JP2000111160A - Bypass mixing system of hot water supplier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a hot water supplier exhibit its appliance capacity effectively, by enabling the coordination between the bypass percentage and the total quantity of water simply without unnecessary ripple of temperature at the outlet of an inner drum. SOLUTION: The water governor 11 of a water supply pipe 2 is equipped with a mobile valve body 16 which can control the total quantity of water by regulating the aperture of the valve seat 15 of a fixed valve body 14, and a pressure receiver 18 where a water passage hole 19 is made is fixed downstream of the mobile valve body 16. Moreover, the bypass pipe 22 connected between the water supply pipe 2 and a hot water delivery pipe 5 is connected between the pressure receiver 18 and the valve seat 15 of the fixed valve body 14, and the bypass pipe 22 is provided with a bypass throttle valve 25 which operates by the shape memory alloy 27 sensing the temperature of incoming water and changing the load, and varies the aperture of a throttle passage 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting a bypass passage for bypassing a heat exchanger between a water supply passage connected to a heat exchanger and a tap water passage, and for controlling the amount of water from the bypass passage to the tap water passage. The present invention relates to a bypass mixing type water heater in which the temperature of an inner body outlet from a heat exchanger can be controlled within a predetermined range by controlling the same.

[0002]

2. Description of the Related Art The above-described bypass mixing type water heater controls the amount of water in the bypass passage by controlling the amount of water in the bypass passage to adjust the ratio of the amount of water flowing through the bypass passage to the total amount of water supplied to the appliance, that is, the bypass ratio. The temperature of hot water (hereinafter referred to as “inner body outlet temperature”) is controlled within a range from a lower limit temperature (for example, 46 ° C.) at which drainage is not generated in the heat exchanger to an upper limit temperature (for example, 85 ° C.) at which boiling does not occur. It is intended to be. As a mode of controlling the amount of water in the bypass passage, as disclosed in Japanese Patent Application Laid-Open No. 9-222263, the resistance in the bypass passage is varied in conjunction with a shape memory alloy spring that changes the load at the incoming water temperature. In addition to providing a bypass throttle valve, it comprises a pressure receiving body that operates by the pressure of water or hot water supplied into the appliance, and a movable valve body that variably controls the total amount of water into the appliance in conjunction with the pressure receiving body. There is known an invention adopting a water temperature sensitive type constant flow valve in which a total water amount is simultaneously changed by a stroke of a bypass throttle valve in combination with a constant flow valve.

[0003]

According to the above-mentioned invention, when the incoming water temperature is low, the total water amount and the bypass ratio can be kept low, while when the incoming water temperature is high, the total water amount and the bypass ratio become low. Will be increased. Therefore, even when the incoming water temperature is low and the set temperature is high, the inner trunk outlet temperature does not become too high. Conversely, even when the incoming water temperature is high and the set temperature is low, the inner trunk outlet temperature does not tend to be too low. However, in the above-described water temperature-responsive constant flow valve, since the amount of water to the heat exchanger side is adjusted by the movable valve body after the total amount of water is adjusted by the operation of the bypass throttle valve, the total amount of water changes. The amount of water to the heat exchanger also changes at the same time, and the temperature of the inner body outlet tends to be unnecessarily fluctuated. Even if an appropriate bypass ratio is set, there is a possibility that the temperature exceeds the boiling limit or the drain limit. In addition, the control of the total water amount is performed mainly by the bypass throttle valve, so that the total water amount is reduced, and the tool capacity cannot be sufficiently exhibited. Further, the combination structure of the bypass throttle valve and the constant flow valve becomes complicated, and the manufacturing cost is increased.

[0004] In view of the above, the first aspect of the present invention allows the bypass ratio and the total water amount to be adjusted with a simple configuration without unnecessary fluctuation of the inner body outlet temperature, and effectively controls the total water amount. It is an object of the present invention to provide a bypass mixing-type water heater that can effectively exert the appliance capability as much as possible.

