JPS63163731A - Hot water supply control system - Google Patents

Abstract

PURPOSE:To reduce the pressure loss in a water supply circuit and at the same time stabilize the temperature of the hot water by controlling the opening of a bypass control valve by the difference of signals from a discharged hot water temperature setting device and an incoming water temperature sensor. CONSTITUTION:Signals from a discharged hot water temperature setting device 31 and an incoming water temperature sensor 26 are read in a hot water supply control device 32 and calculation is conducted in a bypass arithmetic section in the hot water supply control device 32, and a drive device 20 is driven according to the difference of the set value of the discharged hot water and the temperature of the incoming water, and a mobile valve plate 15 is rotated by a specified angle. When the temperature difference is small, the mobile valve plate 15 rotates to make the bypass control valve 14 and a communication groove 16a communicable and the bypass flow flows. On the contrary the temperature difference is large, the bypass control valve 14 is shut with the communication grooves 16a and 16b so that the bypass flow does not flow. Namely when the difference of the set value between the discharged hot water temperature and the temperature of the incoming water is, the proportion of the bypass water flow is small and almost all of the total supply water passes through a heat exchanger 23 so that no boiling in the heate exchanger 23 occurs, and when the temperature difference is small, the proportion of the bypass water becomes larger and a large amount of water can be supplied, even if the pressure of the supply water is low, by bypassing the heat exchanger 23 which gives a large pressure loss.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to water flow control for instantaneous water heaters.

BACKGROUND OF THE INVENTION Conventional instantaneous hot water heaters are known to detect the temperature of hot water and control the amount of heating. There is also a bypass water circuit system that has a bypass path that bypasses a heat exchanger for the purpose of reducing water pressure loss, etc., and supplies hot water by mixing it with hot water heated by the heat exchanger. Bypass water circuit systems include a fixed bypass ratio type that maintains a constant ratio of bypass water volume to total water supply volume;
There is a bypass ratio changing type that increases the ratio of bypass water volume as the total water supply volume increases.

Disadvantages to be Solved by the Invention However, when a bypass water circuit system is used in the above-described hot water temperature control type water heater, there are the following problems. In other words, the fixed bypass ratio type has the drawback that if the bypass ratio is increased, boiling occurs in the heat exchanger when the set value of the outlet temperature is high, and if the bypass ratio is decreased, the effect of reducing pressure loss is lost. The above-mentioned disadvantages do not occur with the variable bypass ratio type, but since the bypass ratio also changes when the total amount of water supplied changes, the water temperature will fluctuate excessively in response to sudden changes in the total amount of water supplied, such as when the user suddenly opens and closes the faucet. There was a drawback to that.

The present invention has been made to solve the problems of the conventional method, and aims to reduce the pressure loss in the water supply circuit of a water heater and to stabilize the temperature of hot water.

Means for Solving the Problems In order to solve the above problems, the hot water supply control device of the present invention includes:
A heat exchanger, a heating device for this heat exchanger, a heating controller that controls the amount of heating of the heating device based on a signal from an outlet temperature setting device, an inlet water temperature detector, and a main control valve that controls the total amount of water supplied. a bypass control valve provided in a passage that bypasses the heat exchanger; a drive device for operating the main control valve and the bypass control valve; and the outlet water temperature setting device and the inlet water temperature detector. The opening degree of the bypass control valve is controlled based on the difference in signals.

According to the above configuration, the present invention increases the opening degree of the bypass control valve to obtain a large amount of water with low pressure loss when the difference between the outlet water temperature setting value and the inlet water temperature is large, and when the difference is small, the bypass control valve opens. This is to prevent ffl1llllfffr by reducing the opening degree of.

EXAMPLE A hot water supply control device which is an example of the present invention will be described below based on the accompanying drawings. In FIG. 1, reference numeral 1 denotes a valve body, in which water flows in through an inlet portion 2 and flows out through a main outlet portion 3a and a bypass outlet portion 3b. The inlet portion 2 enters the vortex chamber 4 having a circular cross section from the tangential direction, and the sphere 4 a rotates within the vortex chamber 4 due to the vortex flow generated within the vortex chamber 4 . 5 is a rotation detector consisting of a magnetic sensor or an optical sensor. A water amount detector 6 is constituted by the vortex chamber 4, the sphere 4&, and the rotation detection fa5. A support body 7 is integrally attached to the valve body 1 and has an inlet part 8, an outlet part 9, and a bypass part 10, and has elastic bodies 8a, 9a, and 10, respectively.
10a is provided. A fixed valve plate 11 is mounted on the support γ.
9 are integrally attached, and the fixed valve plate 11 has a main control valve 12, an outlet hole 13, and a bypass control valve 14 corresponding to the inlet section 8, outlet section 9, and bypass section 10 of the support body 7, respectively. There is a movable valve plate 15 on the fixed valve plate 11, and communication grooves 16 are provided at positions corresponding to the main control valve 12, the outlet hole 13, and the bypass control valve 14 of the fixed valve plate 11. As shown in FIGS. 2A and 2B, it consists of a first communication groove 16a that communicates with the bypass control valve 14 and a second communication groove 16b that closes the bypass control valve 14. The rotation of the movable valve plate 16 changes the fluid resistance at the main control valve 12. The movable valve plate 15 can be rotated by a rotating body 17, and the rotating body 17 is operated by a drive device 20 consisting of a motor 18 and a gear box 19.

