JP2016191609A - Temperature measuring device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure space temperature using sound waves in an audible range reaching farther than ultrasonic waves.SOLUTION: A temperature measuring device includes: a transmitter 1 for generating sound waves having a predetermined sound wave pattern and an audible range frequency; a receiver 2 for receiving sound waves; and a measurement part 3 for calculating an average temperature of a target space in that the transmitter 1 and the receiver 2 are installed, on the basis of known distance of the transmitter 1 and the receiver 2, and propagation time of the sound waves from the transmitter 1 to the receiver 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a temperature measuring apparatus and method for measuring the temperature of a space with sound waves.

  The speed of the sound wave transmitted through the space changes depending on the temperature of the space (in the living space, it is the temperature of air, which is equivalent to room temperature). Using this property, a technique for measuring the temperature of space by means for generating and receiving sound waves and means for detecting the propagation time of sound waves for a predetermined section in the space is known ( (See Patent Document 1 and Patent Document 2).

JP 2010-139251 A US Pat. No. 5,349,859

  Patent Document 1 discloses a spatial temperature measurement method using ultrasonic waves. However, it is generally known that ultrasonic waves have a smaller energy as they travel farther in the same propagation medium. This characteristic is conspicuous when the propagation medium is a liquid rather than a solid and a gas rather than a liquid. Therefore, the method disclosed in Patent Document 1 has a problem in that the measurement distance is limited when measuring the temperature of a space, particularly a living space.

  Further, as in the technique disclosed in Patent Document 2, an apparatus that performs temperature measurement using acoustic waves (sound waves) in a noisy environment such as a furnace or a boiler is known, but an office, a hospital, or the like. An apparatus for measuring temperature using such an acoustic wave in a human living environment has not been put into practical use.

  The present invention has been made to solve the above-described problem, and a temperature measuring apparatus and method capable of measuring the temperature of a space, particularly a living space, using sound waves in an audible region that reach farther than ultrasonic waves. The purpose is to provide.

The temperature measuring device of the present invention includes a transmitter that generates a sound wave having a predetermined sound wave pattern and an audible region frequency, a receiver that receives the sound wave, a known distance between the transmitter and the receiver, and the transmission And a calculation means for calculating an average temperature of a target space in which the transmitter and the receiver are installed based on a propagation time of the sound wave from the transmitter to the receiver. .
Further, in one configuration example of the temperature measuring device of the present invention, the calculation means is configured to output the transmitter from the transmitter based on a cross-correlation calculation between the sound wave signal transmitted from the transmitter and the sound wave signal received by the receiver. Based on the cross-correlation calculating means for calculating the propagation time of the sound wave to the receiver, the known distance between the transmitter and the receiver, and the calculation result of the cross-correlation calculating means, the sound speed of the target space is calculated. A sound speed calculating means for calculating, and a temperature calculating means for calculating an average temperature of the target space based on a calculation result of the sound speed calculating means.
Further, in one configuration example of the temperature measuring device of the present invention, a plurality of the receivers are installed in the target space, and the calculation means calculates an average temperature of the space between the transmitter and each receiver. The calculation is performed in order.
Moreover, in one structural example of the temperature measuring device of the present invention, the sound wave having the sound wave pattern and the audible region frequency is a chime sound generated at a predetermined period.

  Further, the temperature measurement method of the present invention includes a transmission step of generating a sound wave having a predetermined sound wave pattern and an audible region frequency from a transmitter, a reception step of receiving the sound wave by a receiver, the transmitter and the receiver Calculating a mean temperature of a target space in which the transmitter and the receiver are installed based on a known distance of the transmitter and a propagation time of the sound wave from the transmitter to the receiver. It is characterized by this.

  According to the present invention, the sound wave transmitted from the transmitter is a sound wave signal having a predetermined sound wave pattern and an audible region frequency. Therefore, the temperature of the space can be measured farther than the conventional method of measuring the space temperature using ultrasonic waves. Further, in the present invention, if a sound wave pattern is set so that a person in the target space does not feel uncomfortable, even if a sound wave having an audible frequency is used, the person in the target space feels distrust. There is no unpleasantness caused by the sound and sound that sounds. In addition, if sound wave patterns that can be easily distinguished from indoor environmental sounds, human voices, and external noises entering the room are set, environmental sounds, human voices, external noises, etc. can be easily separated from sound waves. become.

It is a block diagram which shows the structure of the temperature measuring apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart explaining operation | movement of the temperature measurement apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the frequency data of a 7 tone scale. It is a figure which shows the frequency change pattern in a chime sound. It is a top view which shows the example of arrangement | positioning of the transmitter and receiver which are provided in object space. It is a top view which shows another example of arrangement | positioning of the transmitter and receiver which are provided in object space.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a temperature measuring apparatus according to the first embodiment of the present invention. The temperature measuring device includes a transmitter 1, a receiver 2, and a measuring unit 3 (calculation means).