[0005]

According to a first aspect of the present invention, the pressure receiving member is disposed closer to the heat exchanger than the movable valve element, and the pressure receiving member is disposed on the pressure receiving member. While providing a through hole to fix the amount of water to the heat exchanger,
A bypass throttle valve that connects the bypass passage between the pressure receiving body and the control position of the total water amount by the movable valve body, and that is capable of controlling a water amount in the bypass passage; A heat responsive member that operates in accordance with the temperature of the water flowing through the passage and interlocks the bypass throttle valve, and changes the pressure on the pressure receiving body by controlling the amount of water in the bypass passage by the bypass throttle valve; It is characterized in that the total water volume can be controlled. In addition to the object of the first aspect, the invention described in claim 2 ensures a wider range of adjustment of the bypass ratio to improve drain prevention and boiling prevention performance, and also enables the total water amount to be controlled more. In addition, an electromagnetic valve that opens and closes at a predetermined set temperature is provided in the bypass passage.

According to the third aspect of the present invention, in addition to the object of the first aspect, it is possible to secure a wider adjustment range of the bypass ratio, improve the drain prevention and the boiling prevention performance, and control the total water amount more. To provide a parallel path bypassing the bypass throttle valve in the bypass path, in the parallel path,
An electromagnetic valve that opens and closes at a predetermined set temperature is provided. According to the invention of claim 4, in addition to the object of claim 1, it is possible to secure a wider adjustment range of the bypass ratio, improve drain prevention and boiling prevention performance, and control the total water amount to almost the maximum equipment capacity. In order to provide a return passage that joins the flow of hot water or water passing through the heat exchanger in the bypass passage, the flow rate of the return passage is also variably controlled by a second valve body provided in the bypass throttle valve, A parallel path that opens between both valve bodies of the bypass throttle valve is provided in parallel with the bypass path, and an electromagnetic valve that opens and closes at a predetermined set temperature is provided in the parallel path.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. << Mode 1 >> FIG. 1 schematically shows a bypass mixing type water heater (hereinafter abbreviated as “water heater”).
Is a water supply pipe 2 connected to the water supply and having a water supply channel therein,
The heat exchanger 4 includes a heat exchanger 4 for heating water guided from the water supply pipe 2 by a gas burner 3, and a tapping pipe 5 internally provided with a tapping path for sending out hot water heated by the heat exchanger 4. In addition, the water supply pipe 2 is provided with a water amount sensor 6 for detecting a water amount, a water temperature sensor 7 for detecting an incoming water temperature, and the tap water pipe 5 is provided with a tap water temperature sensor 8 for detecting a tap water temperature. It is electrically connected to the controller 9. This controller 9
Is a proportional control valve provided in a gas flow path to the gas burner 3 so that hot water is discharged at a set temperature selected by a user with the remote controller 10 based on detection signals obtained from the incoming water temperature sensor 7 and the outgoing water temperature sensor 8. A known hot water temperature control such as controlling an opening degree (not shown) is performed.

The water supply pipe 2 is provided with a water governor 11 as a constant flow valve. A governor body 12 is formed in the water governor 11 on the downstream side of the water amount sensor 6, and a cup-shaped fixed valve body 14 in which water passages 13 are formed is fixed in the governor body 12. Inside the body 14,
A cup-shaped movable valve body 16 capable of changing the degree of opening between the fixed valve body 14 and the valve seat 15 is arranged in a manner that the opening of the cup-shaped movable body 16 is opposite to that of the fixed valve body 14. The movable valve body 16 is provided with a sealing member 17 in the governor body 12 on the downstream side of the fixed valve body 14.
Ring-shaped pressure receiving body 1 slidably provided through
8 and a coil spring 21 disposed between the pressure receiving body 18 and a spring retainer 20 on the downstream side thereof.
It is urged upstream. The pressure receiving body 18 has a plurality of water passage holes 19 formed therein.
8 is connected to the downstream side.

