JPS62123512A - Hot and cold water mixing valve device - Google Patents

Abstract

PURPOSE:To minimize both the overshoot and undershoot and also to prevent previously the hunting phenomenon by resetting the switching temperature to its original level in case the temperature difference between the tepid water detecting and setting means is kept within a fixed range for a fixed period of time. CONSTITUTION:A temperature difference monitor means 26 contains a timer which is started by the generation of the switch signal SW. Then the reset signal RS is produced and the output set value of a switching temperature setting/changing means 25 is reset to the initial values a1 and -a1 as long as the output temperature difference DELTAT of a comparator means 23 is kept within a reference temperature range for a fixed period of time after the timer is started. Therefore a memory control means 27 usually reads a low-speed characteristic curve out of a ROM 28. However this low-speed characteristic curve is changed to a high-speed characteristic curve when the difference T between the real temperature TA and the set temperature TO exceeds the 1st switching temperature a1. For this purpose, an address changing action is carried out. Then the switching temperature set value (a) is changed to the 2nd set value a2. The means 27 can produce a prescribed address by using the value a2 as the data.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention involves mixing hot water at a predetermined temperature with water via an interlocking valve, controlling the mixing ratio using a control means, and adjusting the temperature to a desired set temperature. The present invention relates to a hot water mixing valve device capable of supplying hot water to a boiler, and particularly relates to an improvement in the control means.

(Prior art) A hot water supply valve that controls the amount of hot water passing through at a predetermined temperature, and a water supply valve that operates in conjunction with the hot water supply valve to control the amount of water that passes through, is provided, and the hot water and water passing through each valve are mixed in a mixing water pipe. By controlling this mixing ratio, each JA unit is loaded and unloaded, which supplies hot water at a predetermined temperature determined by the setting means to the boiler.

In this case, the temperature of the hot water supplied from the hot water supply pipe or water supply pipe to the set temperature and the temperature of the hot water supplied to the cooker (hereinafter referred to as "
(actual temperature)) may fluctuate significantly, leading to overshoot or undershoot. In this case, the aforementioned valve opening/closing speed is usually increased in order to speed up the return to the set temperature. A similar situation occurs during a so-called cold start, when hot water is first started from the pot.

A conventional valve opening/closing speed control unit/) for executing this type of control is as shown in FIG. 7, for example. That is, the unit includes a hot water temperature detecting means (71) for detecting the actual temperature T in the mixing water pipe, a hot water temperature setting means (72) for setting a desired hot water temperature, and a hot water temperature detecting means (71) for detecting the actual temperature T in the mixing water pipe. Actual temperature T^ and set temperature To of hot water temperature setting means (72)
Comparison means (73) for calculating the difference ΔT between
3), a memory control means (74) for generating an address for reading from a memory (ROM) (75) in accordance with the output ΔT, and the aforementioned ROM (75). The ROM (75) has a characteristic curve (80
) is remembered. That is, the control means controls the set temperature T
The memory (75
), the valve opening/closing operation speed R is sequentially read out and controlled as shown in the characteristic curve (80) in FIG. In this case, when the temperature difference ΔT is larger than a certain value a, the valve operating speed R responds at the upper limit speed RM, and when the temperature difference ΔT becomes smaller than this value a, the valve operating speed R also gradually decreases.

(Problem to be Solved by the Invention) According to the control means having the characteristic curve (80) as shown in FIG. The response becomes sharper, and the upper limit speed R
If M is set high enough, the response will be quick when the temperature difference is less than a, but pressure fluctuations and initial cold starts will easily cause overshoot or undershoot below the set temperature. As a result, these fluctuations are not repeated and hunting is likely to occur.

In order to prevent this hunting, hunting detection means (76) is provided in the configuration shown in FIG.
It has been proposed to store two types of characteristic curves (90) and (91) as shown in the figure. This changes the characteristic curve of the ROM (75) to the curve (90) so as to reduce the rate of change of the valve actuation speed when hunting occurs.
In this example, the curve is switched from the curve (91) to the curve (91). However, this control is a response after hunting occurs and minimizes overshoot and undershoot.
Or, it did not prevent hunting.

Accordingly, the present invention seeks to obviate one or more of the drawbacks of the prior art, both in pressure fluctuations and initial cold starts.

