JPS60256049A - Freezing forecast device - Google Patents

Abstract

PURPOSE:To detect the freezing of water in a water feed and drain pipe by utilizing a sonic wave propagation characteristic, by providing a metal container having heat dissipating fins provided to the outer periphery thereof in integral relation to the water feed and drain pipe and arranging an ultrasonic transmitter and an ultrasonic receiver so as to hold the metal container and the water feed and drain pipe therebetween. CONSTITUTION:A cylindrical metal container 3 having heat dissipating fins 2 is integrally attached to the wall surface of a water feed and drain pipe 4 so as to be communicated with said pipe 4 and an ultrasonic transmitter 1 is arranged to one end of the metal container 3 and an ultrasonic receiver 5 is arranged to the inner wall of the water feed and drain pipe 4 so as to be opposed to the transmitter 1. In this constitution, the internal space 6 of the metal container 3 functions as a water sump part and receives the reduced effect of the stream of water in the water feed and drain pipe 4 and cooled by the heat dissipating fins 2 and the water in the internal space 6 is frozen before the water in the water feed and drain pipe 4 is frozen. This freezing phenomenon is detected from the change in a sonic wave propagation characteristic.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a freeze predictor using an ultrasonic transmitter/receiver that operates based on a change in acoustic characteristics accompanying a phase change from liquid to solid.

[Prior art]

Conventionally, in equipment that supplies water during the winter, there has been a method of determining freezing based on the temperature as a means of obtaining information about freezing in advance.

However, water flows and stops in the water supply and drainage pipes.
It was not always possible to obtain accurate freezing information at below freezing temperatures. Furthermore, countermeasures against freezing are also manual and have the problem of not being able to take appropriate action.

[Summary of the invention]

This invention was made in order to improve the above-mentioned problems, and includes a metal container that has heat dissipation fins on the outer periphery and is integrally provided so as to communicate with a water supply and drainage pipe, and this metal container and By installing an ultrasonic transmitter/receiver that faces each other across the water supply and drainage pipes, freezing phenomena can be accurately detected and predicted in advance by utilizing the characteristics of sonic waves, and reported using electrical signals. This paper proposes a freeze predictor that can

[Embodiments of the invention]

FIG. 1 is a sectional view showing a freeze predictor according to an embodiment of the present invention, FIG. 2 is a sectional view of a metal container, FIG. 3 is a plan view thereof, and FIG. 4 is a sectional view of an ultrasonic transmitter/receiver. Figure 5 is (A)
6(C) are explanatory diagrams of usage conditions, and FIGS. 6(A) to 6(C) are output waveform diagrams.

In the figure, (1) is an ultrasonic transmitter, and heat dissipation fins (2)
) is arranged at one end of a cylindrical metal container (3). The metal container (3) is integrally attached to the wall surface of the water supply pipe (4) so as to communicate therewith. The ultrasonic receiver (5) is arranged on the inner wall of the water supply and drainage pipe (4) on a concentric axis so as to face the transmitter (]). The inner diameter of the cylindrical metal container (3) is smaller than the inner diameter of the water supply and drainage pipe (4).

As shown in Figure 4, the configuration of the ultrasonic transmitter/receiver (1) and (5) is as shown in Fig. 4. , a vibrator configured by pasting a piezoelectric element (9) and a metal resonator (10), and a protrusion (
]1), and the open end (12) is hermetically sealed with a lid (14) having an electrical signal input/output terminal (13). The transmitter (1) is fixed to the metal container (3) by a threaded part (15) provided on the outer periphery of the closed end (8), and the receiver (5) is fixed to the inner wall of the water supply and drainage pipe (4). The detection surface is exposed and the screw is fixed.

The ultrasonic transmitter/receiver (1), (5) as described above has the following characteristics: the thickness of the piezoelectric element (9), the thickness of the metal resonator (10), the thickness of the wall of the closed end (8), and the thickness of the protrusion (11). The frequency (resonance) of the sound wave output by the transmitter (1) is determined from the total height, and the moat used vibrates in the longitudinal direction.

The protrusion (11) also has the effect of amplifying the transmission output.

