JPH11355081A - Method and device for announcing with controlled noise gain in railroad vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent wiring inside a vehicle from being complicated and to control the gain of a power amplifier at a low frequency corresponding to a noise control signal having satisfactory frequency characteristics at a high frequency by providing a microphone for noise detection in electronic communication emergency alarms installed in respective vehicles. SOLUTION: Noises in the vehicle are detected using the transmission parts of electronic communication emergency alarms provided in respective vehicles, and the gain of the amplifier is controlled by sending that noise signal to the noise gain control circuit of an internal public address amplifier. In the transmission mode of the internal amplifier, the noise gain control circuit is fixed to the gain based on the noise signal just before the transmission and when the transmission is canceled, the gain of the internal amplifier is updated by the current noise signal. Namely, when a voice is inputted from a microphone 2, the voice is outputted from an interior speaker 30 but when it is not transmitting, the microphone 23 of the electronic communication emergency alarm in the same vehicle detects the noise in the car and sends the noise signal to the noise gain control circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to in-vehicle broadcasting in railway vehicles, ships, airplanes, and the like, and more particularly to a noise gain control type broadcasting device for controlling a broadcast volume in accordance with the noise level of vehicles. It is.

[0002]

2. Description of the Related Art As a conventional in-vehicle broadcasting device, for example, a noise control type broadcasting device (Utility Model Registration No. 2515825) as shown in FIGS. 3 to 5 is disclosed. The broadcasting device includes an audio signal generating unit that generates an audio signal to be supplied to a speaker provided in the vehicle, and a gain variable unit that supplies the audio signal to the speaker and controls a gain based on a gain control signal. Gain determining means for generating the gain control signal based on a noise signal input from the speaker, and switching the speaker to one of an output side of the gain varying means and an input side of the gain determining means. Means, and the gain determining means includes a high-pass filter for removing a frequency component of the vibration of the vehicle, the feature of which is that a microphone for noise detection is substituted by switching an in-vehicle speaker to reduce noise. To automatically determine the gain of the gain control circuit.

As a recent broadcasting device, for example, FIG.
A noise control broadcasting device as shown in FIG. 7 has been developed. This broadcasting apparatus detects sound broadcasted by a microphone, a gain control circuit and a speaker in a vehicle by a noise detection microphone, and automatically determines the gain of the gain control circuit.

[0004]

In such a conventional broadcasting apparatus, a microphone for noise detection is required to adjust the gain of the gain control circuit, and the wiring in the vehicle is complicated. In order to solve such problems, a switch for switching between a microphone for noise detection and an in-vehicle speaker is used, and is used as a microphone for noise detection when not broadcasting as a speaker during broadcasting. When an in-vehicle speaker is used in place of a microphone for detecting in-vehicle noise, sensitivity is low in a high frequency range, and a signal in a low frequency range is mainly picked up. As a result, it is not preferable to determine the gain of the gain control circuit based on the unbalanced signal of the high frequency and the low frequency, and the noise in the vehicle includes passenger noise and vibration noise during vehicle operation. Becomes dominant.
This vibration noise has many low-frequency components and low high-frequency components. Therefore, vibration noise is added to the audio signal broadcast from the crew cabin, and the low-frequency is further emphasized in the cabin, and the broadcast sound is clear. Degree worse.

[0005]

SUMMARY OF THE INVENTION The present invention has been developed in order to solve the above-mentioned problems, and comprises an in-vehicle broadcasting mechanism for a vehicle such as a railway and an electronic communication type provided in each vehicle. In a broadcasting method for a vehicle such as a railway including an emergency notification mechanism in the same vehicle, a noise in the vehicle is detected through a microphone built in the electronic communication type emergency notification device, and the in-vehicle broadcast. A broadcast amplifier for a vehicle such as a railway, wherein the broadcast volume is varied by determining the gain of the in-vehicle broadcast amplifier through a noise gain control circuit built in the in-vehicle broadcast amplifier comprising a control amplifier and a power amplifier. The present invention provides a broadcasting method of a noise gain control type, and when the in-vehicle broadcasting amplifier of the noise gain control circuit is in a broadcasting state in the broadcasting method, the gain is fixed to a gain by a noise signal immediately before the broadcasting state. , Whereas the gain of the broadcasting state is released Announcement amplifier is the current noise gain control type of broadcasting methods to be updated by the noise signal.

