JPH0894170A - Antifreezing device for bath heater - Google Patents

Abstract

PURPOSE: To provide an antifreezing device with a simple structure, decrease noise and save consumed power by switching the driving voltage of a pump during antifreezing operation so as to be lower than maximum voltage during circulating and heating operation. CONSTITUTION: During antifreezing operation, lowering of atmosphere temperature in the equipment of a bath heater 1 to a prescribed temperature is recognized by a thermometal cut-out 6 and the phase α of a pump 8 is set to 0 deg. by a controller 7 go that an operation is started. When the phase angle is changed from α=0 deg. to α=180 deg. in a phase angle control, the driving voltage of the pump 8 is decreased from rated voltage to 0V. Accordingly, the pump 8 is initially rotated with full power. At this time, it is recognized that water is contained in a bath tub 4 and the water is continuously stably circulated for 10 seconds by a water flow switch 9. Then, when a previously stored phase angle exists, the phase angle is changed to that stored angle to drive the pump 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a freeze prevention device for a forced circulation type bath kettle.

[0002]

2. Description of the Related Art Conventionally, for the freeze prevention of a forced circulation type bath kettle, a decrease in the ambient temperature of the circulation circuit is detected by a freeze prevention thermoswitch, and when the temperature falls below a predetermined temperature, the pump is started to activate the bathtub. Some water or hot water (hereinafter referred to as bath water) is circulated in a heat exchanger of a bath kettle. Further, in the case where the pump is a self-priming pump, since it holds priming water inside, some self-priming pumps run idle to prevent freezing of this priming water even when there is no bath water. Alternatively, as disclosed in Japanese Patent Laid-Open No. 4-332337, the pump itself is provided with an antifreezing heater, and when there is bath water in the bath, the bath water is circulated, but when there is no bath water in the bath, the pump is stopped. In some cases, the antifreezing heater is turned on.

[0003]

However, since the pump is driven in the same manner as in the circulation heating operation, the rotation speed of the driving motor and the flow rate of the circulating water are unnecessarily high, and as a result, a humming noise or the like occurs. There was a problem that the noise was loud. In addition, the type of idling has a large rotation noise. Not only that, but if it is driven for a long time with a large number of rotations, the priming in the pump will decrease. In the case of the type having the antifreezing heater which solves this, it is necessary to newly assemble the antifreezing heater as a part and assemble it, resulting in an increase in cost. The antifreezing device of the present invention has an object to solve the above problems, reduce noise with a simple configuration, and save power consumption.

[0004]

The first antifreeze device for bath tub according to the present invention for solving the above problems heats the circulating water while circulating the bath water in the circulation circuit by the pump. Used in a forced circulation bathtub that returns to the bathtub, when the ambient temperature of the circulation circuit drops below a predetermined value when the bathtub is not operating, the pump is driven to bring the bath water into the circulation circuit. In the antifreezing device that circulates to prevent freezing, the gist of the invention is to switch the drive voltage of the pump during the above antifreezing so as to be lower than the maximum voltage during the above circulating heating operation.

The second antifreeze device for bathtubs according to the present invention is the first antifreeze device for bathtubs, wherein the pump drive voltage at the time of antifreezing is ensured to circulate the bath water. The point is to switch to the lowest voltage.

[0006]

According to the first bath freeze prevention device of the present invention having the above structure, the pump is operated to prevent the freeze when the ambient temperature drops below a predetermined value. At that time, the drive voltage of the pump is changed and the operation is switched so as to be smaller than that during the circulation heating operation. Therefore, the number of rotations of the pump does not increase more than necessary and the flow rate of the circulating water does not increase, so that it is possible to reduce the noise such as a humming noise. Also,
The power consumption of the pump at that time is also small.

In the second antifreeze device for bathtub of the present invention, when the ambient temperature is lowered and the pump is operated to prevent the freezing, the drive voltage of the pump is switched to the lowest voltage for ensuring the circulating water. To drive. That is, since the number of revolutions of the pump and the flow rate of the circulating water are reduced to the minimum to operate, the noise such as a humming noise can be reduced to the minimum. Also, the power consumption of the pump at that time is minimal.

