JPH0464835A - Hot water and cold water mixing device - Google Patents

Abstract

PURPOSE:To get a stable controlling performance even in a region where a less amount of flow rate of mixed hot water is found by a method wherein a controlling means converts an opening or closing speed in response to an actual flow rate detected by a flow rate sensing means when an opening or a closing of a hot water volume valve and a cold water volume are controlled. CONSTITUTION:A target temperature is set by a hot water temperature setting device 10 and a target flow rate is set by a flow rate setting device 11. At this time, the hot water volume valve 3 and the cold water volume valve 4 are initialized to their predetermined degrees of opening or closing. After setting the hot water temperature and flow rate, an operating valve 13 close at hand disposed in a shower 6 is opened. Then, a fed-out hot water sensor 14 disposed in a hot water feeder within a hot water mixing device C detects a starting of hot water feeding and gives the hot water feeding start signal to the controller 9. The controller 9 starts a sampling of an actual temperature of mixed hot water with a hot water temperature sensor 7 and an actual flow rate of the mixed hot water with a flow rate sensor 8, and starts a controlling of opening or closing of the hot water volume valve 3 and the cold water volume valve 4 in response to an operating amount calculated by a fuzzy estimation. An operating amount (f) is determined by a first fuzzy controller 20. An operating amount is determined by a second fuzzy controller 21 in response to a difference Q-q of a set flow rate Q and a detected flow rare (q).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a hot water mixing device that is used in hot water supply equipment such as a bathroom, and that mixes hot water to obtain mixed hot water at a predetermined temperature, or This invention relates to a hot water mixing device for obtaining mixed hot water at a predetermined flow rate.

[Conventional technology]

In controlling the hot water amount valve and the water amount valve in the hot water mixing device as described above, the target temperature is mixed based on the target temperature set by the hot water temperature setting means and the actual temperature of the mixed hot water detected by the hot water temperature detecting means. The amount of operation of both valves, that is, the opening/closing speed (including the opening/closing direction) is determined so that hot water can be obtained.

Furthermore, in order to obtain the target flow rate set by the flow rate setting means, the operation amounts of both valves are corrected with the auxiliary operation amount determined based on the target flow rate and the actual flow rate of the mixed hot water detected by the flow rate detection means. .

[Problem to be solved by the invention]

However, in a region where the flow rate of mixed hot water from the hot water mixing device is small, the hot water flow valve and the water flow valve are controlled to open and close in a range close to fully closed. In this case, there is a drawback that the linearity between each valve and the flow rate is lost, and control tends to become unstable, so there is room for improvement.

In view of the above, an object of the present invention is to provide a hot water mixing device that can provide stable control performance even in a region where the flow rate of mixed hot water is small.

[Means to solve the problem]

A first hot water mixing device according to the present invention (claim 1) includes a hot water temperature setting means for setting a target temperature of mixed hot water, a hot water flow valve for adjusting the inflow amount of hot water, and a water flow valve for adjusting the inflow amount of water. a hot water temperature detection means for detecting the actual temperature of the mixed hot water; and a hot water temperature detection means for opening and closing the hot water flow valve and the water flow valve at an opening/closing speed determined based on the target temperature and the actual temperature in order to obtain mixed hot water at the target temperature. The device is equipped with a control means for controlling, and its characteristic configuration is that a flow rate detection means for detecting the actual flow rate of the mixed hot water is provided, and the control means is configured to control the temperature when the target temperature and the actual temperature are the same. The opening/closing speed is configured to be lowered as the actual flow rate decreases.

A second hot water mixing device according to the present invention (claim 2) includes a hot water temperature setting means for setting a target temperature of mixed hot water, a flow rate setting means for setting a target flow rate of mixed hot water, and a water flow rate setting means for adjusting the inflow amount of hot water. a water flow valve, a water flow valve that adjusts the amount of water flowing in, a water temperature detection means that detects the actual temperature of the mixed hot water, a flow rate detection means that detects the actual flow rate of the mixed hot water; control means for controlling the opening and closing of the hot water flow valve and the water flow valve at an opening/closing speed determined based on the target temperature, the actual temperature, and a deviation between the target flow rate and the actual flow rate in order to obtain mixed hot water at a target flow rate; The characteristic configuration thereof is that the control means is configured to lower the opening/closing speed when the target temperature, the actual temperature, and the deviation are each the same as the actual flow rate decreases. It is in.

[For production]

According to the characteristic configuration of the first hot water mixing device, the control means:
When controlling the opening and closing of hot water and water volume valves, the opening and closing speed is
The flow rate is changed according to the actual flow rate detected by the flow rate detection means. In other words, even if the target temperature and the actual temperature are the same,
The lower the actual flow rate, the lower the opening/closing speed.

