JP5518511B2 - Condenser headphone unit - Google Patents

Description

   The present invention relates to a capacitor headphone unit that can prevent the occurrence of spark discharge due to the concentration of an electric field, and can also eliminate the occurrence of noise by eliminating leakage current.

  As disclosed in Patent Document 1, the capacitor headphone unit includes an electroacoustic transducer formed by arranging fixed poles in pairs on both sides of the diaphragm. In this type of condenser headphone unit, a signal voltage for sound reproduction is applied to each fixed pole in a state where a polarization voltage of about 500 V is applied to the diaphragm, thereby vibrating the diaphragm to generate sound. Can be output.

JP 2006-270663 A

  4-6 is explanatory drawing which shows an example of the conventional capacitor | condenser headphone unit containing patent document 1, among which FIG. 4 (a) is a side view by the side of a diaphragm, (b) is the same. FIG. 5A is a front view, FIG. 5A is a side view of the fixed pole on one side of the pair of fixed poles, FIG. 5B is the front view, and FIG. The side view of the capacitor | condenser headphone unit after assembling a pair of fixed pole integrally is shown, (b) shows the principal part enlarged view of (a), respectively.

  According to these figures, the condenser headphone unit 1 includes a diaphragm 2 having a peripheral edge 3a sandwiched between a pair of holding rings 4 and 4 so that a predetermined tension is applied to a circular diaphragm 3. A pair of fixed poles 5 each having a ring-shaped insulating seat 8 attached to a peripheral edge 6a of a fixed pole material 6 made of a perforated plate having a circular shape.

The capacitor headphone unit 1 has a pair of holding rings 4, 4 included in the diaphragm 2 in between, and the fixed pole 5 in a state in which the insulating seat 8 protrudes outward on one side thereof. 2 of the other still an insulation cylinder 8 on the side of the fixed pole 5 in a state of protruding outward are arranged respectively, so as to sandwich the retaining ring 4 side corresponding with the inner surface 8 a of the insulating seat 8 The whole is formed by integrating the diaphragm 2 and the fixed pole 5.

  In this case, since the diaphragm 3 constituting the diaphragm 2 needs to be operated as an electrode for forming a capacitor, it is necessary to impart conductivity.

  In this case, there is a conductive metal vapor deposition method for imparting conductivity to the vibrating membrane 3, but when the vibrating membrane 3 and the fixed electrode material 6 are in mechanical contact, a large amount of current flows and spark discharge occurs. As a result, heat is generated and the vibrating membrane 3 side is destroyed. Further, such a spark discharge is generated not only when the vibrating membrane 3 and the fixed electrode material 6 are mechanically contacted but also between the fixed electrode materials 6 and 6 disposed before and after the vibrating membrane 3. To do. In addition, as a method for imparting conductivity to the vibration film 3, there is a method of applying a surfactant.

  In addition, since the fixed pole material 6 requires an opening through which sound waves are transmitted, a metal plate or a metal net having a large number of sound holes 7 is used.

  By the way, when two fixed pole materials 6 are arranged in parallel and a DC voltage for bias is applied, an electric field is generated such as the end 7a of the sound hole 7 of the fixed pole material 6 or a wire of a metal net. Spark discharge occurs from the concentrated area.

  In such a case, although there is a method of reducing the occurrence of spark discharge by applying a fluororesin coating on the surface of the vibrating membrane 3 or the fixed electrode material 6, the temperature rise due to the spark discharge reaches 1000 degrees Celsius or more. Therefore, when spark discharge is generated between the fixed electrode materials 6 and 6, there is a disadvantage that a large number of microscopic holes are opened in the vibrating membrane 3 and are broken.

  On the other hand, since the fixed electrode material 6 can be given high heat resistance by applying a ceramic coating to the whole, it is possible to prevent discharge between the fixed electrode materials 6 and 6, but the ceramic does not absorb moisture. Therefore, there is a problem that the surface resistance is lowered due to a rise in temperature due to sweating when the headphones are worn on the human head, and noise due to leakage occurs.

  In view of the problems of the prior art including Patent Document 1, the present invention can prevent the breakdown of the diaphragm by eliminating the occurrence of spark discharge due to the concentration of the electric field, and can also prevent the generation of noise by eliminating the leakage current. An object is to provide a condenser headphone unit.

The present invention has been made to achieve the above object, and includes a diaphragm having a peripheral edge sandwiched between a pair of retaining rings so that a predetermined tension is applied to the diaphragm, and a plurality of sound holes. A capacitor headphone unit comprising an insulating seat attached to a peripheral portion of a fixed pole material having a pair of fixed poles disposed so that inner surfaces thereof face each other , and at least the fixed pole is disposed on the inner surface of each fixed pole It includes the inner surface of the material, the corner of the sound hole, and the inner edge of the hole that passes through the corner. These parts are coated with a water-soluble paint-like ceramic to prevent the occurrence of spark discharge due to the concentration of the electric field. The main feature is that it is covered with a ceramic layer formed by heating and curing.