Further, the present invention provides a vehicle broadcasting device and an electronic communication type emergency notification device in the same vehicle, or a railway device such as a railway vehicle in which the vehicle broadcasting device and the electronic communication type emergency notification device are integrated. , An electronic call type emergency reporter that detects noise in the vehicle via a microphone built in the reporter, an in-vehicle broadcast amplifier including a control amplifier and a power amplifier for in-vehicle broadcasting, and an in-vehicle broadcast amplifier. A noise gain control circuit incorporated therein, wherein the noise gain control circuit determines the gain of the in-vehicle broadcast amplifier to vary the broadcast volume, and a noise control type in a broadcast mechanism for vehicles such as railways. And the noise gain control circuit divides the noise frequency band into a plurality of parts to generate a plurality of control signals, and increases the in-vehicle broadcast by combining the control signals. A noise gain control type broadcasting device for controlling a frequency band of an audio signal of a band-pass filter including a low-pass filter and a high-pass filter incorporated in a device, and while the noise gain control circuit is outputting broadcast audio. This is a noise gain control type broadcasting device that keeps on-vehicle noise information immediately before the broadcast sound is output, and constantly updates the in-vehicle noise information when the broadcast sound is lost. To provide a noise gain control type broadcasting device that operates as a noise detector after the emergency notification is released, when the alarm is activated as a reporter, the gain of the noise gain control circuit is fixed at a specified value and the emergency reporter is operated only as an emergency reporter. is there.

That is, according to the present invention, by using a microphone for noise detection by using a transmission section of an electronic communication type emergency reporter installed in each vehicle, it is possible to eliminate the complexity of wiring in the vehicle and to provide a low frequency band and a high frequency band. The present invention provides an in-vehicle broadcasting method and apparatus for controlling the gain of a power amplifier using a noise control signal having a good frequency characteristic, and enabling a high-clarity broadcast to be heard even in the vibration noise of a running vehicle. It is.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention achieves the above object by detecting noise in a vehicle by using a transmission section of an electronic telephone type emergency reporter provided in each vehicle, and detecting the noise signal. To the noise gain control circuit of the in-vehicle broadcast amplifier to control the gain of the in-vehicle broadcast amplifier. When the in-vehicle broadcast amplifier is in the broadcast state, the noise gain control circuit is fixed to the gain by the noise signal immediately before the broadcast state, but when the broadcast state is released, the gain of the in-vehicle broadcast amplifier becomes the current noise signal. Will be updated. This noise signal is divided into a plurality of frequency bands and divided around 500 Hz, and the in-vehicle broadcast amplifier constitutes a band-pass filter including a high-pass filter and a low-pass filter.
When the following noise signal becomes large, the cutoff frequency of the high-pass filter is made continuous, but it is also possible to gradually change the cutoff frequency to a higher one to gradually cut off the low frequency region. In this case, simply cutting off the low-frequency region degrades the sound balance, so it is necessary to vary the high-frequency cutoff frequency of the low-pass filter.
0 Hz, and the high cutoff frequency is low cutoff frequency (KHz), high cutoff frequency (KHz) =
It can also be a value satisfying 0.7 to 1.5. On the other hand, when the noise above 500Hz becomes loud, increase the gain of the amplifier according to the noise, and when the noise becomes loud over the entire frequency band, adjust both to listen to the broadcast sound with high clarity even in the noise. Can be.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a noise gain control type broadcasting apparatus according to the present invention. As is apparent from this figure, when the broadcast start switch 1 is pressed by the broadcast control amplifier in the crew compartment, the broadcast amplifier of the passenger vehicle is started by the relay 7 via the broadcast start line 5, so that the in-vehicle speaker 30 is connected. Then it will be in a broadcast state. On the other hand, if a sound is input from the broadcast microphone 2, a broadcast sound is output from the in-vehicle speaker 30 of the passenger vehicle. The transmission microphone 23 detects noise in the cabin vehicle, and can transmit the noise signal to the noise gain control circuit. The noise signal is divided into a signal of 500 Hz or more and a signal of 500 Hz or less by a high-pass filter 20 and a low-pass filter 19 incorporated in the noise gain control circuit.
1. The signal is sent to the volume control element 10, low-pass filter element 12, and high-pass filter element 11 of the broadcast power amplifier through the sample-and-hold circuit 22. Further, the volume control element 1
At 0, the sound volume adjusting element 10 is constituted by the photoelectric resistance element 13 and the resistance 14, and is set so that the sound volume increases when the noise signal of 500 Hz or more increases. The high-pass filter 11 includes the photoelectric resistance element 15 and the capacitor 16. When the noise signal of 500 Hz or less increases, the resistance value of the photoelectric resistance element 15 decreases, and 50 Hz to 600 Hz.
And the cutoff frequency is shifted to a higher frequency. Further, the low-pass filter 12 composed of the photoelectric resistance element 17 and the capacitor 18 is set so that the resistance value of the photoelectric resistance element 17 is increased by increasing the noise signal of 500 Hz or less, so that high-frequency components are reduced. Thus, the cutoff frequency becomes lower. In this case, as for the relationship between the low-pass filter 12 and the high-pass filter 11, when the product of the respective cutoff frequencies (KHz) is between 0.7 and 1.5, a well-balanced sound with good intelligibility can be obtained. Further, in the noise gain control circuit, the sample and hold circuit is in a sample state when the broadcast is not activated and constantly updates the signal detecting the noise in the vehicle, and when the broadcast is activated, the noise immediately before the broadcast is activated. Since the signal level is held, the noise signal level is held until the broadcast activation is canceled.

