JPH07310954A - Chilled and warm water generator - Google Patents

Abstract

PURPOSE:To prevent a tank from being abnormally heated when the warm water generation is conducted when no water is contained in the tank. CONSTITUTION:A heater 7 is controlled ON, OFF by temperature sensing means 18 provided in a tank. The energization of the heater 7 is stopped by a controller 19 if the temperature of the means 18 after a predetermined time from when the temperature of the means 18 reaches an unnecessary heating temperature (the OFF temperature of the heater 7) so that the heater 7 is turned OFF, becomes the temperature of detecting no-water heating further higher by a predetermined temperature than the unnecessary heating temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a table-top type cold / hot water machine capable of switching between cold water operation and hot water operation.

[0002]

2. Description of the Related Art The structure of a chiller / heater will be described with reference to FIGS.

In the figure, reference numeral 1 denotes an exterior, which accommodates a tank 2 inside and places a lid 3 in the upper opening of the tank 2. The lower portion of the tank 2 has a small diameter, and is held by a horizontal tank holding plate 4 that spans the inside of the exterior 1 and a tank fixing plate 5 that surrounds the lower portion of the tank 2.

A cooler 6 is attached around the lower portion of the tank 2, and a heater 7 having a heating element built into an aluminum die cast is attached to the bottom portion of the tank 2. To detect the temperature of water in
First thermostat 16 and second thermostat 17
Is attached in contact with the tank 2. A third thermostat 23 is attached to the heater 7 so that the heater 7
Detects the temperature of.

A heat insulating material 8 is arranged between the lower portion of the tank 2 and the fixed plate 5 so that the water in the tank 2 can be insulated from the outside.

A compressor 9 and a fan motor 10 are arranged as a machine chamber in the lower part of the exterior 1 partitioned by the tank holding plate 4, and a condenser 11 is provided on the back side of the exterior 1 to connect them and a cooler 6. Constitutes a refrigeration cycle.

Further, from the bottom of the tank 2, a water injection pipe 12
And a water injection valve 14 for taking out water in the tank by operating the lever 13 is attached to the tip thereof. 1
Reference numeral 5 denotes a changeover switch for switching between cold water operation and hot water operation.

With such a structure, during cold water operation,
The first thermostat 16 detects the temperature in the tank 2, and if the temperature is equal to or higher than the required cooling temperature, the compressor 9 and the fan motor 10 are operated to cool the water in the tank 2 with the cooler 6. If the temperature is below the unnecessary cooling temperature, the compressor 9,
The operation of the fan motor 10 is stopped and the temperature of the water in the tank is adjusted.

On the other hand, during hot water operation, the temperature inside the tank 2 is detected by the second thermostat 17, and if the temperature is below the required heating temperature, the heater 7 is operated, and if the temperature is above the unnecessary heating temperature. If there is, stop the operation of the heater 7,
Adjust the temperature of the water in the tank.

When the water injection valve 14 is opened with the lever 13, cold water or hot water in the tank 2 is discharged from the water injection valve 14 through the water injection pipe 12.

When hot water operation is carried out without water in the tank 2, the temperature difference between the heater 7 mounting surface of the tank 2 and the second thermostat 17 becomes large, and the bottom surface of the heater 7 and the tank 2 becomes 100. Due to the abnormally high temperature of ℃ or more, the third thermostat 23 operates (for example, 150 ℃) to stop the energization of the heater 7.

[0012]

However, with such a configuration, the heater of the tank 2 detects the empty heating by the third thermostat 23, such as when the water in the tank 2 is exhausted during operation. 7 Since the mounting surface becomes hot, it is dangerous to touch it with care, and the tank 2 may be deformed or discolored.

The present invention solves the above-mentioned problems, and when hot water operation is performed without water, it is possible to detect it and to stop energizing the heater and the tank before the temperature becomes high. It is intended.