[0008]

Embodiments In order to further clarify the structure and operation of the present invention described above, an embodiment of the antifreezing device for a bathtub according to the present invention will be described below. FIG. 1 is a schematic configuration diagram of an automatic bath kettle with hot water supply as one embodiment. Automatic bath kettle with hot water supply 1
A circulation heating circuit 2 (hereinafter simply referred to as a bath kettle 1) is connected to a bath 4 by an external pipe 10 and circulates and heats bath water.
And a hot water supply circuit 3 for supplying hot water to the bathtub 4 and the general hot water supply circuit 19.
And a controller 7 for controlling the operation of both circuits, and a thermoswitch 6 for detecting the ambient temperature in the instrument is provided below the instrument. The circulation heating circuit 2 includes a combustion chamber 22 to which combustion air is supplied by a fan 24 and a combustion chamber 22.
A burner 23 for burning gas inside, a circulating passage 27 in the kettle for circulating bath water, a heat exchanger 21 for heating the circulating water by gas combustion, and a gas conduit 17 for supplying gas to the burner 23. A gas electromagnetic valve 26 that opens and closes the gas flow path, a gas governor 25 that keeps the gas pressure constant, and an ignition device (not shown). In this shuttle circuit 27,
A pump 8 for forcibly circulating bath water, a water flow switch 9 for detecting the presence or absence of circulation of bath water, and a thermistor 28 for detecting hot water temperature are provided. In addition, the pump 8 is a self-priming pump, and has a configuration in which the priming water used at the time of startup is always held inside.

The hot water supply circuit 3 includes a combustion chamber 32 to which combustion air is supplied by a fan 34, a burner 33 for burning gas in the combustion chamber 32, and heat for heating water supplied from a water inlet by gas combustion. The exchanger 31, a gas conduit 37 that is a gas supply path to the burner 33, a gas solenoid valve 36 that opens and closes the gas flow path, and a proportional control valve 35 that controls the gas amount.
And an ignition device (not shown). The water inlet is provided with a water governor 38 and a hot water supply amount sensor 39 that is located downstream of the water governor and detects the flow of water. The outlet is branched from the heat exchanger 31 downstream to the general hot water supply circuit 19 to the circulation heating circuit unit 2. The pipe 18 is provided with a thermistor 30 for detecting the hot water temperature after heating, a drop water amount sensor 11 for detecting the hot water discharge amount, and a hot water supply solenoid valve 12 for opening and closing the hot water passage.

The controller 7 performs circulation heating control, automatic hot water supply control, and the like, and includes a CPU, RAM, and ROM forming a well-known arithmetic logic operation circuit (not shown), an input interface for inputting signals from various sensors, It is composed of an output interface for outputting drive signals to various actuators. In FIG. 1, the input / output relationship of only the thermoswitch 6 and the pump 8 is shown and the others are omitted. The controller 7 includes a remote control 5 for remote operation.
Are connected.

Hot water supply to the bathtub 4 is started by operating an automatic hot water supply switch (not shown) of the remote controller 5. First, the automatic hot water supply switch is pushed to open the hot water supply solenoid valve 12, and the fan 34 is rotated by the signal from the hot water supply water amount sensor 39. Then, the gas solenoid valve 36 is opened to supply the fuel gas to the burner 33 to start combustion. . Based on the deviation between the detected temperature of the thermistor 30 and the set temperature, the opening temperature of the hot water is maintained constant by adjusting the opening of the proportional control valve 35 and the rotation speed of the fan 34 to feedback control the hot water temperature. Thus
When the amount of water detected by the drop water amount sensor 11 reaches the set amount of water, the hot water supply solenoid valve 12 is closed and the hot water supply is stopped. After that, the pump 8 is rotated to start the circulation of the hot water, and when the circulation of the hot water is confirmed by the water flow switch 9, the fan 24 is driven and the gas solenoid valve 26 is opened to supply the fuel gas to the burner 23. When the hot water temperature is detected by the thermistor 28 and reaches the set temperature, the pump 8 is stopped and the gas solenoid valve 26 is closed to extinguish the fire.