It is an object of the present invention to provide a hot water mixing valve device that can minimize overshoot and undershoot or prevent hunting.

(Means and operations for solving the problem) To achieve this object, according to the present invention, at least two types of characteristic curves of the control means are provided, and when the temperature difference exceeds a specific switching temperature, one type of characteristic curve is provided. Control is performed so that the characteristic curve shifts from one characteristic curve to the other, but multiple switching temperatures are provided for this transition, and the temperature difference is specified as positive and negative reference temperatures, and when the temperature difference exceeds the positive reference temperature. Sometimes, the switching temperature on the negative side is changed, and when the negative reference temperature is exceeded, the switching temperature on the positive side is changed, and each time this is repeated, the switching temperature is changed, and as a result, the temperature difference is When the temperature remains within a certain range for a certain period of time, the switching temperature is returned to the initial state. With this configuration, it is possible to make the transition to the rapid characteristic sequentially difficult each time the transition is performed, suppress overshoot and undershoot due to pressure fluctuation, and return to the initial state after stabilization. This makes it possible to deal with overshoot and undershoot at the initial cold start.

For example, according to the hot water mixing valve device according to the embodiment of the present invention, the hot water supply valve (3) that controls the passage of hot water at a predetermined temperature (-) and the water supply valve (4) that controls the amount of water passing through are connected to one
A drive means driven by a vehicle or driven by two shafts in conjunction with each other, mixes a predetermined amount of hot water passing through the hot water supply valve (3) and a predetermined amount of water passing through the water supply/help (4). a mixing water pipe (5) that leads to a flow rate and a flow rate, a temperature detection means (8) and a j-ft detection means (7) for detecting the temperature and flow rate in this mixing water pipe (5), respectively;
The opening/closing speed of the hot water supply valve (3) and the water supply valve (4) is determined according to a certain characteristic curve based on the temperature difference ΔT between the temperature T^ detected by the temperature detection means (8) and the desired set temperature To. control means having a help opening/closing speed control unit, the valve opening/closing speed control unit of the control stage having at least two characteristic curves (A, B);
The hot water supply valve (3) and the water supply valve (
4) A plurality of switching temperatures (at, a2.a3.
-al, -a2. -a3), and the temperature difference ΔT is the switching temperature (al, a2, 3a, -al, -a2.-
Execute the transition when the temperature difference ΔT exceeds a3), specify positive and negative reference temperatures (b, -b), and switch to the negative side when the temperature difference ΔT exceeds the positive reference temperature (b). When the temperature is changed and the negative reference temperature (-b) is exceeded, the positive switching temperature is changed, and each time this process is repeated, the switching temperature (
al, a2. a3. -al, -a2. -a3) sequentially changed to (al+a2-+a3), (-al-+-a2 +-
a3), and when the temperature difference ΔT is within a predetermined range for a certain period of time, the switching temperature is controlled to return to the initial state switching temperature (al).

For example, according to the hot water mixing valve installation according to the embodiment of the present invention, the valve opening/closing speed control unit of the control means changes the switching temperature from the positive side to the lower one every time the switching temperature is changed. The negative side is controlled to change from high to low.

Furthermore, for example, according to the hot water mixing valve device according to the embodiment of the present invention, the one characteristic curve of the valve opening/closing speed control unit of the control means is a rapid curve, and the other characteristic curve is a slow curve. Let it be a velocity curve.

Furthermore, for example, according to the hot water mixing valve device according to the embodiment of the present invention, the switching temperature in the initial state of the control means is the lowest temperature among the plurality of switching temperatures.

(Embodiments of the Invention) The present invention will be described in detail below with reference to the accompanying drawings. It should be noted that in each figure, the numeral ``-'' indicates the same object.