[0014]

In order to solve the above-mentioned problems, the chiller-heater of the present invention accommodates a tank having a heater and a cooler in its exterior, and a water injection pipe from this tank is provided with a water injection valve operated by a lever. In combination, the temperature detection means is provided in the tank, and in the case of hot water operation by the heater, the heater is ON-OFF controlled by the temperature detection means, and the temperature of the temperature detection means is an unnecessary heating temperature (OFF temperature of the heater). And when the temperature of the temperature detecting means after a certain time after the heater is turned off is equal to or higher than the empty heating detection temperature which is a certain temperature higher than the unnecessary heating temperature, the energization of the heater is stopped thereafter. It is the one.

[0015]

According to the present invention, when the hot water operation is performed without water in the tank, the temperature of the temperature detecting means is maintained even after the temperature of the temperature detecting means exceeds the heater OFF temperature and the energization of the heater is stopped. Since the temperature of the heater mounting portion is higher than the temperature of the temperature detecting means, the temperature continues to rise due to heat conduction from the heater and becomes equal to or higher than the empty heating detection temperature after a certain time has passed since the heater was turned off, after which the power supply to the heater is stopped.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The same parts as those of the conventional chiller-heater are designated by the same reference numerals, detailed description thereof will be omitted, and only different parts will be described.

In FIG. 1 and FIG. 3, reference numeral 18 is a temperature detecting means, such as a thermistor mounted in contact with the tank 2, for detecting the temperature of the water in the tank 2. Reference numeral 20 denotes a changeover switch for switching between cold water operation and hot water operation, which is located at the front of the exterior 1.

Reference numeral 19 is a control device, which has a heater 7 inside.
Empty-fired timer 2 that counts the time since stopping
4 and receives the temperatures of the changeover switch 20 and the temperature detection means 18 as input, and outputs the operation command of the compressor 9, the heater 7 and the fan motor 10 to the drive means 21 and the drive means 22. The drive means 21 is connected to the heater 7, and the drive means 22 is connected to the compressor 9 and the fan motor 1.
It is connected to 0.

The operation of the above arrangement will be described with reference to FIG. The operation of the controller 19 will be described below.
First, in step 1, it is determined whether the setting of the changeover switch 20 is cold water operation or hot water operation.

If it is determined in step 1 that the cold water is set, the process proceeds to step 2, and it is determined whether the temperature of the temperature detecting means 18 is higher than or equal to the required cooling temperature in the cold water operation. For example, the process proceeds to step 3, and the operation command of the compressor 9 and the fan motor 10 is output to output the compressor 9
Also, the fan motor 10 is operated. If it is determined in step 2 that the temperature is not higher than the required cooling temperature, the process proceeds to step 4, and a stop command is output to the compressor 9 and the fan motor 10 to stop the compressor 9 and the fan motor 10.

After the operations of step 3 and step 4, the process returns to step 2 again, and by repeating this operation, the water in the tank 2 is cooled to a constant temperature.

If it is determined in step 1 that the hot water operation is set, the process proceeds to step 5 and the temperature detecting means 1
The temperature of 8 is the heating temperature required for cold water operation (eg 70 ° C)
If it is below the required heating temperature, the process proceeds to step 6 to output an operation command for the heater 7 to operate the heater 7.

If it is determined in step 5 that the temperature is not lower than the required heating temperature, the process proceeds to step 7 and it is determined whether the temperature of the temperature detecting means 18 is equal to or higher than the unnecessary heating temperature (for example, 80 ° C.).

If it is not judged that the temperature is not higher than the unnecessary heating temperature, the process proceeds to step 8 to judge whether the heater 7 is currently operated, and if it is operated, step 6
Go to.

If it is determined in step 7 that the temperature of the temperature detecting means 18 is equal to or higher than the unnecessary heating temperature, or if it is determined in step 8 that the heater 7 is not in operation, the process proceeds to step 9 to give a command to stop the heater 7. Output, heater 7
To stop.

