JP2010068287A - Method of manufacturing head case for microphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a head case for a microphone, in which the manufacturing efficiency is enhanced and the size precision, strength and shield effect of the head case are improved by carrying out ultrasonic welding of a connection part of the head case. <P>SOLUTION: The head case includes: a nearly-dome-shaped upper mesh portion 32 and a nearly-cylindrical lower mesh portion 12 disposed with an intermediate stiffening ring 42, made of an easy-processability metal material, interposed between opposed open edges 33 and 14 and having been subjected to corrosion prevention processing; and a neck ring 22 disposed so as to couple a base end opening 13 of the lower mesh portion 12 to a grip body side. The base end opening 13 of the lower mesh portion 12 is united to the neck ring 22 and the open edges 33 and 14 are united to the intermediate stiffening ring 42 each in a plane by ultrasonic welding to form the head case 11 on the whole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for manufacturing a microphone head case.

  The head case of the microphone plays a role of protecting the microphone unit from external stress while taking sound waves into the microphone unit side.

Some head cases have various shapes. For example, some head cases are formed in a spherical shape as shown in FIG.
JP 56-89193 A

  In the microphone head case shown in FIG. 1 of Patent Document 1, the upper mesh portion and the lower mesh portion covering the microphone unit are integrated with each other so as to exhibit a substantially spherical shape via an intermediate ring. The base end opening of the lower mesh portion is fixed to the gripping body side via a neck ring.

  In this case, if the microphone itself is inexpensive, the head case is integrated with a metal upper mesh portion, a synthetic resin intermediate ring, and a metal lower mesh portion using a rubber adhesive. And the base mesh opening of the lower mesh part, the neck ring made of synthetic resin and the metal gripping body are similarly fixed integrally using a rubber adhesive. It was.

  However, the head case manufactured in this way is fragile when the microphone is dropped or shocked. For this reason, the intermediate ring and neck ring are made of a metal material and the members are caulked together. Although bonding by processing or soldering is also performed, there is still a problem that it is inferior in impact resistance.

  For this reason, in recent years, most head cases have been manufactured by joining members together by brazing to ensure sufficient strength.

  In this case, the brazing method includes silver brazing and copper brazing. Among them, silver brazing has an extremely low melting point and is excellent in that it does not dissolve brass, which is the material of the head case. However, since silver is used, there is a problem that the manufacturing cost becomes extremely high. It was.

  In addition, copper brazing has the advantage that the manufacturing cost is low, but since the melting point is high, if the material of the head case is brass with good workability, it will melt at the time of brazing, It was necessary to use a material having a high melting point such as iron.

  FIG. 3 is an explanatory view showing an example of a manufacturing process by copper brazing conventionally performed for the head case 3 (including Patent Document 1) included in the microphone 1 shown in FIG. 4. As described above, the upper mesh portion 4 and the lower mesh portion 5 are first prepared by separately press-molding a net material made of knitted iron wire for rust prevention.

  In this case, when the upper mesh portion 4 and the lower mesh portion 5 are heated at the time of copper brazing, not only the zinc plating is altered by heat and the strength of the brazed portion is lowered, but also the zinc-like skinned shape which has been altered to black. Is left on the surface of the mesh and the appearance is remarkably impaired. Therefore, a pretreatment is performed to dissolve and remove the zinc layer by chemical treatment.

  The upper mesh portion 4 and the lower mesh portion 5 that have been subjected to such pretreatment include an iron intermediate ring 6 that has a substantially H-shaped cross section between the open edges 4a and 5a that are arranged to face each other (b). Are arranged under the positional relationship shown in FIG. A copper brazing material 7 as a solubilizing material is disposed in advance in each of the grooves 6 a and 6 b of the intermediate ring 6.

  Further, the base end opening 5b of the lower mesh portion 5 is disposed in the groove portion 9 of the iron neck ring 8 having a substantially V-shaped cross section based on the positional relationship shown in FIG. The neck ring 8 has a copper brazing material 7 preliminarily disposed in the groove 9 as well as a male screw 2a on the side of the gripping body 2 as shown in FIG. It can be screwed on.

  After the upper mesh portion 4, the intermediate ring 6, the lower mesh portion 5 and the neck ring 8 are assembled as shown in FIG. 3C, the head case 3 is heated and welded in a heating furnace. Integrated as

  The head case 3 integrated in this way is subjected to rust prevention treatment such as plating, and then necessary coating is performed to obtain a final product as shown in (d).

  However, when the head case 3 is manufactured by the conventional method shown in FIG. 3, after the upper mesh portion 4 and the lower mesh portion 5 are formed with a press, it is necessary to dissolve and remove the zinc layer by chemical treatment. In addition, when the zinc layer is removed from the net material, there is a disadvantage that a gap is formed between the strands and the net strength is lowered.

  In addition, the neck ring 8 has a problem in that the dimensions of the female screw 8a are distorted by heating the neck ring 8, and the neck ring 8 cannot be smoothly screwed onto the male screw 2a on the gripping body 2 side.

