JPH073643B2 - Hot water mixing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention adjusts the opening of the hot water supply valve and the water supply valve based on the deviation between the hot water temperature and the target temperature to change the mixing ratio of hot water and water. The present invention relates to a hot and cold water mixing apparatus for feedback control of hot water temperature, and particularly to a hot and cold water mixing apparatus capable of supplying hot water at a desired temperature in a short time even when hot water supply is started in a state where the opening degree of the hot water supply valve side is extremely large. .

(Prior Art) As is well known, a hot water mixing device connects a hot water supply pipe provided with a hot water supply valve and a water supply pipe provided with a water supply valve to the mixed water pipe, and the hot water passed through the hot water supply valve in the mixed water pipe. And the water that has passed through the water supply valve are mixed and introduced to currants or the like.

Such a hot and cold water mixing apparatus is generally provided with a temperature sensor for detecting the hot water temperature in the mixed water pipe in the mixed water pipe, and in accordance with the deviation of the hot water temperature from the set target temperature based on the output signal of the temperature sensor. The hot water supply valve and the hot water supply valve are driven in association with each other to adjust the mixing ratio of the hot water and the hot water supply temperature feedback control.

In such feedback control, if the control gain that defines the relationship between the deviation and the speed for adjusting the valve opening (valve opening / closing speed) is set to a large value, hunting is likely to occur. For this reason, for example, two types of control gains are prepared, a relatively small control gain is selected when the deviation is large, and a relatively large control gain is selected when the deviation is small. There has been proposed a configuration in which the opening / closing speed is controlled so as not to change significantly to prevent a rapid change in the outlet heated water temperature and to prevent hunting of the outlet heated water temperature due to feedback control. The configuration in which the control gain is made different in accordance with such a deviation and thereby the valve opening / closing speed is made different is effective as feedback control in a state in which hot water is being continued.

(Problems to be Solved by the Invention) However, when hot water supply is started from the hot water discharge stopped state, the following problems occur. When the hot water supply is stopped, the hot water temperature in the mixed water pipe decreases due to natural heat dissipation, so the feedback control system controls to increase the opening degree on the hot water supply valve side. As a result, the opening degree of the hot water supply valve is normally in the fully open state. Then, when hot water supply is started with the hot water supply valve fully opened or with its opening increased, hot water from the hot water supply valve that is fully opened or widened after hot water remaining in the mixed water pipe flows out, Since a large amount is supplied, the hot water outlet temperature is significantly higher than the target temperature. Furthermore, if control is performed to select a lower control gain in the state where this deviation is large, it takes a long time for the outlet heated water temperature to approach the target temperature. That is, when hot water is discharged from the hot water supply stopped state (at the time of cold start), hot water having a temperature higher than a desired hot water temperature is supplied.

The present invention has been made to solve such a problem, and detects that hot water supply has started from a hot water supply stop state (cold start), in which case the control gain is high for a preset time. By keeping the valve open and closed faster, the opening of the hot water supply valve that is fully opened or has a large opening can be adjusted at a high speed to shorten the time for supplying hot water higher than the target temperature. It is an object of the present invention to provide a hot and cold water mixing device.

(Means for Solving the Problems) In order to solve the above problems, in the hot and cold water mixing apparatus according to the present invention, as shown in FIG. 1, the hot water temperature detecting means for detecting the hot water temperature in the hot water mixing pipe is provided in the hot water mixing pipe. In the hot and cold water mixing device that controls the mixing ratio of hot water and water by driving the valve connected to the mixed water pipe based on the deviation between the hot water temperature detected by the hot water temperature detection means and the set target temperature, the gain is A plurality of different deviations-storage means for storing valve opening / closing speed control characteristics, valve opening detection means for detecting valve opening, and valve opening detected by the valve opening detection means exceeds a predetermined value, Further, when the hot water temperature detected by the hot water temperature detecting means exceeds the target temperature (when it is detected that the cold start state is detected), the deviation of the gain larger than the gain currently selected from the storage means is detected. And a characteristic selection holding means for selecting the valve opening / closing speed control characteristic and selecting the deviation-valve opening / closing speed control characteristic after holding the selected deviation-valve opening / closing speed control characteristic for a preset time. A valve opening / closing speed determining means for determining the valve opening / closing speed based on the deviation according to the deviation-valve opening / closing speed control characteristic selected and held by the characteristic selecting / holding means, and a valve opening / closing speed determined by the valve opening / closing speed determining means. Drive means for driving the valve.

(Operation) The storage means stores a plurality of deviation-valve opening / closing speed control characteristics having different gains.

When the valve opening exceeds the predetermined value and the outlet heated water temperature exceeds the target temperature (when it is detected that the cold start state is detected), the characteristic selection holding means provides a gain larger than the currently selected gain. The deviation-valve opening / closing speed control characteristic is selected, the selected characteristic is held for a certain period of time set by a timer or the like, and then the original deviation-valve opening / closing speed control characteristic is restored.

