JP2008147806A - Condenser microphone and manufacturing method thereof - Google Patents

Abstract

The present invention provides a condenser microphone in which an input terminal of an impedance converter is soldered to a fixed pole side by completely removing agglomerated flux causing leakage current, and a method of manufacturing the same.
A soldering process for soldering a gate terminal 16 of an FET 13 as an impedance converter 12 to a fixed pole 42 side is pretreated by covering the remaining part of the soldering part 17 with an insulating sealing material S and curing it. And the actual soldering process for soldering the soldering part 17 and the post-treatment for removing the agglomerated flux 20 adhering to the insulating sealing material S side after the soldering. It is possible to provide the condenser microphone 11 that is completely removed and prevents generation of noise due to leakage current.
[Selection] Figure 1

Description

  The present invention relates to a condenser microphone manufactured by soldering an input terminal of an impedance converter to a fixed pole side, and a technique related to a manufacturing method thereof.

  The capacitor microphone includes at least an impedance converter that can input a signal voltage change of a capacitor portion formed by arranging a diaphragm and a fixed pole in a high impedance state, and can output the change in a low impedance state. Is formed.

  For example, a field effect transistor (hereinafter referred to as “FET”) having a gate terminal as an input side terminal and a vacuum tube having a grid terminal as an input side terminal are used in a capacitor microphone as an impedance converter.

Among these, when the impedance converter is an FET, for example, as disclosed in FIG. 2 of Patent Document 1 below, the gate terminal is connected to a relay member such as a contact spring interposed between the fixed pole and the gate terminal. Some of them are in contact with each other to ensure conduction with the fixed pole side. In addition, in such an FET, the gate terminal may be soldered to a contact spring on the fixed pole side in order to strengthen conduction between the FET and the fixed pole side.
JP 2006-157332 A

Further, a condenser microphone that requires particularly good sound quality uses a vacuum tube as disclosed in Patent Document 2 below as an impedance converter. In this case, the vacuum tube as an impedance converter has a grid terminal soldered to the fixed pole side.
Japanese Patent Laid-Open No. 11-317996

  FIG. 3 is a side view showing a conventional soldering state of the gate terminal with respect to the fixed pole side when an FET is used as the impedance converter. According to the figure, the FET 1 mounted on the printed circuit board 5 includes a gate terminal 3 drawn from the side surface of the main body 2 and directed toward the fixed pole 7 side, and a drain terminal and a source terminal directed toward the printed circuit board 5 side. And at least a lead terminal 4 drawn out as a pair (the other one is hidden in the illustrated example).

  Among these, the gate terminal 3 is pulled out from the side surface side of the main body 2, folded back to the side facing the fixed electrode 7, and soldered to the contact spring 6 interposed between the FET 1 and the fixed electrode 7. It is attached.

  In this case, the gate terminal 3 is routed with a predetermined distance from the main body 2 in order to avoid the occurrence of leakage current. For this reason, a narrow gap G is generated between the side surface of the main body 2 and the gate terminal 3.

  In the capacitor microphone manufactured by soldering in this way, the FET 1 is fixed to the fixed electrode by performing a soldering process in which the soldering portion 3a of the gate terminal 3 is soldered to the fixed electrode 7 side via the contact spring 6. 7 is manufactured with a structure for inputting the signal voltage from the 7 side with high impedance.

  By the way, as shown in FIG. 3, the flux 9 used for improving the familiarity of the solder 8 is provided on the peripheral side of the soldering portion 3 a where the gate terminal 3 is connected to the contact spring 6 via the solder 8. Aggregates and the flux 9 adheres to a part including the gap G around the soldering part 3a.

  Since the flux 9 attached in this manner has a property of absorbing moisture with time and increasing the electrical conductivity, the insulation of the soldering part 3a is weakened. For this reason, normally, the flux 9 is dissolved with a solvent or detergent, and then washed and removed using a brush or the like.

  However, the FET 1 shown in FIG. 3 is difficult to remove because the flux 9 that has entered and adhered to the gap G between the main body 2 and the gate terminal 3 does not enter the gap G with the brush tip of the cleaning brush. In other words, it is incorporated into a condenser microphone as a product as it is left. For this reason, the capacitor microphone has a problem in that the insulation property of the soldered portion 3a of the FET 1 is reduced and a leakage current is generated, so that the FET 1 cannot maintain a high input impedance and generates noise. .

  Even when a micro vacuum tube is used as the impedance converter, such a problem occurs similarly because the flux 9 is left in a narrow portion when the grid terminal is soldered. .

  In addition, such problems do not occur at the initial stage when they are commercialized as condenser microphones, but occur after a certain amount of time has passed since the user started using them, thus deteriorating the product image. There was also a problem.

  In view of the above-mentioned problems of the prior art, the present invention provides a signal voltage input side terminal (a gate terminal in the former case, a grid terminal in the latter case) for a FET or vacuum tube used as an impedance converter in a condenser microphone. Another object of the present invention is to provide a condenser microphone and a method of manufacturing the same that can completely eliminate the agglomerated flux that causes leakage current and solder it to prevent the noise caused by the agglomerated flux.