  Furthermore, the head case 3 manufactured by the conventional method is inferior in the shielding effect because the welded portion with the intermediate ring 6 and the welded portion with the neck ring 8 are formed in a dot shape via the end portion of the strand. There was also a problem.

  In view of the above-mentioned problems of the prior art, the present invention can improve the manufacturing efficiency by connecting the connecting parts in the head case by ultrasonic welding, and has excellent dimensional accuracy, strength and shielding effect. An object of the present invention is to provide a method for manufacturing a microphone head case.

  The present invention has been made in order to achieve the above-mentioned object, and is a substantially dome that has been subjected to a rust prevention treatment and is disposed with an intermediate ring made of an easily processable metal material interposed between opposed open edges. An upper mesh portion and a substantially cylindrical lower mesh portion, and a neck ring made of an easily processable metal material arranged to connect the proximal opening portion side of the lower mesh portion to the gripping body side. The base mesh opening of the lower mesh portion is ultrasonically welded to the neck ring and the open edges are ultrasonically welded to the intermediate ring, respectively, and the whole is integrated as a head case. It is a feature.

  According to the present invention, the upper mesh portion and the lower mesh portion can be ultrasonically welded to the intermediate ring or the neck ring while being subjected to the rust prevention treatment, so that the strength reduction of the mesh portion is ensured. Can be avoided.

  In addition, since the intermediate ring and neck ring are made of an easily processable metal material, they can be processed easily and are not heated at high temperatures during welding. Can be as high as that.

  Furthermore, after welding, it is possible to immediately paint on the mesh portion that has been subjected to rust prevention treatment, so that it is not necessary to apply rust prevention treatment such as plating again, thereby improving workability. it can.

  In addition, since the members are connected to each other by a welded portion having a planar shape, it is possible to obtain an excellent shielding effect by electrically connecting them reliably.

  The method of the present invention includes an upper mesh portion and a lower mesh portion that have been subjected to a rust prevention treatment and are disposed with an intermediate ring made of an easily processable metal material between open edges, and the lower mesh portion. The present invention is applied in a configuration in which a neck ring made of an easily processable metal material for connecting to the base end opening portion side with the gripping body side is used as a constituent member.

  FIG. 1 is an explanatory view showing an example of a process when ultrasonically welding a neck ring for connecting to the grip body 2 side of the microphone 1 as shown in FIG. 4 on the base end opening side of the lower mesh portion. .

  According to the figure, first, from a lower mesh portion 12 formed by press-molding a net material made of galvanized iron wire for rust prevention, and a metal material that can be easily processed such as brass. A neck ring 22 is prepared as shown in FIG.

  In this case, the lower mesh portion 12 is formed to have a substantially cylindrical shape with a proximal end opening 13 on the lower end side and an open edge portion 14 on the upper end side and slightly bulging in a barrel shape.

  The neck ring 22 includes a base portion 23 having an annular shape substantially corresponding to the outer diameter of the base end opening 13 of the lower mesh portion 12, and a rectilinear wall portion 24 extending in the seat height direction inside the base portion 23. And an inclined wall portion 25 extending so as to expand the distal end side in the seat height direction outside the base portion 23.

  That is, the neck ring 22 is formed by securing a groove portion 26 having a substantially V shape between the base portion 23, the rectilinear wall portion 24, and the inclined wall portion 25. Further, a female screw 27 that is screwed into the male screw 2a included in the gripping body 2 shown in FIG.

  And the lower mesh part 12 arrange | positions the base end opening part 13 in the groove part 26 of the neck ring 22, as shown in FIG.1 (b), and is combined.

  After combining the lower mesh portion 12 and the neck ring 22, as shown in FIG. 1 (c), the neck ring 22 has the base portion 23 on the step portion 51a of the lower anvil 51 through the base portion 23. After placing the upper anvil 52, which is the sound electrode side, on the rectilinear wall portion 24, ultrasonic waves are applied while being pressurized by the upper anvil 52.

  As shown in FIG. 1D, the rectilinear wall portion 24 in the neck ring 22 causes the proximal end opening portion 13 of the lower mesh portion 12 to move between the inclined wall portion 25 and the upper anvil 52 side. It is ultrasonically welded in a planar shape that is bent so as to be sandwiched. Such welding is performed over the entire circumference of the neck ring 22.

  Then, the lower mesh portion 12 and the neck ring 22 are integrated as shown in FIG. 1 (e) after locally generating frictional heat using ultrasonic vibration to form a welded portion 29. Then, the lower anvil 51 and the upper anvil 52 are retracted to complete the process.

  FIG. 2 is an explanatory diagram showing a process example when ultrasonic welding of the upper mesh portion 32 to the lower mesh portion 12 side through the intermediate ring 42 after the lower mesh portion 12 and the neck ring 22 are integrated. is there.

  In this case, the upper mesh portion 32 is formed to have a substantially U-shaped dome shape having an opening edge portion 33 having substantially the same diameter as the open edge portion 14 of the lower mesh portion 12 on the lower end side.

