JP2638638B2 - Hot water storage type electric water heater - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hot-water storage type electric water heater that includes a plurality of hot-water storage tanks and can be installed on a narrow site.

[Prior Art] When the capacity of a hot water storage type electric water heater is increased by using one hot water storage tank, the diameter or height of the hot water storage tank is increased. However, if the hot water storage tank is made large in this way, it cannot be installed in a place where the width dimension and the height dimension are limited. Therefore, as shown in Japanese Utility Model Laid-Open No. 63-196047,
There has been proposed a relatively large-capacity electric water heater in which a plurality of hot water storage tanks are juxtaposed and can be installed even in a place where the width dimension and the height dimension are short. In the electric water heater disclosed in the publication, a hot water supply port of one hot water storage tank is connected to a water supply port of the other hot water storage tank by a connecting pipe, and the hot water storage tanks are connected in series.

[Problems to be Solved by the Invention] However, when a plurality of hot water storage tanks are connected in series using a connecting pipe, the following problem occurs.

(A) When the hot water storage tanks are connected in series, the piping path becomes long, and the large-diameter hot water storage tank and the small-diameter connecting pipe are alternately arranged between the water supply pipe and the hot water supply pipe.
There is a problem that the hot water supply pressure is reduced.

(B) The connecting pipe connecting the hot water supply port of one of the hot water storage tanks has an L-shaped bent portion at an upper portion and a lower portion,
Performing the air accumulates between the upper bent portion and the hot water supply port of one of the hot water storage tank, water flow is hindered by the air layer, the pressure of the water at reduced pressure at a pressure reducing valve (0.6kg / cm ^2), a hot water supply There is a problem that can not be done. To prevent this,
An air vent valve may be provided near the bent portion above the connecting pipe, but in this case, there is a problem that the number of parts increases.

Accordingly, a technique has been proposed in which a plurality of hot water storage tanks are arranged in parallel and the respective hot water storage tanks are connected in parallel, such as a hot water storage type water heater disclosed in Japanese Utility Model Laid-Open Publication No. 51-163564. However, in the conventionally proposed technology, the hot water storage tanks are simply connected in parallel, and there has been no study on the effective use of the hot water in the hot water storage tanks connected in parallel. For this reason, the fluid resistance of each flow path from the water supply pipe to the hot water supply pipe through each hot water storage tank was varied. The low fluid resistance in the flow path from the water supply pipe to the hot water supply pipe through the hot water storage tank means that the amount of hot water supplied from the hot water storage tank in the flow path to the hot water supply pipe is large. Conversely, a high fluid resistance in the flow channel means that the amount of hot water supplied to the hot water supply pipe from the hot water storage tank in the flow channel is small. In other words, the hot water in each hot water storage tank is used in inverse proportion to the fluid resistance of the flow path from the water supply pipe to the hot water supply pipe through the hot water storage tank. For this reason, hot water is lost in order from the hot water storage tank located in the flow path with a small fluid resistance, and thereafter water flows out of the hot water storage tank where the hot water has been lost, and water is mixed with the hot water discharged from the hot water storage tank where the hot water remains. To be supplied to the hot water supply pipe. Therefore, there was a problem that hot water in each hot water storage tank could not be used effectively.

The object of the present invention is that even when a plurality of hot water storage tanks are juxtaposed, the hot water supply pressure does not decrease, the hot water in each hot water storage tank can be used effectively, and one electric heater is used. An object of the present invention is to provide a hot water storage type electric water heater that can heat the inside of a plurality of hot water storage tanks by using the hot water storage tank and increase the utilization rate of each hot water storage tank.

Another object of the present invention is to provide an electric water heater that can easily re-fire or instantly heat water even when a plurality of hot water storage tanks are juxtaposed.

Means for Solving the Problems The present invention provides a hot water storage type electric water heater having a plurality of hot water storage tanks having a water supply port at a lower part and a water supply port at an upper part arranged side by side. To achieve.