Next, the freezing prevention process of the bath pot 1 will be described with reference to FIG.
This will be described with reference to the flowchart of. First, the thermoswitch 6 is used to check whether the ambient temperature in the equipment of the bathtub 1 has dropped to a predetermined temperature. If the ambient temperature is lower than the predetermined temperature (S1, YES), the controller 7 controls the phase angle of the pump 8 ( After that, the operation is started after setting 0 degree (α = 0 °) (expressed by α) (S2). In the phase angle control, when the phase angle is changed from α = 0 ° to α = 180 °, the drive voltage to the pump 8 decreases from the rated voltage to 0V. In this embodiment, α is 0 °, 50 °, 70 °, 9
The drive voltage of the pump 8 is switched by using 6 kinds of values of 0 °, 95 °, 98 °. Therefore, in step 2, first, rotation is performed at full power. At that time, when there is bath water in the bathtub 4 and the stable circulation of the bath water is confirmed by the water flow switch 9 for 10 seconds (S3, S4, YES), the process proceeds to the next step 5. In step 5, it is confirmed whether or not the phase angle is previously stored, and if there is the stored phase angle (S5, Y
ES), the stored phase angle is changed (α = 0 ° → stored value), and the pump 8 is driven (S6). When the phase angle is not stored (S5, NO), α = 9 for the time being
Store 8 ° (S9), change to the stored value (α = 0
Drive (° → 98 °) (S6). As a result of the test of this embodiment, it is known that the pump 8 cannot be rotated at a setting exceeding the phase angle of 98 ° (for example, 110 ° or 120 °). It will be driven by power. Thus the water flow switch 9
When the circulation of bath water is confirmed by (S7, YE
S), the operation is continued as it is, and the rise of the atmospheric temperature in the equipment is detected by the thermoswitch 6 (S20, YES).
Then, the operation of the pump 8 is stopped (S21), and the process returns to step 1. In other words, when the ambient temperature in the appliance becomes equal to or lower than a predetermined temperature, the pump 8 is once driven at the phase angle α = 0 to check the water flow, and then the pump 8 is antifreeze-operated at the stored phase angle α to the predetermined temperature. It will stop when you return to.

In step 6, if the circulation of the bath water by the water flow switch 9 is not confirmed (S7, NO) even if the operation is performed at the previously stored phase angle (S7, NO),
Then, the drive voltage of the pump 8 is set to the phase angle 0.
Degree (α = 0 °), and operate (rotation speed increases),
In the subsequent processing, the lowest voltage (phase angle) with which the pump 8 can rotate is determined. This is a case where the pump 8 does not rotate for the time being because the phase angle is not stored before, so that the driving is attempted at α = 98 °. Alternatively, even if the phase angle is previously stored, the sliding resistance is increased due to wear of the sliding portion due to the secular change of the pump 8 or the ambient temperature is further lowered, so that the viscosity of the lubricating oil in the sliding portion is increased. This is the case where the pump 8 cannot be driven and rotated by increasing the phase angle and setting the phase angle. Therefore, after driving again at α = 0 ° and confirming the circulation of bath water by the water flow switch 8 for 10 seconds continuously (S31, S32, YES), the previously stored phase angle value is set to 1 A value down by a step (for example, if α = 90 ° was previously stored, α =
90 ° → 70 °) (S33), and the pump 8 is driven with the updated phase angle setting (S34). That is, the output of the pump 8 is increased by one step as compared with the previous operation, and the operation is performed, and the amount of increase in the sliding resistance is corrected. By doing so, the life of the pump 8 is extended and the effect of increased sliding resistance is reduced. After that, the process proceeds to step 20. Further, if the phase angle is not stored before, and the pump 8 does not rotate even if it is set to α = 98 ° for the time being (S9) and is driven, only one step (α = 98 ° → 95 In some cases, even if the output is increased, the pump 8 does not rotate and the bath water cannot be circulated. That is, when moving from step 34 → 20 → 7, the water flow switch 9 is not turned on in step 7 (S7, NO).
When the time goes to step 30, step 30 → 31
→ 32 → 33 is repeated and α = 98 ° → 95 ° →
The driving power is increased in order at 90 °. And
When the circulating water is confirmed in step 7 (S7, YES), this loop is first exited and the process proceeds to step 20. In this way, the pump 8 determines the minimum voltage (phase angle) that can be rotated, stores the setting of the phase angle at that time, and performs the antifreezing operation based on the stored setting of the phase angle.