FIG. 2 shows another embodiment of the present invention shown in FIG. First, a broadcast sound and a noise sound are identified by a noise detection microphone 23 by a comparator, and when a broadcast sound is present, a sample and hold circuit is set to a hold circuit state, and when there is no broadcast sound, a sample circuit state is controlled. It is configured. Then, when the emergency report is activated, that is, when the emergency start switch 24 is pressed, the report relay 25 operates and the emergency report microphone 23 is activated.
Is output to the emergency notification voice line 28 by the relay contact 27. At this time, the voltage is fixed to a constant value by the voltage of the constant voltage diode via the noise signal relay contact 28 of the noise gain control circuit.

[0011]

According to the present invention, a broadcasting method for a vehicle such as a railway, in which an in-vehicle broadcasting mechanism for a vehicle such as a railway and an electronic communication type emergency notification mechanism provided in each vehicle are provided in the same vehicle. A noise gain control incorporated in an in-vehicle broadcast amplifier comprising an in-vehicle broadcast control amplifier and a power amplifier, wherein the noise in the vehicle is detected through a microphone incorporated in the electronic communication type emergency report. A noise gain control type broadcasting method in which a gain of an in-vehicle broadcast amplifier is determined through a circuit to vary a broadcast volume. In the broadcast method, when the in-vehicle broadcast amplifier of the noise gain control circuit is in a broadcast state, the broadcast is performed. This is a noise gain control type broadcasting method in which the gain is fixed by the noise signal immediately before the state, and the gain of the in-vehicle broadcast amplifier is updated by the current noise signal when the broadcast state is released. In the conventional method has the advantages did Tokura.

Further, the present invention relates to a broadcasting apparatus for a vehicle such as a railway in which a vehicle broadcasting apparatus and an electronic communication type emergency communication apparatus are provided in the same vehicle. An electronic call type emergency reporter for detecting the noise gain, an in-vehicle broadcast amplifier comprising a control amplifier and an electric power amplifier for in-vehicle broadcasting, and a noise gain control circuit built in the in-vehicle broadcast amplifier, A noise control type broadcasting device in which a control circuit determines a gain of an in-vehicle broadcast amplifier to vary a broadcast volume, and the noise gain control circuit divides a frequency band of noise into a plurality of parts to generate a plurality of control signals. The frequency band of the audio signal of the band-pass filter consisting of the low-pass filter and the high-pass filter built in the in-vehicle broadcast amplifier is controlled by the combination of the control signal and the control signal. A noise gain control type broadcasting device, wherein the noise gain control circuit keeps the in-vehicle noise information immediately before the broadcast audio is output while the broadcast audio is output, while the noise gain control circuit always keeps the noise information when the broadcast audio disappears. A noise gain control type broadcasting device for updating in-vehicle noise information, and when the electronic call type emergency reporter is activated as an emergency reporter, the gain of the noise gain control circuit is fixed to a specified value, and the It is a noise gain control type broadcasting device that operates as a noise detector after the emergency call is released, which only operates as a reporter.Therefore, noise is transmitted using the transmitter of the electronic call type emergency reporter installed in each vehicle. The use of a detection microphone reduces the complexity of wiring in the vehicle, controls the gain of the power amplifier using a noise control signal with good low-frequency frequency characteristics in the low frequency range, and further reduces the vibration noise when the vehicle is running. Also it is possible to provide a vehicle broadcast system configured as hear a highly articulation broadcast in within.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a noise gain control type broadcasting device according to the present invention.

