertion holes 113 are arranged eccentrically with respect to the corresponding third pin SC by at least the difference Δt toward the opposite center side (radially outward) of the connector base 11. On the other hand, the first pin insertion hole 111 and the second pin insertion hole 112 are at least as described above in the direction opposite to the third pin insertion hole 113 with respect to the corresponding first pin E and second pin SH by 180 °. It is preferable to arrange them eccentrically by the difference Δt.

  According to this, since each pin insertion hole 111,112,113 contact | abuts with sufficient balance with respect to each pin E, SH, and SC, the stable fixed state is obtained. In order to make the electrical / mechanical connection more reliable, the pins E, SH, SC and the through-hole plating in the pin insertion holes 111, 112, 113 may be soldered.

  According to the present invention, the inside of the microphone of high-frequency current caused by strong electromagnetic waves radiated from a mobile phone or the like can be obtained by adding the printed wiring board 100 having the above-described configuration without changing the basic configuration of the output connector. Can be reliably prevented from entering. Further, the printed wiring board 100 can be securely attached to the output connector by a simple operation.

The front view which shows an example of the output connector by this invention. AA sectional view taken on the line AA of FIG. The top view of FIG. (A) Top view of printed circuit board, (b) Bottom view of printed circuit board, (c) Plan view of connector base. (A) Explanatory drawing which shows the relationship of the magnitude | size of a pin and a pin insertion hole, (b) Explanatory drawing which shows the state which made the pin insertion hole eccentric with respect to the pin. The equivalent circuit diagram containing the capacitor | condenser element and Zener diode which are provided between each pin of an output connector. Sectional drawing shown in the state which mounted | wore the connector output part with the conventional output connector. The front view which shows the conventional output connector. The top view which shows the conventional output connector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10A Output connector 11 Connector base 11a Base inner surface 12 Fixing male screw 14 Ground terminal board 20 Connector storage part 100 Printed wiring board 101 Board upper surface 102 Board lower surface 111,112,113 Pin insertion hole 120 Shield layer 130 Filter circuit 131 Capacitor element 132 Zener diode element E Pin 1 for grounding SH Pin 2 on the hot side SC Pin 3 on the cold side

Claims (3)

This is a 3-pin type output connector in which a grounding pin 1, a signal pin 2, and a pin 3 are inserted through a connector base made of an electrical insulator. In the output connector of the microphone mounted in a state where the first pin is conducted to the microphone case in the end portion,
A printed wiring board disposed on the inner surface of the base that faces the inside of the microphone case of the connector base through the three pins;
The printed wiring board is a double-sided board, and a copper foil solid on the upper surface of the board opposite to the inner surface of the base is non-conductive with respect to the second and third pins and conductive with the first pin. A shield layer made of a pattern is formed over almost the entire upper surface of the substrate,
A filter circuit including a capacitor element that prevents high-frequency current from entering the microphone case is formed on the lower surface of the substrate facing the base inner surface,
An output connector for a microphone, wherein pin insertion holes formed in the printed wiring board are arranged eccentrically with respect to the corresponding pins.   The first pin insertion hole for the No. 1 pin, the second pin insertion hole for the No. 2 pin, and the third pin insertion hole for the No. 3 pin, which are formed in the printed wiring board, are all the pins. The same diameter hole having a larger diameter than any one of the first to third pin insertion holes, where Δt is the difference between the radius of each pin insertion hole and the radius of each pin. Are arranged eccentrically in the first direction by at least the difference Δt with respect to the corresponding pins, and the remaining two pin insertion holes are second opposite to the first direction for the corresponding pins. The microphone output connector according to claim 1, wherein the microphone output connector is decentered in the direction of at least by the difference Δt.   The third pin insertion hole is eccentrically arranged at least by the difference Δt toward the center side or the anti-center side of the connector base with respect to the corresponding third pin, and the first pin insertion hole and the second pin 3. The pin insertion hole is arranged eccentrically with respect to the corresponding first pin and the second pin by at least the difference Δt in a direction opposite to the third pin insertion hole. A microphone output connector as described in 1.

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