JPH0689903B2 - Water heater - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply device that realizes instantaneous hot water supply and freeze prevention by keeping the hot water temperature in a hot water supply pipe at a predetermined value or higher when hot water supply is stopped.

Structure of Conventional Example and Its Problems Conventionally, there is a hot water supply apparatus of this type as shown in FIG.

In FIG. 1, the water supply heat source unit 2 to the water supply system turn 1
Water is supplied to the via the water supply pipe 3. Hot water supply heat source machine 2
The hot water produced in 1 is circulated from the hot water supply pipe 4 to the hot water return pipe 5 by the circulation pump 6, and then returns to the hot water supply heat source device 2 again via the water supply pipe 7 and the water supply pipe 3. A hot and cold water mixing valve 8 is connected in the middle of the hot water supply pipe 4, and a hot water and water mixing valve 8 is also connected to a hot water supply pipe 7 for supplying water from the cistern 1 to mix hot water and water. The mixed hot water mixed is supplied from the hot water taps 9 and 10 through the hot water feed pipe 4. Reference numeral 11 denotes a flow switch, which determines whether the hot water taps 9 and 10 are open or closed as a flow rate value.

As an operation, first, when the hot water taps 9 and 10 are closed, the flow switch 11 detects that the flow rate is low, lowers the capacity of the circulation pump 6, and circulates at low pressure. When the hot water taps 9 and 10 are opened, the flow switch 11 detects that the flow rate is large and causes the circulation pump 6 to circulate under pressure. Hot water tap 9, 10
The rest of the hot water supplied in step 1 returns to the hot water supply heat source device 2 through the hot water supply return pipe 5. The hot and cold water mixing valve 8 mixes and supplies hot water from the hot water supply heat source device 2, circulating hot water from the hot water supply return pipe 5 and water from the water supply pipe 7.

Since the conventional circulation device is configured as described above, it has the following problems.

(1) Since the hot water is constantly circulated, the heat radiation loss from the hot water supply pipe 4 and the hot water return pipe 5 is large, and the circulation pump 6 also requires a large amount of energy for consuming electric power.

(2) Since the hot water supply return pipe 5 and the circulation pump 6 are essential, the equipment cost is high and the piping work is complicated.

(3) At the time of hot water supply, the hot and cold water mixing valve 8 is used to supply the hot water supply heat source device 2
Since the hot water from the hot water supply, the water from the hot water supply pipe 7 and the circulating hot water from the hot water supply return pipe 5 are mixed, a low temperature cannot be obtained and the hot water supply temperature is limited.

An object of the present invention is to solve such a conventional problem, and to provide a hot water supply apparatus capable of realizing instant hot water supply and prevention of freezing without using a circulation circuit or a circulation pump and capable of adjusting a hot water supply temperature. The purpose is to

In order to achieve this object, the present invention provides a ratio control valve for adjusting a mixing ratio of hot water and water in which a hot water supply pipe and a water supply pipe are connected,
Mixed hot water temperature detector for detecting mixed hot water temperature, mixed hot water temperature setter for setting mixed hot water temperature, control valve for discharging / stopping mixed hot water, mixed hot water temperature setter and mixed hot water temperature detector When the hot water supply is not in use, the control unit controls the opening and closing of the control valve based on the signal from the mixed hot water temperature detector, and when the hot water supply is not in use, the control valve is opened. The hot water supply device is configured with a controller having a control unit that causes the ratio control valve to face a preset position, and when the hot water supply is not used, the control valve is opened based on the signal from the mixed hot water temperature detector, and the hot and cold water mixing valve is opened. By presetting the valve position of, for example, when the water side is fully closed or the position where the ratio of hot water to water is 1: 2, cold mixed hot water or hot water or water is discharged and instantaneous hot water supply or This is to prevent freezing.

Description of Embodiments Next, embodiments of the present invention will be described with reference to FIGS. 2 and 3.

