JPH037860B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a freezing prevention control device for an automatic bathtub.

(Prior art) In conventional automatic bathtubs, when a phenomenon occurs during automatic operation, such as switching from automatic operation to reheating mode, resetting operation due to entry into safety operation, operation stoppage due to momentary power failure, operation switch off, etc., the drop-in hopper is activated. Even if the outlet was closed and water remained inside, the hopper could not be drained unless a separate drainage operation was performed. (Unexamined Japanese Patent Publication No. 61-101744, Utility Model No. 61-69764
No.) Because of this, the water remaining in the hopper freezes,
You may not be able to drop it into the bathtub the next time you use it.

In addition, in oil appliances that are often used in particularly cold regions, water is drained manually, but the next time the appliance is used, water may leak due to forgetting to turn off the valve, or the appliance may be left unheated due to forgetting to open the valve. Furthermore, if draining is forgotten, equipment damage may occur due to residual water freezing.

In order to prevent such freezing accidents, it is possible to prevent freezing of the automatic water supply pipeline including the dropping hopper using a heater, but in this case, a considerable amount of equipment is required and running costs are also high.

(Object of the Invention) The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide a freezing prevention control device for an automatic bath pot that prevents freezing accidents caused by residual water in the dropping hopper. shall be.

(Structure of the Invention) In order to achieve the above-mentioned object, the automatic bath pot freeze prevention control device according to the present invention includes a hopper for dropping hot water, and a switching valve installed in the circulation path to switch between the dropping side and the circulation side. , a residual water detection means for detecting the presence or absence of residual water in the hopper, characterized in that a control means is provided for switching the switching valve to the drop-in side when residual water is detected by the residual water detection means. be.

(Example) Hereinafter, the present invention will be specifically described based on illustrated examples.

In the figure, 1 is the can body, 2 is the burner controller, 3
4 is a bathtub, and 4 is a circulation pump installed in the circulation path.
5 is a switching valve provided in the circulation path, 5a is a drop-in side inlet of the switching valve 5, 5b is a circulation-side inlet of the switching valve 5,
6 is a heat exchanger for the bath, 7 is a hopper for dropping hot water, and 8 is a float switch for detecting the water level of the hopper 7. 9 is a drop valve, 10 is a controller, and 11 is an operation switch. Figure 2 is an electrical circuit diagram, 12 is a control power supply, 13, 14, 1
9, 20, 22-24, 26-28 are resistors. 15 is an IC (microcomputer, 16, 17, 21, 3
0 and 31 are diodes. 18 is a control power supply;
25 is a capacitor, and 29 is a transistor.
32 is a drive relay for the circulation pump 4, 33 is a drive relay for the switching valve 5, and 34 is a drive relay for the drop valve 9. 35 to 37 are ICs (output drivers),
38 is a voltage comparator.

In the above configuration, for example, when automatic hot water supply ends by closing the dropping valve 9 under the control of the controller 10, when the operation mode is switched to OFF and the operation switch 11 is switched to OFF, the residual water detection means If there is residual water in the hopper 7, the float switch 8 transmits a residual water detection signal to the controller 10, the switching valve 5 is switched to the drop-in side inlet 5a, and the circulation pump 4 is switched to the drop-in side inlet 5a.
is activated and the remaining water is guided to the bathtub 3. When the remaining water disappears and the float switch 8 is turned off, the switching valve 5 is switched to the circulation side inlet 5b, and the hopper 7
The outlet of the pump is blocked, and the circulation pump 4 is also stopped.

That is, in the controller 10, the operation switch 11
is on, the residual water detection state of the float switch 8 is input as a low value signal to the IC (microcomputer) 15 via the resistors 13 and 14 and the diode 16, and each IC is controlled according to the control sequence built into the microcomputer 15. The load drive relays 32 to 34 that drive the circulation pump 4, the switching valve 5, and the dropping valve 9 are controlled via (drivers) 35 to 37. At this time, the voltage comparator 38 has a voltage divided by the resistors 19, 20 and diodes 17, 21 (negative phase input of the voltage comparator 38) which is larger than the voltage divided by the resistors 22, 23 (positive phase input of the voltage comparator 38). Therefore, transistor 29 is off.

On the other hand, when the operation switch 11 is turned off while the float switch 8 is in the residual water detection state, the negative phase input of the voltage comparator 38 is divided by the resistors 19, 24 and 17, and becomes smaller than the positive phase input of the voltage comparator 38. The output of the voltage comparator 38 becomes a high value, and the resistor 26
In order to turn on the transistor 29 via the diodes 30 and 31, the drive relay 32 that drives the circulation pump 4 and the drive relay 33 that drives the switching valve 5 are driven, and the switching valve 5 is switched to the drop-in side outlet 5a. At the same time, the circulation pump 4 is started and water is drained from the hopper 7 until the voltage comparator 38 is turned off. By draining water from the hopper 7, freezing accidents caused by residual water in the hopper can be prevented.

In this embodiment, when the operation switch 11 is on, the output of the voltage comparator 38 and the transistor 29 are turned off to prevent drainage operation, so automatic operation, reheating operation, etc. can be freely performed by microcomputer software processing. , it is possible to prevent operation commands from intersecting. This is particularly effective when the operation switch 11 is not mechanically held but electrically held.

(Effects of the Invention) As described above, according to the present invention, when a safe operation occurs during automatic hot water supply, when the operation mode is changed, when the operation switch is turned off after recovery from a momentary power failure, etc.
When the dropping residual water detecting means detects that there is residual water in the hopper, the control means opens the valve that opens and closes the outlet of the dropping hopper and drains the hopper, so that the residual water in the hopper is removed. It is possible to reliably prevent freezing accidents caused by

[Brief explanation of the drawing]

FIG. 1 is an overall diagram showing an embodiment of the present invention, and FIG. 2 is an electric circuit diagram of the present invention. 4...Circulation pump, 5...Switching valve, 7...Hopper, 8...Float switch.

Claims (1)

[Claims] 1. A device comprising a hopper for dropping hot water, a switching valve installed in the circulation path to switch between the dropping side and the circulation side, and a residual water detecting means for detecting the presence or absence of residual water in the hopper, in which the above-mentioned residual water detecting means is used. A freezing prevention control device for an automatic bath pot, characterized in that a control means is provided for switching the switching valve to the drop side when residual water is detected.