  The present invention has been made to achieve the above object, and a first invention (a method of manufacturing a condenser microphone) includes an input terminal of an impedance converter that receives a signal voltage from the fixed pole side with high impedance. In the method of manufacturing a condenser microphone including at least a soldering step of soldering the fixed side to the fixed pole side, the soldering step includes soldering the input-side terminal drawn toward the fixed pole side. A pre-treatment for covering and hardening the remaining part except the part with an insulating sealing material without gaps, an actual soldering process for soldering the soldering part, and an agglomerated flux adhering to the insulating sealing material side after the soldering The main feature is that it is carried out through post-treatment to remove the.

  In this case, it is desirable that the input side terminal is either a gate terminal in the FET or a grid terminal in the vacuum tube.

  In addition, the second invention (condenser microphone unit) is characterized by being manufactured by the manufacturing method according to claim 1 or 2.

  According to the invention of claim 1, the soldering step of the input side terminal of the impedance converter with respect to the fixed pole side is performed before the remaining part of the input side terminal except the soldered part is covered with the insulating sealing material without a gap and cured. Since it is performed through a process, an actual soldering process that solders the soldering part, and a post-process that removes the agglomerated flux adhering to the insulating sealing material after soldering, leakage current from the input side terminal A condenser microphone can be manufactured by completely removing the causative aggregated flux and soldering the input side terminal to the fixed pole side.

  According to the invention of claim 2, it is possible to manufacture a condenser microphone that does not generate a leakage current from the input side terminal, regardless of whether an FET or a vacuum tube is used as the impedance converter. .

  Furthermore, according to the invention of claim 3, the condenser microphone manufactured by the above manufacturing method can prevent generation of noise due to leakage current from the input side terminal of the impedance converter, and can be comfortably for a long time. Will be able to use.

  FIG. 1 is an explanatory view showing the soldering process when the impedance converter is an FET in the first invention of the present invention, according to the processing procedure, of which (a) is pre-processing, and (b) is The actual soldering process is shown in FIG. FIG. 2 is a side view showing the positional relationship between the FET and the printed circuit board before entering the soldering process.

  In this case, as is apparent from FIG. 2, the FET 13 is pulled out from the main body 14 including a gate electrode, a source electrode, and a drain electrode (not shown), and from the side surface 14a of the main body 14 toward the fixed pole 42. It has a gate terminal 16 as the input side terminal 15 and a lead terminal 18 formed of a pair of a source terminal and a drain terminal which is similarly drawn out from the side surface 14a and soldered to the printed circuit board 22. In the illustrated example, since one of the source terminal and the drain terminal is hidden behind, only one lead terminal 18 is shown.

 Among these, the gate terminal 16 includes a lead portion 16a that protrudes from the side surface 14a side of the main body portion 14, an upright portion 16b that is directly raised from the lead portion 16a along the surface direction of the side surface 14a, and the upright portion 16b. As shown in FIG. 1 (b), it is formed of a folded portion 16c that is used as a soldering portion 17 so as to face the surface 14b of the main body portion 14 facing the fixed pole 42. .

  For this reason, the gate terminal 16 is routed with a narrow gap G interposed between the upright portion 16 b and the side surface 14 a of the main body portion 14.

  Next, an example of the soldering process of soldering the gate terminal 16 of the FET 13 having such an arrangement relationship to the fixed pole 42 side will be described. The gate terminal 16 drawn toward the fixed pole 42 side will be described. Cover the remaining part except the soldering part 17 with the insulating sealing material S without a gap and harden it, and solder the soldering part 17 to the contact spring 32 used as an intervening part on the fixed pole 42 side. It is performed through a soldering process and a post-process for removing the agglomerated flux 20 adhering to the insulating sealing material S after soldering.

  Among these, the pretreatment includes the lead portion 16a and the upright portion which are the remaining portions of the soldering portion 17 of the gate terminal 16 so as to close the gap G formed between the side surface 14a of the main body portion 14 and the upright portion 16b. 16b is covered with an insulating sealing material S and cured.

  In this case, as the insulating sealing material S, for example, a one-part room temperature curable silicone rubber such as a product number KE347 manufactured by Shin-Etsu Chemical Co., Ltd. can be suitably used.

  Next, the actual soldering process to be performed is performed between the fixed electrode 42 and the EFT 13 by using, as the soldering portion 17, the folded portion 16 c side that is turned back to the surface 14 b facing the fixed electrode 42 in the main body 14. It is performed by soldering to the intervening contact spring 32 side.

  In this case, the contact spring 32 includes a base part 33 attached to the main body part 14 through the facing surface 14b side, and a spring plate part 34 extending inward from the side edge side of the base part 33. And is formed so as to be freely press-contacted to the fixed pole 42 side through the spring plate portion 34.