21 and 22 are switches for detecting the position of the rotating body 18, respectively. Water flows in two directions through the communication hole 16, one flowing from the main outlet 3a to the heat exchanger 23, and the other flowing from the bypass outlet 3b to the bypass path 24, and flowing into the heat exchanger 2.
It merges with the tapping pipe 25 of No. 3 at the mixing part 25a. An inlet water temperature detector 26 is provided upstream of the valve body, and an outlet water temperature detector 27 is provided in the mixing section 25a. The inlet water temperature detector 26 detects the temperature before being heated by the heat exchanger 23,
The outlet hot water temperature detector 27 detects the temperature of the hot water heated by the heat exchanger 23 or the mixed temperature of the hot water from the heat exchanger 23 and the bypass passage 24 . Gas is supplied from the gas supply path 28 to the heating controller 29
The amount of gas is adjusted in the heating device 30, and the gas is combusted in the heating device 30 to heat the heat exchanger 23. 31 is a hot water temperature setting device composed of a variable resistor and the like. 32 is a hot water supply controller consisting of a microprocessor, which inputs signals from the water amount detector 7, inlet water temperature detector 26, outlet water temperature detector 27, and switches 21 and 22, performs arithmetic processing, and then outputs signals from the drive device 20.
, outputs a signal to the heating controller 29.

Next, the operation will be explained. In FIG. 1, when the power is turned on, the signals from the outlet water temperature setting device 31 and the inlet water temperature detector 26 are read, and the output temperature? The drive device 2o operates according to the difference between the 9J temperature setting value and the incoming water temperature, and rotates the rotating body 17 until the position is detected by the switch 21. Thereafter, when the user opens the faucet and starts water flow, the signal from the water amount detector 6 is read, fuel is supplied to the heating device 30, and combustion begins. The temperature of the mixed hot water of the hot water heated by the heat exchanger 23 and the water passing through the bypass path 24 is detected by the outlet temperature detector 27, and the heating controller 29 is driven by this signal and the signal of the outlet temperature setting device 31. , adjust the heating amount of the heating device 30. Further, the drive device 20 is finely adjusted by the signal from the water amount detector 6 to control the total water supply amount.

Next, the control operation will be explained in more detail with reference to FIGS. 2 and 3. When the power is turned on and the outlet temperature is set by the user, the outlet water temperature setting device 31 and the inlet water temperature detector 2 are activated.
6 is read into the hot water supply controller 32, and is calculated by the bypass calculation section 32a inside the hot water supply controller 32, and the drive device 20 is driven according to the difference between the hot water temperature setting value and the incoming water temperature, and the movable valve plate 15 is activated. Rotate by a predetermined angle. If the above temperature difference is small, move the valve plate 1 to the position shown in Figure 2A.
5 rotates, the bypass control valve 14 and the communication groove 16a communicate with each other, and a bypass flow flows. Conversely, when the temperature difference is large, the bypass control valve 14 and the communication grooves 16a, 16b are both blocked and the bypass flow does not flow, as shown in FIG. 2C. In other words, when there is a large difference between the outlet hot water temperature setting value and the incoming water temperature, the ratio of the bypass water amount is small and most of the total water supply amount passes through the heat exchanger 23, so it does not boil in the heat exchanger 23, and the temperature difference is small. In some cases, the ratio of the amount of bypass water becomes large, and by bypassing the heat exchanger 23, which has a high pressure loss, a large amount of water can be supplied even if the water supply pressure is low.

Further, the water amount setting calculation unit 32b of the hot water supply controller 32 calculates the signal difference between the hot water temperature setting device 31 and the incoming water temperature detector 26 and the heating capacity of the heating device 30, and calculates the heating capacity of the heating device 30.
Set the maximum amount of water that guarantees the hot water temperature set in step 1. After that, when the water flow is started, the water amount detector 6 detects the water supply amount, and when the water supply amount reaches the ignition start water amount or more, fuel is supplied to the heating device 30 and the ignition operation is performed to start the heating device 3.
0 combustion begins. When the water supply pressure is high and a large amount of water is supplied, the deviation between the signal from the water flow detector 6 and the signal from the water flow setting calculation section 32b is calculated by the water flow control calculation section 32a to drive the drive device 2o. The main control valve 12 controls the amount of water by rotating the movable valve plate 15. At this time, the opening degree of the bypass control valve 14 does not change. The heating amount of heating device 30 is adjusted by heating controller 29 . Heating controller 29
is controlled by the value of the heating load calculated by the hot water temperature control calculation section 32d based on the difference between the signal from the hot water outlet temperature setting device 31 and the signal from the incoming water temperature detector 26 and the signal from the water flow rate detector 6. It is corrected by the deviation signal between the device 31 and the hot water temperature detector 27, and finally the hot water temperature equal to the hot water temperature setting is obtained.