  The intermediate ring 42 has an annular base 43 substantially corresponding to the outer diameter of the open edge 33 of the upper mesh portion 32, and extends in a direction perpendicular to the lateral width direction inside the base 43. The inner supporting wall portion 44 provided and the outer supporting wall portion 45 extending outside the base portion 43 and extending in the direction perpendicular to the lateral width direction are formed in a substantially H shape.

  For this reason, the intermediate ring 42 is formed to include the one-side groove portion 46 and the other-side groove portion 47 surrounded by the base portion 43, the inner branch wall portion 44, and the outer branch wall portion 45.

  When ultrasonically welding the upper mesh portion 32 to the lower mesh portion 12 side via the intermediate ring 42, first, a net material made of knitted iron wire knitted for rust prevention is press-molded. The open edge portion 33 of the upper mesh portion 32 and the open edge portion 14 of the lower mesh portion 12 are combined through an intermediate ring 43 made of a metal material that can be easily processed, such as brass.

  That is, by disposing the open edge portion 33 of the upper mesh portion 32 in the one side groove portion 46 of the intermediate ring 42 and the open edge portion 14 of the lower mesh portion 12 in the other side groove portion 47, respectively. Combined.

  After the upper mesh portion 32 and the lower mesh portion 12 are combined via the intermediate ring 42, as shown in FIG. 2A, the whole is laid down, and the lower anvil 61 is moved from the neck ring 22 side. The inner support wall portion 44 of the intermediate ring 42 disposed so as to face the substantially V-shaped groove portion 61a provided on the peripheral surface thereof is supported.

  On the other hand, the upper anvil 61 is disposed in a positional relationship in which the outer support wall portion 45 of the intermediate ring 42 is accommodated in a substantially U-shaped groove portion 63 a provided in the pressure contact portion 63.

  Next, the upper anvil 61 pushes down the inner support wall portion 44 of the intermediate ring 42 that is supported on the lower anvil 61 side to apply ultrasonic waves. At this time, as shown in FIG. 2B, the inner supporting wall portion 44 is welded in a planar shape while being deformed into a shape along the shape of the substantially V-shaped groove portion 61a. Such welding is performed over the entire circumference of the intermediate ring 42.

  Then, the upper mesh portion 32 and the lower mesh portion 12 locally generate frictional heat using ultrasonic vibration to form a welded portion 49, and as shown in FIG. Then, the lower anvil 61 and the upper anvil 62 are retracted to complete the process.

  For this reason, according to the method of the present invention, the upper mesh portion 32 and the lower mesh portion 12 can be ultrasonically welded to the intermediate ring 42 and the neck ring 22 while being subjected to rust prevention treatment. It is possible to reliably avoid the strength reduction of each mesh portion.

  Further, since the intermediate ring 42 and the neck ring 22 are formed using an easily processable metal material such as brass, the intermediate ring 42 and the neck ring 22 can be easily processed and are not heated at a high temperature during welding. Therefore, for example, the dimensional stability can be increased without the internal thread 27 of the neck ring 22 being deformed.

  Furthermore, after welding, since it can be immediately applied to the respective mesh portions of the upper mesh portion 32 and the lower mesh portion 12 that have been subjected to the rust prevention treatment, the rust prevention treatment such as plating is performed again. Can be effectively contributed to the improvement of workability.

  Further, the members such as the upper mesh portion 32 and the intermediate ring 42, the intermediate ring 42 and the lower mesh portion 12, and the lower mesh portion 12 and the neck ring 22 are welded portions 29 and 49 each having a planar shape. Therefore, it is possible to obtain an excellent shielding effect by securely connecting electrically.

Explanatory drawing which shows the process example at the time of ultrasonic-welding a neck ring to the base end opening part side of a lower mesh part as (a)-(e). Explanatory drawing which shows the process example at the time of ultrasonically welding an upper mesh part with the lower mesh part side via an intermediate ring, after integrating a lower mesh part and a neck ring. Explanatory drawing which shows the manufacturing process example by the copper brazing conventionally performed of the head case of a microphone as (a)-(d). Explanatory drawing which shows an example of a microphone provided with a head case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Head case 12 Lower mesh part 13 Base end opening part 14 Open edge part 22 Neck ring 23 Base part 24 Straight advance wall part 25 Inclined wall part 26 Groove part 27 Female thread 29 Welded part 32 Upper mesh part 33 Open edge part 42 Middle ring 43 Base part 44 inner support wall portion 45 outer support wall portion 46 one side groove portion 47 other side groove portion 49 welded portion 51 lower anvil 51a step portion 52 upper anvil 61 lower anvil 61a, 61b groove portion 62 upper anvil 63 pressure contact portion 63a groove portion

Claims (1)

An approximately dome-shaped upper mesh portion and an approximately cylindrical lower mesh portion that have been subjected to a rust prevention treatment and are disposed with an intermediate ring made of an easily processable metal material interposed between the opposed open edges; A neck ring made of an easily processable metal material arranged to connect the base opening part side of the lower mesh part to the grip body side, and the base opening part of the lower mesh part is connected to the neck ring The method for producing a head case of a microphone, wherein each open edge is ultrasonically welded to the intermediate ring in a planar shape and integrated as a head case.

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