JP3352764B2 - Control unit for water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chiller / heater for storing chilled / hot water for beverages, and more particularly to a control device for a chiller / heater capable of displaying an abnormality when an abnormality occurs.

[0002]

2. Description of the Related Art Referring to FIG.

[0003] An upper tank 2 is provided on the upper part of the case 1, an upper lid 3 which can be opened and closed is provided on the upper part of the upper tank 2, and a lower tank 5 is provided integrally with the upper tank 2.
The lower tank 5 is provided with a heat insulating material 4 provided in the case 1.
It is covered with and supported. A water supply port 7 is connected to the lower tank 5, and a tray 8 is provided in the case 1 below the water supply port 7. A cooling pipe 9 is wound around the outer periphery of the lower tank 5, and a heater 10 is provided at the bottom of the lower tank 5. In the case 1 below the lower tank 5, a machine room 11
The compressor 12, the condenser 13, the condenser fan motor 14 and the like are provided in the machine room 11.

FIG. 8 shows a refrigeration cycle 15 of the cooling pipe 9.
And a compressor 12, a condenser 13, a capillary tube (expansion valve) 16, and a cooling pipe 9 are connected in this order.

[0005] In FIG. 7, the case 1 is provided with a control device 17 that controls the refrigeration cycle 15 and the heater 10 to control the temperature of cold water and hot water. The controller 17 drives the compressor 12 and the condenser fan motor 14 during the chilled water operation, cools the water in the lower tank 5 by evaporating the refrigerant passing through the cooling pipe 9, controls the chilled water temperature, and During the hot water operation, the heater 10 is energized to control the temperature of the hot water. Reference numeral 18 denotes a water supply lever.

[0006]

The temperature control of the chilled / hot water of the chilled / hot water machine is performed by detecting the temperature with a sensor and turning on the compressor 12 and the heater 10 so that the temperature of the chilled / hot water reaches the set temperature.・ OFF control. This sensor is
There is one that detects using two for cold water and one for hot water, and one that detects by switching between two sensor circuits for cold water and hot water with one sensor, but one sensor rather than using two sensors. The one that mainly detects and switches the sensor circuit according to the temperature detection region is used.

In the temperature control of the chiller / heater, when the temperature of the hot water in the tank is not properly controlled, for example, in the case of the chilled water control, if the chilled water cannot be cooled to the set temperature, the refrigerant gas leaks to the tank. The supply of water is always supplying warm water, and the compressor remains in the ON state. In this state, it is unavoidable to perform heavy control, but if it is too cold for the set temperature, There is a problem in that cold water always enters the tank due to a sensor failure or if the cooling operation is continued in this state, the water in the tank becomes ice.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a control device for a hot / cold water machine capable of appropriately controlling the temperature of hot water in a tank when an abnormality occurs.

[0009]

Means for Solving the Problems To achieve the above object, a first invention is to provide a heater for heating water in a tank for storing cold and hot water for drinking, and a refrigeration cycle for cooling the water in the tank. And a sensor for detecting a water temperature, in the control device of the chiller / hot water machine capable of the cold water operation and the hot water operation, while operating in the cold water operation mode or the hot water operation mode, the temperature of the cold water or hot water in the tank is set to the set temperature. When it is separated by more than a predetermined temperature, it switches to the reverse operation mode and operates for a predetermined time , and then detects the cold water or hot water temperature and
A control circuit for detecting the presence or absence of abnormality by comparing the temperature with a set temperature is provided. The second invention is a heater for heating water in a tank for storing cold and hot water for beverages, of a refrigeration cycle for cooling water, in the control device of the chiller that includes a sensor for detecting the water temperature, the sensor, connect the switching circuit to detect switched to cold water and for hot, cold water sensor The switching circuit is switched so as to detect both the hot water and hot water, and the cooling circuit before and after the switching is switched.
Compare the reading temperatures for water and hot water, and
If the reading temperature for hot water is approximately the same, it is considered normal and the reading
Are those taken temperature having a control unit for determining an abnormality when the difference further third invention, switching circuit, a plurality of resistive elements selected by turning on and off of the switching element for adjusting the output voltage of the sensor The control unit is configured to control the temperature by turning off the switching element when detecting an abnormal failure of the switching element.

[0010]

According to the above construction, in the first aspect, when the sensor detects the temperature of the cold or hot water, it is determined that the temperature is different from the set temperature in the operation mode, and the operation mode is switched to the reverse operation mode for a predetermined time. Run for hours and then cool
By comparing the hot water temperature with the set temperature, various abnormalities can be determined.
Can be turned off. Further, in the second invention, both the cold water and the hot water are switched by a switching circuit, and the reading temperature before and after the switching is switched.
If the temperatures are almost the same, there is no difference between
If so, the switching circuit is determined to be defective and abnormal. In the third aspect, when the sensor circuit is defective, the temperature can be controlled to an appropriate temperature by controlling the temperature with the temperature in a state where the switching circuit is not switched.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

First, the configuration of the water heater is the same as in FIGS.