The timer 32e of the hot water supply controller 32 measures the time elapsed since the signal from the water amount detector 6 reached the above-mentioned ignition start water amount or less. In other words, it measures the time that has passed since hot water supply was stopped,
The opening degree of the bypass control valve 14 is corrected depending on the magnitude of the value. The opening degree of the bypass control valve 14 is set to be smaller than the normal setting value when resupplying hot water after a long period of time has passed after stopping the hot water supply, and the opening degree is set to be larger than the set value when resupplying hot water within a short time. When resupplying hot water after a long period of time has elapsed after the hot water supply was stopped, including during initial use, a bypass water amount is supplied smaller than the open setting value within a predetermined time, thereby reducing the delay in the rise of the hot water temperature due to the heat capacity of the cooled heat exchanger 23. Improve. Furthermore, when hot water is re-supplied within a short time after hot water supply is stopped, the amount of bypass water is supplied to be larger than the open setting value within a predetermined period of time, and an excessive rise in the outlet temperature caused by the heat capacity of the heated heat exchanger 23 is improved.

In the embodiment of the present invention, one bypass control valve 14 is shown, but it is also possible to provide a plurality of bypass control valves on the fixed valve plate 11 to perform multi-stage switching.

Effects of the Invention As described above, the hot water supply control device of the present invention has the following advantages:
A heating controller that controls the heating amount of the heating device, an inlet water temperature detector, a main control valve that controls the total water supply amount, a bypass control valve provided in a passage that bypasses the heat exchanger, and a main control valve. The opening degree of the bypass control valve is controlled by the difference in signals between the drive device that operates the bypass control valve, the outlet hot water temperature setting device, and the incoming water temperature detector, so that the following effects can be obtained.

(1) When the difference between the hot water temperature setting and the water inlet temperature is large, that is, the hot water temperature rises significantly, and the hot water temperature in the heat exchanger becomes high, most of the total water supply is passed through the heat exchanger, so there is no risk of boiling. In addition, bypass water flow control is performed immediately when the outlet water temperature is set or when the inlet water temperature changes, so there is no detection delay and higher safety than when boiling at the heat exchanger outlet is detected by temperature.

(2) When the difference between the hot water temperature setting and the incoming water temperature is small, i.e., when the hot water temperature rise is small and a large amount of hot water can be supplied, the amount of bypass water increases and the pressure loss in the heat exchanger does not increase, so the water supply pressure is low. A large amount of hot water can be dispensed.

(3) The amount of water supplied to the heat exchanger and bypass does not change due to sudden opening/closing of faucets or sudden fluctuations in water supply pressure, so excessive fluctuations in hot water temperature are small.

4) Since the main control valve and the bypass control valve can be operated by one drive device, it is small and inexpensive.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a hot water supply control device showing an embodiment of the present invention, Fig. 2 A, B, C, and D are a front view and a cross-sectional view respectively illustrating the water flow control operation of the same device, and Fig. 3 is a block diagram showing control signals of the device. 11...Fixed valve plate, 12...Main control valve, 14...11. Bypass control valve, 15...
Movable valve plate, 20... Drive device, 23...
・Heat exchanger, 26...Inlet water temperature detector, 29・
... Heating controller, 30 ... Heating device, 3
1... Hot water temperature setting device, 32... Hot water supply controller. Name of agent: Patent attorney Toshio Nakao and one other person
-Ichigo Yakura 2 Kan 2nd Figure A /3 16ku

Claims (3)

[Claims] (1) A heat exchanger, a heating device for the heat exchanger, a heating controller that controls the heating amount of the heating device based on a signal from an outlet temperature setting device, an inlet water temperature detector, and a total amount of water to be supplied. a main control valve, a bypass control valve provided in a passage that bypasses the heat exchanger, a drive device for operating the main control valve and the bypass control valve, the outlet hot water temperature setting device, and the inlet water temperature detector. A hot water supply control device that controls the opening degree of the bypass control valve based on a signal difference between the bypass control valve and the bypass control valve. (2) The main control valve and the bypass control valve consist of a fixed valve plate and a movable valve plate with communication holes corresponding to the inlet and outlet holes of the fixed valve plate or the bypass hole, and the movable valve plate is connected to the drive device. The hot water supply control device according to claim 1, which is operated by. (3) The hot water supply control device according to claim 1, which increases the bypass valve opening when the signal difference between the output hot water temperature setting value and the incoming water temperature detector is large, and decreases the bypass valve opening when the difference is small. .