  In this case, a fluororesin coating layer can be further formed on the ceramic layer in order to increase its surface resistance.

  According to the first aspect of the present invention, a ceramic layer is formed on the inner surface side even when a large audio signal is applied to a pair of fixed poles after a biasing DC voltage is applied to the pair of fixed poles. Therefore, it can be used stably by eliminating the occurrence of spark discharge due to the concentration of the electric field and effectively preventing the destruction of the diaphragm side.

Further, the fixed electrode, since the inner surface side including at least the fixed poles through the corner and said corner of the inner surface and the sound hole of the material hole end portion is covered with a ceramic layer, vibration membrane fixed pole Since current does not flow even if it contacts the material side, the diaphragm side can be prevented from being destroyed by heat generation.

  According to the invention according to claim 2, since the fluororesin coating layer is formed on the ceramic layer provided on the inner surface side of each fixed electrode, the humidity resistance and the surface resistance are increased, and the environment is in a high humidity environment. In addition, it is possible to effectively prevent noise due to leakage current.

It is explanatory drawing which illustrates the diaphragm which comprises the capacitor | condenser headphone unit in this invention, Among them, (a) shows a side view, (b) shows the front view, respectively. It is explanatory drawing which illustrated the fixed pole of the one side of a pair of fixed pole which comprises the capacitor | condenser headphone unit in this invention, (a) of which is a side view, (b) is the same front view , (C) is an enlarged view of the main part of (a). Explanatory drawing which expands the principal part and shows the side structure of the capacitor | condenser headphone unit of this invention. It is explanatory drawing which shows the diaphragm which comprises the conventional capacitor | condenser headphone unit, Among them, (a) shows a side view, (b) shows the front view, respectively. It is explanatory drawing which shows the fixed pole of the one side of a pair of fixed pole which comprises the conventional capacitor | condenser headphone unit, (a) of which is a side view, (b) is the front view, respectively. Show. It is explanatory drawing which shows the conventional capacitor | condenser headphone unit after assembling a diaphragm and a fixed pole integrally, (a) is a side view, (b) is the principal part enlarged view of (a), respectively. Show.

  1 to 3, the condenser headphone unit 11 is a diaphragm in which a peripheral portion 13 a is sandwiched between a pair of holding rings 14 and 14 so that a predetermined tension is applied to a circular vibrating membrane 13. 12 and a pair of fixed poles 22 and 22 formed by attaching a ring-shaped insulating seat 26 to the peripheral edge portion 23a of the circular fixed pole material 23.

  Among these, the diaphragm 12 includes a vibration film 13 formed by providing a conductive metal deposition film or a surfactant on a synthetic resin film such as PET (polyethylene terephthalate) or PPS (polyphenylene sulfide), and the vibration. A pair of insulating retaining rings 14, 14 made of, for example, a brass material that sandwiches the peripheral edge portion 13a from both sides under a state of being stretched in the circumferential direction so that a predetermined tension is applied to the film 13. And are formed as shown in FIGS. 1 (a) and 1 (b).

  Each of the fixed poles 22 is attached to a fixed pole material 23 formed by using a metal plate or a metal net having the same structure having a large number of sound holes 24 through which sound passes, and a peripheral portion 23 a of the fixed pole material 23. The ring-shaped insulating seat 26 is formed as shown in FIGS.

In this case, the insulation seat 26, the recess 2 7 thickness of the inner surface 2 8 bottom corner fixed circumferentially located portion electrode material 23 is formed, fixed electrode through the recess 2 7 Material periphery 23a of 23 and an inner surface 2 8 of the inner surface 25 and the insulating seat 26 is adapted to receive positioned so as to be flush.

Further, the fixed electrode 22, the inner surface 22a which includes an inner surface 25 of the fixed electrode material 23 and the inner surface 2 8 of the insulating seat 26, a water-soluble paint-like ceramic (e.g., Ltd. Odekku "Serakoto" etc. The ceramic layer 29 is formed by coating the solvent with a thickness of about 0.1 mm, for example, and then heating and curing it. Since the coating ceramic is water-soluble, the coating thickness can be controlled by the degree of dilution with water and the spray coating conditions.