In the freeze predictor configured as described above, the internal space (6) of the metal container (3) with a small inner diameter becomes a water retention area, and the influence of the water flow in the water supply and drainage pipe (4) is also reduced. few. The interior space (6) is intensively and rapidly cooled by the outside air by the radiation fins (2), and the water in the interior space (6) is frozen before the water in the water supply and drainage pipe (4) is frozen. In this way, when there is no flow of water in the water supply and drainage pipe (4), the heat dissipation fins (2
), the dimensions of the internal space (6), that is, the inner diameter of the metal container (3) shall be designed. In this case, when water is constantly flowing in the water supply and drainage pipe (4), the time margin of the freeze predictor differs depending on the flow velocity. And if trees are not washed away, it is easier to predict freezing.

Normally, when the temperature is high and there is no risk of freezing, the interior space (6) of the metal container (3) and the water supply and drainage pipe (4) do not freeze, as shown in Figure 5 (A), and the transmitter (1) The output v1 of the receiver (5) which receives the sound pressure sent into the water is as shown in FIG. 6(A). At sub-zero temperatures, the internal space (6), which serves as a reservoir for water, is replaced by heat dissipation fins (
Due to the heat dissipation effect of 2), the water starts to freeze earlier than the inside of the water supply and drainage '1' (4), as shown in Figure 5 CB). The ice in the internal space (6) acts as a load on the transmitter (1), and the sound waves propagate through the solid and liquid phases, increasing the propagation loss, and as shown in Figure 6 (B), the receiver ( The sound pressure detected by 5) decreases, and the output (2) of the receiver (5) also decreases. When the temperature further drops and the flow of water in the water supply and drainage pipe (4) stops, the interior of the water supply and drainage pipe (4) also freezes. As a result, as shown in Figure 5 (C), only the same phase (ice) exists between the transmitter and receiver (1) and (5), and as shown in Figure 6 (C), the propagation loss decreases and the sound The pressure increases and the output v3 of the receiver (5) increases. Comparing the propagation loss in the liquid phase and the solid phase, the former is larger, so the sound pressure received by the receiver (5) is larger in the latter, indicating the relationship V 3 > V + > V 2 .

By using this information, it is possible to predict freezing in the water supply and drainage pipe (4) and detect the freezing phenomenon.

Note that in the above descriptions, the shapes, structures, etc. of the radiation fins (2) and the metal container (3) are not limited.

Moreover, the metal container (3) may be provided on both sides of the water supply and drainage pipe (4).

〔Effect of the invention〕

According to this invention, since the ultrasonic transmitter/receiver is provided across the metal container having radiation fins and the water supply/drainage pipe, the following effects can be obtained.

■ Since a piezoelectric element is used as an ultrasonic transmitter/receiver, it is possible to electrically predict freezing inside water supply and drainage pipes.

■ It is possible to create a system in which electrical detection is performed.

■ Rapid freezing occurs due to the heat dissipation effect of the heat dissipation fins, making it possible to accurately and quickly predict freezing of water supply and drainage pipes.

■ Lightweight and easy to handle.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a freeze predictor according to an embodiment of the present invention, FIG. 2 is a sectional view of a metal container, FIG. 3 is a plan view thereof, and FIG. 4 is a sectional view of an ultrasonic transmitter/receiver. Figure 5 is (A)
- (C) are explanatory diagrams of usage conditions, and Figs. 6 (^) - (C) are output waveform diagrams. In each figure, the same reference numerals indicate the same parts, (1) is the ultrasonic transmitter, (2) is the heat radiation fin, (3) is the metal container, (4) is the
) is the water supply and drainage pipe, (5) is the ultrasonic receiver, and (7) is the outer cylinder. (9) is a piezoelectric element, (10) is a metal resonator, (14)
) is the lid. Figure 1 Figure 2 Figure 3 Figure 4 Figure 1 Figure 6 Figure 5 (A) (B) (C)

Claims (3)

[Claims] (1) Outer periphery b'' = A metal container that has radiation fins and is integrally provided so as to communicate with the water supply and drainage pipe, and a superstructure that is provided to face the metal container and the water supply and drainage pipe in between. A freeze predictor characterized by comprising a sonic wave transmitter/receiver.7 (2) The freeze predictor according to claim 1, wherein the metal container has an inner diameter tJ+ smaller than that of the water supply and drainage pipe. (3) The ultrasonic transmitter/receiver includes an outer cylinder housing a piezoelectric element;
a protrusion protruding from the outer surface of the outer cylinder on the detection side; a piezoelectric element and a metal resonator provided on the inner surface of the outer cylinder on the detection side;
Claim 1, further comprising: a lid having an electrical signal input/output terminal that seals the opposite side of the outer cylinder.
Freeze predictor according to item 1 or 2.