In the case of the second hot water mixing device, similarly to the first hot water mixing device, the control means changes the opening and closing speeds of both valves according to the actual flow rate. That is, even if the target temperature, the actual temperature, and the deviation between the target flow rate and the actual flow rate are the same, the lower the actual flow rate itself, the lower the opening/closing speed.

〔Effect of the invention〕

According to the present invention, regardless of whether the hot water mixing device is a first hot water mixing device that only adjusts the temperature of mixed hot water or a second hot water mixing device that adjusts the temperature and flow rate of mixed hot water, the characteristic configuration described above enables Stable control performance can now be obtained even in areas where the flow rate of mixed hot water is small.

〔Example〕

An embodiment in which the hot water mixing device according to the present invention is applied to a bath shower will be described below. FIG. 1 shows the system diagram. High-temperature hot water produced by a water heater is supplied to the hot water mixing device (C) from an inlet channel (1), and low-temperature water is supplied from an inlet channel (2). The flow of the supplied hot water and water is restricted by the hot water flow valve (3) and the water flow valve (4), respectively, and then mixed to form mixed hot water, which is then sent from the shower (6) connected to the tip of the hot water supply path (5). The bath is served.

The hot water mixing device (C) of this embodiment is of a type that can adjust the temperature and flow rate of mixed hot water, and the hot water supply path inside thereof is provided with a hot water temperature sensor (7) and a flow rate sensor (8).
The temperature and flow rate of each mixed hot water are detected and the detected information is provided to the control device (9). The control device (9) includes a hot water temperature setting device (10), a flow rate setting device (11), and an operation switch (1
2) etc. is connected to the operation panel (P).

The operation and control procedure will be explained using the flowchart shown in FIG. 2. First, turn on the operation switch (12) on the operation panel (P), set the target temperature (hereinafter referred to as set water temperature) using the hot water temperature setting device (10), and set the target flow rate (hereinafter referred to as set water temperature) using the flow rate setting device (II).
(hereinafter referred to as set flow rate). At this time, check the water flow valve (3
) and the water flow valve (4) are initialized to a predetermined opening/closing degree.

After setting the water temperature and flow rate as described above, open the hand-operated valve (13) provided in the shower (6). Then, the hot water detector (1) installed in the hot water supply path inside the hot water mixing device (C)
4) detects the start of hot water dispensing and transmits the hot water dispensing start signal to the control device (9).
). The control device (9) detects the actual temperature of the mixed hot water (hereinafter referred to as detected hot water temperature) by the hot water temperature sensor (7) and the flow rate sensor (
8) starts sampling the actual flow rate of the mixed hot water (hereinafter referred to as detected flow rate), and starts opening/closing control of the hot water flow valve (3) and water flow valve (4) based on the operation amount obtained by fuzzy reasoning as described later. .

When the hand operated valve (13) is closed to stop the hot water supply, the control device (9) stops the above control in response to the hot water supply stop signal from the hot water supply detector (14).

Next, the hot water flow valve (3) and the water flow valve (4) based on fuzzy reasoning are explained.
) opening/closing control will be explained. As shown in the fourth control block diagram, the control device (9) controls the deviation (Tt) between the set hot water temperature (T) and the detected hot water temperature (1) and the amount of change Δ(T-
t) and from them the first fuzzy controller (20)
Determine the manipulated variable f. Further, the manipulated variable k is determined by the second fuzzy controller (21) from the deviation (Q-q) between the set flow rate (Q) and the detected flow rate (q). Here, the fuzzy controller means a combination of a plurality of control rules and a fuzzy inference section.

The manipulated variables f and k correspond to the number of pulses per second given to the motor that drives the water flow valve (3) and the water flow valve (4), and are therefore proportional to the opening/closing speed of both valves (3) and (4). and,
A positive value for both f and k means the direction in which the valve opens, and a negative value means the direction in which the valve closes.
) is a manipulated variable that controls opening and closing in opposite directions, and k is a manipulated variable that controls opening and closing of both valves (3) and (4) in the same direction. That is, the operation amount of the hot water flow valve (3) is F1=(-f+k)
, the operation amount of the water flow valve (4) is F2=(f+k). The manipulated variables F1 and F2 are corrected according to the detected flow rate q as described later, and the final hot water flow valve (3) and water flow valve (
4) is the manipulated variable.

Next, the first fuzzy controller (20) and the second fuzzy controller (21) will be explained. First, as mentioned above, the first fuzzy controller (20)
-t) and the amount of change thereof, ΔA, to determine the manipulated variable f. The control rule is a fuzzy variable A1Δ with two antecedents.
A, and their membership functions are shown in FIGS. 5 and 6, respectively. Further, the manipulated variable f that describes the consequent part of the control rule is assumed to be a set of discrete singletons as shown in the membership function in FIG.