On the other hand, between the water supply pipe 2 and the tapping pipe 5, a bypass pipe 22 having a bypass passage for bypassing the heat exchanger 4 is connected. This bypass pipe 22 is connected to the water supply pipe 2.
On the side, the pressure receiving body 18 and the fixed valve body 14 in the water governor 11
To form a communication passage 23. The bypass pipe 22 is provided with a bypass throttle valve 25 which is loosely fitted to the valve guide 24 and is slidable so that the opening degree of the throttle passage 26 in the bypass pipe 22 can be changed. The bypass throttle valve 25 is a bias which is a normal coil spring disposed opposite to the shape memory alloy spring 27 between the valve guide 24 and the shape memory alloy spring 27 as a thermally responsive member disposed downstream thereof. The stroke is determined by the balance with the spring 28. That is, the shape memory alloy spring 27 that senses the temperature of water entering the bypass pipe 22
However, as the incoming water temperature increases, the load increases and the throttle passage 2
Although the opening degree of No. 6 is increased, specifically, the setting is such that the bypass ratio is changed to a maximum of 27% in the range of the inlet water temperature of 1 ° C to 30 ° C.

In the water heater 1 configured as described above, the bypass pipe 2 is connected from the water governor 11 through the communication passage 23.
When the shape memory alloy spring 27 reacts to the incoming water temperature flowing into the inside 2 to control the stroke of the bypass throttle valve 25 to vary the opening of the throttle passage 26, the pressure change is caused by the change in resistance due to the change in the opening. The water pressure applied to the body 18 changes, and the stroke of the movable valve body 16 in balance with the coil spring 21, that is, the valve seat 15 of the fixed valve body 14 by the movable valve body 16.
Is determined, and the total amount of water flowing to the water heater 1 is determined. This relationship is expressed as follows:
The area of the pressure receiving body 18 is A, the area of the water holes 19 and 19 is a,
Assuming that the area of the throttle passage 26 is b and the spring load of the coil spring 21 is W, the following expression 1 can be obtained.

[0011]

(Equation 1)

As described above, in the water heater 1, the pressure receiver 1
8, the flow rate to the heat exchanger 4 is fixed by the water flow holes 19, 19, and the area b of the throttle passage 26 is increased by the bypass throttle valve 25, so that the total water amount Q increases together with the bypass rate. That is, by setting the structure of the water governor 11 and the setting of the connection position of the bypass pipe 22 to the structure, the bypass ratio and the total water amount can be changed without changing the flow rate to the heat exchanger 4. Unnecessary fluctuations can be prevented.
In addition, the water governor 11 is basically different in configuration from the bypass throttle valve 25 to simplify the structure, leading to a reduction in manufacturing cost. FIG. 2 is a graph showing the minimum value (left curve) and the maximum value (right curve) of the total water amount Q with respect to the tap water temperature in the water heater 1. For example, the total water amount Q when the tap water temperature is 60 ° C. (When there is no bypass pipe 22)
For the incoming water temperature, it is represented by the equation Q = 400 / (60-incoming water temperature). “400” is the heat output value (kcal / min) of the maximum thermal power of the gas burner 3. Therefore, when the incoming water temperature is 5 ° C., Q is 7.3 liter / min. But,
Here, since the bypass throttle valve 25 increases the bypass ratio to 27% and reduces the resistance at the inlet water temperature of 25 ° C., the total water amount by the water governor 11 is reduced to 10 liter / min as shown in the lower graph of FIG. It can be increased, and the tool ability can be exhibited effectively. Here, by varying the bypass ratio up to a maximum of 27%, the temperature of the inner body outlet of the heat exchanger 4 can be raised above the temperature of the hot water, which leads to an improvement in the performance of preventing generation of drainage.

