JP2615059B2 - Hot water mixing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field The present invention relates to a hot and cold water mixing apparatus characterized in that the temperature of mixed hot and cold water is controlled by detecting the pressure of a hot water side flow path / water side flow path. About.

(B) Conventional technology The mixing temperature constant control of the conventional hot water mixing device is as follows.
As shown in FIG. 8, a flow sensor 2 and a temperature sensor 3 are provided after the temperature control valve 1, and a feedback signal is supplied from the flow sensor 2 and the temperature sensor 3 to the controller 4 in order to keep the temperature of the mixed hot and cold water constant. Temperature control valve 1
The motor is driven by PID control to perform constant temperature control.

In the figure, reference numeral 5 denotes an operation panel for operating the controller 4,
Reference numeral 6 denotes a flow control / water stop / switch valve that is disposed upstream of the temperature control valve 1 and selectively supplies mixed hot water to the discharge fitting channel 7 and the shower channel 8.

(C) Problems to be Solved by the Invention However, as in the conventional method, the temperature control valve 1
In the method of sensing the temperature by the downstream temperature sensor 3 and then controlling the temperature, the primary side, that is, when the water pressure fluctuation of the hot water side flow path 9 or the water side flow path 9a upstream of the temperature control valve 1 suddenly occurs. Response delay due to the distance from the temperature control valve to the temperature sensor position (about 0.1 second), Response delay of the temperature sensor (about 0.5 to 1 second), Response delay of motor and transmission system play (about 0.1 second), etc. There was a delay, and the operation of the control system was delayed for a total of about 0.7 to 1.2 seconds.

Therefore, inevitably, when the pressure fluctuates, as shown in FIG. 9, the overshoot Δ of the tapping temperature from the set temperature Ts.
To and undershoot Δtu have occurred, which has caused the user to feel uncomfortable. In addition, fluctuations in water pressure and hot water pressure tend to occur more frequently than fluctuations in water temperature and hot water temperature, and there has been a problem in dealing with such pressure fluctuations.

The response delay is as close as possible to the temperature sensor mounting position of the temperature sensor. The response delay is the physical property value of the temperature sensor. For the delay, countermeasures such as a structure having as little clearance as possible can be considered, but the above-described response delay is the smallest value in the current technology.

In recent years, as described in Japanese Patent Application Laid-Open No. 61-278679, the primary pressure between the hot water side and the water side is reduced by a hot water mixing apparatus, and the secondary pressures of the hot water side and the water side after the pressure reduction are reduced. Although there is a pressure adjusting valve provided to make the pressure equal, the hot water mixing apparatus has a complicated mechanism and has a large overall structure. Further, since either the water side pressure or the hot water side pressure is reduced to equalize the secondary pressure, a large flow rate cannot be obtained even if the pressure on one side is very high.

Further, in a separately devised hot and cold water mixing device, a plurality of gains for determining a valve opening / closing speed are stored in a memory, and an optimum gain is determined from the memory according to a deviation between the mixed hot and cold water temperature and a set temperature. It was decided to determine the valve opening and closing speed.

However, even in such hot water mixing control, the response speed is slow, and the above-described overshoot and undershoot cannot be effectively prevented.

An object of the present invention is to provide a hot and cold water mixing control device that can solve the above problems.

(D) Means for Solving the Problems The present invention relates to a hot water mixing apparatus in which a hot water side flow path and a water side flow path are connected to a mixed hot water flow path through a temperature control valve that varies a hot water / water mixing ratio. A pressure sensor that detects a water pressure of at least one of the hot-water flow path and the water-side flow path; a temperature sensor that is provided in the mixed hot-water flow path and detects the temperature of the mixed hot water; And a controller for controlling a temperature of the mixed hot water by changing a mixing ratio of the hot and cold water by driving a temperature control valve in accordance with a detection output of the temperature sensor.

The present invention also provides a hot water mixing apparatus in which a hot water side flow path and a water side flow path are connected to a mixed hot water flow path through a temperature control valve that varies a hot water / water mixing ratio. A pressure sensor for detecting a pressure difference between the flow path and the mixed hot and cold water flow path, and control for controlling a temperature of the mixed hot and cold water by changing a mixing ratio of the hot and cold water by driving a temperature control valve based on a detection output of the pressure sensor. It is also characterized by having a container.

(E) Function and Effect With the above-described configuration, the present invention has the following effects.

A pressure sensor for detecting the pressure on the hot water supply side and / or the water supply side is provided upstream of the temperature control valve, so that the operation delay of the control system at the time of pressure fluctuation can be eliminated.

That is, for the above-described response delay, because the sensing amount is pressure, the response is transmitted at the speed of sound, the response does not change depending on the sensor position, and the response delay is related to the physical property value of the pressure sensor. Responsiveness of several tens msec or less can be secured. Regarding the response delay,
100 msec or less.

As described above, by using the pressure sensor, the pressure fluctuation state is sensed by the temperature sensor as in the related art, and the control is performed at a timing of several hundred msec, which is several times faster than the response delay 700 to 1200 msec required when the control operation is started. The operation can be started, the amount of overshoot and the amount of undershoot can be significantly reduced, and the user can always obtain stable mixed hot water at a constant temperature and can use the mixed hot water comfortably.

