JPH0452474A - Controlling method for operation of chilled water device - Google Patents

Abstract

PURPOSE:To obtain a method of controlling operation of a chilled water device which can deal with water temperature of cryogenic temperature range or an abnormal operation when water is extremely small by providing a lower temperature sensor at the outer wall of the bottom of a tank of the device or its vicinity and an upper temperature sensor above a cooler, measuring water temperatures of upper and lower parts in the tank at each predetermined time, and controlling ON, OFF of a compressor by the output of a controller when their temperature difference falls within a set range. CONSTITUTION:A lower temperature sensor 18a detects a water temperature in the bottom of a tank, an upper temperature sensor 18b detects a water temperature near the partition of the tank, and the temperatures are output from a sensor circuit 18c to a controller 11 through an A/D converter 19. The measured results of the water temperatures in the lower and upper parts of a tank 2 to be input from the converter 19 at each predetermined time are obtained. After the temperature in the bottom of the tank reaches a set temperature, the temperature in the bottom of the tank is compared with the temperature near the lower half and upper parts of the tank, and when a temperature difference DELTAt1 become a previously programed predetermined value or lower, the energization of a compressor 7 through a driving circuit 23 is turned OFF. if it exceeds a measured temperature difference DELTAt2, the temperature of the compressor 7 is again started. Thus, the temperatures of the upper and lower positions of the tank are measured, and the operation can be controlled by the mutual relation.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for controlling the operation of a tabletop water cooler.

[Conventional technology]

As shown in Figures 4 and 5, a tabletop water cooler has a tank (2
), and the top opening of the tank (2) is covered with the exterior (1).
It was covered with a lid (3) located on the top surface.

In addition, the tank (2) has a lower half (2a) formed with a smaller diameter than the upper half, and a tank holding plate (6) that is hung horizontally within the exterior (1) below this narrow diameter part. Tank fixing plate on top (
15) is erected, and the upper half of the tank (2) is supported from below by the upper part of this tank fixing plate (15).

Furthermore, in the exterior (1), below the tank (2) is a space as a machine room, where a compressor (7) and a fan (9) are installed.
A condenser (8) is installed on the back side of the exterior (1).

A cooler (4) is wound around the lower half (2a) (7) of this tank (2), the surroundings are covered with a heat insulating material (16), and water is injected to communicate with the bottom of the tank (2). pipe (5)
is guided out of the exterior (1) and an operating lever (13
) was combined with water-injected pulp (12).

This cooler (4) forms a cooling cycle with a compressor (7) and a condenser (8).

The water injection port (12a) provided on the lower surface of the water injection pulp (work 2)
) and the front of the exterior (1).
14) is provided, and the compressor (
In order to control the motor etc. of 7), a control device (11) using a microcomputer or the like is provided.

In this way, the water in the tank (2) is cooled by the cooler (4), and the water-filled pulp (1) is operated by the operation lever (13).
2) is opened, and the cold water in the tank (2) is discharged from the water injection port (12a) of the water injection pulp (12) through the water injection pipe (5), and is used for drinking or the like.

In such a water cooler, a cooler (4) is installed to detect the water temperature in the tank (2) and obtain cold water at an appropriate temperature.
Conventionally, in order to control the operation of
As shown in the publication, a heat-sensitive pipe (17) with a built-in capillary tube is installed at or near the bottom of the tank (2).
) is provided with a temperature sensor, and this heat-sensitive pipe (17)
When the compressor (7) detects a certain temperature, it is assumed that the desired amount of cold water is available and the operation of the compressor (7) is stopped.

[Problem to be solved by the invention]

For example, when trying to obtain extremely low-temperature cold water with a water temperature of 5° C. or lower, the water temperature at the bottom of the tank reaches an equilibrium state at about 4° C., as shown in FIG. 3 (c).

This is because the cold water is not convected throughout the tank (2) and the lower half (
2a) and further accumulates from the bottom part of this lower half (2a).

Therefore, in the conventional method of detecting the water temperature using the heat-sensitive pipe (17) installed at the bottom of the tank (2), there are accuracy errors in the heat-sensitive pipe (17) itself, and the need to store water after reaching an equilibrium state to store cold. Considering that the operation continues for a certain period of time, it is almost impossible to detect the water temperature level.

Therefore, in the conventional method, instead of detecting only the water temperature, the heat-sensitive pipe (17) is brought into contact with the cooler (4).
Extremely low temperatures were detected based on the temperature change in 4).

In this case, it cannot be said that the water temperature can be controlled accurately.