In the first embodiment, the bypass throttle valve 2
Since the valve 5 is almost in the open state, if the bypass ratio is excessively increased for drainage countermeasures, there is a possibility that boiling will occur at the time of hot water supply, and the bypass ratio can be set only to 27%.
Therefore, when the incoming water temperature is high, for example, at 25 ° C., the calculated total water amount Q is 11.43 liters / min, but the appliance performance is not sufficiently exhibited. Therefore, embodiments in which the capacity can be improved by increasing the total amount of water will be described below as Embodiments 2 to 4. Since the main configuration of the water heater is the same as that of the first embodiment, only the internal structure of the bypass pipe 22 is shown, and the same reference numerals denote the same components, and a description thereof will be omitted. << Embodiment 2 >> As shown in FIG. 3, an electromagnetic valve 29 is provided downstream of the bypass throttle valve 25 in the bypass pipe 22. The solenoid valve 29 urges a plunger 31 having a diaphragm valve 30 with a coil spring 32 so as to close the bypass pipe 22 in a normal state.
The plunger 31 is retracted against the bias of the coil spring 32 and the diaphragm valve 30 opens the bypass pipe 22 by controlling the energization of the electromagnetic coil 33 by the controller 9. It will be. However, this valve opening operation is performed only when the set temperature by the remote controller 10 is lower than 50 ° C., and when the set temperature is 50 ° C. or higher, regardless of the stroke of the bypass throttle valve 25,
The solenoid valve 29 is in a closed state and the bypass ratio is always 0%.

Therefore, according to the second embodiment, a bypass ratio of 50% can be secured at a maximum below a set temperature of 50 ° C. at which there is no risk of occurrence of boiling, and a bypass ratio of 20% can be secured in a range of an inlet water temperature of 1 ° C. to 30 ° C. By changing it up to 50%, FIG.
The total water volume is 9.1 liter / min when the water temperature is 5 ° C, and the total water volume is 1 when the water temperature is 25 ° C.
It can be increased to 4.6 liters / minute, and the total amount of water increases, especially in the tapping temperature range of less than 50 ° C., as compared with mode 1, and the usability is improved. FIG. 5 is a graph showing a limit value of a bypass ratio at which the prevention of drainage and the prevention of boiling can be achieved with respect to a set temperature. The limit line, graph b, shows a boiling limit line that can maintain the inner body outlet temperature at 85 ° C or less at an inlet water temperature of 1 ° C, and graph c maintains the inner body outlet temperature at 46 ° C or more at an inlet water temperature of 30 ° C. A possible drain limit line, graph d, shows a boiling limit line at which the inner body outlet temperature can be maintained at 85 ° C. or less at an inlet water temperature of 30 ° C. Therefore, if the bypass ratio is set in the overlap region between the graphs a and b and the graph c and d (the hatched portion A in the figure), the incoming water temperature is 1 ° C. to 30 ° C. and the set temperature is 38 ° C. to 70 ° C.
Although both the prevention of drainage and the prevention of boiling can be achieved over the range of ° C, in the second embodiment, the bypass ratio is variable in the range of 20% to 50% when the solenoid valve 29 is opened at 48 ° C or lower. , And 48 ° C., it becomes 0%. Therefore, by setting the bypass ratio within the range, it is possible to substantially satisfy the prevention of drainage and the prevention of boiling.

<Embodiment 3> In the above-described embodiment 2, the total water amount can be increased only in a set temperature range of less than 50 ° C. at which the solenoid valve 29 is opened. The valve closes and the total water volume does not change.
Therefore, as shown in FIG. 6, it is preferable that a parallel path 34 bypassing the bypass throttle valve 25 is provided in the bypass pipe 22 in parallel, and the solenoid valve 29 is provided in the parallel path 34. For example,
The bypass ratio of the parallel path 34 due to the opening of the solenoid valve 29 is set to 23.
If the solenoid valve 29 is closed at a set temperature of 50 ° C. or higher by setting the bypass rate by the bypass throttle valve 25 to a maximum of 27% in accordance with the incoming water temperature of 1 ° C. to 30 ° C., FIG. As described above, the total water amount can be secured from 7.3 to 10 liters / min by setting the bypass throttle valve 25 side. When the set temperature is less than 50 ° C., the total water amount is 9.5 by changing the bypass ratio from 23% to 50%.ま で 14.6 l / min. In particular, in the third embodiment, as shown in the graph of FIG. 5, the bypass ratio is in the range of 23% to 50% when the solenoid valve 29 is opened at 48 ° C. or lower (shaded line B), and 0% at 50 ° C. or higher. Since it is variable within the range of 27% (hatched line C), it is possible to satisfy both drain prevention and boiling prevention by setting the bypass ratio within the range (overlapping portion of each hatched line).