In the present invention, the water supply ports of the plurality of hot water storage tanks are connected to each other via the first connection pipe. The hot water supply ports of the plurality of hot water storage tanks are connected to each other via the second connecting pipe. Then, a water supply pipe is connected to the first connection pipe, and a hot water supply pipe is connected to the second connection pipe. In particular, in the present invention, the fluid resistance of each flow path from the water supply pipe to the hot water supply pipe through each hot water storage tank is made substantially equal. Furthermore, in the present invention, the electric heater is disposed in one hot water storage tank,
And making the inner diameter of the second connecting pipe larger than the inner diameter of the water supply pipe or the hot water supply pipe, and convection the hot water into each hot water storage tank through the first and second connecting pipes, thereby making the hot water storage tanks hot water. It is to be filled with.

Further, the tank bodies of the plurality of hot water storage tanks may be connected to each other by a third connection pipe, and an auxiliary electric heater may be provided in an upper counter flow path passing through the third connection pipe.

[Operation of the Invention] When a plurality of hot water storage tanks are connected in parallel using the first and second connecting pipes, the hot water supply water pressure may be reduced as compared with a case where a plurality of hot water storage tanks are connected in series. In addition, since there is no need to pipe the connecting pipe downward from above, there is no possibility that air is accumulated in the connecting pipe and hot water supply becomes impossible.
In particular, in the present invention, since the fluid resistance of each flow path from the water supply pipe to the hot water supply pipe through each hot water storage tank is substantially equal, even when a plurality of hot water storage tanks are connected in parallel, Can be made substantially equal, and the hot water in each hot water storage tank can be used effectively.

By arranging the electric heater in one hot water storage tank and causing hot water to convect in each hot water storage tank through the first and second connecting pipes, it is possible to completely fill each hot water storage tank with hot water, The use efficiency of the tank can be improved.
In addition, since only one electric heater needs to be periodically inspected, inspection and electric wiring are facilitated. In addition, since the processing cost of the hot water storage tank is reduced and the cost of the electric heater is reduced, the price of the water heater can be significantly reduced.

Furthermore, if a short counter flow path is formed above a plurality of hot water storage tanks using the third connecting pipe and the auxiliary electric heater, even when a plurality of hot water storage tanks are connected in parallel, additional reheating or instantaneous heating is possible. A water heater can be performed.

Embodiment FIG. 1 shows a schematic configuration of an embodiment of the present invention. In the figure, reference numerals 11 and 12 denote cylindrical first and second hot water storage tanks arranged in an upright state in an outer case (not shown), and these hot water storage tanks 11 and 12 are provided with water supply ports 11a and 12a at a lower portion. And hot water supply ports 11b and 12b at the top. Water inlet 11a for hot water storage tanks 11 and 12
And 12a are connected to each other by a first connecting pipe 13, and hot water supply ports 11b and 12b are connected to each other by a second connecting pipe 14. A water supply pipe 5 such as a water pipe is connected to an end of the first connection pipe 3 located on the first hot water storage tank 1 side, and an end of a second connection pipe 14 located on the second hot water storage tank 12 side. A hot water supply pipe 6 is connected to the section. Electric heaters 18 are provided below the inside of the hot water storage tank 12, respectively.

In the above embodiment, the first and second hot water storage tanks 11 and 12 have the same inner diameter and height, and the first and second connecting pipes 13 and 14 also have the same inner diameter and length. Accordingly, the fluid resistance of the flow path A from the outlet of the water supply pipe 5 to the inlet of the hot water supply pipe 6 through the hot water storage tank 11 and the connection pipe 14,
The fluid resistance of the flow path B from the outlet of the water supply pipe 5 to the inlet of the hot water supply pipe 6 through the connecting pipe 13 and the hot water storage tank 12 is substantially equal. Therefore, even when two hot water storage tanks are connected in parallel, the amount of hot water supplied from each hot water storage tank becomes substantially equal, and the hot water in each hot water storage tank can be used effectively.