  The folded portion 16c of the gate terminal 16 is integrally soldered with the solder 19 as a soldering portion 17 to a portion of the base portion 33 of the contact spring 32 that is located on the opposite surface 14b side of the main body portion 14. Has been.

  In this case, the flux component contained in the solder 19 itself to improve the familiarity or a separately prepared flux is an insulating sealing cured as an aggregated flux 20 on the peripheral side of the soldering portion 17 during soldering. It adheres to the surface side of the material S.

  The post-treatment is performed to clean and remove such agglomerated flux 20 adhering to the surface of the insulating sealing material S.

  The gate terminal 15 as the input-side terminal 15 passes through the soldering process including the pretreatment, the actual soldering treatment, and the posttreatment, so that the soldering portion 17 is connected to the base portion 33 of the contact spring 32. By soldering to the fixed pole 42 side, it is possible to form a reliable conductive relationship with the fixed pole 42 side via the spring plate portion 34.

  That is, the remaining part of the gate terminal 16 except for the folded portion 16c (soldering part 17) is a gap between the gate terminal 16 and the side face 14a due to the insulating sealing material S having fluidity after the pretreatment. It will be completely covered including G. Moreover, since the one-component room temperature curable silicone rubber or the like is used for the insulating sealing material S, it can be cured after application.

  Since the actual soldering process is performed after such a pretreatment, even if the agglomerated flux 20 is generated during soldering, it only adheres to the surface of the cured insulating sealing material S, and the gap G Adhering to the inside can be surely avoided.

  Therefore, the agglomerated flux 20 adhering to the insulating sealing material S after soldering can be easily and completely removed by, for example, dissolving it with a solvent in a post-treatment and washing it with a brush.

  The condenser microphone 11 whose principal part is shown in FIG. 1 (c) is impedance-transformed with respect to the fixed pole 42 side without leaving the aggregated flux 20 that causes leakage current in the gap G in this way. The gate terminal 16 included in the FET 13 as the container 12 is soldered and manufactured.

  Further, even when a micro tube (not shown) is used as the impedance converter 12 for the condenser microphone 11, an input without aggregating flux adhering to a narrow part can be achieved through a processing procedure similar to that for the FET 13. A grid terminal as the terminal 15 can be soldered.

  Therefore, the capacitor microphone 11 manufactured by the above manufacturing method maintains the high input impedance by allowing the FET 13 or the vacuum tube as the impedance converter 12 to ensure the insulation of the soldered portion 17 of the input side terminal 15. Also, it is possible to reliably prevent the generation of noise due to the leakage current.

  For this reason, the user can comfortably use the condenser microphone 11 manufactured by the above manufacturing method for a long period of time.

  The above is the description of the present invention based on the illustrated example, and the specific configuration is not limited thereto. For example, the FET 13 used as the impedance converter 12 has a gate terminal 16 formed by a lead portion 16a, an upright portion 16b, and a folded portion 16c. However, the FET 13 is formed by the lead portion 16a and the upright portion 16b. The upright portion 16 b can be used as the soldering portion 17. Further, the gate terminal 16 is not limited to being drawn from the side surface 14 a side of the main body portion 14, but can be formed by the upright portion 16 b and the folded portion 16 c drawn from the facing surface 14 b side to the fixed pole 42.

It is explanatory drawing which shows the soldering process in case the impedance converter is FET in 1st invention among this invention according to a process sequence, (a) is pre-processing, (b) is real solder (C) shows post-processing. The side view which shows the arrangement | positioning relationship between FET and a printed circuit board. The side view which shows the conventional soldering condition of the gate terminal with respect to the fixed pole side at the time of using FET as an impedance converter.

Explanation of symbols

11 Condenser microphone 12 Impedance converter 13 Field effect transistor (FET)
DESCRIPTION OF SYMBOLS 14 Main-body part 14a Side surface 14b Opposite surface 15 Input side terminal 16 Gate terminal 16a Lead-out part 16b Upright part 16c Folding part 17 Soldering part 18 Lead terminal 19 Solder 20 Aggregation flux 22 Printed circuit board 32 Contact spring 33 Base part 34 Spring board part 42 Fixed pole G Gap S Insulating sealing material

Claims (3)

In a method of manufacturing a condenser microphone, including at least a soldering step of soldering an input side terminal of an impedance converter that receives a signal voltage from a fixed pole side with high impedance to the fixed pole side,
The soldering step includes a pre-treatment in which a remaining portion excluding the soldering portion of the input-side terminal drawn out toward the fixed pole side is covered with an insulating sealing material without a gap, and the soldering portion is soldered. A method of manufacturing a condenser microphone, which is performed through an actual soldering process to be applied and a post-process to remove the flux adhering to the insulating sealing material side after the soldering.   The method of manufacturing a condenser microphone according to claim 1, wherein the input side terminal is one of a gate terminal in a field effect transistor and a grid terminal in a vacuum tube.   A condenser microphone manufactured by the manufacturing method according to claim 1.

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