FIG. 1 shows an overall configuration diagram of a hot water mixing valve device according to an embodiment of the present invention. In the figure, (1) is a water supply pipe for supplying hot water at a predetermined temperature, (2) is a water supply pipe for supplying water, and (3) is the amount of hot water supplied by hot water pipe (1). The hot water supply valve to be controlled, (4) is this hot water supply valve (
3) is a water supply valve that controls the amount of water that passes through the water supply pipe (2), and (5) is a water supply valve that controls the amount of water that passes through the water supply valve (3) and a predetermined amount of hot water that passes through the water supply valve (4). t
mixing water pipe (6) that mixes water with water and leads it to Karan (8);
(7) is the water pipe that provides hot water at the desired temperature (5)
(8) a flow rate sensor for measuring the flow rM of the mixed water flowing through the
(9) is a temperature sensor such as a thermostand that measures the temperature of the mixed water flowing through the mixing water pipe (5), and (9) is an operation setting that turns the device on and off and sets the temperature and amount of hot water desired to be supplied. Means, (10) is the operation setting - two valves (3), (4) based on the setting contents of L stage (9)
Arithmetic control means (11) forms an opening/closing operation command signal CC for opening/closing operation, and (11) includes a drive circuit and a drive motor that drive the valves (3) and (4) by the command signal CC of the arithmetic control means (10). It is a driving means.

That is, according to this embodiment, the calculation control means (
10) forms a command signal CC so that hot water of a set amount and temperature is obtained in the run (6), and drives the drive means (
11) to operate valves (3) and (4). Therefore, the calculation control means (10) includes a flow rate control unit,
The valve opening/closing speed control unit controls the opening/closing speed of the valve to control the hot water temperature. The present invention relates to the latter, and a valve opening/closing speed control unit according to an embodiment of the present invention is shown in FIG. In the figure, (21) includes the aforementioned temperature sensor (8) and the actual temperature TA
(22) hot water temperature detection means for forming an electrical signal corresponding to;
Of the aforementioned operation setting means (3), the hot water temperature setting means (23) generates an electric signal Tol corresponding to the desired hot water temperature;
) calculates the difference between the output signals T^ and To of the hot water temperature detection means (21) and the hot water temperature setting means (22), and generates an electric signal corresponding to the difference temperature Δc between the actual temperature T^ and the set temperature To. (24) is a switching command means that determines whether the temperature difference ΔT is larger or smaller than a constant value a and forms a switching signal SW for switching the contents of the memory (to be described later); (25)
) is a switching temperature setting means for setting the switching temperature a of the switching command means (24), and (2B) is a temperature for determining whether the temperature difference ΔT is maintained within the reference temperature range for a certain period of time (for example, 10 seconds). The difference monitoring means (27) is a memory control means (28) which determines the content to be read from the memory (ROM) (2B) based on the signals ΔT and SW and generates a predetermined address.
) is a memory that stores a rapid speed characteristic curve A and a slow speed characteristic curve B shown in FIG. 3 in order to drive the valves (3) and (4).

Among the above components, important ones will be explained in further detail. The switching command means (24) passes the temperature difference signal ΔT as is, but also monitors whether the temperature difference ΔT exceeds the switching temperature set value a, and if it is ΔTea, transmits the switching signal. Send SW. Before the switching signal SW is generated, data corresponding to the slow speed characteristic curve B with a small rate of change in FIG. 3 is read from the ROM (28), and corresponding control is executed. Also, after the switching signal SW is generated, the third
Switching is made to the rapidity characteristic curve A shown in the figure, which has a large rate of change, the corresponding data is read from the ROM (28), and the corresponding control is executed. 8 If T≦a, slow speed characteristic curve B
Control with.

By the way, such a switching temperature setting value a is given by a switching temperature setting changing means (25), and this switching temperature setting changing means (25) is configured to control three switching temperatures, for example, first, second) and third. Temperature set value (al, a2.

a3)(at(a2(a3)) is prepared on the positive side and the negative side. These set values (al, a2, a3) are set at each timing when the switching signal SW of the switching command means (24) is sent out, that is, Each time the positive side and negative side reference temperatures are exceeded, the set value a is changed to d1 → a2 → a3 on the positive side and -al → -a2 → on the negative side.
-a3.