In this embodiment, the inner diameters of the first and second connecting pipes 13 and 14 are larger than the inner diameters of the water supply pipe 5 and the hot water supply pipe 6. Specifically, the inside diameter of the connecting pipe is about 2.5 times that of the water supply pipe. In addition, the upper portions of the inner wall surfaces of the connecting pipe 14 and the hot water supply pipe 6 are made to coincide with each other (to be flush with each other), thereby preventing the formation of air pockets between the connecting pipe 14 and the hot water feeding pipe.

In the present embodiment, the electric heater 18 is heated by midnight power to heat the water in both hot water storage tanks 1 and 2 to a predetermined temperature. When hot water is discharged from the hot water supply pipe 6, water is supplied from the water supply pipe 5 for the amount of hot water supplied. When an electric heater is arranged in each of the hot water storage tanks 11 and 12 and energized and heated at the same time, a portion below the electric heater arranged in each of the hot water storage tanks cannot be heated. Therefore, the utilization rate of the hot water storage tank cannot be 100%. In addition, when the electric heater is provided in each hot water storage tank, there is a problem that processing of the hot water storage tank becomes troublesome and processing cost increases.
Also, as the number of electric heaters increases, maintenance becomes more troublesome, and an extra inspection space for inspecting the electric heaters provided in each hot water storage tank is required.

On the other hand, in the present embodiment, when the electric heater 18 is energized to perform heating, the heated water starts convection along the path indicated by the dashed arrow. As a result, the cold water in the first hot water storage tank 11 flows from the water supply port 11a through the first connection pipe 13 into the second hot water storage tank 12, and is heated. According to the present embodiment, the entire inside of both hot water storage tanks 11 and 12 can be filled with warm water having a substantially uniform temperature. According to experiments, the feedwater temperature is 10 ℃
At this time, when the 4.4 kW electric heater is energized for about 7 hours with midnight power and heated, the hot water temperature near the water inlet of the first hot water storage tank 11 and the hot water temperature near the hot water inlet of the second hot water storage tank 12 Was about 3 to 4 ° C. For comparison, pipes having the same inner diameter as the water supply pipe 5 and the hot water supply pipe 6 were used as the first and second connection pipes 13 and 14, and the same experiment was performed. ℃. From this result, in order to make convection between both hot water storage tanks sufficient,
It is preferable to increase the inner diameter of the connecting tubes 13 and 14 as much as possible.

When the electric heater is provided only in one of the hot water storage tanks, the wiring of the electric heater is simple, and the cost for the electric heater can be reduced. By the way, even if the wattage doubles, the price of the electric heater does not double. Therefore, according to the present embodiment, it is possible to reduce the price of the electric water heater as compared with the related art.

FIG. 2 shows a modification of the embodiment of FIG. This embodiment is obtained by adding a reheating function and an instantaneous water heating function to the water heater of the embodiment shown in FIG. In the present embodiment, the tank main body of the first hot water storage tank 21 and the tank main body of the second hot water storage tank 2 are connected by a third connection pipe 20.
In the present embodiment, the mounting position of the third connection pipe 20 is set to a position of about 1/4 from above the tank body, but this mounting position can be determined as appropriate. Auxiliary electric heater 19
Are disposed above the connection position of the third connection pipe 20. Use the hot water when the temperature of the hot water heated by energizing the electric heater 18 with late-night electric power decreases due to a decrease in the environmental temperature or the passage of time, or before the hot water temperature in the hot water storage tank is heated to a desired temperature. In this case, the auxiliary electric heater 19 may be energized. When the auxiliary electric heater 19 is energized, the heated hot water convects through the upper convection flow path indicated by the dashed line,
Hot water heated by the auxiliary electric heater 19 accumulates in the first and second hot water storage tanks 21 and 22 which are positioned above the auxiliary electric heater 19.