The purpose of the present invention is to eliminate the disadvantages of the conventional example, and to provide temperature control that can accurately detect water temperatures even in the extremely low temperature range, and that allows a large amount of cold water to be obtained since the measurement points are not concentrated in one point but over a wide range. An object of the present invention is to provide a method for controlling the operation of a water cooler, which can also handle abnormal operation when there is a very small amount of water.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a cooling cycle cooler using a compressor or the like on the outer periphery of the lower half of a tank inside the exterior, and a water injection pulp that is connected to a water injection pipe from the tank by operating a lever outside the exterior. A lower temperature sensor is provided at or near the outer wall of the bottom of the tank, and an upper temperature sensor is provided at least above the cooler on the outer wall of the tank, and the outputs of the lower temperature sensor and the upper temperature sensor are controlled. The gist is to install it into a device and measure the water temperature at the top and bottom of the tank at regular intervals, and when the temperature difference falls within a set range, the compressor is controlled on and off using the output of the control device. It is.

[Effect]

In a water cooler, the compressor operates to cool the water in the tank, starting from the bottom.

As shown in FIG. 3, even when the water temperature at the bottom of the tank reaches the equilibrium state of 4° C., the water temperature above the cooler in the lower half of the tank is still at a high temperature.

According to the present invention, the temperature at the bottom of the tank is detected by the lower temperature sensor, and the temperature above the cooler in the lower half of the tank is detected by the upper temperature sensor, and the difference between the temperatures detected by both temperature sensors is within a predetermined range. If it is, the control device turns off the power to the compressor, assuming that there is an averaged amount of cold water in the tank, and then the temperature difference falls within a predetermined range as the temperature rises due to replenishment after taking out the water or due to natural standing. When it runs out, power is turned on to the compressor and cooling operation begins.

Also, when the amount of water in the tank is extremely small or empty, the temperature difference between the temperature of the upper outer wall of the lower half of the tank and the outer wall of the bottom of the tank is reversed due to heat conduction compared to when there is water. If a temperature difference is detected and the operation is stopped as abnormal operation, overloads such as refrigerant liquid returning to the compressor can be prevented early.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal sectional side view of a water cooler in which the operation control method of the present invention is implemented, and the same components as in the conventional example shown in FIG. 5 are given the same reference numerals.

The overall configuration of the water cooler is the same as the conventional example shown in FIGS. 4 and 5, so a detailed explanation will be omitted here.
Also in the present invention, a tank (2) is housed in the upper half of the exterior (1), and the lower half (2a) of the tank (2) is formed into a narrow diameter part, and the outer periphery of this narrow diameter part is A cooler (4) was wound around and attached, and a control device (11) using a microcomputer or the like was disposed on the projecting portion of the upper half of the exterior (1) toward the front side.

In the water heater having such a configuration, in the present invention, in place of the conventional heat-sensitive pipe (17), a lower temperature sensor (18a,) for detecting the temperature at the bottom of the tank (2) is installed on or near the bottom outer wall of the tank (2). A tank (2) is installed on the outer wall above the cooler (4) in the lower half (2a) of the tank (2).
) An upper temperature sensor (18b) was provided to detect the temperature of the upper part.

This upper temperature sensor (18b) may be provided higher than shown in the figure, that is, in the upper half of the tank (2).

FIG. 2 shows a block diagram of temperature control in the present invention,
A power supply circuit (20) and an input device (21) such as a switch for changing set values such as temperature are connected to the input side of the control device (11), and a lower temperature sensor (11) is connected to the control device (11).
8a), the sensor circuit (18c) of the upper temperature sensor (18b) is connected via the A/D converter (19), and a display device F (2) such as a lamp is connected to the output side of the control device (11).
2) and connect the compressor (7) via the drive circuit (23).

The control device (11) includes a lower temperature sensor (18).
The water temperature (T I) at the bottom of the tank (2) detected in a), the lower temperature sensor (18a) and the upper temperature sensor (1)
8b) and the temperature difference ΔtI+ Δt2 detected respectively.
is set in advance so that an off signal is output to the drive circuit (23) of the compressor (7) when the temperature difference becomes less than Δ1°, and an on signal is output when the temperature difference becomes more than Δt8.

Next, how to use it will be explained.

During cold water operation, the drive circuit (23) is connected from the control device (11).
), the compressor (7) is turned on, and the cooler (4) is operated in a cooling cycle to cool the water in the tank (2).

In Figure 3, (a) is the water temperature near the top of the lower half of the tank (2a), (b) is the temperature of the outer wall near the top of the lower half (2a) when the water flow is extremely low, (c) is the water temperature at the bottom of the tank, (D) is the temperature of the outer wall of the bottom of the tank when the amount of water is extremely small, but the lower temperature sensor (18a) detects the water temperature at the bottom of the tank (C), and the upper temperature sensor (18b) detects the water temperature of the bottom of the tank (A). The sensor circuit (18c) detects the water temperature near the area and outputs it from the sensor circuit (18c) to the A/D converter (19), where it is converted into a digital signal and output to the control device (11).