In addition, when the pressure fluctuates, as described above, the change in the pressure is sensed as early as one hundred and several tens msec or less, and the temperature control valve is moved at the maximum speed, and thereafter, or simultaneously, the PID control is performed by the signal of the temperature sensor. By adjusting the temperature by another control method, the reliability of the appropriate temperature control of the hot and cold water mixing apparatus can be further improved.

(F) Example Hereinafter, the present invention will be specifically described based on an example shown in the accompanying drawings.

FIG. 1 shows a conceptual overall configuration of a hot water mixing apparatus A according to the present invention. In the drawing, reference numerals 10 and 11 denote a hot water side flow path and a water side flow path, and both flow paths 10 and 11 have , Are provided with flow control valves 12 and 13, respectively. A valve driving device 14 such as a motor is interposed between the two flow paths 10 and 11, and the flow control valves 12, 13 are driven and opened and closed by the valve driving device 14, and are located on the upstream side. The mixed hot and cold water can flow through the mixed hot and cold flow path 15, and the temperature can be adjusted by changing the valve opening / closing degree to change the mixing ratio of the hot water and the water.

In the above configuration, the temperature control valve B is formed by the flow control valves 12, 13 and the valve drive device 14.

Further, the downstream side of the mixed hot / cold water flow path 15 is branched into a discharge fitting flow path 16 and a shower flow path 17, respectively. At the branch portion, switching valves 18 and 19 are provided. , 19 is
It is driven by a valve driving device 20 such as a motor, and can perform selection, flow rate adjustment, and water stoppage of a shower or discharge fitting of mixed hot water.

The switching valves 18 and 19 and the valve driving device 20 form a flow control / water stoppage / switching valve C.

Further, in FIG. 1, reference numerals 21 and 22 denote a temperature sensor and a flow rate sensor provided in the mixed hot water flow path 15, respectively, for detecting the temperature and / or the amount of the mixed hot water flowing in the mixed hot water flow path 15, Based on the detected output, the controller 23 generates an appropriate operation output to drive the temperature control valve B, whereby the temperature of the mixed hot and cold water can be controlled.

In FIG. 1, reference numeral 24 denotes an operation panel that communicates with the controller 23. On the operation panel 24, a start / stop button a, a temperature setting button b, a switching button c, and the like are provided. By operating the controller 23, the controller 23 and the temperature control valve B are made operable, and the valve driving device 20 is driven to select the flow path of the shower flow path 17 and the discharge fitting flow path 16. Can be.

In this embodiment, the temperature control valve B is further provided with a hot water side flow path 10 and a water side flow path 11, which are the primary side (upstream side) of the valve B, and a secondary side (downstream side) of the valve. Pressure change ΔP1, ΔP2 of the water pressure between the mixed hot water channel 15
Is driven by the detection output of the hot / water pressure sensors 25, 26 (hereinafter, referred to as pressure sensors 25, 26) for detecting the pressure.

That is, the pressure sensors 25 and 26 are attached to bypass circuits 27 and 28 provided with the flow control valves 12 and 13 between the upstream and downstream regions, respectively, and the differential pressure ΔP1 (=
P1−P3) and ΔP2 (= P2−P3) can be detected.

Here, P1: the primary pressure of the hot water flow path 10, P2: the primary pressure of the water flow path 11, and P3: the secondary pressure of the mixed hot water flow path.

Then, based on the detection outputs detected by the pressure sensors 25 and 26, the controller 23 is operated, and by the operation of the controller 23, the temperature control valve B is driven to change the mixing ratio of hot water and hot water. The temperature of the mixed hot and cold water can be adjusted to the set temperature.

The controller 2 based on the detection outputs of the pressure sensors 25 and 26
In the operation of (3), since the sensing amount is pressure, the response is transmitted at the speed of sound, the response does not change depending on the position of the sensor, and the response delay due to the physical properties of the pressure sensors 25 and 26 itself is several tens. Responsiveness of less than msec can be secured.

As described above, by using the pressure sensors 25 and 26, the pressure fluctuation state is sensed by the temperature sensor as in the related art, and the response delay 700 to 1 required when the control operation is started.
The control operation can be started at a time several hundreds of msec several times faster than 200 msec, and as shown in FIG. 2, the overshoot amount ΔTo can be significantly reduced as compared with the overshoot amount Δto in the conventional control method. Yes, the user always
A stable mixture of hot and cold water can be obtained, and the mixed hot and cold water can be used comfortably. This is the same for the undershoot amount.

In FIG. 2, Ts is a set temperature of the mixed hot and cold water.

In addition, in this embodiment, in addition to the pressure sensors 25 and 26, the temperature sensor 21 is also provided. Therefore, when the pressure fluctuates, as described above, the change in the pressure is sensed as early as one hundred and several tens msec or less. The temperature control valve B is moved at the maximum speed, and thereafter, that is, in a normal state, the temperature can be controlled by another control method such as PID control by the detection signal of the temperature sensor 21. The reliability of the appropriate temperature control can be further improved.