FIG. 1 is a circuit diagram of a control device for a water heater / heater according to the present invention.

In FIG. 1, the compressor 12 and the condenser fan motor 14 of the refrigeration cycle 15 are connected to a chilled water relay 20.
, And the heater 10 is connected to the commercial power supply 21 via a hot water relay 22.

A control unit 23 is connected to a sensor 24 for detecting a water temperature, and is connected to an operation unit 25 having a changeover switch for switching between a cold water operation mode and a hot water operation mode and an operation key for setting a set temperature of the cold and hot water. In addition, a display device 26 for displaying an operation mode, a water temperature, and an abnormal state described later is connected. The control device 23 controls drivers 27 and 28 that open and close the relays 20 and 22, a control circuit 29 that receives the detection value of the sensor 24 and drives the drivers 27 and 28, and controls the operation of the operation unit 25. An interface 30 for inputting to the circuit 29;
And a display control circuit 31 for displaying the information on the display device 26.

In the above, the control device 23 uses the detected value from the sensor 24 during the normal cold / hot water operation.
0, 22 are opened and closed, and the compressor 12, the condenser fan motor 14 or the heater
Is turned ON / OFF.

In the cold / hot water operation, if the supply water temperature is abnormal, or if the sensor 24 is defective and the water temperature is separated from the set temperature by a predetermined temperature (for example, 5 ° C.), the operation mode is switched to the reverse operation mode. And an error message is displayed.

This will be described with reference to FIGS.

FIG. 2 shows an example of the cold water operation mode.

The water temperature is ± 2 ° C. with respect to the set temperature (5 ° C.)
, The compressor is turned on and off,
The operation is performed with the heater 10 turned off.
If the temperature is lower than 0 ° C for 1 minute, the compressor is turned off, the heater is turned on and the heater is turned on for 15 minutes in the reverse operation mode to raise the water temperature once to the set temperature. To raise. In this case, the display of the display device performs an abnormal display of E1 indicating that the display is abnormal from the normal display. After performing the operation for 15 minutes in the reverse operation mode (hot water operation mode), the compressor and the heater are both turned off for 3 minutes, and then the compressor is turned ON / OFF for 1 hour with the abnormality display E1.
If no abnormalities occur after performing the chilled water operation with the F control, the compressor is turned off and stopped for 5 minutes. After a further 3 minutes delay, the display returns to the normal display and the normal cooling control is performed. In this case, E1 is displayed and all stops are performed.

FIG. 3 shows an example of the hot water operation mode, and the basic control is the same as that of the cold water operation.

First, the temperature of the hot water is set to ± 90 ° C.
When the temperature is kept at 2 ° C., the heater is turned on / off and the compressor is turned off.
If the temperature is higher than a predetermined temperature (for example, 5 ° C.), for example, if 95 ° C. or more is continued for 1 minute, the heater is turned off, the compressor is turned on, and the reverse operation mode (cold water operation mode) is turned on.
Run for 5 minutes and lower the water temperature once below the set temperature. In this case, the display of the display device performs an abnormal display of E1 indicating that the display is abnormal from the normal display. After performing the operation for 15 minutes in the reverse operation mode, the heater and the compressor are turned OFF for 3 minutes, and then the heater is turned ON / OFF for 1 hour with the abnormality display E1.
If no abnormality occurs after controlling and performing the hot water operation, the heater is turned off and stopped for 5 minutes. After a further 3 minutes delay, the display returns to the normal display and the normal hot water control is performed. , Display E1 and perform a complete stop.

[0023] but did not know what kind of abnormality or because there was no display function conventional than above, the user by performing an abnormal display can recognize the abnormality at a glance. In addition, when an abnormality occurs (when the temperature is separated from the set temperature by a predetermined temperature), by setting the reverse operation mode, it is possible to improve overcooling during cold water operation and overheating during warm water operation, and thereafter for about one hour. Since the control state is checked and it is determined whether to return to the normal operation or to stop when it is recognized as abnormal, it is possible to check for a malfunction of the control.

FIG. 4 is a circuit diagram showing another embodiment of the present invention, wherein the temperature of the water is taken as one sensor 24, and when the temperature of the cold or hot water is detected, it is switched by a switching circuit 32. .

First, the sensor 24 is composed of, for example, a thermistor. One of the sensors 24 is connected to a control voltage source 33 in the control device 23, the other is grounded via a resistor 34, and another resistor 35 is connected in parallel with the resistor 34. And the transistor 36 are connected to form the switching circuit 32. The voltage applied between the sensor 24 and the resistors 34 and 35 is used as the temperature information as the control unit 3.
7, the control unit keeps the transistor 36 in the OFF state when detecting cold water, for example, and turns on the transistor 36 when detecting hot water so that the current flows also to the resistor 35. To detect the temperature.

In FIG. 4, reference numeral 21a denotes an outlet connected to a commercial power supply, 37 denotes a power switch, and 38 denotes a power supply section of the control device 23.

