JP6255213B2 - Gooseneck microphone - Google Patents

Description

  The present invention relates to a gooseneck microphone in which a microphone unit is supported by a flexible shaft that can be bent and has a self-holding property. More specifically, the present invention relates to a technique for preventing corrosion (electric corrosion) of a flexible shaft.

  A gooseneck microphone is a microphone that has a support pipe consisting partly or entirely of a flexible shaft, with a microphone unit supported at the tip, and an audio signal output part attached to the lower end. Since the direction of the microphone unit can be freely changed so as to be close to each other, it is often used in conference halls.

  For example, as described in Patent Document 1, the flexible shaft is sandwiched between a round steel wire made of a steel material having a circular cross section formed in a tension coil spring shape and a round steel wire on the outer peripheral side of the round steel wire. A triangular wire made of, for example, a brass alloy having a triangular cross section wound in such a manner, self-holding property is exhibited by a strong frictional engagement force generated between the round steel wire and the triangular wire.

  However, there is a problem that the steel wire is corroded (also referred to as galvanic corrosion) due to the contact of the steel wire and the brass alloy with different metals. This corrosion progresses with time, and rust powder is generated.The rust powder falls in the support pipe as the flexible shaft is bent, and enters the audio signal output section provided on the lower end side of the pipe. An electrical failure may occur due to the cause.

  Apart from this, there is also a problem that the frictional force between the round steel wire and the triangular wire decreases due to corrosion, and the holding force of the flexible shaft decreases.

  Therefore, in the invention described in Patent Document 1, it has been proposed to suppress the generation of rust powder by applying a rust preventive material to the inner peripheral surface of the flexible shaft.

  However, when the inner diameter of the flexible shaft is small, it is difficult to form a rust preventive film on the inner peripheral surface, and even if a rust preventive film can be formed, the flexible shaft peels off due to bending of the flexible shaft, etc. There is a problem.

Japanese Patent No. 4476838

  Accordingly, an object of the present invention is to provide a gooseneck microphone that can easily and reliably prevent corrosion of a steel wire due to contact of dissimilar metals on a flexible shaft.

In order to solve the above-described problems, the present invention provides a round steel wire made of a steel material having a circular cross section formed in a tension coil spring shape and wound so as to be sandwiched between the round steel wires on the outer peripheral side of the round steel wire. A support pipe including a flexible shaft made of a triangular wire having a triangular cross section, a microphone unit is supported on the front end side of the support pipe, and an audio signal output unit is mounted on the rear end side of the support pipe In the gooseneck microphone in which the microphone unit and the audio signal output unit are electrically connected by a microphone cable inserted into the support pipe,
The microphone cable, and almost a two-core shielded coated wire braided shield is exposed over the entire length, on the shield braid, upper determined steel wire steel material ionization tendency than that including top large metal determined A sacrificial electrode for the steel wire is provided.

  From the viewpoint of workability, the sacrificial electrode is preferably made of a coating film containing a metal powder having a greater ionization tendency than the steel material of the round steel wire in a predetermined binder.

Further, in another aspect of the present invention, a round steel wire made of a steel material having a circular cross section formed in a tension coil spring shape is wound, and wound around the round steel wire so as to be sandwiched between the round steel wires. A support pipe including a flexible shaft made of a triangular wire having a triangular cross section, a microphone unit is supported on the front end side of the support pipe, and an audio signal output unit is mounted on the rear end side of the support pipe A gooseneck microphone in which the microphone unit and the audio signal output unit are electrically connected by a microphone cable inserted into the support pipe, the sacrificial electrode for the round steel wire, and the sacrificial electrode The electrode consists of a coating film containing a metal powder having a greater ionization tendency than the steel material of the round steel wire in a predetermined binder. The coating film is also included gooseneck microphone, characterized in that it is formed along the round steel wire is exposed to the inner surface of the flexible shaft.

  According to the present invention, a sacrificial electrode including a metal (a metal that is easier to emit electrons than iron) having a higher ionization tendency than the steel material of the round steel wire in the flexible shaft is provided in the support pipe that supports the microphone unit. As a result, the sacrificial electrode is corroded earlier (electric corrosion) than the round steel wire, so that corrosion of the round steel wire due to the contact of different metal between the round steel wire and the triangular wire can be prevented with high reliability. it can.

