JP2009188491A - Goose neck type microphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably prevent malfunction due to reflection light from a pedestal surface in a goose neck type microphone where a proximity sensor including an infrared-receiving/emitting element is installed near the pedestal surface. <P>SOLUTION: In the goose neck type microphone, the proximity sensor is provided at a base casing 10 installed on the pedestal T, such as a desk, with a microphone unit supported via a flexible support pipe, the proximity sensor includes an infrared-emitting element 121 for emitting infrared rays toward a talker side and an infrared-receiving element 131 for receiving reflection light from the talker side, and a microphone output section is turned on or off by an output signal from that proximity sensor. In the goose neck type microphone, a light shielding section 175 for shielding reflection light from the pedestal surface Ts in infrared rays emitted from the infrared-emitting element 121 is formed at one portion of an opening 173 for receiving light where the infrared-receiving element is disposed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gooseneck type microphone, and more particularly to a gooseneck type microphone having a function of controlling on / off of a microphone output by a proximity sensor.

  One type of microphone is a microphone with a built-in proximity sensor. In this microphone, the presence or absence of a person (speaker) is detected by a proximity sensor, the microphone output is turned on when a person is detected, and the microphone output is turned off when no person is detected.

  As an example, it is used in a church without a microphone operator. In other words, when a gooseneck microphone is set on the church podium and the minister is on the podium to preach the teaching, the microphone output is turned on by the human sensor signal of the proximity sensor. When you are away from, turn off the microphone output so that the choir song is not loud.

  Most of the gooseneck type microphones are condenser microphones, and a phantom power source is generally used as the power source. Since the phantom power supply has a low current supply capability, the proximity sensor is required to consume less power.

  Therefore, in the invention described in Patent Document 1, a pyroelectric infrared sensor using the pyroelectric characteristics of the pyroelectric material is used as the proximity sensor. In the invention described in Patent Document 2, a combination of an infrared light emitting element (for example, an infrared light emitting diode) and an infrared light receiving element (for example, a photodiode) is used for the proximity sensor. Apart from this, an ultrasonic sensor is also known as one of proximity sensors.

  A pyroelectric infrared sensor has the advantage of low power consumption because it does not need to emit infrared light by itself, but it does not detect a person in a stationary state where the person (speaker) does not move, so the microphone output May suddenly stop, which is not preferable as a proximity sensor for a microphone.

  In addition, when using an infrared light emitting element and an infrared light receiving element, the light emitting method of the infrared light emitting element (infrared light emitting diode) includes DC lighting and AC lighting. However, AC lighting suppresses heat generation of the light emitting diode. Can emit strong infrared rays.

  However, if there is an environment where sunlight or other external light enters, or there is a plasma display or the like that generates infrared harmonics in the vicinity, there is a risk of causing malfunctions. It is necessary to use an optical filter in combination. This type of optical filter is quite expensive.

  An ultrasonic sensor consumes a large amount of power and diffracts a sound wave by surrounding objects, so that the detection reliability is low and it cannot be applied to a microphone.

  Therefore, the present applicant has disclosed, as Patent Document 3, an infrared light receiving element that outputs a light reception signal tuned only to a specific frequency, as the proximity sensor, in a microphone that controls on / off of a microphone output unit using an output signal of a proximity sensor. And using an infrared light emitting element that emits infrared light at a tuning frequency of the infrared light receiving element.

  According to the invention described in Patent Document 3, the presence of a person (speaker) is reliably detected by eliminating the influence of disturbance light without using a special optical filter or the like on the light incident side of the infrared light receiving element. can do.

JP 2004-72559 A US Pat. No. 5,818,949 JP-A-2005-311418

  However, in the case of a gooseneck type microphone, the proximity sensor is provided in a base housing (also referred to as an audio output unit or a power module unit) installed on a base such as a desk. Further, the irradiation intensity of the infrared light emitting element is set to be high so that the speaker can be detected even when the speaker is relatively far away.

  As described above, in the gooseneck type microphone, the proximity sensor is arranged near the base surface, and the irradiation intensity of the infrared light emitting element is set high, so that the reflected light on the base surface is picked up by the light receiving element. There is a problem of causing malfunction.

  This problem occurs remarkably when the base surface is finished to be a smooth and reflective surface, for example. In order to prevent this, it is only necessary to make the base surface black, for example, so that reflection is difficult to occur, but it is not only troublesome to install the microphone, but also the distrust of the performance of the microphone is realistic. Is not a good solution.

  Accordingly, an object of the present invention is to reliably prevent malfunction due to reflected light from a base surface with a simple configuration in a gooseneck microphone in which a proximity sensor including an infrared light receiving and emitting element is installed near a base surface such as a desk. It is in.