The control rules described by these fuzzy variables are
For example, 11 A=pb & ΔA=pb THENf
=nb, but in this example, variable A can take 7
A control rule is defined for determining the manipulated variable f for 35 combinations of the value of ΔA and the five possible values of the variable ΔA.

If the value of the variable A is taken in the vertical direction and the value of the variable ΔA is taken in the horizontal direction, and the relationship with the manipulated variable f is expressed in a matrix table, the result will be as shown in Table 1.

Table 1 △A The first fuzzy controller (20) stores control rules in the table format shown in Table 1, and the temperature deviation A and its variation Δ
Based on the input of A, the manipulated variable f based on the control rule is determined by table lookup. In this case, the degree of conformance of each control rule to the input quantities A and △ is determined by the membership function (
The smaller of the degrees of conformity (grade) to the control rules (FIGS. 5 and 6) is defined as the degree of conformity to the control rule. The resulting manipulated variable f is weighted by the degree of suitability. Then, the weighted average of the manipulated variables f obtained from each control rule is set as the manipulated variable f determined by the first fuzzy controller (20).

This will be explained below using specific numerical values. If A=6
If ΔA = 1.5 C], then from FIG. 5, A matches both pm and ps with a grade of 0.3. Further, from FIG. 6, ΔA matches both pb and ps with a grade of 0.5. Therefore, the four types of control rules surrounded by double lines in Table 1 will be applied, and when calculating the manipulated variable f for each, from the top left for the four types of control rules surrounded by double lines, Clockwise, 0.3nb, 0.3
n b, 0.3 nm, 0.3 nm. If we substitute specific numerical values for each position of the manipulated variable f from Figure 7 and take the weighted average, we get f = (0,3X(-50)+〇,3X(-50)
+0.3X(-15)+0.3x(-15))/(0,
3+0.3+0.3+0.3)=-32,5[pps
] becomes. This is the operation amount determined by the first fuzzy control unit (20) from the hot water temperature deviation A=6 ('C) and its variation ΔA=1.5C°C].

As described above, the second fuzzy controller (21) determines the manipulated variable k from the flow rate deviation B=(Q-q).

The antecedent part of the control rule is described by only one fuzzy variable B, and the membership function of variable B is shown in FIG. The first fuzzy controller (
20), the membership function is represented by a discrete singleton, which is shown in FIG. The control rules are expressed as, for example, TF B=pb THEN k=pb, and the relationship between B and k for the five control rules is shown in Table 2.

Below in Table 2, the process of fuzzy inference will be explained using specific numerical values, similar to the explanation of the first fuzzy controller (20). If B=10[]/m1nl, then from FIG. 8, B matches pb with a grade of 0.3 and matches ps with a grade of 0.7. Therefore, two control rules in Table 2 are applied, and the manipulated variables =0.3 pb and =0.7 ps are determined for each. Substituting specific numerical values for each position of the manipulated variable f from Fig. 9 and taking the weighted average, k = (0,3X15+0.7X5)/(0,3+0
．． 7)=8 [ppsl. This is the manipulated variable determined by the second fuzzy controller (21) from the flow rate deviation B=10[1/mlnl.

From the manipulated variable f = −32,5 [ppsl determined by the first fuzzy controller (20) in this way and the manipulated variable k = 8 [ppsl] determined by the second fuzzy controller (21), the following equation is obtained in FIG. As shown in , the operation amount F 1 of the hot water flow valve (3)
= -f + k = 40.5 [11 pS] and the operation amount of the water flow valve (4) F 2 = f + k = -24,5 [ppsl] are determined.

Apart from the correction described later, the control device (9) controls the hot water flow valve (
3) in the opening direction at a speed proportional to the manipulated variable [40, 5], and the water flow valve (4) is controlled in the closing direction at a speed proportional to the manipulated variable [-24, 5].

As a result, the water temperature deviation A=(T-t) becomes smaller, and the flow rate deviation B=(Q-q) is adjusted to become smaller.

Next, the correction of Fl and F2 shown in the subroutine in the flowchart of FIG. 2 will be explained. A flow chart of this part of the process is shown in FIG.

In the first half (a) of the process, when the detected flow rate q of the mixed hot water is small, Fl and F2 are corrected to be small. If the flow rate is small, the water flow valve (3) and water flow valve (4) will be controlled to open and close in a state that is almost fully closed, and the linearity between the degree of opening and closing and the flow rate will be lost, and the control will likely become unstable. Therefore, this correction is made to improve stability by lowering the opening and closing speeds of both valves (3) and (4). In this embodiment, Fl and F2 are lowered in two stages depending on the detected flow rate q. That is, when q is less than 20 (1/m), Fl and F2 are multiplied by 1/4, and when q is more than 20 (1/m) and less than 30 (1/m), Fl and F2 are multiplied by 1/4. An operation to multiply by 2 is performed.

In the processing of the second half (b) of FIG. 3, Fl.