When heating using only the electric heater 18 without using the auxiliary electric heater 19, convection occurs not only through the second connecting pipe 14 but also through the third connecting pipe 20,
There is virtually no effect.

According to the present embodiment, by adding the additional heating or the instant water heating function, the usability is further improved as compared with the first embodiment.

Although each of the above embodiments has two hot water storage tanks, the present invention can of course be applied to a case where two or more hot water storage tanks are connected in parallel.

In the above embodiment, the hot water storage tanks and the connecting pipes have the same shape in order to make the fluid resistance of each flow path from the water supply pipe to the hot water supply pipe through each hot water storage tank substantially equal. However, in order to make the fluid resistance of the flow path substantially equal,
It is not always necessary to make each hot water storage tank and the connecting pipe the same shape.For example, when the inner diameter of one hot water storage tank is small, it is possible to make a part of the connecting pipe thick and make the fluid resistance of the flow path substantially equal. it can.

[Effects of the Invention] According to the present invention, since the fluid resistance of each flow path from the water supply pipe to the hot water supply pipe through each hot water storage tank is made substantially equal, even when a plurality of hot water storage tanks are connected in parallel. , The amount of hot water from each hot water storage tank can be almost equal,
Hot water in each hot water storage tank can be used effectively.

In particular, the electric heater is arranged in one hot water storage tank,
If hot water is made to convect in each hot water storage tank through the first and second connection pipes, all the hot water storage tanks can be filled with hot water, and the use efficiency of the tanks can be improved.

Further, if the third connecting pipe and the auxiliary electric heater are used,
Even when a plurality of hot water storage tanks are used, there is an advantage that additional heating or instant water heating can be easily performed.

[Brief description of the drawings]

FIG. 1 shows a schematic configuration of one embodiment of the present invention, and FIG. 2 shows a schematic configuration of another embodiment of the present invention. 11,12,21,22, ... hot water storage tank, 13 ... first connecting pipe, 14
… Second connecting pipe, 5… water supply pipe, 6… hot water supply pipe, 18…
... electric heater, 19 ... auxiliary electric heater.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junichi Nishimura 2150, Shioi Road, Fukuma-cho, Munakata-gun, Fukuoka Prefecture Inside Kyushu Transformer Co., Ltd. No. 2150 1 Kyushu Transformer Co., Ltd. (72) Noriyoshi Nakayama Inventor 2150 No. 1 Shioido, Fukuma-cho, Munakata-gun, Fukuoka Prefecture 1 Kyushu Transformer Co., Ltd. (56) References , U) Japanese Utility Model 1-106856 (JP, U) Japanese Utility Model 2-103648 (JP, U)

Claims (2)

(57) [Claims] 1. A hot water storage type electric water heater comprising a plurality of hot water storage tanks having a water supply port at a lower portion and a water supply port at an upper portion, wherein the water supply ports (11a, 12a) of the plurality of hot water storage tanks are provided. The hot water supply ports (11b, 12b) of the plurality of hot water storage tanks are connected to each other via a second connection pipe (14). A water supply pipe (5) is connected to the first connection pipe (13), a hot water supply pipe (6) is connected to the second connection pipe (14), and one electric heater (18) is provided. The inside diameter of the first and second connecting pipes (13, 14) is arranged in the hot water storage tank (12, 22), and is larger than the inside diameter of the water supply pipe (5) or the hot water supply pipe (6). The fluid resistance of each flow path from the water supply pipe (5) to the hot water supply pipe (6) through each of the hot water storage tanks (11, 12, 21, 22) is substantially equal. Storage-type electric water heater. 2. The tank body of the plurality of hot water storage tanks (21, 22) is connected to each other by a third connecting pipe (0).
The hot water storage type electric water heater according to claim 1, wherein an auxiliary electric heater (19) is provided in an upper counter flow path passing through the connecting pipe (20).