  In order to solve the above-mentioned problem, the invention according to claim 1 is provided with a base casing that has a microphone output section and is installed on a base such as a desk, and a flexibility that allows a lower end side to be connected to the base casing. And a microphone unit that is attached to the upper end side of the support pipe and that is electrically connected to the microphone output unit via a microphone cord that is inserted into the support pipe. A proximity sensor including an infrared light emitting element that emits infrared light toward a speaker side existing in the vicinity of the base and an infrared light receiving element that receives reflected light from the speaker side is provided, In the gooseneck type microphone that controls on / off of the microphone output unit according to the output signal of the proximity sensor, the infrared light receiving element is disposed in the light receiving opening of the base casing, and the light receiving opening. The portion of the parts, is characterized in that the light shielding unit that shields the reflected light from the base surface of the infrared rays emitted from the infrared light-emitting element is formed.

  According to a second aspect of the present invention, in the gooseneck type microphone according to the first aspect, the infrared light receiving element is disposed in the light receiving opening so that the optical axis thereof is substantially parallel to the base surface. The light-shielding portion is disposed in a portion of the light-receiving opening below the optical axis of the infrared light-receiving element.

  According to a third aspect of the present invention, in the gooseneck type microphone according to the first or second aspect, both the infrared light emitting element and the infrared light receiving element have a light emitting opening and the light receiving opening. The light-shielding portion that is attached to a predetermined part of the base housing in a state of being disposed in the holder and covers a part of the light-receiving opening is formed integrally with the holder.

  The invention according to claim 1, wherein a light-shielding portion that shields reflected light from the base surface of the infrared light emitted from the infrared light-emitting element is formed in a part of the light-receiving opening where the infrared light-receiving element is disposed. Accordingly, it is possible to reliably prevent malfunction due to reflected light from the base surface with a simple configuration.

  The infrared light receiving element is disposed in the light receiving opening so that the optical axis thereof is substantially parallel to the base surface, and the light shielding part is disposed below the optical axis of the infrared light receiving element in the light receiving opening. According to the second aspect of the present invention, the light shielding portion can be easily designed. In addition, in order to enable detection even when the speaker is relatively far away, the reflected light from the base surface can be effectively shielded even if the irradiation intensity of the infrared light emitting element is set high.

  In addition, the infrared light emitting element and the infrared light receiving element are both mounted in a predetermined portion of the base housing in a state where the infrared light emitting element and the infrared light receiving element are disposed in the same holder having the light emitting opening and the light receiving opening, According to the invention of claim 3, wherein the light shielding portion to be covered is formed integrally with the holder, the infrared light emitting element and the infrared light receiving element can be handled as an integrated sensor unit with each directional axis fixed. Therefore, the present invention can also be applied to gooseneck type microphones of different types such as product dimensions. That is, versatility can be given to the proximity sensor.

  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.

  As shown in the front view vertical cross-sectional view of FIG. 1A and the side view vertical cross-sectional view of FIG. 1B, the gooseneck microphone according to the embodiment of the present invention is on a base T such as a podium or a desk. Is provided with a cylindrical base casing 10 installed substantially vertically. A speaker (person) H shown in FIG. 4 is present on the front side of the paper in FIG. 1A and on the right side of the base housing 10 in FIG. 1B when the microphone is used.

  In this embodiment, as shown in FIG. 2, the base housing 10 is fitted into a mounting hole whose lower end is formed in the base T via a rubber elastic body 11 as a vibration absorber. Apart from this, for example, a receiving bracket (not shown) may be provided on the base T, and the base housing 10 may be detachably attached to the receiving bracket.

  Since the base casing 10 is required to have an effect of shielding built-in components from external electromagnetic waves, the base casing 10 is preferably made of a metal material such as brass.

  The lower end of a flexible support pipe 20 including a flexible shaft 21 and a spacer-like relay pipe 22 is fixed to the upper end of the base housing 10. The flexible shaft 21 and the relay pipe 22 are both made of metal, and the support pipe 20 and the base housing 10 are electrically connected.

  A microphone unit 30 is attached to the upper end of the support pipe 20. The microphone unit 30 is roughly classified into an electrodynamic type (dynamic type) and an electrostatic type (condenser type). In a gooseneck type microphone, a condenser type microphone unit is usually used. The power source is often a phantom power source.

  Referring also to the enlarged sectional view of FIG. 2, the base housing 10 includes an output connector 110 to which a cable from the phantom power source is connected at the lower end side. The output connector 110 is preferably a 3-pin connector defined by EIAJ RC-5236 “Latch Lock Type Round Connector for Audio Equipment”. A base 111 to which the support pipe 20 is connected is provided on the upper end side of the base housing 10.