Moreover, the ceramic layer 29, since the ceramic coating is a water-soluble paint-like, not only the inner surface 2 8 of the inner surface 25 and insulation cylinder 26 of the fixed electrode material 23 at the time of coating, inner side 2 8 2c in a state where it also enters a part of the outer peripheral surface 26a adjacent to the inner peripheral portion 24a and the hole inner end portion 24a including the corner C of the sound hole 24 of the fixed pole material 23, as shown in FIG. Become.

That is, when the inner surface 25 of the fixed pole material 23 is coated with ceramic, the hole inner end 24a including the corner C of the sound hole 24 can also be covered with the ceramic layer 29. High heat resistance can be imparted.

  In this case, more preferably, the ceramic layer 29 of each fixed electrode 22 is coated with a fluorine resin (for example, “Fluorobarrier FP-1054” manufactured by ING Co., Ltd.) to a thickness of 1 μm or less. It is desirable to increase the moisture resistance and surface resistance by forming a fluororesin coating layer, since the coating thickness of the fluororesin is 1 μm or less, so that the fixed electrode 22 is formed. In this case, it is only necessary to manage only the coating thickness of the ceramic.

  The capacitor headphone unit 11 has a pair of holding rings 14 and 14 included in the diaphragm 12 in between, and the insulating seat 26 located on the left side in FIG. Originally, the inner side surface 28 (the inner surface 22a side) on which the ceramic layer 29 is formed is brought into contact with one of the holding rings 14 positioned on the left side in FIG.

In addition, the inner surface 2 8 (on the inner surface 22a side) on which the ceramic layer 29 is formed in a state where the insulating seat 26 located on the other side of the diaphragm 12, that is, the right side in FIG. ) Is brought into contact with the other holding ring 14 located on the right side in FIG.

Capacitor headphone Uni Tsu DOO 11, diaphragm 12 and a pair of so as to sandwich the respective insulating seat 26 provided in the pair of fixed poles 22 and 22 which are arranged parallel to each retaining ring 14 mutually provided in the diaphragm 12 By integrating the fixed poles 22 and 22, the whole is formed under the arrangement relationship shown in FIG.

Next, will be described effects of the present invention configured as described above, a pair of fixed poles 22 and 22 constituting the capacitor headphone uni Tsu DOO 11, each fixed electrode material 23 on its inner surface 2 5 The ceramic layers 29 rich in heat resistance provided can be arranged facing each other.

Therefore, capacitor headphones Uni Tsu DOO 11, after applying a DC voltage for bias the pair of fixed poles 22, 22 are arranged parallel to, it is added a large sound signal (several 100 Vrms) thereto, Since the corner C of the sound hole 24 of the fixed electrode material 23 and the inner end 24a of the sound hole 24 are covered with the ceramic layer 29, unlike the conventional example shown in FIG. Can be reliably prevented.

Thus, the capacitor headphone Uni Tsu DOO 11 may be used to prevent the occurrence of problems that would be destroyed by small holes are drilled in the vibrating membrane 13 by spark discharge stably.

  In addition, since each of the fixed pole materials 23 in each fixed pole 22 includes a ceramic layer 29 on the inner surface 25 facing the diaphragm 13 in the diaphragm 12, the diaphragm 13 is temporarily on the side of the fixed pole material 23. Even if they are in contact with each other, since the ceramic layer 29 is interposed, current does not flow, so that the vibration 12 can be prevented from being broken due to heat generation.

  Further, in the case where a fluororesin coating layer formed by coating fluororesin on the ceramic layer 29 provided on the inner surface 22a side of each fixed electrode 22 is formed, moisture resistance and surface resistance can be increased. Therefore, the generation of noise due to leakage current can be effectively prevented even in a high humidity environment.

11 capacitor headphone unit 12 vibrating plate 13 vibrating film 13a periphery 14 retaining ring 22 fixed pole 22a inner surface 23 fixed pole material 23a periphery 24 sound hole 24a hole end 25 inner surface 26 insulation cylinder 26a outer circumferential surface 27 recess 28 Side 29 Ceramic layer C Corner

Claims (2)

A diaphragm in which the peripheral edge is sandwiched between a pair of retaining rings so that a predetermined tension is applied to the diaphragm, and an insulating seat is attached to the peripheral edge of the fixed pole material having a large number of sound holes. In a condenser headphone unit comprising a pair of fixed poles arranged facing each other,
The inner surface of each fixed pole includes at least an inner surface of the fixed pole material, a corner of the sound hole, and an inner end of the hole through the corner,
A condenser headphone unit characterized in that each of these parts is covered with a ceramic layer formed by coating a water-soluble paint-like ceramic and heating and curing in order to prevent the occurrence of spark discharge due to concentration of an electric field.   The capacitor headphone unit according to claim 1, wherein a fluororesin coating layer is further formed on the ceramic layer to increase its surface resistance.

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