JPH083761B2 - Hot water mixing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot and cold water mixing apparatus for supplying hot water by mixing hot water and water to obtain an appropriate temperature.

2. Description of the Related Art Conventionally, this kind of hot and cold water mixing device has been shown in FIG. (For example, Japanese Utility Model Laid-Open No. 55-59223) In FIG. 3, inside a valve frame body 4 having an inlet 1 for hot water, an inlet 2 for water, and an outlet 3 for mixed hot water, a hot water valve 5 and a water A side valve body 6 is provided. The hot water valve body 5 and the water side valve body 6 are attached to a shaft 7, and are driven by a motor 10 via a linear operation conversion mechanism 8 and a gear 9 provided outside. A mixed hot water temperature detector 11 for detecting the mixed hot water temperature is provided in the vicinity of the mixed hot water outlet 3.
The controller 13 compares the mixed hot water temperature value set by the mixed hot water temperature setting device 12 with the hot water temperature value detected by the mixed hot water temperature detector 11, and controls the motor 10. The terminal is provided with a faucet 14 for supplying mixed hot water. Then, when the faucet 14 is opened and the mixed hot water temperature setting device 12 provided at a remote place is manually operated to set the mixed hot water temperature, the controller 13 causes the value of the mixed hot water temperature detector 11 and the mixed hot water temperature setting device 12 to be set. Are compared, and the motor 10 is drive-controlled so as to eliminate the temperature deviation between the two.

Problems to be Solved by the Invention However, the above configuration has the following problems.

(1) Unless the water pressure and water pressure are completely equal pressure, when the faucet 14 is closed, resistance is added by the faucet 14 and the pressure at the outlet 3 of the mixed hot water rises, and the hot water inlet 1 And water inlet 2
In some cases, the pressure difference between the two decreased and a so-called "pressure loss" phenomenon occurred, and hot water or water was mixed from the high pressure side to the low pressure side. For this reason, there was a phenomenon that hot water came out at the other tap even though it was supposed to be water, or water came out when it was supposed to be hot water.

(2) Under the condition that the water pressure is higher than the hot water pressure, water is mixed into the hot water side when the faucet 14 is closed, and water also comes out from the hot water side when the hot water supply is restarted. The temperature to be set becomes much lower than the temperature set by the mixed hot water temperature setting device 12.
For this reason, the controller 13 rapidly opens the hot water valve body 5 and quickly closes the water water valve body 6, so that the water flowing backward is pushed out and the hot water comes out continuously, and the mixed hot water temperature becomes excessive. It was dangerous as it descended to and then rose.

(3) Since it is an electric type and the mixed hot water temperature setting device 12 is provided at a remote location, there are few users near the faucet 14 when the water is cut off, and the mixed hot water and dirty water may flow back.

As a countermeasure against this, it may be possible to install a backflow stop valve at the hot water inlet 1 and the water inlet 2. However, if the faucet 14 is slowly closed or the hot water is discharged at a small flow rate, the pressure of the hot water and the water will be high or low. This causes a difference in the operation of the check valve, which causes a problem. For example, when the hot water pressure is low and the water pressure is high, the closing force of the check valve is constant, so if the hot water side is closed first and the water side is closed late, or if it is left with a small flow rate, Sometimes only the side continues to flow. For this reason, the temperature of the mixed hot water temperature detector 11 decreases, and the controller 13 causes the hot water valve body 5 to move toward the opening direction.
Controls to move in the closing direction. If the faucet 14 is reopened under such a situation, the temperature of the mixed hot water excessively falls and rises, which is dangerous as in the above-mentioned item (2). The same problem occurs when opening slowly.

The present invention solves such a conventional problem, and provides a hot and cold water mixing apparatus that prevents excessive fluctuations in the mixed hot water temperature and backflow, which are problems peculiar to an electrically controlled hot and cold water mixing apparatus. The purpose is to

Means for Solving the Problems To achieve this object, the hot and cold water mixing apparatus of the present invention comprises:
A hot water check valve in the hot water flow path, a hot water check valve in the hot water flow path, a hot water mixing valve that adjusts the mixing ratio of hot water and water, and a mixing valve that electrically drives this hot water mixing valve. A driving means, a mixed hot water flow path through which the mixed hot water flows, a flow control valve for supplying and stopping the mixed hot water, and a flow control valve driving means for driving the flow control valve,
Mixing hot water temperature setting device for setting the mixed hot water temperature, hot water supply setting device for setting the start / stop of the mixed hot water supply, and controlling the mixing valve drive means according to the setting of the mixed hot water temperature setting device, and setting of the hot water setting device The flow control valve driving means is controlled in accordance with the above, and when the hot water supply is started or stopped, the flow control valve is not continuously stopped in a predetermined small flow rate range, and when the hot water pressure and the water pressure are unequal, the mixed hot water channel has a predetermined value or more. And a controller that opens and closes within a time period when the hot water is removed.

