JPH0635901B2 - Solar water heater - Google Patents

Description

TECHNICAL FIELD The present invention relates to a solar water heater, and more particularly to a solar water heater provided with a circulation pump for forcibly circulating a heat medium.

(Prior art and its problems) Conventionally, solar water heaters with circulation pumps installed in the circulation piping have a drainage valve in the circulation piping as a measure to prevent freezing of the pumps. When the temperature rises, the residual water in the pump part is discharged from the drain valve to prevent the pump part from breaking due to freezing.

However, in this conventional solar water heater, it is necessary to detect the freezing dangerous temperature of the pump section and open the drain valve, so it is extremely inconvenient to manually open the drain valve. In addition, there is a problem that the pump part is often destroyed by forgetting to open the drain valve, and the drain valve is detected by detecting a dangerous temperature of freezing of the pump part with a temperature sensor or the like. In the case of automatically opening the cap, the structure and control become complicated, and there is a problem that the solar water heater as a product becomes expensive.

In order to solve this problem, it has been proposed to wind an electric heater around the outer surface of the pump part and heat the pump part with the electric heater when the pump part reaches a freezing dangerous temperature, but it is still a circulation pump part. There is a problem that the structure and control are complicated and the running cost is increased because an electric heater is used.

Further, it has been proposed to install a pump section inside the hot water storage tank and to provide a motor section for driving the pump section outside the hot water storage tank to prevent the pump section from freezing. However, in this case, since the pump section and the motor section are installed at a distance from each other, a large load is applied to the motor section, and as a result, the performance of the pump section such as the flow rate and the lift is lowered. Had.

(Object of the Invention) The present invention has been devised in view of the above circumstances, and its purpose is completely reversed from the idea of preventing freezing of the pump portion of the conventional circulation pump, and rather the pump portion is prioritized. (EN) It is an object of the present invention to provide a completely new solar water heater that does not require a drain valve or complicated control in the circulation pipe and does not deteriorate the pump performance.

(Means for Solving Problems) A solar water heater according to the present invention is a solar water heater which connects a heat collector and a hot water storage tank with a circulation pipe and which is provided with a circulation pump for circulating a heat medium in the circulation pipe. In the water heater,
The circulation pump is arranged in the vicinity of the hot water storage tank, the motor portion of the circulation pump is capped with good heat conductivity, and the pump portion of the circulation pump and the hot water storage tank are covered with a heat insulating material. And

(Example) Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a partially cutaway perspective view showing an embodiment of the solar water heater of the present invention, in which 1 is a heat collector, 2 is a hot water storage tank, and 3 is for connecting the heat collector 1 and the hot water storage tank 2. Is the arm of.

The heat collector 2 is constructed by laying a heat insulating material 1b on a bottom surface and a side surface in a box-shaped casing 1a to accommodate a heat collecting plate 1c, and closing an upper end opening of the box-shaped casing 1a with a transparent plate 1d. There are two heat collectors at the center of the upper edge of the heat collector 1 and the connecting pipe 1
connected by e.

The hot water storage tank 2 is made of polyethylene resin or the like, and is housed in a case 7 made of polyethylene resin or the like via a heat insulating material 8 made of expanded polystyrene or the like.

The heat collector 1 and the hot water storage tank 2 are installed separately on both sides of the building 4a with the building 4a of the roof 4 sandwiched therebetween, and the heat collector 1 and the hot water storage tank 2 are circulation pipes housed in the arm 3. Connected by five.

In the vicinity of the hot water storage tank 2 in the circulation pipe 5, that is, in the case 7 on the back side of the hot water storage tank 2, a circulation pump 6 is arranged. By driving this circulation pump 6 by using, for example, a solar cell as a power source, the heat medium (water) in the hot water tank 2 is collected.
The structure is such that hot water is obtained by pumping to and circulating the heat medium.

As shown in FIG. 2, the circulation pump 6 is a pump unit that sucks a heat medium through a circulation pipe 5 ′ connected to the hot water storage tank 2 and pumps the heat medium to the heat collector 1 side through the circulation pipe 5. 6a
And a motor portion 6b for driving the pump portion 6a
And a pump portion 6a and a motor portion 6b.
And are continuously and integrally formed. This circulation pump 6
Is removably screwed to the bottom surface of the case 7, and the pump 6ab is covered with a heat insulating material 9 made of inorganic fiber, styrofoam, or the like. This is the pump section 6a
This is because the freezing start temperature of is reduced as much as possible.

The motor portion 6b is capped with a cap 10 made of, for example, a metal having excellent thermal conductivity such as aluminum, stainless steel, copper, iron, or a resin so as to be integrally connected to the pump portion 6a.

The cap 10 having good heat conductivity radiates the heat of the motor portion 6b during the heat collection operation (when the circulation pump is operating), and pumps when the heat collection operation is stopped (when the circulation pump is stopped), such as at night in winter. The heat of the portion 6a is positively radiated to freeze the residual water in the pump portion 6a in preference to the residual water in the circulation pipes 5 and 5 '. In this case, the pump unit 6a
The suction port of is connected to the hot water storage tank 2 by a circulation pipe 5 ', and the discharge port of the pump portion 6a is connected to the circulation pipe 5 arranged on the side surface of the hot water storage tank 2 covered with the heat insulating material 8. Therefore, even if the residual water in the pump portion 6a freezes quickly, the volume expansion of the residual water is absorbed by the circulation pipes 5 and 5'and the pump portion 6a is never destroyed by the volume expansion of the residual water. .

In order to further improve the heat dissipation of the circulation pump 6, for example, a plurality of fins may be provided on the outer surface of the cap 10 having good thermal conductivity.

(Effect of the invention) As described in detail above, according to the solar water heater of the present invention,
The circulation pump was installed near the hot water storage tank, the motor section of the circulation pump was capped with good thermal conductivity, and the pump section of the circulation pump and the hot water storage tank were covered with a heat insulating material. The residual water in the pump part can be preferentially frozen without destroying the pump, thus providing an extremely excellent solar water heater that does not require a drainage structure or complicated control and does not deteriorate the performance of the circulation pump. can do.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the solar water heater of the present invention, and FIG. 2 is a schematic view of a circulation pump of the solar water heater of the present invention. 1, heat collector 2, hot water storage tank 5, 5 ', circulation piping, 6, circulation pump 6a, pump portion, 6b, motor portion 8, 9, heat insulating material 10, cap

Claims (1)

[Claims] 1. A solar water heater comprising a heat collector and a hot water storage tank connected by a circulation pipe, and a circulation pump for circulating a heat medium in the circulation pipe. A solar water heater characterized in that it is arranged in the vicinity, a cap with good thermal conductivity is capped on the motor part of the circulation pump, and the pump part of the circulation pump and the hot water storage tank are covered with a heat insulating material.