FIGS. 3 and 4 show a specific configuration of the hot and cold water mixing apparatus A according to the present embodiment.
The pressure sensors 25 and 26 form bypass circuits 27 and 28 on a part of the wall constituting the temperature control valve B,
The pressure sensors 25 and 26 are mounted in the middle of the lines 7 and 28.

Although various types of pressure sensors 25 and 26 can be used, in this embodiment, those shown in FIGS. 5 and 6 are used. That is, the pressure sensor 25 (the same applies to the pressure sensor 26) includes a pressurized conductive material 31 in a rubber 30.
Pressure difference ΔP1 (= P1−P3)
Then, by bending from the state shown in FIG. 5 to the curved state shown in FIG. 6, the resistance value of the pressurized conductive material 31 changes,
The change in the resistance is taken out by the lead wire 32 and the differential pressure is sensed.

FIG. 7 shows the resistance-differential pressure characteristics of the pressure sensors 25 and 26.

However, the pressure sensors 25 and 26 are not limited to those shown in the drawings, and for example, a semiconductor pressure sensor or a strain gauge may be used.

Further, in this embodiment, basically, in order to keep the mixing temperature, that is, the temperature T3 of the mixed hot and cold water, as shown in the following equation (a), the hot water supply temperature T1 and the hot water supply temperature T2 are constant. The hot water supply amount Q, regardless of the hot water supply / water supply pressures P1 and P2.
1, The water supply ratio of the water supply amount Q2 may be made constant. That is, Than Assuming that P1−P3 = ΔP1, P2−P3 = ΔP2, If the state before pressure fluctuation is i and the state after pressure fluctuation is o, , And In the above equations (a) to (f), α1: flow coefficient on the hot water supply side, α2: flow coefficient on the water supply side, A1: cross sectional area of the valve flow path on the hot water supply side, A2: cross sectional area of the valve flow path on the water supply side It is.

Therefore, if the settings of α1A1 and α2A2 are changed so as to satisfy the expression (f) with respect to the pressure fluctuations of ΔP1 and ΔP2, hot water of a constant temperature is automatically supplied.

In the present embodiment, the temperature control valve B includes the flow rate control valves 12 and 13 and the valve driving device 1 that drives them integrally.
However, the same operation and effect can be obtained even if the flow rate control valves each having the valve driving device are provided independently in the hot water side flow path 10 and the water side flow path 11.

Further, in the present embodiment, the pressure sensor is
Hot-side pressure sensor that detects the water pressure of the water and the water-side flow path 11 respectively
Although formed by 25 and the water-side pressure sensor 26, the water pressure of only one of the flow paths (for example, the water-side flow path 11 when there is little pressure fluctuation in the hot-water-side flow path 10) is detected. It is also possible to control the temperature of the mixed hot and cold water by changing the mixing ratio of the hot and cold water by driving the temperature control valve B via the controller 23 only by the detection output of the pressure sensor and by only the detection output of the pressure sensor. Good.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a conceptual configuration of a hot water mixing apparatus according to the present invention, FIG. 2 is a graph comparing a conventional hot water mixing apparatus with a hot water mixing apparatus according to the present invention, and FIG. FIG. 4 is a cross-sectional view taken along line II of FIG. 3, FIG. 5 and FIG. 6 are cross-sectional side views of a pressure sensor, and FIG. Pressure sensor resistance
FIG. 8 is a graph showing a differential pressure characteristic, FIG. 8 is a conceptual configuration explanatory view of a conventional hot water mixing apparatus, and FIG. 9 is a graph showing an appropriate temperature control performance of the conventional hot water mixing apparatus. In the figure, B: temperature control valve 10: hot water side flow path, 11: water side flow path 15: mixed hot water flow path, 23: controller 25: hot water side pressure sensor, 26: water side pressure sensor

Claims (2)

(57) [Claims] 1. A hot and cold water connection in which a hot water side flow path (10) and a water side flow path (11) are connected to a mixed hot and cold water flow path (15) via a temperature control valve (B) capable of changing a hot and cold water mixing ratio. In the mixing device, a pressure sensor that detects a water pressure of at least one of the hot water side flow path (10) and the water side flow path (11), and detects a temperature of the mixed hot water provided in the mixed hot water flow path. With the temperature sensor, the detection output of the pressure sensor and the temperature sensor,
A hot water mixing apparatus comprising: a controller (23) for controlling a temperature of the mixed hot water by driving a temperature control valve (B) to change a hot water mixing ratio of the mixed hot water. 2. A hot-water system in which a hot-water-side flow path (10) and a water-side flow path (11) are connected to a mixed hot-water flow path (15) via a temperature control valve (B) for varying a hot-water mixing ratio. In the mixing device, a pressure sensor that detects a pressure difference between the hot water side flow path (10) or the water side flow path (11) and the mixed hot water flow path (15), and a temperature control valve ( A hot water mixing apparatus comprising: a controller (23) for controlling the temperature of the mixed hot water by changing the hot water mixing ratio by driving B).