The transmitter 1 that transmits sound waves is constituted by, for example, a speaker. The receiver 2 that receives the sound wave transmitted from the transmitter 1 is configured by, for example, a microphone.
The transmitter 1 and the receiver 2 are spaced apart by a predetermined distance L. For example, in a room, the transmitter 1 is installed on one wall surface and the receiver 2 is installed on the opposite wall surface. By measuring the propagation time until the sound wave transmitted from the transmitter 1 is received by the receiver 2, the propagation time is converted into the indoor average temperature, and the indoor temperature is measured.

  The measurement unit 3 includes a signal output unit 30, a signal input unit 31, a storage unit 32, a cross correlation calculation unit 33, a sound speed calculation unit 34, a temperature calculation unit 35, and an output unit 36. Such a measuring unit 3 includes, for example, an arithmetic device such as a CPU (Central Processing Unit), a storage device such as a memory and an HDD (Hard Disc Drive), an external device such as a keyboard, a mouse, a pointing device, a button, and a touch panel. An input device that detects the input of information from an external device, an interface (I / F) device that transmits and receives information to and from the outside, and a display device such as an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) Consists of a computer. The CPU performs processing as the measurement unit 3 according to a program stored in the storage device.

  Hereinafter, the operation of the temperature measuring apparatus according to the present embodiment will be described with reference to the flowchart of FIG. The signal output unit 30 is an interface circuit that transmits a transmission signal (electric signal) having a predetermined sound wave pattern and audible region frequency to the transmitter 1 and the cross-correlation calculation unit 33. The signal output unit 30 acquires this transmission signal from the storage unit 32. The transmitter 1 generates a sound wave having an audible frequency corresponding to the transmission signal from the signal output unit 30 (step S1 in FIG. 2).

  The receiver 2 receives the sound wave transmitted from the transmitter 1 and converts it into a received signal (electric signal) (step S2 in FIG. 2). The signal input unit 31 is an interface circuit that receives a reception signal from the receiver 2 and inputs the received signal to the cross correlation calculation unit 33.

  Next, the cross-correlation calculating unit 33 calculates the propagation time t of the sound wave from the transmitter 1 to the receiver 2 based on the transmission signal input from the signal output unit 30 and the reception signal input from the signal input unit 31. Calculation is performed (step S3 in FIG. 2). Specifically, the cross-correlation calculating unit 33 sets the reception time at which the cross-correlation function is maximum when calculating the cross-correlation function between the transmission signal and the reception signal as the time t2 when the receiver 2 receives the sound wave. The propagation time t is calculated by taking the difference between the time t1 (the time when the transmission signal is received from the signal output unit 30) when the sound wave corresponding to the transmission signal is transmitted from the device 1 and the time t2 when the sound wave is received. Here, the cross-correlation calculating unit 33 has a time measuring function, and realizes the calculation of the time t1 and the time t2 by receiving the transmission signal and the reception signal in synchronization.

The storage unit 32 stores in advance a transmission signal having a predetermined sound wave pattern and an audible frequency, a distance L between the transmitter 1 and the receiver 2, and the like.
The sound speed calculation unit 34 calculates the sound speed C from the distance L stored in the storage unit 32 and the propagation time t calculated by the cross correlation calculation unit 33 (step S4 in FIG. 2). Specifically, the sound speed calculation unit 34 calculates the sound speed C based on the following equation (1).
C = L / t (1)

The temperature calculation unit 35 calculates the average temperature T of the space between the transmitter 1 and the receiver 2 based on the calculation result by the sound speed calculation unit 34 (step S5 in FIG. 2). When the average temperature T of the space is used, the sound speed C in this space is expressed as the following equation (2). The temperature calculation unit 35 calculates the average temperature T of the space by substituting the sound speed C calculated by the sound speed calculation unit 34 into Equation (2). In the following formula (2), M represents the molecular weight of the gas, κ represents the specific heat ratio, R represents the gas state constant, and these M, κ, and R are known values.
C ² = κRT / M (2)

  The output unit 36 is an interface circuit that outputs a calculation result by the temperature calculation unit 35. The calculation result output from the output unit 36 is displayed on the display screen of the measuring device, transmitted to the outside (for example, an air conditioning control device) via a communication line, or stored in a storage medium. (Step S6 in FIG. 2). The temperature measuring device may periodically perform temperature measurement as in steps S1 to S6.

  As described above, in the present embodiment, the sound wave transmitted from the transmitter 1 is a sound wave signal having a predetermined sound wave pattern and an audible region frequency. Therefore, it is possible to measure the temperature of the space up to a longer distance than the spatial temperature measurement method using ultrasonic waves disclosed in Patent Document 1. In addition, if a sound wave pattern is set so that people in the space will not feel uncomfortable, even if sound waves in the audible area are used, people in the measurement environment may feel distrust or sound Will not be uncomfortable. In addition, if a sound wave pattern that can be easily distinguished from indoor environmental sounds, human voices, and external noises that enter the room is set, it is easier to correlate the transmitted signal and the received signal. Can be easily separated from other voices and external noise.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. This embodiment describes a specific example of the first embodiment. Also in the present embodiment, the configuration of the temperature measurement device and the flow of processing are as described in the first embodiment. The temperature measurement cycle described in the first embodiment may be set as appropriate, and the temperature measurement may be performed while always playing a melody having a predetermined sound wave pattern and frequency, but the temperature measurement is performed according to the predetermined cycle. It is also possible.