  An infrared transmission unit 120 and an infrared light reception unit 130 that constitute a proximity sensor are provided on the front surface (surface directed toward the speaker side) of the base housing 10 illustrated in FIG. An operation display lamp 140 is also provided, but the operation display lamp 140 may be, for example, a red or green light-emitting diode that is lit when a power switch (not shown) is turned on.

  In this embodiment, the infrared transmission unit 120 includes two infrared light emitting diodes 121 and 122. The optical axes of the infrared light emitting diodes 121 and 122 are oriented substantially parallel to the base surface Ts of the base T. However, in order to widen the detection area of the sensor, each optical axis faces the front side on the speaker side. It is preferable to incline within a range of 45 ° (especially within 30 °) with respect to the center line. The number of infrared light emitting diodes may be one or three or more.

  In this embodiment, the infrared light receiving unit 130 uses a tunable infrared light receiving element (for example, a photodiode) 131 that outputs a light reception signal in synchronization with a specific frequency of incident infrared light. An example of this type of infrared light receiving element is an optical remote control light receiving module part number PIC-3704TM2 / 3724TM2 manufactured by KODENSHI.

  According to the light receiving module, the tuning frequency can be selected from 40.0 KHz, 36.7 KHz, 37.9 KHz, 32.7 KHz, and 56.9 KHz.

  FIG. 3 shows a schematic circuit configuration of the infrared transmitter 120 and the infrared receiver 130. On the infrared transmitter 120 side, two infrared light emitting diodes 121 and 122 are connected in series between the power supply Vcc (+5.5 V in this example) in the base housing 10 and the ground together with a semiconductor switch 124 such as an FET. ing.

  Further, the infrared transmitter 120 is provided with an oscillator 125 that turns on and off the semiconductor switch 124 at high speed. Therefore, the infrared light emitting diodes 121 and 122 are lit at the oscillation frequency of the oscillator 125 to emit infrared rays, and the frequency is matched with the tuning frequency (for example, 37.9 KHz) of the infrared light receiving element 131.

  On the infrared light receiving unit 130 side, a signal holding circuit 132 that holds a light reception signal output from the infrared light receiving element 131 is provided. The signal holding circuit 132 gives an output on signal to the microphone output unit 151 while the light receiving signal is output from the infrared light receiving element 131, and gives an output off signal to the microphone output unit 151 when the light receiving signal is interrupted.

  Although not shown in detail, the microphone output unit 151 is provided on the first circuit board 150 disposed in the base housing 10. For example, the microphone output unit 151 is an audio signal processing circuit formed on the first circuit board 150. It may be an output on / off switch included on the output side.

  The microphone unit 30 is electrically connected to the audio signal processing circuit through a microphone cord (not shown) inserted into the support pipe 20. In addition, an infrared output changeover switch 151 and a sound quality changeover switch 152 are mounted on the first circuit board 150.

  As described above, assuming that infrared rays are radiated from the infrared light emitting diodes 121 and 122 of the infrared transmission unit 120 at a frequency of, for example, 37.9 KHz, the speaker H is present in the detection area in front of the microphone as shown in FIG. If present, a part of the infrared light reflected by the speaker H enters the infrared light receiving element 131.

  As a result, a light reception signal is output from the infrared light receiving element 131 to the signal holding circuit 132, and an output ON signal is given from the signal holding circuit 132 to the microphone output unit 151. Via an external receiver (not shown).

  On the other hand, when there is no speaker H in the detection area in front of the microphone, infrared light having a tuning frequency of 37.9 KHz is not incident on the infrared light receiving element 131, so that a light reception signal is received from the infrared light receiving element 131. The microphone output is turned off without being output.

  However, when the microphone is installed in a small area and there is a reflector such as a wall near the front side of the base housing 10, the microphone output is reflected by the reflected light from the reflector even when there is no speaker H. May turn on.

  In order to prevent such erroneous detection, for example, a variable resistor 123 for adjusting the diode driving current is connected between the power supply Vcc and the infrared light emitting diode 121 as shown in FIG. It is preferable that the intensity of the emitted infrared light can be adjusted, that is, the effective range of the detection area can be adjusted.

  As another cause of false detection, in the gooseneck type microphone, since the proximity sensor is provided in the base housing 10 and is disposed near the base surface Ts, the reflected light on the base surface Ts is reflected by the infrared light receiving element 131. In some cases. This erroneous detection due to reflected light cannot be eliminated by setting the light emitting side and the light receiving side to the tuning frequencies.

  Therefore, in the present invention, a light shielding portion 175 that shields reflected light from the base surface Ts out of infrared light emitted from the infrared light emitting diodes 121 and 122 is formed in a part of the light receiving opening 173 in which the infrared light receiving element 131 is disposed. By forming, malfunction due to reflected light from the base surface Ts is surely prevented.