<Embodiment 4> Also in Embodiment 3, when the incoming water temperature increases, a certain amount of increase in water volume can be expected, but the tool capacity cannot be maximized. Therefore, as shown in FIG. 8, a return passage 35 is formed to join the amount of water controlled by the bypass throttle valve 25 to the heat exchanger 4 downstream of the pressure receiving body 18 in the water governor 11, and the bypass throttle valve includes:
A first throttle valve 25a for controlling the amount of bypass water between the first throttle passage 26a to the bypass pipe 22 and a second throttle valve 25b for controlling the amount of water to the return passage 35 between the second throttle passage 26b. And are formed. On the other hand, it is preferable that a parallel path 36 is arranged in parallel with the bypass pipe 22 from between the first throttle path 26a and the second throttle path 26b, and the solenoid valve 29 is provided in the parallel path 36. Here, assuming that the area of the return passage 35 is b, the passage area by the first throttle valve 25a and the first throttle passage 26a is c, and the area of the parallel passage 36 by the solenoid valve 29 is c ', Has the relationship of the following equation (2), and the total water amount is as shown in FIG. 9 and Table 1.

[0017]

(Equation 2)

[0018]

[Table 1]

Therefore, according to the fourth embodiment, the return passage 3
With the aid of the amount of water to the heat exchanger 4 side by 5, the total amount of water can be further increased, and even when the incoming water temperature is high, the total amount of water can be secured to almost the maximum equipment capacity in almost the entire range of the tap water temperature. Therefore, a water heater excellent in usability can be obtained. The bypass ratio of the fourth embodiment is also determined by (c + c ′). As shown in Table 1, the bypass ratio is 0% to 27% when the set temperature is 50 ° C. or higher, and the bypass ratio is lower than the set temperature 50 ° C. Since each is determined at 23% to 50%,
As in FIG. 7 described in the third embodiment, it is understood that both the prevention of drainage and the prevention of boiling are satisfied.

In the first to fourth embodiments, the water governor 11 is used as a constant flow valve, but as shown in FIG.
The same effect can be obtained by providing a hot water governor 37 between the bypass pipe 22 and the tapping pipe 5 instead of the water governor 11. That is, a pressure receiving member 41 having water passage holes 42, 42 is continuously connected to the movable valve body 40, which can adjust the opening of the valve seat 39 of the fixed valve body 38, near the heat exchanger 4. 40 is the coil spring 4
3, the bypass pipe 22 is connected between the valve seat 39 and the pressure receiving body 41.
The arrangement of the bypass throttle valve 25, the shape memory alloy spring 27, and the like in the inside is the same as that of the other embodiments as schematically shown in FIG.

[0021]

According to the first aspect of the present invention, the bypass ratio and the total water amount can be varied without changing the flow rate to the heat exchanger by setting the connection position of the constant flow valve and the bypass path to the constant flow valve. Because of this structure, unnecessary fluctuations in the inner body outlet temperature can be prevented, and the total water volume can be increased to effectively exert the instrument capability. Furthermore, since the constant flow valve is basically different from the bypass throttle valve to simplify the structure,
This leads to a reduction in manufacturing costs. According to the second aspect of the invention, in addition to the effect of the first aspect, by providing the solenoid valve that opens and closes at a predetermined set temperature in the bypass path, a wider adjustment range of the bypass ratio is secured. Drain prevention and boiling prevention performance are improved, and the total amount of water can be controlled more.