  In addition, a two-core shielded wire is used for the microphone cable. By removing the outer skin over almost the entire length of the microphone cable to expose the shield braid and providing a sacrificial electrode on the shield braid, the microphone cable is placed in the support pipe. The sacrificial electrode can be arranged with respect to the round steel wire of the flexible shaft by a simple operation that only needs to be inserted.

1 is a cross-sectional view illustrating an entire gooseneck microphone according to an embodiment of the present invention. The expanded partial sectional view which shows the 1st aspect which provides a sacrificial electrode in the flexible shaft with which the said gooseneck microphone is provided. The expanded fragmentary sectional view which shows the 2nd aspect which provides a sacrificial electrode in the flexible shaft with which the said gooseneck microphone is provided. The perspective view which shows the microphone cable preferably employ | adopted by this invention.

  Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 4, but the present invention is not limited to this.

  First, referring to FIG. 1, in the gooseneck microphone 1 according to this embodiment, the microphone unit 2 is supported at the front end (upper end) of the support pipe 3, and at the rear end (lower end) of the support pipe 3, An audio signal output unit 4 is attached.

  The microphone unit 2 may be a condenser microphone unit. Although not shown, a microphone capsule including a diaphragm and a fixed pole that are arranged to face each other with a predetermined interval is housed therein.

  The audio signal output unit 4 is also called an output module unit, and includes a cylindrical shield case 41 made of a metal material such as a brass alloy or aluminum. The audio signal output unit 4 is erected on a base such as a table (not shown) via a predetermined fixing bracket.

  The shield case 41 houses a circuit board 42 having an audio signal amplification circuit, a low cut circuit, and the like, and an output connector 43 connected to a phantom power source. The output connector 43 may be a three-pole connector defined in EIAJ RC-5236 “Latch Lock Round Connector for Audio Equipment”.

  The circuit board 42 is electrically connected to the microphone unit 2 via the microphone cable 21 inserted into the support pipe 3. The circuit board 42 is also electrically connected to the output connector 43.

  The support pipe 3 includes a flexible shaft 31 that allows the speaker to freely change the direction of the microphone unit 2. In this embodiment, the flexible shaft 31 includes an upper flexible shaft 31 a on the microphone unit 2 side and the flexible shaft 31. The lower flexible shaft 31b on the audio signal output unit 4 side is coaxially connected by an intermediate straight pipe 32 made of a metal material. Note that the entire support pipe 3 may be configured by the flexible shaft 31.

  Referring to FIG. 2, flexible shaft 31 (31 a, 31 b) includes a round steel wire 34 made of a steel material having a circular cross section formed in a tension coil spring shape, and a round steel wire 34 on the outer peripheral side of round steel wire 34. It is composed of a triangular wire 35 made of a metal having a triangular cross section (brass alloy in this embodiment) that is tightly wound so as to be sandwiched between them, and is free to bend and has a frictional force between the round steel wire 34 and the triangular wire 35. It has a self-holding property that keeps it bent.

  Referring to FIG. 4, the microphone cable 21 is a two-core shielded wire, and a mesh-like shield braid covering the power supply line 23 a and the signal line 23 b inserted into the inner sheath 22 and the entire outer peripheral surface of the inner sheath 22. 24.

  A cable having a shield braid is not limited to a microphone cable, and usually the shield braid is covered with an outer sheath (outer skin) over the entire length of the cable. In this embodiment, the outer sheath is removed and the microphone cable is removed. The shield braid 24 is used in an exposed state over almost the entire length of 21.

  As described above, since the round steel wire 34 and the triangular wire 35 included in the flexible shaft 31 are dissimilar metals (steel material and brass alloy), the round steel wire 34 is corroded (also called electrolytic corrosion). ).

  In order to solve this problem, in the present invention, a sacrificial electrode including a metal having a higher ionization tendency than the steel material of the round steel wire 34 (a metal that emits electrons more easily than iron) is provided in the support pipe 3. This has a first aspect and a second aspect.