In FIG. 2, a hot water supply pipe for supplying hot water from the hot water supply heat source device 12
13 and a water supply pipe 14 are connected to a hot and cold water mixing valve 15, and the hot water mixed by the hot and cold water mixing valve 15 is supplied from a terminal hot water supply port 16. Downstream of the hot and cold water mixing valve 15, there are provided a hot water thermistor 17, which is a hot water mixing detector of the hot and cold water mixing valve 15, and a control valve 18 for discharging and stopping the hot and cold water mixing. The control valve 18 and the hot and cold water mixing valve 15 is controlled by the controller 19. Further, 20 is a mixed hot water temperature setting device of the hot and cold water mixing valve 15.

FIG. 3 shows the details of the hot and cold water mixing valve 15 and the control valve 18. The hot and cold water mixing valve 15 is an automatic temperature control type. From the ratio control valve 21 for adjusting the mixing ratio and the hot water temperature thermistor 17 which is a mixed hot water temperature detector for obtaining a signal for adjustment and the mixed hot water temperature setter 20 described above. Composed. In the ratio control valve 21, the hot water valve body 22 and the water valve body 23 are
The valve shaft 24 is provided outside the stepping motor 24 by being urged outward by the springs 25 with both ends regulated.
It is driven by a gearbox 27 by 26. Then, the temperature set by the mixed hot water temperature setting device 20 and the temperature detected by the hot water temperature thermistor 17 are compared by the controller 19, and the ratio control valve 21 is adjusted to a mixing ratio at which the set temperature is obtained. The control valve 18 has a valve body 28 that opens and closes a flow path attached to a valve shaft 29,
The valve shaft 29 is driven via a gear box 31 by a motor 30 which is circumscribed. The temperature signal detected by the hot water temperature thermistor 17 is used for controlling the hot water mixing valve 15 and the control valve 18. The controller 19 controls the ratio control valve 21 by comparing the signal from the mixed hot water temperature setting device 20 with the signal from the hot water thermistor 17, and the control that opens and closes the control valve 18 by turning on and off a switch (not shown). And the hot water thermist 17 when not using the hot water supply
And a ratio control valve 21 when the control valve 18 is opened when hot water supply is not used.
And a time limit control unit.

Next, the operation of this embodiment will be described. After setting the temperature with the mixed hot water temperature setting device 20 and turning on a switch (not shown), the control valve 18 is opened by the controller 19, and the hot and cold water mixing valve 15
Adjusts the mixing ratio of hot water and water so that the temperature set by the mixed hot water temperature setting device 20 can be obtained, and hot water as set is supplied from the terminal hot water supply port 16. When the mixed hot water temperature setting device 20 is turned off, the control valve 18 is closed and hot water supply is stopped. When the temperature around the hot water thermistor 17 falls below the set value due to natural heat dissipation while hot water supply is stopped, the control valve 18 is forcibly opened by the controller 19 and the cold mixed hot water and hot water supply pipe 13 are closed. Hot water is discharged from the terminal hot water supply port 16. When the hot water from the hot water supply heat source 12 is filled in the hot water supply pipe 13 instead of the cold hot water in the hot water supply pipe 13, and the temperature around the hot water temperature thermistor 17 rises above the set temperature, the control valve 18 controls the controller. Closed by 19. When the hot water supply is not used, in the ratio control valve 21, the hot water side valve body 22 is fully opened and the water side valve body 23 is fully closed. That is, when the cold water is discharged, the water is not mixed and discharged. In this way, the hot water supply pipe 13 is always filled with hot water so that hot water of a desired temperature can be obtained immediately when hot water supply is restarted.

The above control is the operation for instantaneous hot water supply, but this hot water supply device can also be used for freeze prevention.