If both of the results obtained for F2 are zero, they are replaced with the positive minimum manipulated variable (+, [I]I]S]). This is the control amount obtained when both the hot water temperature deviation A and the flow rate deviation B are zero, that is, both valves (3).

Even if the opening/closing speed of (4) is zero, both valves (3) actually
, (4) Since it is not preferable for stable control to stop the opening/closing operations, at least one of the valves is kept in a state of operation at all times.

With the above two corrections, the hot water mixing device of this embodiment is
Mixed hot water with more stable hot water temperature and flow rate can be obtained.

[Another example]

In the example, whether only the detected flow rate q was used as an input condition when correcting the manipulated variable according to the flow rate of the mixed hot water;
As shown in the flowchart of FIG. 10, better control can be achieved by adding the set flow rate Q to the input conditions. That is, by setting both as an AND condition, even if the detected flow rate q is small, when the set flow rate Q is sufficiently large, the above-mentioned Fl is applied.

F2 correction calculation is not performed. This is because in such a transient control state, priority should be given to quickly approaching the set hot water temperature and set flow rate rather than stabilizing the detected hot water temperature and detected flow rate.

In addition, although the embodiment is a hot water mixing device of a type that adjusts both the temperature and flow rate of mixed hot water, a hot water mixing device of a type that only controls the temperature of mixed hot water, that is, a hot water mixing device that is not equipped with a flow rate setting means, can also be used for mixing hot water and hot water. By providing hot water flow rate detection means and correcting the amount of operation of the hot water flow valve and the water flow valve in the same manner as in the embodiment, mixed hot water with a more stable temperature can be obtained. Alternatively, instead of providing the mixed water flow rate detection means, a means for detecting the degree of opening and closing of both valves may be provided, and the above-mentioned operation amount correction may be performed in a region where both valves are close to being fully closed.

In addition, in the embodiment, the operating amounts of the hot water flow valve and the water flow valve are determined by fuzzy reasoning from three manual inputs: the hot water temperature deviation, the amount of change thereof, and the flow rate deviation, and then the operating amounts are corrected according to the flow rate. Although the configuration is such that the operation amount, that is, the opening/closing speed is lowered as the flow rate decreases, the present invention is not limited to this. For example, by adding the flow rate to the input of the fuzzy inference section in advance and adding new control regulations accordingly, Control may be implemented to reduce the opening/closing speed as the flow rate decreases.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

1 to 9 are diagrams relating to a hot water 5L combining device according to an embodiment of the present invention, in which FIG. 1 is an example of its application, FIG. 2 is a flowchart of control, and FIG. 3 is a flowchart of correction control. FIG. 4 is a control block diagram, and FIGS. 5 to 9 show membership functions of fuzzy variables. FIG. 10 is a flowchart of correction control according to another embodiment. (3)...Hot water flow valve, (4)...Water flow valve, (7)...Hot water temperature detection means, (8)...
・Flow rate detection means, (9)... Control means, (10
)...Hot water temperature setting means, (11)...Flow rate setting means.

Claims (1)

[Claims] 1. Hot water temperature setting means (10) for setting the target temperature of mixed hot water
, a hot water flow valve (3) for adjusting the inflow amount of hot water, a water flow valve (4) for adjusting the inflow amount of water, a hot water temperature detection means (7) for detecting the actual temperature of the mixed hot water, and a hot water temperature detection means (7) for detecting the actual temperature of the mixed hot water; A hot water mixing device comprising a control means (9) for controlling opening/closing of the hot water volume valve (3) and the water volume valve (4) at an opening/closing speed determined based on the target temperature and the actual temperature in order to obtain hot water at a mixed temperature. A flow rate detection means (8) for detecting the actual flow rate of the mixed hot water is provided, and the control means (9) controls the opening/closing speed in the case where the target temperature and the actual temperature are the same. A hot water mixing device configured to lower the flow rate as it decreases. 2. Hot water temperature setting means (10) for setting the target temperature of mixed hot water
and a flow rate setting means (11) for setting the target flow rate of the mixed hot water.
, a hot water flow valve (3) for adjusting the inflow amount of hot water, a water flow valve (4) for adjusting the inflow amount of water, a hot water temperature detection means (7) for detecting the actual temperature of the mixed hot water, and a hot water temperature detection means (7) for detecting the actual temperature of the mixed hot water. a flow rate detection means (8) for detecting the actual flow rate of hot water; and a flow rate detection means (8) for detecting the target temperature, the actual temperature, and
and a hot water mixing device comprising a control means (9) for controlling opening and closing of the hot water flow valve (3) and the water flow valve (4) at an opening/closing speed determined based on a deviation between the target flow rate and the actual flow rate, The control means (9) is a hot water mixing device configured to lower the opening/closing speed when the target temperature, the actual temperature, and the deviation are the same as the actual flow rate decreases.