In the embodiment of FIG. 4, when the normal cold / hot water operation is performed, the switching is performed by turning off or on the transistor 36 of the switching circuit 32. When the switching cannot be substantially performed, that is, the transistor 36 is defective. When an abnormality occurs, the control unit 37 recognizes this, displays it on the display unit 25, and reads and controls the temperature information of the sensor 24 in a state where no switching is performed (a cold water detection state).

FIG. 5 shows the relationship between the temperature T and the sensor output V, wherein a shows the temperature characteristics when hot water is used, and b shows the temperature characteristics when cold water is used.

When the chilled water temperature is detected, the output V
In the case of 2, the temperature is T1, and if the switching circuit 32 is normal, switching to hot water detection causes the sensor output at the temperature T1 to change from V2 to V1, but if the switching is defective, the output V2 remains unchanged. And the reading of the hot water temperature is based on the characteristic a of the hot water.
The temperature becomes higher than the temperature T2 and the actual temperature T1.

Therefore, in this example, the control unit 37 first stores the temperature at the time of OFF, and then turns the switching circuit 32 ON.
, And comparing the two values, it is possible to determine whether it is normal or abnormal. In other words, the water temperature is read at both the detected temperature at the time of cold water and the detected temperature at the time of hot water, and by comparing the two read temperatures, it is determined to be normal if the read temperatures are substantially the same, and to be abnormal if the temperatures are different. it can. This judgment of normality is made 1 to 4 based on the accuracy of the sensor and the like.
It is normal if the temperature is within the range of ° C.

FIG. 6 shows a flow chart of abnormality detection during hot water operation.

First, when the hot water operation is started, the switching circuit turns off the transistor and stores the input (A) at that time, then turns on the switching circuit and inputs the data at that time (B). It is determined whether or not | AB |> α. If α is equal to or less than (yes), the state is determined to be normal. If α is equal to or more than α (no), an abnormality is determined to be determined as abnormal and the switching circuit is in the OFF state, ie, By controlling the temperature of the hot water based on the characteristics of the temperature of the cold water, an emergency operation can be performed, and the device can be used even during the period until repair.

[0033]

According to the present invention, in the first invention, when the detected temperature is far from the set temperature, it is determined that there is an abnormality, and by switching to the reverse operation mode, excessive cooling or excessive heating can be prevented. . Further, in the second invention, the switching circuit is switched for both cold water and hot water to detect the temperature, and the change width of the detected temperature at this time is detected, so that abnormality of the switching circuit can be detected. In the third invention, when the sensor circuit is defective, the emergency operation can be performed by controlling the temperature by turning off the switching element of the switching circuit.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing control of a chilled water operation mode in the present invention.

FIG. 3 is a diagram showing control of a hot water operation mode in the present invention.

FIG. 4 is a diagram showing another embodiment of the present invention.

5 is a diagram showing a relationship between a sensor temperature and an output when the switching circuit of FIG. 4 is switched.

FIG. 6 is a diagram showing a flowchart of the embodiment of FIG. 4;

FIG. 7 is a diagram showing an overall view of a hot and cold water machine.

FIG. 8 is a diagram showing a refrigeration cycle of the water heater.

[Explanation of symbols]

 Reference Signs List 10 heater 12 compressor 14 fan motor for condenser 15 refrigeration cycle 24 sensor 29 control circuit

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F25D 11/00 102 F25D 29/00

Claims (3)

(57) [Claims] 1. A heater for heating water in a tank for storing cold and hot water for drinking, a refrigeration cycle for cooling the water in the tank, and a sensor for detecting a water temperature, wherein cold water operation and hot water operation are performed. In a control device of a possible chiller / hot water machine, when operating in the chilled water operation mode or the hot water operation mode, when the chilled water or hot water temperature in the tank is more than a predetermined temperature from the set temperature, the operation mode is switched to the reverse operation mode. Operate for a predetermined time , then detect the temperature of cold or hot water and
A control device for a water heater and a water heater, comprising a control circuit for comparing the temperature with a set temperature to detect the presence or absence of an abnormality. 2. A control device for a water heater and a water heater having a heater for heating water in a tank for storing cold and hot water for beverage, a refrigeration cycle for cooling the water in the tank, and a sensor for detecting the water temperature. in, sensors, connecting the switching circuit to detect switched to cold water and for hot water, with switching the switching circuit to detect both for the cold water and hot water sensors, and hot water for cold water of the switching back and forth Reading temperature
And the reading temperatures for cold water and hot water are almost the same.
A control device for a water heater and a water heater, comprising: a control unit for determining that the reading temperature is normal if the readings are different and determining that the reading temperature is abnormal when the reading temperatures are different . 3. A switching circuit comprising a circuit for adjusting a sensor output voltage by selecting a plurality of resistive elements by turning on / off a switching element, wherein a control unit turns off the switching element when detecting an abnormal failure of the switching element. 3. The control device for a water / water heater according to claim 2, wherein temperature control is performed as a state.