Operation With the above-mentioned configuration, when the hot water supply is started or stopped, the flow control valve is not continuously stopped in a predetermined small flow rate range, and the flow rate of the mixed hot water flow is set to a predetermined value when the flow pressure control valve has an unequal pressure. It is controlled so that it opens and closes within the time filled with the mixed hot water that is not above, and the mixed hot water temperature drops excessively due to the imbalance of the operation of the hot water check valve and the hot water check valve. By the action of the valve and the water-side check valve, imbalance of hot water pressure and water pressure, mixing of hot water and water at the time of water interruption, and backflow are prevented.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, a hot water side check valve 18 is provided in a hot water side flow passage 17 and a hot water side flow passage is provided in a valve frame body 16 of a valve unit 15 of the hot water mixing apparatus.
A water side check valve 20 is provided at 19. This hot water check valve 18
Each of the water side check valve 20 and the water side check valve 20 includes a check valve body 21 having a packing, a valve seat 22 and a spring 23 for urging the check valve body 23 in a closing direction. A pressure balance valve 24 that equalizes the pressures of the hot water and the water is provided downstream of the check valves 18 and 19, and the hot water and the water whose pressures are equalized function as a mixing valve and a flow control valve. It is introduced into the side valve 25 and the water side valve 26. Both the hot water valve 25 and the hot water valve 26 have a valve seat 28 and a valve body 28 having a packing.
And a shaft 29 connected to the valve body.

Both the hot water valve 25 and the hot water valve 26 are driven by a hot water motor 30 and a hot water motor 31 provided outside through a reduction gear 32 and a linear motion conversion mechanism 33, and the hot water and hot water mixing ratio is increased. And the flow rate are adjusted. The temperature of the mixed hot water mixed is detected by the thermistor 35 provided in the hot water flow passage 34, and the flow rate is detected by the flow rate sensor 36. The mixed hot water is supplied from the hot water supply port 37 to the hot water supply target, and a setting device 38 is provided in the vicinity thereof. In the setting device 38, a switch (1) 39 for starting and stopping the supply of the mixed hot water and supplying the hot water at a predetermined mixed hot water temperature and flow rate, and a preset mixed hot water temperature and flow rate for the supply of the mixed hot water are set. The switch (2) 40 that stops hot water supply when hot water is supplied to reach a predetermined integrated flow rate, the switch (3) 41 that lowers the temperature by changing a predetermined value of the mixed hot water temperature, the switch (4) 42 that raises the temperature, and the mixing A display unit 43 for displaying the temperature and flow rate of hot water is provided. Thermistor 35, Flow sensor 3
6. The signal from the setting device 38 is transmitted to the controller 44, and the controller 44 controls the hot water motor 30, the water motor 31, and the display unit 43. FIG. 2 shows an example in which the hot and cold water mixing apparatus of this embodiment is attached to a hot water supply system.
Water is supplied by branching from 46, and the boiled hot water is the hot water supply pipe 47
And is supplied to the valve unit 15 via. Further, water is supplied to the valve unit 15 via a water supply pipe 48 branched from the water supply 46. The mixed hot water is supplied to the bathtub 49 which is a hot water supply target. Further, a gas pipe 50 for supplying hot gas of gas is connected to the gas instantaneous water heater 45. When constructing this system,
It often happens that the gas pipe 50 and the hot water supply pipe 47 or the water supply pipe 48 are installed by mistake. And hot water supply pipe 47 or water supply pipe
Although gas is ejected from the valve unit 15 via the valve unit 15 at the time of initial operation and fills the bathroom in which the bathtub 49 is placed, it is dangerous, but in this embodiment, a countermeasure against this is taken. That is, the set load of the spring 23 of the hot water check valve 18 and the hot water check valve 20 is increased,
The check valves 18 and 20 are designed so that they do not open under the pressure of gas. The gas pressure of propane gas is higher than that of city gas, and the standard is 280 mm faucet. Assuming that the effective pressure receiving area of the check valve body 21 of the check valves 18 and 20 is 2 cm ² , this is about 56 g.
Equivalent to the power of. Therefore, if the set load of the spring 23 is set higher than this, it is possible to prevent gas ejection at the time of erroneous piping.