  The configuration will be specifically described below. In this embodiment, as shown in FIG. 2, the infrared light emitting diodes 121 and 122 and the infrared light receiving element 131 included in the proximity sensor are mounted on the second circuit board 160 in the base housing 10 together with the operation display lamp 140. As an integrated sensor unit, the sensor unit is mounted in a predetermined portion on the front side of the base housing 10 in a state of being disposed in the holder 170.

  In order to explain the configuration of the holder 170, FIG. 4A shows a front view of the holder 170, FIG. 4B shows a rear view of the holder 170, and FIG. 4C shows an A- of FIG. A line sectional view is shown. The holder 170 may be made of either synthetic resin or metal, but is preferably made of metal from the viewpoint of shielding properties against external electromagnetic waves.

  As shown in these drawings, the holder 170 has light emitting openings 171 and 172 in which the infrared light emitting diodes 121 and 122 are disposed, a light receiving opening 173 in which the infrared light receiving element 131 is disposed, and an operation display. An operation display opening 174 in which the operation lamp 140 is disposed is provided. Further, the holder 170 is provided with three holes 176 for screwing the second circuit board 160 in this example.

  The light emitting openings 171 and 172 and the light receiving opening 173 are all round holes, and the infrared light emitting diodes 121 and 122 and the infrared light receiving element 131 have their optical axes substantially parallel to the base surface Ts in these openings. Although arranged, a light shielding portion 175 for shielding the reflected light from the base surface Ts is provided in a part of the light receiving opening 173.

  The light shielding portion 175 is disposed in a portion below the optical axis of the infrared light receiving element 131 in the light receiving opening 173. The light-shielding part 175 may be a separate member from the holder 170, such as a tape base material or a plate material, but is preferably formed integrally with the holder 170 from the viewpoint of reliability and assembly workability.

  Thus, by providing the light-receiving opening 173 with the light-shielding portion 175 that shields the reflected light from the base surface Ts, sufficient reflected light can be obtained even from a speaker far away from the microphone side. Even if the light emission intensity of the infrared light emitting diodes 121 and 122 is set high, it is possible to reliably prevent malfunction due to the reflected light from the base surface Ts.

  In addition, the infrared light emitting diodes 121 and 122 and the infrared light receiving element 131 are disposed in the same holder 170, and a light shielding portion 175 is integrally provided in a part of the light receiving opening 173 to form an integrated sensor unit. Therefore, stable operation can be ensured.

  In the above embodiment, the light receiving opening 173 is formed in the holder 170 attached to the base housing 10. However, the base housing 10 and the holder 170 are integrated, and the light receiving opening is formed in the base housing 10. An embodiment in which 173 is provided is also included in the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS (a) Front view longitudinal cross-section which shows the gooseneck type microphone which concerns on embodiment of this invention, (b) Side view longitudinal cross-section. The expanded sectional view which shows the base housing | casing of the said gooseneck type microphone. The schematic diagram which shows the circuit structure of the infrared rays transmission part and infrared rays reception part in the said gooseneck type | mold microphone. The (a) front view which shows the holder in the said gooseneck type | mold microphone, (b) Rear view, (c) AA sectional view taken on the line.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Base housing | casing 110 Output connector 120 Infrared transmission part 121,122 Infrared light emitting diode 124 Semiconductor switch 125 Oscillator 130 Infrared receiving part 131 Infrared light receiving element 132 Signal holding circuit 151 Microphone output part 170 Holder 171, 172 Light emission opening 173 For light reception Opening 175 Shading part 20 Support pipe 30 Microphone unit

Claims (3)

A base housing that has a microphone output unit and is installed on a base such as a desk, a flexible support pipe whose lower end is connected to the base housing, and a support that is attached to the upper end of the support pipe A microphone unit electrically connected to the microphone output unit via a microphone cord inserted into the pipe, and infrared rays toward the speaker side existing in the vicinity of the base on the base housing A proximity sensor including an infrared light emitting element that emits light and an infrared light receiving element that receives reflected light from the speaker side. In the microphone,
The infrared light receiving element is disposed in a light receiving opening of the base housing, and a part of the light receiving opening shields reflected light from the base surface out of infrared light emitted from the infrared light emitting element. A gooseneck type microphone characterized in that a light shielding part is formed.   The infrared light receiving element is disposed in the light receiving opening so that an optical axis thereof is substantially parallel to the base surface, and the light shielding part is light of the infrared light receiving element in the light receiving opening. The gooseneck microphone according to claim 1, wherein the gooseneck microphone is formed in a portion below the shaft.   Both the infrared light emitting element and the infrared light receiving element are mounted on a predetermined portion of the base casing in a state where the infrared light emitting element and the infrared light receiving element are disposed in the same holder having a light emitting opening and the light receiving opening. The gooseneck type microphone according to claim 1, wherein the light shielding part covering a part of the part is formed integrally with the holder.

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