JPH0341737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bathtub water level setting device for automatically stopping water supply (hot water) to a bathtub, such as an automatic bathtub.

(Prior art and problems) Conventionally, in a device that automatically stops pouring hot water or water into a bathtub at a set water level, the detection of the bathtub water level is based on the water level as shown in Utility Model Application No. 169937/1983. This was done by installing a detector in the bathtub.

However, since the set water level was adjusted by changing the spring pressure using a screw, the range of adjustment was limited. For example, the water level difference from the water level detector to the set water level is as much as 200 mm between Japanese baths and Western baths, and in order to satisfy this difference, there are problems such as spring characteristics and large diameter diaphragms, etc. It was difficult to install. In addition, since the water level detector is attached to the bathtub, it is necessary to install a detection cord, and care must be taken to avoid water leakage or breakage of the cord, which is a hassle.

The present invention eliminates the above-mentioned conventional drawbacks, and aims to provide a bathtub water level setting device that can detect the water level outside the bathroom and can easily adjust the set water level over a wide range.

(Example) An example of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram showing an automatic bath pot as an embodiment of the present invention. Reference numeral 1 denotes a main body of an automatic bath device, in which a hot water supply heat exchanger 2 and a bath heat exchanger 3 are built-in. Reference numeral 4 denotes a bathtub installed at a remote location from the device main body 1, and communicates with the bath heat exchanger 3 through a reciprocating pipe consisting of an outgoing pipe 5 and a return pipe 6. A pump 7 is interposed in the middle of the return pipe 6, forming a forced circulation bath circuit A consisting of the return pipe 6, the pump 7, the bath heat exchanger 3, and the outgoing pipe 5. Reference numeral 9 denotes a water level sensor using a diffusion type semiconductor pressure sensor, and in this embodiment, it communicates with the return pipe 6 through a bypass path 10 that is also connected to the upstream side of the pump 7. Reference numeral 8 is a solenoid valve that is opened during an air discharging operation, which will be described later. Reference numeral 25 is a valve that shuts off a flow path between the water level sensor 9 and the pump 7. 24 is a bath adapter, 11 is a water flow switch, and 12 is a hot water temperature sensor. 13 is a water inlet pipe connected to the heat exchanger 12 for hot water supply, 14 is a hot water outlet pipe, and 15 is a bath water supply pipe that branches from the middle of the hot water outlet pipe 14 and faces a hopper 16 open to the atmosphere. 17 is a solenoid valve for automatic hot water supply installed in the hot water supply pipe 15 for the bath, 18 is an outlet hot water temperature sensor, 19 is a water flow sensor installed in the water inlet pipe 13, and 20 is an inlet water temperature sensor. 21 is a float switch that detects the upper and lower limit water levels in the hopper 16, and the hopper 16 is connected to a connecting pipe 2 having a solenoid valve 22 in the middle.
3 to the upstream side of the pump 7 of the return pipe 6.

That is, the water inlet pipe 13, the hot water supply heat exchanger 1
2. Bath water supply pipe 15, hopper 16, connection pipe 2
3 and the like constitute a drop-in hot water supply circuit B, which is connected to the bath circuit A.

Reference numeral 26 denotes a remote controller placed in the bathroom, which is provided with a set water level change switch 27 so that it can be operated in the bathroom when changing the water level after initial setting or canceling the water level setting. Reference numeral 28 denotes a setting section provided in the instrument body 1, which displays a slide switch 29a and a volume 29b for setting the lowest water level (LMIN), and a slide switch 30a, volume 30b, and changeover switch 31 for setting the full water level (LMAX). An LED 32 is arranged as a means.

FIG. 2 is an electrical circuit diagram showing one embodiment of the present invention. 33 is a setting/memory circuit, R1 to R4
Each connection point of the resistor string formed by the volume 3
0b is connected in series with a resistor R0 so that its variable range is the same as the width of one step of the slide switch 30a, and the outputs of the slide switch 30a and volume 30b are connected to an adder 34.
Reference numeral 35 designates the same setting/memory circuit as 33, and the outputs of both circuits are connected to the changeover contact of the changeover switch 31 and to the volume of the set water level change switch 27. 37 is a coincidence detection circuit, and 38 is a display circuit for displaying the detection state of the coincidence detection circuit 37. The coincidence detection circuit 37 has a common contact of the changeover switch 31 connected to a non-inverting input terminal, a first operational amplifier 39 to which the output of the pressure sensor 9 is connected to an inverting input terminal, and an input connected to the first operational amplifier 39 in reverse. A second operational amplifier 40 is provided.
The output of the first operational amplifier 39 is connected to the base of the first PNP transistor 42 via a Zener diode 41 for voltage shifting, and the output of the second operational amplifier 40 is connected to the base of the first PNP transistor 42 via a Zener diode 43.
It is connected to the base of the PNP type second transistor 44. The emitter of the second transistor 44 is connected to the power supply, the collector is connected to the oscillation circuit 45, and the emitter of the first transistor 42 is connected to the second transistor 44.
4, the collector is connected via a diode 46 to the base of a transistor 48 for driving the LED 32. Further, the output of the oscillation circuit 45 is connected to the base of a transistor 48 via a diode 47. 49 is a comparator between the pressure sensor output and the set output.

In the embodiment having the above configuration, a test run is performed upon completion of construction, and the automatic hot water supply stop water level is set. First, hot water is supplied to the bathtub 4, and when the water level reaches the lowest water level (LMIN) at which bathing is possible, the hot water supply is temporarily stopped. At this time, the return pipe 6 and the bypass path 1
The pressure tube consisting of 0 is submerged in water. Set the changeover contact of the changeover switch 31 to the setting/memory circuit 35 side.
The slide switch 29a creates a voltage corresponding to the connected contacts in stages, and the volume 29a
b makes the voltage of one step width variable. Since these two voltages are added by the adder 36, the output of the setting circuit 35 is as shown in FIG. Assuming that the set voltage is lower than the output voltage of the pressure sensor 9,
The second operational amplifier 40 has a high value, cutting off the second transistor 44, and the LED 32 is turned off. Slide switch 29a and volume 29
Operate b to increase the set voltage. When the output voltage of the pressure sensor 9 and the set voltage become close, the output of the second operational amplifier 40 becomes a low value, and when it exceeds the shift voltage of the Zener diode 43, the second transistor 44 is made conductive. On the other hand, the first operational amplifier 39 changes from a low value to a high value, but the first transistor 42 remains conductive until it exceeds the shift voltage of the Zener diode 41. In this state, the transistor 48
Since the base current is always flowing, the LED 32 lights up. When the set voltage is further increased, the first operational amplifier 39 becomes high and the first transistor 42 is cut off. Then, the base current to the transistor 48 is intermittently passed by the oscillation circuit 45.
The LED will blink. Therefore, the set voltage is adjusted while observing the display state of the LED 32, and the slide switch 29a and the volume control 29b are stopped at the lighting position to maintain that state. That is, the output (first set value) of the setting/memory circuit 35 at this time is set to 1V, for example.
Then, the held slide switch 29a,
Depending on the resistance value of volume 29b, even after setting operation.
1V is continuously output, so the first
This means that the setting value has been memorized. By this operation, even if there is a vertical difference between the position of the bathtub 4, that is, the opening position of the pressure detection tube, and the pressure sensor 9, this difference will be adjusted. Next, supply hot water to the full water level (LMIX), turn the changeover switch 31,
Perform the same operation as above to set the full water level. That is, the second set value is stored. in this way,
The slide switches 29a, 30a and the volumes 29b, 30b constitute setting means for outputting variable set values, and at the same time constitute storage means for storing the set values. Then, the value obtained by dividing both the first set value and the third set voltage by the bathtub water level change switch 27 (second setting means) is the second set value that becomes the drop stop water level. That is, for example, the first set value is 1V, the third
The setting value is 4V, and the bathtub water level change switch 2
7 divides the resistance value at a ratio of 1:2, the second set value is 3V. Therefore, the second
The setting means outputs a first set value (here, 1V) and a second set value (here, 3V) as a reference. Consider a case where the bathtub is located higher than in this example, and assume that the first set value is 2V. Naturally, the position of the full water level also changes and becomes 5V.
Then, the bathtub water level change switch 27 changes the resistance value to 1:
If the voltage is divided into 2, the second set value will be 4V.
In other words, as in the previous example, using the first set value as the standard,
A voltage higher by 2V becomes the output of the second setting means. This voltage difference of 2V corresponds to the difference between the water level corresponding to the first set value and the water level corresponding to the second set value. Therefore, if you change the output of the second setting means, the water level corresponding to the second set value will change, and the difference between the set water levels of Japanese bass and Western bass, 200
Approximately mm can be sufficiently changed. The output (partial pressure value) of this second setting means is the reference input of the comparator 49 that determines whether or not the drop is stopped. In other words, when the output value of the pressure sensor and the partial pressure value match, the comparator 49 issues a hot water supply stop signal.

Incidentally, the water level may be set only at the full water level, or the bathtub water level change switch 27 may also be omitted.

Next, the operation of the automatic bathtub during automatic hot water supply after the settings have been made during the test run will be described. It is necessary to exhaust the air in the path from the water level sensor 9 to the bathtub 4, that is, the piping from the bypass path 10 to the bathtub 4 via the return pipe 6. For this purpose, with the solenoid valves 22 and 25 closed, the automatic hot water supply solenoid valve 17 is opened and the hot water supply heat exchanger 2 is connected to the hopper 16.
Supply heated hot water. When the water level in the popper 16 reaches the upper limit, the float switch 21 detects this and closes the automatic hot water supply solenoid valve 17, opens the solenoid valve 22 and the solenoid valve 8, and operates the pump 7. Then, the hot water in the hopper 16 mainly flows from the connecting pipe 23 via the pump 7 to the bypass path 10 with low water flow resistance. This is because the bath heat exchanger 3 has a pipe wound around the outer periphery of the heating cylinder and a fin pipe-shaped heat absorbing part formed inside the heating cylinder, so it has many bent parts and the water flow resistance is extremely large. Therefore, the hot water discharged from the pump 7 reaches the bath heat exchanger 3 and then flows to the side of the bypass passage 10 where water flow resistance is small. The hot water flows backward through the water flow switch 11 from the bypass path 10, passes through the return pipe 6, and heads toward the bathtub 4. When the water level in the hopper 16 reaches the lower limit, the float switch 21 detects this and stops the pump 7, closes the solenoid valve 22 and the solenoid valve 8, and opens the automatic hot water supply solenoid valve 17. In this way, hot water is again supplied to the upper limit water level of the hopper 16 and sent to the return pipe 6 via the bypass path 10. By repeating the above operations multiple times, the bypass passage 10 and return pipe 6 are filled with hot water, and air is discharged from the bath adapter 24. The number of times to repeat varies depending on the construction site depending on the length of the piping, etc., so the above is determined during the trial run and stored in the controller.

Incidentally, a water flow rate sensor may be provided in the hot water supply pipe 15 or the connecting pipe 23 for the bath to measure the flow rate necessary for discharging the air. The use of the hopper 16, which is essential for preventing the risk of water flowing back into the city water pipe through the route, eliminates the waste of using expensive water flow sensors.

When the air exhaust operation is performed a predetermined number of times and the path from the water level sensor 9 to the bus adapter 24 is filled with hot water, the solenoid valve 8 is closed and the output of the water level sensor 9 is sampled. This air exhaust operation is always performed at the beginning of automatic hot water supply, so if there is hot water remaining in the bathtub 4 and the set water level has already been reached at this point, automatic hot water supply will be stopped, but if not, Opens the automatic hot water supply solenoid valve 17 and the solenoid valve 22, operates the pump 7, and supplies hot water along the route from the outgoing pipe 5 to the bathtub 4 through the bath heat exchanger 3. While hot water is being supplied through this route, the output of the water level sensor 9 is sampled, and the hot water that was filled in the return pipe 6 until the water level in the bathtub 4 reaches the bath adapter level (LBA) is There is a risk that the water may be replaced by air entering from the bus adapter 24, and if air is present in the pipe, the water level sensor 9 will not be able to accurately detect the water level, so at least the water level sensor 9
Until the output confirms that the water level in the bathtub 4 has exceeded the bath adapter level (LBA), the solenoid valve 8 is opened at regular intervals to supply hot water to the return pipe 6 via the bypass path 10. That is, hot water is sent out alternately from the outgoing pipe 5 side and the return pipe 6 side. However, when the solenoid valve 8 is opened and hot water is supplied from the return pipe 6 side, the discharge pressure of the pump 7 is transmitted to the water level sensor 9, so the output of the water level sensor 9 is not sampled, and therefore hot water is supplied from the return pipe 6 side. The time is kept as short as possible. Since the valve 25 and the solenoid valve 8 are closed while hot water is being supplied from the outgoing pipe 5 side, neither the suction pressure nor the discharge pressure of the pump 7 is applied to the water level sensor 9, and only the pressure due to the water level of the bathtub 4 is applied to the water level sensor 9. Yes, and its output can be sampled continuously. That is, the bypass path 10 and the return pipe 6 serve as a pressure detection pipe.

The output of the water level sensor 9 is compared by a comparator 49 with an output value (PSET) corresponding to a set water level arbitrarily set between the minimum water level (LMIN) and the full water level (LMAX), and the output value (PSET ) When the output above is detected, the automatic hot water supply solenoid valve 17 and the solenoid valve 22 are closed and the pump 7 is stopped.

In this way, hot water can be automatically supplied to the bathtub 4 at a remote location up to the desired water level, regardless of whether or not there is hot water remaining in the bathtub 4 before automatic hot water supply starts, and even if air has entered the piping at the beginning. It can also be stopped at the desired water level with great precision.

Incidentally, in order to reheat the hot water in the bathtub 4, the valve 25 is opened and the pump 7 is operated. The bath water sucked in from the return pipe 6 is heated by a bath heat exchanger 3 which is heated by a signal from the water flow switch 11, and then reaches the bathtub 4 from the outgoing pipe 5, where the water temperature sensor 12 detects a preset temperature. This cyclic heating is then automatically stopped. In addition, since the valve 25 is open during this reheating, the water level sensor 9 is connected to the pump 7.
The water level is not detected because it is affected by the suction pressure.

(Effects of the Invention) As described above, the present invention uses a semiconductor pressure sensor to detect the water level, so the detection output can be extracted as an analog electrical signal, which is convenient when the output is used for control, and can be used over a wide range of applications. Output can be obtained according to the water level difference. Also, when installing a water level detector outside the bathroom, unlike the conventional case where a water level detector is installed in a bathtub, the height relationship between the bathtub and the water level detector cannot be seen at a glance, making it difficult to install. However, in the present invention, the height relationship between the water level detector and the opening position of the pressure tube is first adjusted.
By adjusting the setting means, the water level detector can be installed outside the bathroom without having to perform difficult level adjustment. Therefore, there is no need to install the water level detector cord inside the bathroom.

Furthermore, since the setting from the opening position of the pressure test tube to the dropping stop water level is performed by the second setting means,
The height from the water level detector to the drop stop water level is 2
This means that the resolution of the setting means is improved compared to the case where one setting means covers everything from the water level detector to the dropping stop water level.

Further, as in the embodiment, by setting the water level using a coarse adjustment slide switch and a fine adjustment volume, it is possible to set the water level at any point. Moreover, since the settings are extracted as electrical signals, the initial settings can be easily changed in the bathroom. This is useful when the builder's settings and the user's settings do not match. If the setting is made at two points, the resolution when changing the setting becomes finer, and the volume can be adjusted sufficiently without providing a rough adjustment resistor. Furthermore, by using a slide switch and a volume, the setting means and storage means can be used both, and the circuit configuration can be simplified.

Further, by providing a coincidence detection means for detecting coincidence between the setting output and the sensor output, and a display means for displaying the detection state of the coincidence detection means, the operation of the setting means becomes even easier.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an automatic bath pot according to the present invention. FIG. 2 is an electric circuit diagram of one embodiment of the present invention, and FIGS. 3 and 4 are operation explanatory diagrams. 4... Bathtub, 6... Return pipe, 10... Bypass path, 9... Semiconductor pressure sensor, 33, 35... Setting/memory circuit.

Claims (1)

[Claims] 1. A pressure detection tube that communicates with the bathtub and is led out of the bathroom, a semiconductor pressure sensor installed in the pressure detection tube, and a first setting means that outputs a variable set value;
a first storage means that stores the set output as a first set value when the set output matches the sensor output when the pressure test tube is submerged; and a second storage means that outputs a variable set value based on the first set value. and a second storage means for storing the set output of the second setting means as a second set value, and the second set value is used as the drop stop water level. Water level setting device.