When the switch 39 of the setting device 38 is pressed by the above-described configuration, the hot water side motor 30 and the water side motor 31 open the hot water side valve 25 and the water side valve 26 via the controller 44. Then, the controller 44 monitors the signal of the flow rate sensor 36 and increases the opening degree until the mixed flow rate set in advance corresponding to the switch (1) 39 is obtained. At the same time, the controller 44 controls the mixed hot water temperature detected by the thermistor 35 and the mixed hot water temperature corresponding to the switch (1) 39.
In comparison, the opening speeds of the hot water side motor 30 and the hot water side motor 31 are adjusted to obtain the set mixed hot water temperature. The controller 44 corrects the mixing ratio by detecting the mixed hot water temperature with the thermistor 35 against the disturbance such as the hot water temperature or the fluctuation of the water temperature which is normally supplied. When the other tap branched from the hot water supply pipe 47 or the water supply pipe 48 is used and the hot water pressure or water pressure fluctuates, the pressure balance valve 24 functions to balance the pressure of hot water and water and prevent the fluctuation of the mixed hot water. There is. When it is desired to stop the supply of the mixed hot water, when the switch (1) 39 is pressed again, the hot water side valve 25 and the water side valve 26 are closed and the supply of the mixed hot water is stopped. Since the pressure balance valve 24 is provided on the upstream side of the hot water valve 25 and the hot water valve 26, the mixed hot water temperature normally does not change even if the hot water pressure and the water pressure fluctuate, but the pressure balance valve 24
In case of sticking, the hot water pressure and the water pressure are directly applied to the hot water valve 25 and the hot water valve 26.

If, in this state, the hot water valve 25 and the water valve 26 are closed very slowly, the hot water check valve 18 and the hot water check valve 18 are closed as the hot water valve 25 and the hot water valve 26 are closed. The pressure before and after the check valve body 21 of the water side check valve 20 gradually decreases. When the acting force of the fluid acting on the check valve body 21 becomes equal to or less than the set weight of the spring 23, the check valve body 21 comes into contact with the valve seat 22 and the flow stops. In this case, the smaller the pressure of the hot water or water, the faster the decrease in the flow rate, so that the flow stops early. If the operations of the hot water valve 25 and the hot water valve 26 are stopped in such a small flow rate range, for example, when the water pressure is smaller than the hot water pressure, the hot water flow path 34 is filled with hot water and eventually Hot water is supplied from the hot water supply port 37. If the water pressure is lower than the water pressure, only water is supplied. The same is true at the time of opening.

In order to prevent such a phenomenon, in this embodiment, when the hot water supply is started or stopped, the hot water valve 25 and the hot water valve 26 are not continuously stopped in a predetermined small flow rate range, and the hot water pressure and the water pressure are unequal pressure. At times, the hot water valve 25 and the hot water valve 26 are quickly opened and closed within a time period when the hot water mixing passage 34 is filled with the hot water that has deviated by a predetermined value or more. Therefore, when the supply of the mixed hot water is stopped at the start, the hot water side check valve 18 and the water side check valve 20 are opened and closed with a large time difference, or one of them is closed and the other is left open. That situation does not occur. Therefore, the setting device is
There is no intervening hot water with a temperature that greatly deviates from the mixed hot water temperature set in 38, and there is no danger that the hot water temperature will drop or rise during use. Also, usually the water pressure,
Even if the water pressure is not equal, the pressure balance valve 24 suppresses the fluctuation of the mixed hot water temperature, and the hot side valve 25 and the water side valve 26 are closed or the high pressure side is mixed with the low pressure side during closing. It can be prevented by the functions of the hot water check valve 18 and the water check valve 19. Further, for example, even when the setting device 38 is installed in a remote place, the check valves 18 and 19 function to prevent backflow of mixed hot water and dirty water when water is cut off. Further, when the water is cut off, the signal from the flow rate sensor 36 can be used to close the hot water valve 25 and the water valve 26 to prevent double backflow.

In this embodiment, the hot water side valve 25 and the hot water side valve 26, which also serve as the hot and cold water mixing valve and the flow rate control valve, are driven by the hot water side motor 30 and the water side motor 31 which are independent electric drive means. The structure that can have both the mixing and flow rate control functions is simplified, the hot water side and the water side can be configured with the same parts, and when hot water supply is stopped, the flow path is closed and the reverse flow prevents the hot water side valve 25.
Since it can also be prevented by the water side valve 26, it is effective in terms of the structure and ensuring the backflow prevention. In addition, the hot water check valve 18 and the water check valve
Since the spring 23 of 20 is set to a set load that cannot be opened by gas pressure, even if the hot water supply pipe 47 or the water supply pipe 48 is connected to the gas pipe 50, there is no risk of gas spouting and safety. It is effective in terms of aspects.