The control device (11) obtains the measurement results of the lower and upper water temperatures of the tank (2) inputted from the A/D converter (19) at regular intervals, and After the temperature at the bottom reaches the set temperature (T,), compare the temperature at the bottom of the tank with the temperature near the top of the lower half of the tank in (a), and make sure that this temperature difference Δtl is below a pre-programmed certain value. When the water in the tank (2) has cooled sufficiently, it is transferred to the compressor (7) via the drive circuit (23).
Turn off the power to the

Then, the water temperature rises as the condensate is used or heat is received from the surroundings, and the specified temperature difference Δt! If it exceeds the limit, the compressor (7) starts to be energized again.

Thereafter, such turning on and off of the compressor (7) is repeated.

When the refrigeration cycle such as the compressor (7) and fan (9) is operated in this way, the water in the narrow diameter part, which is the lower half (2a) of the tank (2), is cooled by the cooler (4). .

The temperature of the water in the tank (2) changes differently depending on its upper and lower positions. For example, as shown in Figure 3, even if the water temperature (c) at the bottom of the tank reaches the equilibrium state of 4°C, the water in the lower half of the tank Part (2a
) The water temperature above the upper part (a) is still in a high temperature state.

Therefore, according to the present invention, the temperature at the bottom of the tank and the lower half (2
a) Since the sensor detects changes in temperature above the upper part, the set value (T1) of the tank bottom water temperature must be adjusted to 4 in the equilibrium state, taking into account variations in the temperature sensor itself, installation procedures, etc.
' Can be set to a temperature with plenty of room above C, and the tank (2
) is at the desired water temperature, so water at a stable temperature can be supplied with high precision.

Furthermore, when a very small amount of water is cooled in tank (2),
As shown in Figure 3, the lower half of the tank (2a
) The temperature of the upper outer wall (b) and the temperature of the bottom outer wall of the tank when the amount of water is extremely small (d) are opposite to those when there is water due to the relationship of heat conduction.

In other words, the temperature difference between the two is Δ1. When detects a negative value,
If the operation is stopped as abnormal operation via the control device (11), the refrigerant liquid returns to the compressor (7), etc.
) can be prevented from being overloaded at an early stage, and it is also possible to improve usability, such as reporting water supply to the user.

〔Effect of the invention〕

As described above, the water cooler operation control method of the present invention measures the temperature at the top and bottom of the tank and controls the operation based on the mutual relationship between them, so the water in the tank remains sufficiently cool and stable. In addition to being able to supply water, it can also accurately detect water temperatures in the extremely low temperature range, and it can also handle abnormal operations when there is a very small amount of water.

[Brief explanation of the drawing]

FIG. 1 is a vertical side view showing a water cooler in which the operation control method of the present invention is implemented, FIG. 2 is a block diagram of the same control, FIG. 3 is a temperature-time correlation diagram showing the operation control operation, and FIG. The figure is an overall perspective view of a water cooler, and FIG. 5 is a longitudinal sectional side view showing a conventional example. (1)... Exterior (2)... Tank (2a
)---Lower half (3)...Lid (4)...Cooler (5)
...Water injection pipe (6) ...Tank holding plate (7)
... Compressor (8) ... Condenser (9) ...
Fan (lO)...Front panel (11)...
・Control device (12)...Water injection pulp (12a)
-...Water inlet (13)...Operation lever (14)
)...Drainage case (15)...Tank fixing plate (16)...Insulating material (17)...Thermal pipe (18a)...Lower temperature sensor (18b),...Upper temperature sensor ( 18c)...Sensor circuit (19)...A/D converter (20)...Power supply circuit (21)...Input device (22) -...Display device (23)...Drive circuit Figure 2 Agent Patent Attorney Masuo Ohatsu Figure 3 Figure 4

Claims (1)

[Claims] In a water cooler, a cooler with a cooling cycle using a compressor or the like is disposed on the outer periphery of the lower half of the tank inside the exterior, and a water injection valve operated by a lever outside the exterior is connected to the water injection pipe from the tank. A lower temperature sensor is provided on or near the outer wall of the tank, and an upper temperature sensor is provided on the outer wall of the tank at least above the cooler, and the outputs of the lower temperature sensor and the upper temperature sensor are input to a control device to control the temperature of the tank at regular intervals. A method for controlling the operation of a water cooler, characterized by measuring the water temperature at the upper and lower parts of the water cooler, and controlling the compressor on and off using the output of a control device when the temperature difference falls within a set range.