The valve opening degree determining means determines the valve opening / closing speed based on the deviation-valve opening / closing speed control characteristic and the deviation selectively held by the characteristic selecting / holding means. The drive means adjusts the opening degree of the valve based on the determined valve opening / closing speed.

Therefore, when the valve opening exceeds the specified value and the hot water outlet temperature exceeds the target temperature (when it detects that the cold start condition is detected), the gain of the feedback control system is kept constant for a certain period from that point. Since it is set to a large value, the valve opening is adjusted at high speed. As a result, the opening of the hot water supply valve that is fully opened or has a large opening can be adjusted at a high speed for a certain period of time from the start of tapping, thus shortening the time for supplying hot water higher than the target temperature. be able to.

After a certain period of time has passed from the start of hot water discharge, that is, after the opening of the hot water supply valve that is fully opened or has a large opening with a large control gain is adjusted at high speed, the original deviation (small control gain) -valve opening / closing Since the speed is returned to the speed control characteristic, stable hot water temperature control in which hunting of the hot water temperature is unlikely to occur is performed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

2 to 5 show a hot and cold water mixing apparatus according to an embodiment of the present invention, FIG. 2 is an overall schematic view, FIG. 3 is a flow chart, FIG. 4 is a timing chart, and FIG. 5 is a data table. is there.

In FIG. 2, (11) is a hot water supply pipe to which relatively high temperature hot water is supplied, (12) is a water supply pipe to which relatively low temperature water is supplied,
(13) is a hot water supply valve for adjusting the flow rate of hot water in the hot water supply pipe (11), and (14) is a water supply pipe (12) linked with the hot water supply valve (13).
A water supply valve that adjusts the flow rate of water in the inside, (15) is a mixing water pipe that mixes the hot water that has passed through the hot water supply valve (13) and the water that has passed through the water supply valve (14) to lead to the karan (16), (17) A potentiometer (valve opening detection means) for detecting the valve opening of the hot water supply valve (13), and (18) a temperature sensor (hot water temperature) for detecting the temperature (actual hot water temperature) of the mixed water in the mixed water pipe (15). (Detection means), (19) is an operating device for setting a target temperature (ts) and instructing driving / stopping of the device, and (20) is an operating device composed of a one-chip microcomputer having a CPU and a ROM ( 1
Controller that performs control based on the output signals of the potentiometer (17) and temperature sensor (18), etc.
1) is a driver which has a drive circuit, a motor, etc., and drives valves (13) and (14) based on the output signal of a controller (20). In the ROM of the one-chip microcomputer of the controller (20), the actual hot water (t) and the target hot water temperature (ts) are stored in the ROM as shown in FIG.
Two types of control characteristics (A) and (B) capable of specifying the opening / closing speed (R) of the valve in accordance with the deviation (Δt) from and are stored. Needless to say, RO has three or more control characteristics.
It is also possible to store in M. This controller (20)
Corresponds to the storage means (g), the characteristic selection holding means (i) and the valve opening / closing speed determining means (j), and the driver (21) corresponds to the driving means (k).

This hot and cold water mixing apparatus executes a series of processes shown in the flowchart of FIG.

First, the initialization control characteristics of the small gain (B) is in Sutevvu (P ₁₎ Next, the valve opening degree of the step in (P _2), hot water supply valve (13) based on the output signal of the potentiometer (17) (Θ) is the maximum opening (θmax) In other words, it is determined whether the hot water supply valve (13) is fully opened. If the hot water supply valve (13) is fully opened, the process of step (P ₃ ) is performed, hot water supply valve (13) performs the process of step (P ₅₎ if not fully open. Needless to say, the valve opening degree (θ) of the hot water supply valve (13) can be detected by the rotation angle of the output shaft of the motor of the driver (21). In step (P ₃ ), it is determined whether or not the tap water temperature (t) is higher than the target temperature (ts) based on the output signal of the temperature sensor (18), and the tap water temperature (t) is equal to the target temperature (ts). If it exceeds the limit, the step (P ₄ ) is processed, and the hot water temperature (t)
If is less than or equal to the target temperature (ts), the process of step (P ₅ ) is performed. In step (P _4), a large deviation of the gain - while selecting the valve opening and closing speed control characteristic (A), it starts timing by resetting the timer of the characteristic retention time (T _A) for counting. That is, in this step (P ₄ ), the control characteristic (A) with a large gain is selected when the hot water supply valve (13) is fully opened and the tapping temperature (t) is higher than the target temperature (ts) at the cold start. Then, as will be described later, this characteristic (A) is held for the time (T _A ) set in the timer. Therefore, according to this control characteristic (A), the deviation (Δ
The valve opening / closing speed (R) retrieved based on t) is also large, and the valves (13) and (14) are driven at high speed by the driver (21). As shown in FIG. Even if there is, the tap water temperature (t) can be quickly converged to the target temperature (ts).