Further, the temperature difference monitoring means (28) is equipped with a timer that is started upon generation of the switching signal SW, and the output temperature difference ΔT of the comparison means (23) is set for a certain period of time (for example, 10 seconds) from the time when the timer is started. If the temperature is maintained within the range, a reset signal R5 is generated to reset the switching temperature setting changing means (25), and the output setting value of the switching temperature setting changing means (25) is set to the initial value ((at, -al)). Return to

Therefore, the memory control means (27) normally controls the slow speed characteristic curve B to be read from the memory (28), but if the temperature difference Δc between the actual temperature T^ and the set temperature To is the first
When the switching temperature (al) is exceeded, this switching temperature (al
), the address is changed so as to shift to the rapidity characteristic curve A. Further, since the switching temperature set value a is subsequently changed to the second set value (a2) as described above, the memory control means (27) receives this set value (a2) as data and inputs the predetermined address. According to the invention, the transition from the slow speed characteristic curve B to the fast speed characteristic curve A is made possible by the switching temperature temperature difference (at, -al ), and are changed sequentially each time the positive and negative reference temperatures are exceeded.
It is not possible to migrate to multiple locations at the same time. Note that the range of -0.5≦ΔT≦+0.5 is a so-called dead area in which the actual temperature T^ is considered to be acceptable as being at the set temperature To, and the valve is not operated.

Next, the operation of this embodiment will be explained with reference to the flowchart of FIG. 4 and the actual temperature change characteristic diagram of FIG. 5. In the following explanation, numbers (40) to (49) correspond to the symbols of each block in the flowchart. Also (43-
The codes such as Y) and (43-N) are the judgment block (43
) represent positive and negative judgments, respectively.Furthermore, the switching temperatures (al, a2.a3) are each 3°C.
, 5.5°C, and 8°C at intervals of 2.5°C) 1 (in this embodiment, the temperature is set at 3°C, which is the same as the first switching temperature a1).

When the device starts normally (40), the switching temperature setting means (
25) (7) Set the setting a to the first switching temperature (al) (-3°
C) The main controller (not shown) such as the CPU sets the coefficients m and n of the switching temperature setting changing means (25) to 1 (41.42).

Here, if the actual temperature T^ starts to rise by 1° due to pressure fluctuation and the difference ΔT from the set temperature To exceeds a1 = 3°C, the switching command means (24) checks T^>To +al. (43), this judgment does not hold.
43-Y) The switching command means (24) sends out the switching signal SW and operates the memory control means (27) so that the memory (28) selects the rapidity characteristic curve A. At the same time, in order to exceed the reference temperature b=3°C, this switching signal SW is given to the switching temperature setting changing means (25), and the coefficient value is advanced by one to set n=2 (44), and the switching temperature setting value - Prepare a2. This makes the control toward the undershoot side slow and suppresses the occurrence of undershoot.

However, if undershoot occurs, the switching command means (24) has checked that T^<To-a2, so this judgment is established and the switching command means (24) sends out the switching signal SW. , actuating the memory control means (27) such that the memory (28) selects the rapidity characteristic curve A.

Also, since the reference temperature b=-3℃ is exceeded earlier than this, T
Since ^≦To -b is established, 45-Y) Give this switching signal SW to the switching temperature setting change means (25), advance the coefficient value by one, set m=2, and set the switching temperature setting value (a2).
) to prepare. This makes the control toward the overshoot side slow and suppresses the occurrence of overshoot. According to this example, a similar modification is made at the switching temperature (a3
) (m=3.n,=3).

By the way, when the overshoot or undershoot is controlled and the normal state is restored, the temperature difference ΔT falls within a certain range. This check is performed by the temperature difference monitoring means (26).
In other words, the temperature difference monitoring means (26)
It monitors b≦T≦To+b (47), and if this judgment is established (47-Y), it sets its own timer (48) and continues monitoring (4El).

As a result, if To-b≦T＾≦TO+b is maintained until the end of the timer setting time (for example, 10 seconds), then (49-Y
), the coefficient value of the switching temperature setting change means (25) is set to the initial value m
= l, n = 1, and the switching temperature is set to the first temperature (al).
By returning the switching temperature to the initial state after suppressing overshoot and undershoot due to pressure fluctuations, overshoot and undershoot at the initial 1υl cold start can be suppressed.

Note that the symbols A and B below the time axis t in FIG. 5 indicate different characteristic curves A and B for executing the control. Also,
In the figure, "0" indicates the starting point of the timer.