That is, when the temperature detected by the hot water temperature thermistor 17 falls below a predetermined value, the control valve 18 is opened, and the cold mixed hot water, the hot water in the cold hot water supply pipe 13, and the cold water supply pipe 14 are opened.
The water inside is discharged from the hot water supply terminal port 16 and can be replaced with hot water or water having a higher temperature, so that it becomes possible to prevent freezing. In this antifreezing operation, the ratio control valve 21 faces the predetermined 1: 2 positions of the hot water valve body 22 and the water side valve body 23, and the control valve 18 is opened to allow both hot and cold water to flow. Are discharged to prevent freezing of both sides. Regarding the ratio of hot water to water, since water is colder, more water is discharged in the sense of promoting flow. In order to set the position of the hot and cold water mixing valve 21 to a predetermined position, a stepping motor 26 is used to count the pulses from the point where the valve is fully opened or fully closed (detected by a micro switch or the like), or the volume for detecting the valve position or There is a method of providing an encoder or the like. Controller 19
Since it has a timed control function, by setting the time zone to operate for both instant hot water supply and anti-freezing applications, it will operate only for the required time without stopping discharge of hot water or water at all times. Energy can be saved.

Further, although the hot-water mixing valve 15 is an electrically driven automatic temperature control type in this embodiment, it may be a mechanical automatic temperature control type using a bimetal, a wax thermometer, or the like, or a manual type.

Advantageous Effects of Invention The present invention has a ratio control valve for adjusting the mixing ratio of hot water and water,
Mixed hot water temperature detector for detecting mixed hot water temperature, mixed hot water temperature setter for setting mixed hot water temperature, control valve for discharging / stopping mixed hot water, mixed hot water temperature setter and mixed hot water temperature detector The control unit that adjusts the ratio control valve by comparing the signals of 1. and the control unit that controls the opening and closing of the control valve based on the signal of the mixed hot water temperature detector when the hot water supply is not used and the opening of the control valve when the hot water supply is not used Since the controller is sometimes provided with a controller having the ratio control valve facing a preset position, it has the following effects.

(1) When the hot water supply is not in use, the controller controls the opening and closing of the control valve based on the signal from the mixed hot water temperature detector so that, for example, cold mixed hot water, cold hot water, or completely cold water can be discharged. This makes it possible to instantly supply hot water and prevent freezing.

(2) Instant hot water supply and freeze prevention can be realized with a simple structure without using a circulation circuit or circulation pump. Also, since there is no hot water supply return pipe as in the past, energy saving by reducing heat dissipation loss and wide area by ratio control valve It is possible to control the hot water supply temperature over a wide range.

(3) When the control valve is opened when the hot water supply is not in use, the hot and cold water mixing valve faces a preset position to discharge the hot water on the hot water side for instantaneous hot water supply and to prevent freezing. Both hot water and cold water can be discharged according to their respective purposes, such as the discharge of cold water or the water that has cooled completely, and reliable instantaneous hot water supply and prevention of freezing can be achieved.

[Brief description of drawings]

FIG. 1 is a system diagram showing a conventional hot water supply apparatus, FIG. 2 is a system diagram showing an embodiment of the present invention, and FIG. 3 is a sectional view showing the main parts of a ratio control valve and a control valve. 12 ... Hot water supply heat source device, 13 ... Hot water supply pipe, 14 ... Water supply pipe, 17 ... Hot water temperature thermistor (mixed hot water temperature detector), 18 ... Control valve, 19 ... Controller, 20 ... Mixed hot water temperature setter, 21 ... Ratio Control valve.

Claims (1)

[Claims] 1. A ratio control valve for adjusting a mixing ratio of hot water and hot water connected to a hot water supply pipe, a mixed hot water temperature detector for detecting a mixed hot water temperature, and a mixed hot water temperature for setting a mixed hot water temperature. Setting device,
A control valve for discharging / stopping the discharge of the mixed hot water, a control unit for comparing the signals of the mixed hot water temperature setting device and the mixed hot water temperature detector to adjust the ratio control valve, and the mixed hot water when the hot water supply is not used. From a controller having a control unit that controls opening and closing of the control valve based on a signal from a temperature detector and a control unit that causes the ratio control valve to face a preset position when the control valve is opened when hot water is not used Hot water supply equipment.