In step (P ₅ ), it is judged whether or not the large gain deviation-valve opening / closing speed control characteristic (A) is selected, and if the control characteristic (A) is selected, control at cold start or the like is performed. If it is determined that it is in the middle, the process of step (P ₆ ) is performed. If the control characteristic (A) is not selected, it is determined that it is not a cold start and the process returns to step (P ₂ ). Therefore, if the hot water supply valve (13) is not fully opened, the valve opening / closing speed (R) of each valve (13) (14) is searched for based on the deviation (Δt) according to the control characteristic (B) and becomes small, and the hot water temperature ( The change in t) becomes small and the usability is not impaired. In step (P ₆ ), it is determined whether or not the timer, which has started time counting in the process of step (P ₄ ), completes counting of a predetermined time (T _A ), in other words, the characteristic (A) is the predetermined time ( T _A ) Judge whether or not it was retained.
Then, when the time measurement for the predetermined time (T _A ) is completed, a small gain deviation-valve opening / closing speed control characteristic (B) is selected in step (P ₇ ), and the predetermined time (T _A ) If the time measurement is not completed, the series of processes is repeated again. Therefore, as shown in FIG. 4, a large gain control characteristic (A)
Is held only for the predetermined time (T _A ) and the occurrence of so-called hunting in which the outlet heated water temperature (t) fluctuates with respect to the target temperature (ts) can be prevented.

(Effects of the Invention) As described above, in the hot and cold water mixing apparatus according to the present invention, when the valve opening exceeds the predetermined value and the hot water discharge temperature exceeds the target temperature (when it is detected that it is in the cold start state). In addition, after selecting the deviation-valve opening / closing speed control characteristic with a gain larger than the currently selected gain and holding the selected characteristic for a certain time set by a timer, etc., the original deviation-valve opening / closing speed Since the configuration is restored to the control characteristics, the temperature of the hot water in the mixed water pipe decreases, and in response to this, hot water supply is started with the hot water valve fully opened or the opening is large, and the hot water opening is large. Therefore, the opening of the valve is adjusted at a high speed for a certain period from the time when it is detected that hot water at the target temperature is starting to be supplied, so it is the time when hot water at a temperature higher than the target temperature is discharged. Can be shortened . Further, since the original gain deviation-valve opening / closing speed control characteristic is restored after a lapse of a certain time, stable hot water temperature control is achieved in which hunting of the hot water outlet temperature is unlikely to occur.

[Brief description of drawings]

FIG. 1 is a block diagram of a hot and cold water mixing apparatus according to the present invention. 2 to 5 show a hot and cold water mixing apparatus according to an embodiment of the present invention, FIG. 2 is a schematic overall view, FIG. 3 is a flowchart, FIG. 4 is a timing chart, and FIG. 5 is a deviation-valve. It is a data table showing opening / closing speed control characteristics. 11 …… Hot water supply pipe (b), 12 …… Water supply pipe (d) 13 …… Hot water supply valve (a), 14 …… Water supply valve (c) 15 …… Mixed water pipe (e) 17 …… Potentiometer (valve open Degree detecting means (h)) 18 ... Temperature sensor (hot water temperature detecting means (f)) 19 ... Manipulator 20 ... Controller (memory means (g), characteristic selection holding means (i), valve opening / closing speed determination) Means (j)) 21 ... Driver (driving means (k))

Front page continuation (72) Keiji Hayashi, Inventor Keiji Hayashi, 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu City, Fukuoka Prefecture (56) References JP-A-60-3705 (JP, A) 52-129061 (JP, U)

Claims (1)

[Claims] 1. A mixed water pipe is provided with hot water temperature detecting means for detecting a hot water temperature in the mixed water pipe, and the mixing is performed based on a deviation between a hot water temperature detected by the hot water temperature detecting means and a set target temperature. In a hot and cold water mixing apparatus for controlling a mixing ratio of hot water and water by driving a valve connected to a water pipe, a storage unit storing a plurality of deviation-valve opening / closing speed control characteristics having different gains, and a valve opening degree of the hot water supply valve And a valve opening degree detection means for detecting the valve opening degree, the valve opening degree detected by the valve opening degree detection means exceeds a predetermined value, and the outlet hot water temperature detected by the hot water temperature detection means exceeds the target temperature, The deviation-valve opening / closing speed control characteristic having a gain larger than the gain currently selected from the storage means is selected, and the deviation-valve opening / closing speed control characteristic is held for a preset period of time. Characteristic selection holding means for selecting the obtained deviation-valve opening / closing speed characteristic, and valve opening / closing speed determination for searching the valve opening / closing speed based on the deviation according to the deviation-valve opening / closing speed control characteristic selected and held by the characteristic selection holding means A hot and cold water mixing apparatus comprising: a means and a driving means that drives the hot water supply valve and the water supply valve in conjunction with each other at the valve opening and closing speed retrieved by the valve opening and closing speed determining means.