In this embodiment, the feedback control method in which the mixed hot water temperature is detected by the thermistor 35 and compared with the set value of the setter 38 is taken as an example, but the hot water temperature and the hot water flow rate or the hot water temperature and the water flow rate are measured beforehand. The idea of the present invention can also be applied to feedforward control for calculating and controlling the mixed hot water temperature, a control system using both feedforward control and feedback control, and the like. Further, in the present embodiment, the hot and cold water mixing valve and the mixing valve drive means include a hot water side valve 25 and a water side valve 26 which are independently provided on the hot water side and the hot water side, respectively.
Although the method of driving by 31 is taken as an example, the hot and cold water mixing valve and the mixing valve driving means may be separated literally. Further, a system in which a hot water mixing valve whose temperature is controlled by a wax thermoelement or a bimetal is driven by an electric driving means may be adopted.

Effects of the Invention As described above, according to the hot and cold water mixing apparatus of the present invention, the following effects can be obtained.

(1) Even if the hot water pressure and the water pressure are unequal, no hot water or water mixes from the high pressure side to the low pressure side, and even if the mixed hot water temperature setting device is installed at a remote location, the mixed water is cut off. It is safe and sanitary without backflowing sewage and sewage.

(2) Hot water pressure, mixed hot water supply starting when water pressure is unequal pressure, excessive decrease of mixed hot water temperature at stop, rising or returning to an uncontrollable state when left at a small flow rate or proper flow rate Fluctuations in the temperature of the mixed hot water do not continuously stop the flow control valve in the predetermined small flow rate range, and the mixed hot water passage is filled with the mixed hot water that deviates from the predetermined value or more when the hot water pressure and the water pressure are unequal. It is prevented by opening and closing within the time.

(3) The flow control valve can automatically close the flow path when water is cut off, and double backflow can be prevented together with the hot water check valve and the water check valve.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view of a hot and cold water mixing apparatus according to an embodiment of the present invention, and FIG. 2 is a hot water supply system diagram using the apparatus.
FIG. 3 is a block diagram of a conventional hot and cold water mixing apparatus. 17 …… Hot water side flow path, 18 …… Hot water side check valve, 19 …… Water side flow path,
20 …… Water side check valve, 25 …… Hot water side valve (hot water mixing valve, flow control valve), 26 …… Water side valve (hot water mixing valve, flow control valve), 30
...... Hot water side motor (mixing valve drive means, flow rate control valve drive means), 31 ...... Water side motor (mixing valve drive means, flow rate control valve drive means), 34 ...... Mixed hot water flow path, 38 ...... Setting device (Mixed hot water temperature setting device, hot water supply setting device), 44 ... Controller.

Claims (3)

[Claims] 1. A hot water check valve provided in a hot water flow path, a water check valve provided in a hot water flow path, a hot and cold water mixing valve for adjusting a mixing ratio of hot water and hot water Mixing valve drive means for electrically driving the valves, a mixing hot water passage through which the mixed hot water flows, a flow control valve for supplying and stopping the mixed hot water, a flow control valve driving means for driving the flow control valve, The mixed hot water temperature setting device for setting the hot water temperature, the hot water supply setting device for setting the start / stop of the supply of the mixed hot water, the mixing valve drive means according to the setting of the mixed hot water temperature setting device, and the hot water supply setting device Control the flow control valve drive means according to the setting of, to start hot water supply,
Without stopping the flow control valve continuously in a predetermined small flow rate range at the time of stoppage, and when the hot water pressure and water pressure are unequal, the hot water flow passage is opened and closed within a time period when the hot water flow is filled with hot water that deviates from the predetermined value or more. A hot and cold water mixing device equipped with a controller. 2. A hot and cold water mixing valve and a mixing valve driving means, and a flow rate control valve and a flow rate control valve driving means, wherein the hot water side valve and the water side are the mixing valve and the flow rate control valve which are independently provided on the hot water side and the water side, respectively. The hot and cold water mixing apparatus according to claim 1, wherein the valves are driven by independent hot water side driving means and water side driving means, respectively. 3. The hot and cold water mixing apparatus according to claim 1, wherein the hot water check valve and the hot water check valve are configured so as not to be opened by the pressure of the gas.