  For example, in an office or school, for example, it is conceivable to measure temperature using a chime sound having a predetermined sound wave pattern and frequency. In this way, people in the measurement environment rarely feel a sense of incongruity with the chime sound they hear from everyday. Of course, not only a chime sound but also music may be output from the transmitter 1 during a break to measure the temperature.

  FIG. 3 is a diagram showing the frequencies of sounds included in one octave in the seven-tone scale. FIG. 4 is a diagram showing the scale and frequency of a well-known chime sound. That is, a chime sound is output from the transmitter 1 by changing the scale in a predetermined pattern in the order shown in FIG. By receiving this chime sound by the receiver 2 and performing the arithmetic processing described in the first embodiment, the average temperature T of the space can be measured.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. In the first and second embodiments, an example is shown in which temperature measurement is performed by a pair of transmitter 1 and receiver 2 installed on the wall surface of the target space. As shown in the plan view of FIG. 5, when one transmitter 1 and one receiver 2 are arranged on the wall surface of the target space 10, the average temperature of the space between the transmitter 1 and the receiver 2 is measured. It is possible. That is, this average temperature can be regarded as the room temperature of the target space 10.

  On the other hand, when acquiring the detailed temperature distribution information of the object space 10, what is necessary is just to arrange | position the several receivers 2-1 to 2-6 in the object space 10, as shown in FIG. In this case, the average temperature of the space is measured between the transmitter 1 and the receiver 2-1 by the method described in the first embodiment, and between the transmitter 1 and the receiver 2-2. What is necessary is just to measure the average temperature of space between the transmitter 1 and each receiver 2-1 to 2-6 like measuring the average temperature of space. Thus, the temperature distribution of the target space 10 can be measured.

  The present invention can be applied to a technique for measuring the temperature of a space.

  DESCRIPTION OF SYMBOLS 1 ... Transmitter, 22-1 to 2-6 ... Receiver, 3 ... Measurement part, 30 ... Signal output part, 31 ... Signal input part, 32 ... Memory | storage part, 33 ... Cross correlation calculation part, 34 ... Sound velocity Calculation unit, 35 ... temperature calculation unit, 36 ... output unit.

Claims (8)

A transmitter for generating sound waves having a predetermined sound wave pattern and audible range frequency;
A receiver for receiving the sound wave;
Based on the known distance between the transmitter and the receiver and the propagation time of the sound wave from the transmitter to the receiver, the average temperature of the target space in which the transmitter and the receiver are installed is calculated. A temperature measuring device comprising a calculating means for calculating. The temperature measuring device according to claim 1,
The computing means is
Based on the cross-correlation calculation between the sound wave signal transmitted from the transmitter and the sound wave signal received by the receiver, cross-correlation calculation means for calculating the propagation time of the sound wave from the transmitter to the receiver;
Based on a known distance between the transmitter and the receiver, and a calculation result of the cross-correlation calculation unit, a sound speed calculation unit that calculates a sound speed of the target space;
A temperature measuring device comprising temperature calculating means for calculating an average temperature of the target space based on a calculation result of the sound speed calculating means. The temperature measuring device according to claim 1 or 2,
A plurality of the receivers are installed in the target space,
The temperature measuring device characterized in that the calculation means calculates an average temperature of the space in order between the transmitter and each receiver. In the temperature measuring device according to any one of claims 1 to 3,
The temperature measuring device, wherein the sound wave having the sound wave pattern and the audible region frequency is a chime sound generated at a predetermined period. Transmitting a sound wave having a predetermined sound wave pattern and an audible region frequency from the transmitter; and
A receiving step of receiving the sound wave by a receiver;
Based on the known distance between the transmitter and the receiver and the propagation time of the sound wave from the transmitter to the receiver, the average temperature of the target space in which the transmitter and the receiver are installed is calculated. A temperature measurement method comprising: a calculation step for calculating. The temperature measuring method according to claim 5, wherein
The calculation step includes:
A cross-correlation calculation step for calculating a propagation time of the sound wave from the transmitter to the receiver based on a cross-correlation calculation between the sound wave signal transmitted from the transmitter and the sound wave signal received by the receiver;
Based on the known distance between the transmitter and the receiver and the calculation result of the cross-correlation calculation step, a sound speed calculation step for calculating the sound speed of the target space;
And a temperature calculating step of calculating an average temperature of the target space based on a calculation result of the sound speed calculating step. The temperature measuring method according to claim 5 or 6,
A plurality of the receivers are installed in the target space,
The calculating step is characterized in that an average temperature in space is calculated in order between the transmitter and each receiver. The temperature measurement method according to any one of claims 5 to 7,
The temperature measurement method, wherein the sound wave having the sound wave pattern and the audible region frequency is a chime sound generated at a predetermined period.

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