According to the third aspect of the present invention, the first aspect is provided.
In addition to the effect of the above, a parallel path bypassing the bypass throttle valve is provided in the bypass path, and a solenoid valve that opens and closes at a predetermined set temperature is provided in the parallel path, thereby securing a wider adjustment range of the bypass ratio. As a result, the performance of preventing drainage and boiling can be improved, and the total amount of water can be controlled more. Claim 4
According to the invention described in (1), in addition to the effect of the first aspect, the bypass valve is provided with a return passage that joins the flow of hot water or water passing through the heat exchanger, and the second valve body provided in the bypass throttle valve. While the flow rate of the return passage is also variably controlled, a parallel path that opens between both valve bodies of the bypass throttle valve is provided in parallel with the bypass path, and the parallel path opens and closes at a predetermined set temperature. By providing a valve, a wider range of bypass ratio adjustment is ensured to improve drain prevention and boiling prevention performance.
It is possible to control the total water volume to almost the maximum equipment capacity.

[Brief description of the drawings]

FIG. 1 is a schematic view of a bypass mixing type water heater.

FIG. 2 is a graph showing a relationship between a tapping temperature and a total water amount in Embodiment 1.

FIG. 3 is an explanatory diagram showing an internal structure of a water governor and a bypass pipe according to a second embodiment.

FIG. 4 is a graph showing a relationship between a tapping temperature and a total water amount in a second embodiment.

FIG. 5 is a graph showing a relationship between a bypass ratio and a set temperature.

FIG. 6 is an explanatory diagram showing an internal structure of a water governor and a bypass pipe according to a third embodiment.

FIG. 7 is a graph showing a relationship between a tapping temperature and a total water amount in Embodiment 3.

FIG. 8 is an explanatory diagram showing an internal structure of a water governor and a bypass pipe according to a fourth embodiment.

FIG. 9 is a graph showing a relationship between a tapping temperature and a total water amount in mode 4.

FIG. 10 is an explanatory diagram of a hot water governor.

[Explanation of symbols]

1. Bypass mixing type water heater, 2. Water pipe, 3
..Gas burners, 4. heat exchangers, 5. hot water pipes, 9.
-Controller, 10-Remote control, 11-Water governor, 12-Governor body, 14-Fixed valve body, 16-
Movable valve body, 18 ... pressure receiving body, 19 ... water hole, 21 ...
Coil spring, 22 bypass pipe, 25 bypass throttle valve, 26 throttle passage, 27 shape memory alloy spring,
28 .. bias spring, 29 .. solenoid valve.

Claims (4)

[Claims] 1. A heat exchanger having a burner, a water supply path for supplying water to the heat exchanger, and a hot water path for sending hot water from the heat exchanger, while the water supply path and the hot water path Between, connecting a bypass to bypass the heat exchanger,
Further, in any one of the water supply path and the hot water path,
Bypass mixing provided with a constant flow valve comprising a pressure receiving body that operates by the pressure of water or hot water supplied into the appliance, and a movable valve body that variably controls the total amount of water into the appliance in conjunction with the pressure receiving body. A water heater, wherein the pressure receiving body is disposed closer to the heat exchanger than the movable valve body, and a through hole is provided in the pressure receiving body to fix the amount of water to the heat exchanger, while the bypass is provided. A path is connected between the pressure receiving body and the control position of the total water amount by the movable valve body, and the bypass path includes a bypass throttle valve capable of controlling a water amount in the bypass path, and a bypass path. A heat responsive member that operates in accordance with the temperature of the flowing water and interlocks the bypass throttle valve, and changes the pressure on the pressure receiving body by controlling the amount of water in the bypass passage by the bypass throttle valve; A bypass mixing type water heater characterized in that the total water volume can be controlled. 2. The bypass mixing type water heater according to claim 1, wherein a solenoid valve that opens and closes at a predetermined set temperature is provided in the bypass passage. 3. The bypass mixing type water heater according to claim 1, wherein a parallel path that bypasses the bypass throttle valve is provided in the bypass path, and an electromagnetic valve that opens and closes at a predetermined temperature is provided in the parallel path. 4. A return passage which joins a flow of hot water or water passing through a heat exchanger in a bypass passage, and a flow rate of the return passage is variably controlled by a second valve body provided in a bypass throttle valve. 2. The bypass mixing according to claim 1, wherein a parallel path that opens between both valve bodies of the bypass throttle valve is provided in parallel with the bypass path, and an electromagnetic valve that opens and closes at a predetermined set temperature is provided in the parallel path. Water heater.