JPH046849B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the temperature of hot water in a hot water tank used in hot beverage vending machines and the like.

In such a hot water tank, if one heater is installed at the bottom of the tank, the time it takes for the water temperature to rise to a temperature suitable for sale after the heater is turned on is as follows, assuming that the amount of heat generated by the heater is constant: The smaller the capacity, the faster. However, in order to be able to sell a large amount at once, the capacity of the tank must be increased, so after turning on the heater,
It takes longer to become available for sale.

To solve this problem, heaters are installed above and below the hot water tank. Initially, the upper heater raises the temperature of the water in the upper part of the hot water tank, and when the water temperature in this area reaches the upper limit, the upper heater is turned off. There is a method of heating the water at the bottom by turning off the heater and then turning on the lower heater. However, in the case of such conventional methods,
It is uneconomical because two large-capacity heaters are required, and turning on the upper and lower heaters at the same time consumes a large amount of power, which causes problems with wiring. Excessive power consumption must be prevented by turning off the other heater. Therefore, the control circuit also becomes complicated.

In addition, in the system disclosed in Japanese Utility Model Application Publication No. 51-9348, the inside of the hot water storage tank is partitioned with a partition plate, and the upper part is a hot water storage chamber and the lower part is a heat conversion chamber. A heat exchanger is installed, and the partition plate is equipped with an inflow pipe that allows hot water from the heat exchange chamber to flow into the hot water storage chamber, and an outflow pipe that allows cold water from the hot water storage chamber to flow out to the heat exchange chamber. In this known device, the lower part is used as a heat exchange chamber for obtaining high-temperature hot water, and heat convection is restricted, so the temperature rise in the upper hot water storage chamber is significantly slow, and a portion of the high-temperature hot water in the lower heat exchange chamber is water constantly escapes to the upper hot water storage chamber, so in order to use the hot water in the heat exchange chamber as an instantaneous water heater, the temperature of the heat exchanger must be maintained at a fairly high temperature at all times, resulting in large thermal energy consumption. There's a problem.

The purpose of this invention is to provide one heater only at the top of a large-capacity tank, and use this heater to quickly raise the temperature of the water at the top of the tank to a temperature at which it can be sold, while also increasing the temperature of the water at the bottom as quickly as possible. The goal is to raise the temperature to a point where it can be sold.

That is, in this invention, an upper temperature sensor and a lower temperature sensor are provided in an upper tank and a lower tank, respectively, which are communicated by a communication pipe, a tank is provided in the upper tank, and a circulation propeller driven by a motor is provided in the communication pipe. By controlling the drive motor of the circulation propeller with the upper temperature sensor, the water temperature in the upper tank is maintained within a certain range without turning the heater in the upper tank on and off, and the water temperature in the lower tank is maintained. The purpose of the present invention is to provide a method for controlling the temperature of hot water that quickly raises the temperature of hot water.

The details of the method of this invention will be explained below based on the embodiments shown in the accompanying drawings.

In Fig. 1, 1 is an upper tank and 2 is a lower tank. In the illustrated example, a large tank is partitioned by a partition plate 3 to be divided into an upper tank 1 and a lower tank 2, but the partition plate 3 is omitted. It's okay.

4 is a communication pipe that communicates the upper and lower tanks 1 and 2, and the upper and lower sides thereof are open. This communication pipe 4
A circulation propeller 5 is provided inside, and this propeller 5
When driven by the motor 6, the water in the communication pipe 4 flows downward or upward, thereby circulating the water in the upper tank 1 and the water in the lower tank 2. Therefore, when the upper tank 1 and the lower tank 2 are separate bodies, another communication pipe is provided in addition to the communication pipe 4 so that when the propeller 5 rotates,
The structure is such that the water in the upper and lower tanks 1 and 2 circulates. However, this is just an example, and any other circulation means such as a circulation pump may be used.

7 is a heater installed in the upper tank 1, for example
It is 1KW electric heat. Reference numerals 8 and 9 denote an upper temperature sensor and a lower temperature sensor provided in the upper tank 1 and the lower tank 2, respectively.

In the block diagram of FIG. 2, parts with the same reference numerals as in FIG. 1 indicate the same parts. In this diagram,
10 and 11 are A/D converters that convert analog signals from each temperature sensor 8 and 9 into digital signals;
2 and 13 are temperature data setting devices, for example, setting device 1.
In 2, temperatures of 92°C or higher, 72°C or higher, and 89°C or higher are set, and when the signal from the A/D converter 12 reaches these values, an output signal will be emitted from each output terminal. ing. Also. In the illustrated example, the setting device 13 has an output terminal of 84° C. or higher.

Further, the output terminal of the setting device 12 for temperatures above 72°C is connected to the control circuit 14 of the vending machine, so that while the signal of 72°C or above is input to the setting device 12, a signal indicating that sales are possible is sent to the control circuit 14. There is.

15 and 16 are flip-flop circuits, circuit 1
The output terminal of the circuit 15 is connected to the power control circuit of the heater 7, the output terminal of the OR circuit 17 is connected to the input terminal of the circuit 15, and the AND circuit 1 is connected to the other input terminal.
8 output terminals are connected. Further, one input terminal of the OR circuit 17 is connected to a power-on signal circuit 19.
is connected to the temperature data setter 12, and the output terminal of the temperature data setter 12 of 89° C. or higher is connected to the other input terminal.

Further, the output terminal of the setting device 12 at a temperature of 92° C. or higher is connected to one input terminal of the AND circuit 18;
The output terminal of the setting device 13 having a temperature of 84° C. or higher is connected to the other input terminal.

The control circuit for the motor 6 is connected to the output terminal of the other flip-flop circuit 16.
The output terminal of the setting device 12 having a temperature of 92° C. or higher is connected to one input terminal of the setting device 6. In addition, the output terminal of the OR circuit 20 is connected to the other input circuit, the output terminal of the setting device 12 at a temperature of 89° C. or higher is connected to one input terminal of the OR circuit 20, and the other input terminal of the same circuit is connected to the output terminal of the OR circuit 20. The output terminal of the setting device 13 with a temperature of 84°C or higher is connected to the terminal.

Reference numeral 21 in FIG. 3 is a reference clock pulse oscillator whose output pulses are sent to each setter 12, 13.

The apparatus for carrying out the method of the present invention has the above-mentioned structure, and its operation will now be described.

When the water temperature in the upper and lower tanks 1 and 2 is below 72°C, when the power is turned on, a signal is input to one input terminal 17 of the OR circuit, a set signal is input from the circuit 17 to the flip-flop circuit, and the heater 7 is turned on. Also, at this time, each temperature data setter 12, 1
There is no output signal from 3. Therefore motor 6
has stopped.

When the temperature of the water in the upper tank 1 rises due to the heat generated by the heater 7 and reaches 72° C., a signal indicating that the product is ready for sale is sent to the control circuit 14. The temperature further rises to 92℃
When the temperature reaches , a set signal is sent to the flip-flop circuit 16, and the motor 6 is turned on while the heater 7 remains on.
When turned on, the water in the upper and lower tanks 1 circulates, so the water temperature in the upper tank 1 decreases and the water temperature in the lower tank 2 rises slightly.

When the water temperature in the upper tank 1 drops to 98℃, the setting device 1
The signal from 2 is input to the OR circuit 20, a reset signal is input to the flip-flop circuit 16, and the motor 6 is stopped. Therefore, the temperature of the water in the upper tank 1 starts to rise again.

As the above operation is repeated several times, the temperature of the water in the lower tank 2 gradually rises, and when the temperature reaches 84°C, a signal is input to the OR circuit 20 and the motor 6 is stopped.

In addition, a signal is input from the 84°C output terminal of the setting device 13 to the AND circuit 18, and then the 92°C output terminal of the setting device 12
When a signal is input from the output circuit to the AND circuit 18, a reset signal is input from the AND circuit 18 to the flip-flop circuit 15, and the heater 7 is turned off.

When the heater 7 is turned off and the water temperature in the upper tank 1 drops below 92°C and then below 89°C,
The reset signal is canceled and the heater 7 is turned on.

Figure 3 is a graph showing the changes in the hot water temperature in the upper tank 1 and the lower tank 2 due to the above-mentioned operation, and shows the ON/OFF status of the motor 6 and heater 7. The vertical axis is the temperature (°C) and the horizontal axis is the horizontal axis. The axis shows the passage of time (min) from right to left.

In this figure, line A shows the increase in the hot water temperature in the upper tank 1, and line B shows the rise in the hot water temperature in the lower tank 2.

Also, the line H indicates ON/OFF of the heater 7, and the line M indicates ON/OFF of the motor 6, with the top being ON and the top being ON, respectively.
The bottom is OFF.

As is clear from this figure, the water temperature in the upper tank 1 sends a signal to the control circuit 14 of the vending machine that it is ready to sell.
The time it takes for the temperature to rise to 72°C is extremely short. Moreover, after the temperature of the water in the lower tank 2 rises above the salesable temperature, the ON time of the heater 7 and motor 6 is shortened, resulting in an effect such as saving power consumption.

In addition, if the motor 6 does not rotate for some reason, the hot water in the upper tank 1 may exceed 92°C and boil before the water temperature in the lower tank 2 reaches 84°C, but this can be prevented. Therefore, when the upper temperature sensor 8 detects 96°C, the flip-flop circuits 15 and 16 are reset to
It is recommended to provide a device to turn off the Further, by controlling the control point of the hot water temperature in the lower tank 2 and the rotation time and number of rotations of the motor 6, it is possible to perform temperature control corresponding to the outside temperature.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view showing an example of a hot water tank for carrying out the method of this invention, Fig. 2 is a block diagram of an apparatus for carrying out the method of this invention, and Fig. 3 shows changes in water temperature in the hot water tank. Motor and heater ON/
It is a graph showing OFF. 1... Upper tank, 2... Lower tank, 4... Communication pipe, 5... Propeller, 6... Motor, 7... Heater, 8
...Upper temperature sensor, 9...Lower temperature sensor.

Claims (1)

[Claims] 1 The upper tank and the lower tank are communicated with each other through a communication pipe with the top and bottom open, a means for circulating water in the upper and lower tanks is provided in the communication pipe, a heater is provided in the upper tank, and a means for circulating water in the upper and lower tanks is provided in the communication pipe. An upper temperature sensor and a lower temperature sensor are respectively provided, and when the upper temperature sensor detects that the water temperature in the upper tank has reached the upper limit temperature setting, the circulation means is activated and the cold water from the lower tank is mixed into the upper tank. When it is detected that the water temperature in the upper tank has fallen to the lower limit set temperature, the circulating means is stopped to maintain the water temperature in the upper tank within a certain range and gradually increase the water temperature in the lower tank. When the lower temperature sensor detects that the water temperature in the lower tank has reached the upper limit temperature setting, the heater and circulation means are turned on.
A hot water temperature control method characterized by turning it off.