After that, the routine proceeds to step 10, where the counting of the empty heating timer 24 is started. Then step 11
Then, the time-up of the count of the empty heating timer 24 is checked to determine whether a predetermined time T (for example, 1 minute) has elapsed.

If the predetermined time has elapsed, step 1
2 and the temperature of the temperature detecting means 18 is higher than the unnecessary heating temperature by a certain temperature, and the temperature of the empty heating detection is 90 ° C., for example.
It is determined whether or not the above.

As shown in FIG. 4, when the water in the tank 2 is sufficient, the temperature of the temperature detecting means 18 reaches the unnecessary heating temperature, and when the heater 7 is stopped, the heat of the heater 7 is released from the tank 2.
The temperature of the temperature detecting means 18 begins to drop immediately because it is absorbed by the water inside, but when there is almost no water in the tank 2, the temperature difference between the heater 7 and the temperature detecting means 18 increases during heating, Since the heat of the heater 7 does not escape to the water in the tank 2 after the heater 7 is stopped, the heat of the heater 7 travels through the tank 2 and heats the temperature detecting means 18. Therefore, even after the heater 7 is stopped, the temperature is further increased. Continues to rise. This rate of temperature increase increases as the amount of water in the tank 2 decreases.

Therefore, when there is almost no water in the tank 2, the temperature of the temperature detecting means 18 rises even after the heater 7 is stopped, and after the predetermined time T (1 minute) elapses after the heater 7 is stopped, it is emptied. The temperature becomes equal to or higher than the burning detection temperature, and it is determined in step 12 that the temperature of the temperature detecting means 18 is equal to or higher than the empty heating temperature. In step 13, the heater 7 is stopped and remains as it is.

When there is sufficient water in the tank 2, the temperature of the temperature detecting means 18 does not exceed the empty heating detection temperature in step 12, so that the process proceeds to step 5 again and the above operation is repeated so that the temperature in the tank 2 is reduced. Heat the water to a constant temperature.

Therefore, even if the water in the tank 2 becomes almost empty, the tank 2 will not be abnormally heated.

[0032]

As is apparent from the above description, in the hot and cold water machine of the present invention, in the case of hot water operation by the heater, the temperature detecting means provided in the tank controls the heater ON / OFF, and the temperature detecting means is also provided. If the temperature of the temperature detecting means after a certain time after the temperature reaches the unnecessary heating temperature and the heater is turned off is equal to or higher than the empty heating detection temperature which is higher by a constant temperature higher than the unnecessary heating temperature, then the heater is heated. Since the power supply to the tank is stopped, the tank and the heater do not become abnormally heated and do not reach a high temperature due to the empty heating.

[Brief description of drawings]

FIG. 1 is a block diagram of a control circuit of a chiller / heater showing an embodiment of the present invention.

FIG. 2 is a flowchart showing the control of the control device of the chiller-heater.

FIG. 3 is a cross-sectional view of the chiller / heater.

FIG. 4 is a time chart showing a temperature change of a temperature detecting means of the same water heater.

FIG. 5 is a cross-sectional view of a conventional water heater / cooler.

FIG. 6 is an electric circuit diagram of the water heater / cooler.

[Explanation of symbols]

 1 Exterior 2 Tank 6 Cooler 7 Heater 12 Water Injection Pipe 13 Lever 14 Water Injection Valve 18 Temperature Detector 19 Control Device

Claims (1)

[Claims] 1. A heater comprising a tank having a heater and a cooler housed in an exterior, a lever-operated water injection valve connected to the tank via a water injection pipe, and a temperature detection means provided in the tank. In the case of hot water operation by the above, the heater is controlled to be turned on and off by the temperature detecting means, and the heater is turned off when the temperature of the temperature detecting means reaches an unnecessary heating temperature at which the heater is turned off. If the temperature of the temperature detecting means is equal to or higher than the unnecessary heating temperature, which is a constant temperature higher than the unnecessary heating temperature, then a hot and cold water machine having a control device for stopping energization of the heater thereafter.