FIG. 2 is a schematic block diagram showing another embodiment of the noise gain control type broadcasting device shown in FIG. 1;

FIG. 3 is a schematic block diagram showing a conventional noise control type broadcasting device.

FIG. 4 is a schematic block diagram showing a conventional noise control type broadcasting device.

FIG. 5 is a schematic block diagram showing a conventional noise control type broadcasting device.

FIG. 6 is a schematic block diagram showing a conventional noise control type broadcasting device.

FIG. 7 is a schematic block diagram showing a conventional noise control type broadcasting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Broadcast start switch 2 Broadcast microphone 3 Broadcast start relay 4 Broadcast start relay contact 5 Broadcast start line 6 Broadcast audio line 7 Broadcast amplifier start relay 8, 9 Broadcast amplifier start relay contact 10 Volume control element 11 High-pass filter element 12 Low pass filter element 13 Volume control photoelectric resistance element 14 Volume control resistance 15 High pass filter photoelectric resistance element 16 High pass filter capacitor 17 Low pass filter photoelectric resistance element 18 Low pass film capacitor 19 Low pass filter 20 High pass filter 21 Rectifier 22 Sample and hold Circuit 23 Emergency call device microphone 24 Emergency call device start switch 25 Emergency call device start relay 26, 27 Emergency call device start relay contact 28 Emergency call sound line 2
9 Emergency call device activation line 30 Broadcast car speaker 31 Microphone for noise detection 32 Level comparator

Claims (6)

[Claims] 1. A broadcasting method for a vehicle such as a railway, comprising an in-vehicle broadcasting mechanism for a vehicle such as a railway and an electronic communication type emergency notification mechanism provided in each vehicle in the same vehicle. Detects noise in the vehicle via a microphone built into the call-type emergency call device, and via a noise gain control circuit built into the in-vehicle broadcast amplifier comprising a control amplifier and a power amplifier for in-vehicle broadcasting. A broadcast method of a noise gain control type in a broadcast mechanism for a vehicle such as a railway, wherein a broadcast volume is varied by determining a gain of an in-vehicle broadcast amplifier. 2. In the broadcast method, when the in-vehicle broadcast amplifier of the noise gain control circuit is in a broadcast state, the gain is fixed by a noise signal immediately before the broadcast state, and when the broadcast state is released, the in-vehicle broadcast amplifier is released. 2. A method according to claim 1, wherein the gain is updated by a current noise signal. 3. In a broadcasting device for a vehicle such as a railway in which a vehicle broadcasting device and an electronic communication type emergency communication device are provided in the same vehicle, noise in the vehicle is detected via a microphone built in a reporting device. An electronic call type emergency reporter, an in-vehicle broadcast amplifier including a control amplifier and a power amplifier for in-vehicle broadcasting, and a noise gain control circuit built in the in-vehicle broadcast amplifier, wherein the noise gain control circuit includes: A broadcast apparatus of a noise control type in a broadcast mechanism for a vehicle such as a railway, wherein a broadcast volume is varied by determining a gain of an in-vehicle broadcast amplifier. 4. The noise gain control circuit divides a noise frequency band into a plurality of parts to generate a plurality of control signals, and combines a low-pass filter and a high-pass filter incorporated in an in-vehicle broadcast amplifier according to a combination of the control signals. The noise gain control type broadcasting apparatus in a broadcasting mechanism for a vehicle such as a railway according to claim 3, wherein the frequency band of the audio signal of the band-pass filter is controlled. 5. The noise gain control circuit keeps the in-vehicle noise information immediately before the broadcast sound is output while the broadcast sound is being output, and constantly updates the in-vehicle noise information when the broadcast sound is lost. A noise gain control type broadcasting device in a broadcasting mechanism for vehicles such as railways according to claim 4. 6. When the electronic call type emergency reporter is started up as an emergency reporter, the gain of the noise gain control circuit is fixed to a specified value, and after the emergency report is released only as an emergency reporter. Operates as a noise detector.
6. A noise gain control type broadcast apparatus in a broadcast mechanism for vehicles such as railways according to 4 and 5.