In step 3, when the circulation of bath water is not confirmed by the water flow switch 9 (that is, when the bath 4 is not filled with water or hot water), a timer (not shown) is first activated. If that state continues even after 3 minutes have passed (S1
(5, YES) rotates the pump 8 at α = 90 °. In this case, since there is no bath water in the bath 3, there is no circulating water, and the pump 8 idles. The pump 8 is a self-priming pump, which has priming water inside, and even if there is no circulating water, it is necessary to prevent freezing of this priming water. Continue driving. Similarly, when the rise of the ambient temperature is confirmed by the thermoswitch 6 (S11, YES), the operation of the pump 8 is stopped (S12), and the process returns to step 1 (S).
1).

Also, in the processing following step 30 described above, it is conceivable that circulating water may run out. That is, the phase angle is changed in step 30 (α = memorized value →
(0 °) If the bath water circulation is still not confirmed by the water flow switch 8 even after running for 3 minutes at full power (S
31, S29). That is, when the circulating water runs out on the way, the process proceeds to step 10 to idle the pump 8 (S8). In idling, the setting of the phase angle is changed in step 10 (α = 0 ° → 90 °) in order to reduce the noise accompanying the rotation.

According to this bath heater 1, the setting of the pump 8 drive voltage phase angle is gradually changed to determine and store the setting of the phase angle at the minimum voltage at which the circulation of bath water is ensured. Then, by driving the pump 8 with the setting of the stored phase angle, the pump 8 can circulate the bath water with the minimum capacity and perform the operation for preventing freezing. Therefore, it is possible to reduce the noise such as a humming noise that suddenly increases as the rotation speed of the pump 8 and the flow rate of the circulating water increase. Further, the electric power consumed to operate the pump 8 can be minimized.

Even when there is no circulating water, the pump 8 is rotated to prevent freezing of the priming water contained in the pump 8. At this time, instead of full power, the phase angle of the drive voltage is set to a predetermined set value, and operation is performed at a low rotation speed. For this reason, the number of revolutions of the pump 8 does not increase more than necessary, and even in such a case, noise accompanying the revolution can be suppressed. Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can be implemented in various modes without departing from the scope of the present invention. For example, the rotation speed of the pump 8 was changed by changing the setting of the drive voltage phase angle, but unlike this, a DC motor was used as a motor for driving the pump 8, and a pulse generator was provided in the controller.
By adjusting the duty ratio of the pulse signal generated in this pulse generator, the drive voltage of the pump 8 is set to P
You may perform WM control.

[0018]

As described in detail above, the first antifreeze device for a bathtub according to the present invention is necessary because the drive voltage of the pump is reduced when the antifreeze device is operated to rotate. As described above, the number of rotations of the pump does not increase and the flow rate of the circulating water does not increase, so that it is possible to reduce the noise such as a humming noise and it is easy to use. In addition, the pump consumes less power, which is economical.

Further, the second antifreeze device for a bathtub according to the present invention, when the pump is operated to prevent it from freezing, operates by minimizing the number of revolutions of the pump and the flow rate of circulating water, so that a humming noise, etc. The noise can be reduced to a minimum. Therefore, it is very easy to use, the power consumption of the pump is minimal, and it is economical.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an automatic bath heater with hot water supply as one embodiment.

FIG. 2 is a flowchart showing a freeze prevention sequence.

[Explanation of symbols]

 1 Bath Kettle 2 Circulation Heating Circuit 3 Hot Water Supply Circuit 4 Bathtub 5 Remote Controller 6 Thermo Switch 7 Controller 8 Pump 9 Water Flow Switch 21, 31 Heat Exchanger 28, 30 Thermistor 24, 34 Fan 23, 33 Burner

Claims (2)

[Claims] 1. An atmosphere of the circulation circuit, which is used in a forced circulation type bath kettle that circulates bath water in a circulation circuit by a pump and heats the circulation water to return to the bath. When the temperature drops below a predetermined value, in a freeze prevention device that drives the pump to circulate the bath water in the circulation circuit to prevent freeze, the drive voltage of the pump at the time of freeze prevention is set to the circulation heating. An antifreeze device for bath tubs, which is characterized in that it switches so that it will be lower than the maximum voltage during operation. 2. A bathtub antifreezing device according to claim 1, wherein the drive voltage of the pump at the time of the antifreezing is switched to a minimum voltage at which the circulation of the bath water is ensured. Anti-freezing device.