  First, in the first embodiment, as shown in FIG. 2, the sacrificial electrode 5, preferably made of zinc, is formed on the shield braid 24 of the microphone cable 21. In forming the sacrificial electrode 5, a coating agent containing zinc powder (zinc particles) in a predetermined binder may be used.

  Examples of this type of coating agent include a rust preventive zinc spray manufactured by Nippe Home Products (material: zinc powder paint “Jinky” manufactured by Nippon Paint Rust Co., Ltd.).

  Thus, by forming the sacrificial electrode 5 made of the zinc coating film on the shield braid 24 of the microphone cable 21, the corrosion of the sacrificial electrode 5 proceeds before the round steel wire 34. As a result, the round steel Corrosion of the wire 34 can be prevented.

  Further, by forming the sacrificial electrode 5 on the shield braid 24, the electrical connection between the sacrificial electrode 5 and the round steel wire 34 is ensured. Furthermore, by using the above coating agent, the sacrificial electrode 5 made of a zinc coating film can be easily formed on the shield braid 24 of the microphone cable 21, and the zinc coating film is flexible. Therefore, even when the flexible shaft 31 is bent, the zinc particles do not fall off.

  Next, as a second aspect, as shown in FIG. 3, the sacrificial electrode 5 for the round steel wire 34 may be formed along the round steel wire 34 exposed on the inner surface of the flexible shaft 31. . Also in this case, the sacrificial electrode 5 containing zinc particles can be easily formed by using the coating agent. 2 and 3, the shield braid 24 shows a state covering the outer peripheral surface of the inner sheath 22.

  Since the round steel wire 34 and the sacrificial electrode 5 only need to be electrically connected, as another aspect, for example, the sacrificial electrode 5 is provided on the outer surface or the inner surface of the shield case 41 of the audio signal output unit 4. The sacrificial electrode 5 may be electrically connected to the round steel wire 34 through a conductive member such as a lead wire.

DESCRIPTION OF SYMBOLS 1 Gooseneck microphone 2 Microphone unit 21 Microphone cable 24 Shield braiding 3 Support pipe 31 (31a, 31b) Flexible shaft 32 Intermediate pipe 34 Round steel wire 35 Triangle wire 4 Audio signal output part 41 Shield case 42 Circuit board 43 Output connector 5 Sacrificial electrode

Claims (3)

A round steel wire made of a steel material having a circular cross section formed in a tension coil spring shape, and a triangular wire having a triangular cross section made of metal and wound around the round steel wire on the outer peripheral side of the round steel wire. A support pipe including a flexible shaft comprising: a microphone unit supported on a front end side of the support pipe, and an audio signal output unit mounted on a rear end side of the support pipe, the microphone unit and the audio signal output In the gooseneck microphone that is electrically connected with a microphone cable inserted through the support pipe,
The microphone cable, and almost a two-core shielded coated wire braided shield is exposed over the entire length, on the shield braid, upper determined steel wire steel material ionization tendency than that including top large metal determined A gooseneck microphone comprising a sacrificial electrode for a steel wire. The gooseneck microphone according to claim 1, wherein the sacrificial electrode is formed of a coating film containing a metal powder having a higher ionization tendency than a steel material of the round steel wire in a predetermined binder. A round steel wire made of a steel material having a circular cross section formed in a tension coil spring shape, and a triangular wire having a triangular cross section made of metal and wound around the round steel wire on the outer peripheral side of the round steel wire. A support pipe including a flexible shaft comprising: a microphone unit supported on a front end side of the support pipe, and an audio signal output unit mounted on a rear end side of the support pipe, the microphone unit and the audio signal output In the gooseneck microphone that is electrically connected with a microphone cable inserted through the support pipe,
The sacrificial electrode is provided with a sacrificial electrode for the round steel wire, and the sacrificial electrode is formed of a coating film containing a metal powder having a greater ionization tendency than a steel material of the round steel wire in a predetermined binder, and the coating film is an inner surface of the flexible shaft. A gooseneck microphone, characterized in that the gooseneck microphone is formed along the round steel wire exposed to the surface.

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