The present invention is not limited to the following embodiments and modifications, and various other embodiments and modifications are possible within the technical scope of the present invention, and equivalent components may be used. It will be clear to those skilled in the art that interchangeability is possible. For example, the number of switching temperature settings is not limited to three, but it is possible to set a larger number.Also, the timing at which the timer is activated to return to the initial state is determined when the actual temperature enters the allowable temperature range. It is possible to determine not only the point in time but also as appropriate. Furthermore, there are two characteristic curves A with different slopes.
, H, but as shown in FIG. 6, characteristic curves C and D that are parallel to each other may be used.

(Effects of the Invention) According to the present invention, as described above, the valve speed control unit of the control means is provided with at least two types of characteristic curves of slow speed and rapid speed, and the switching for transition from slow speed to rapid speed is provided. A plurality of temperatures are provided, and this switching temperature is changed each time the positive and negative side reference temperatures are exceeded, and as a result, when the temperature difference remains within a certain range for a certain period of time, the switching temperature is changed to the initial state switching temperature. By restoring the temperature, it is possible to obtain a hot water mixing valve device that can minimize pressure fluctuations during normal hot water supply as well as overshoot and undershoot caused by an initial cold start, and can also prevent hunting.

[Brief explanation of drawings]

Fig. 1 is an overall system diagram of an embodiment of the present invention, Fig. 2 is a system diagram of a valve opening/closing speed control unit which is a main part of an embodiment of the invention, and Fig. 3 is a configuration diagram of a memory of an embodiment of the invention. , FIG. 4 is a flow chart for explaining the operation of the embodiment of the present invention, FIG. 5 is a characteristic diagram for explaining the operation of the embodiment of the present invention, and FIG. 6 is a flowchart for explaining the operation of the embodiment of the present invention. The memory configuration diagrams of FIGS. 7 to 9 are explanatory diagrams of the conventional device. In the drawing, (3) is the hot water supply valve, (4) is the water supply valve, and (5) is the water supply valve.
) is the mixing water pipe, (6) is the ring, (7) is the flow rate detection means, (8) is the temperature detection means, (8) is the first stage of operation setting, (1
0) is an arithmetic control means.

Claims (4)

[Claims] (1) A hot water supply valve that controls the amount of hot water passing through at a predetermined temperature;
A driving means for driving a water supply valve that controls the amount of water passing through one shaft or two shafts in conjunction with each other;
A mixing water pipe that mixes a predetermined amount of hot water passing through the hot water supply valve and a predetermined amount of water that passes through the water supply valve and guides the mixture to the water supply valve; a temperature detection means that detects the temperature and flow rate of the hot water in the mixing water pipe; Control means having a flow rate detection means and a valve opening/closing speed control unit that determines the opening/closing speed of the hot water supply valve and the water supply valve according to a certain characteristic curve based on the temperature difference between the temperature detected by the temperature detection means and a desired set temperature. In the hot water mixing valve device, the valve opening/closing speed control unit of the control means has at least two characteristic curves, and the one characteristic curve that determines the opening/closing speed of the hot water supply valve and the water supply valve determines the opening/closing speed of the hot water supply valve and the water supply valve. A plurality of switching temperatures are set for transition to a characteristic curve, the transition is executed when the temperature difference exceeds the switching temperature, and reference temperatures at which the temperature difference is positive and negative are identified, and a positive reference temperature is set. When the negative reference temperature is exceeded, the negative side switching temperature is changed, and when the negative reference temperature is exceeded, the positive side switching temperature is changed, and each time this is repeated, the switching temperature is controlled to be sequentially changed, and the temperature is A hot water mixing valve device characterized in that the switching temperature is controlled to return to the initial state switching temperature when the difference remains within a predetermined range for a certain period of time. (2) In the device according to claim 1, the valve opening/closing speed control unit of the control means is arranged such that each time the switching temperature is changed, the positive side of the switching temperature is changed from lower to higher. A hot water mixing valve device characterized in that the side is controlled to change from a high side to a low side. (3) In the device according to claim 2, the one characteristic curve of the valve opening/closing speed control unit of the control means is a rapid speed curve, and the other characteristic curve is a slow speed curve. A drought mixing valve device characterized by: (4) In the device according to claim 3, the switching temperature in the initial state of the control means is such that among the plurality of switching temperatures, the positive side is the lowest temperature, and the negative side is the highest temperature. A hot water mixing valve device characterized by: