JPS6144225B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method of manufacturing a solar water heater.

Conventional technology and its problems Conventionally, in a solar water heater, a water pipe is placed along the bottom surface of a solar heat collection plate, an upper mold with a flat bottom surface is placed along the top surface of the heat collection plate, and a predetermined distance from the heat collection plate is placed. It was manufactured by arranging a lower mold with a flat upper surface below, injecting and foaming a foamable resin insulation material between the upper and lower molds, and pressing the water pipe into contact with the heat collecting plate. However, in the conventional manufacturing method, there was a problem in that the contact area between the heat collecting plate and the water pipe in the manufactured water heater was small, resulting in poor heat transfer efficiency between the two. In addition, there is a risk that the heat insulating material may enter between the heat collecting plate and the water pipe, resulting in a problem that heat transfer between the two may not occur.

An object of the present invention is to solve the above problems and provide a method for easily manufacturing a solar water heater that has good adhesion between a heat collecting plate and a water pipe, and has excellent heat transfer between the two. It is in.

Means for Solving the Problems The method for manufacturing a solar water heater according to the present invention includes providing a required number of grooves each having a substantially U-shaped cross section on the upper surface of a heat collecting plate whose upper surface is covered with a solar heat absorbing film. , this heat collecting plate is placed above the bottom wall of the water heater case at a predetermined distance from the bottom wall, the water pipe is inserted loosely into the groove, and the top surface is placed on the lower surface of the bottom wall of the water heater case. A flat lower jig should be placed along the upper surface of the heat collecting plate, and the lower surface should be flat and the lower surface should have a protrusion that comes into contact with the upper end of the water pipe in the concave groove to prevent the water pipe from rising up. The jig should be aligned so that the lower surface of the upper jig and the upper surface of the heat collection plate are in close contact and the protrusions on the lower surface of the upper jig are within the groove, and the protrusions of the upper jig should hold down the water pipe. This method consists of injecting and foaming a foamable resin insulation material between the bottom wall of the water heater case and the heat collecting plate, and deforming the groove wall by the foaming pressure so that it adheres to almost the entire circumference of the water pipe. It is.

In the above, the water heater case used is one in which the peripheral wall and the bottom wall are integrally molded, or one in which the bottom wall is fitted into a frame-shaped peripheral wall. As the heat collecting plate, for example, one made of aluminum (including aluminum alloy) is used. In order to provide a solar heat absorbing film on the upper surface of the heat collecting plate, it is preferable to perform a solar heat selective absorption film treatment on the surface of the heat collecting plate, for example. The characteristics of the solar heat selective absorption film are preferably such that the solar absorption rate α is 0.85 or more and the emissivity ε is 0.3 or less. Incidentally, the solar heat selective absorption film is generally smooth, but in order to increase the surface area, it may have a finely wavy longitudinal section. Alternatively, a solar heat absorbing film may be formed by coating the surface of the heat collecting plate. In order to provide the required number of grooves having a substantially U-shaped cross section on the upper surface of the heat collecting plate, the heat collecting plate may be formed into a substantially corrugated plate shape, for example. Preferably, the side walls of the groove widen upward and outward. This is because it is easier to insert the water pipe into the groove in the subsequent process. The thickness of the heat collecting plate is set so that it is easily deformed by the foaming pressure of the foamable resin heat insulating material. As water pipes, aluminum pipes, copper pipes, steel pipes, etc. are used. As the foamable resin heat insulating material, foamable polyurethane resin, foamable phenolic resin, etc. are used.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, four frame members 2 made of extruded aluminum
A frame 1 is formed by assembling them into a picture frame shape. The frame member 2 has an approximately E-shaped cross section and includes a vertical wall 2a and a vertical wall 2.
Upper horizontal wall 2b that is connected to the upper edge of a and protrudes inward
, upper and lower double horizontal walls 2c and 2d that are connected to the lower edge of the vertical wall 2a and protrude inwardly, and an intermediate horizontal wall that is connected to the inner surface of the vertical wall 2a and protrudes inwardly at the middle part of the height. It consists of wall 2e. An internal enlarged groove 3 that opens upward and extends in the longitudinal direction is provided at the inner edge of the upper surface of the upper horizontal wall 2b. Also, upper horizontal wall 2
A rising part 4 extending in the longitudinal direction and having an upper end inclined outward is provided approximately at the center of the inside and outside of b. A horizontal section 5 is provided directly above the wall 2a.

Next, by fitting the peripheral edge of an aluminum plate (including an aluminum alloy plate) between the double horizontal walls 2c and 2d at the lower edge of the frame member 2, a water heater case including the frame 1 and the bottom wall 6 is constructed. Configure. Further, a groove 9 having a substantially U-shaped cross section and expanding outward with side walls facing upward is provided on the upper surface of the heat collecting plate 8 whose upper surface is covered with the solar heat absorbing film 7. The peripheral edge of the plate 8 is placed on the intermediate horizontal wall 2e, and the meandering water pipe 1 is placed in the groove 9 on the upper surface of the heat collecting plate 8.
Loosely insert the straight pipe section of 0. Then, a flat lower jig 11 with a flat upper surface is placed on the lower surface of the bottom wall 6, and a flat upper jig 12 with a flat lower surface is placed on the upper surface of the heat collecting plate 8. The water pipe 10 is placed in contact with the upper end of the water pipe 10 in the groove 9 at a position corresponding to the straight pipe part of the water pipe 10 on the lower surface of the upper jig 12.
A protrusion 12a is provided for suppressing floating of the material. The upper jig 12 is assembled in such a state that the flat part of the lower surface of the upper jig 12 and the flat part of the upper surface of the heat collecting plate 8 are in close contact with each other, and the protrusions 12a are present in the grooves 9. The protrusions 12a are deflected by the hot plate 8 and come into contact with the water pipe 10, thereby preventing the water pipe 10 from floating (see FIG. 1). In this state, a foamable resin heat insulating material is injected and foamed between the bottom wall 6 and the heat collecting plate 8 through a heat insulating material inlet 13 provided in the frame 1, thereby producing a heat insulating material 14 made of foamed plastic. Then, the foaming pressure when injecting and foaming the heat insulating material is applied to the wall of the groove 9, and the wall of the groove 9 is deformed and tightly adheres to almost the entire circumference of the water pipe 10 except for the part where it contacts the protrusion 12a. (See Figure 2).

After injection foaming, remove the upper and lower jigs 12 and 11,
A gasket 15 is attached to the internal enlarged groove 3 of the upper horizontal wall 2b of the frame 1, and the peripheral edge of the transparent glass plate 16 is placed on the gasket 15. Finally, a glass plate holding member 17 made of extruded aluminum and having a substantially square cross section is placed over the upper horizontal wall 2b. The glass plate pressing member 17 includes a horizontal wall 17a and a horizontal wall 17.
It consists of a hanging wall 17b that continues to the outer edge of a. Further, an engaging portion 18 having a triangular cross section and engaging with a portion of the horizontal portion 5 that protrudes inwardly from the rising portion 4 is provided at approximately the center of the inside and outside of the lower surface of the horizontal wall 17a to protrude downward. There is. In addition, the horizontal wall 17
A plate holding part 17c having a required width and having a horizontal lower surface is provided at the inner edge of the lower surface a, and a gasket made of an elastic material is adhered to the lower surface of this plate holding part 17c. In addition, the hanging wall 1 of the plate holding member 17
An inwardly bent portion 17d is provided at the lower edge of 7b, and the inner edge of this inwardly bent portion 17d is in contact with the left surface of the vertical wall 2a. The upper surface of the peripheral edge of the glass plate 16 is held down by a plate holding part 17c via a gasket. At this time, since the gasket 15 is compressed, its repulsive force causes the plate holding member 17 to
is pushed upward, and the engaging portion 18 and the inwardly protruding portion of the horizontal portion 5 are firmly engaged. In this way, a solar water heater is manufactured (see Figure 3).

Effects of the Invention As mentioned above, according to the manufacturing method of the present invention,
Since the water pipes can be attached to the heat collecting plate by injecting and foaming the foamable resin heat insulating material, the work is easy. Moreover, since the heat collecting plate and the water pipe are brought into close contact with each other by the foaming pressure, the bond between the two becomes strong. In addition, in the method of the present invention, a lower jig with a flat upper surface is placed along the lower surface of the bottom wall of the water heater case, and a lower jig with a flat lower surface and a groove in the lower surface is placed on the upper surface of the heat collecting plate. The upper jig is equipped with a protrusion that comes into contact with the upper end of the water pipe to prevent the water pipe from rising, and the lower surface of the upper jig is in close contact with the upper surface of the heat collecting plate, and the protrusion on the lower surface of the upper jig is inside the groove. The foaming resin insulation material is injected and foamed between the bottom wall of the water heater case and the heat collecting plate while the water pipe is held down by the protrusions, so that the water pipe is The groove wall portion of the groove in the heat collecting plate is deformed and securely adheres to almost the entire circumference of the water pipe except for the portion in contact with the protrusion, without floating and popping out from within the groove. , the heat collecting plate is in a state of enclosing the water pipe.
Therefore, the contact area between the heat collecting plate and the water pipe increases, and the adhesion between the two becomes excellent, thereby dramatically improving the heat transfer efficiency from the heat collecting plate to the water pipe. Furthermore, during the process of using this water heater, when the foamed plastic insulation material is heated, it causes secondary foaming.
The connection between the heat collecting plate and the water pipe becomes even stronger.

[Brief explanation of the drawing]

The drawings show embodiments of the invention in the order of steps, with the first
The figure is a vertical cross-sectional view before injecting and foaming the insulating material, Figure 2 is a partial vertical cross-sectional view after injecting and foaming the insulating material, and Figure 3 is a vertical cross-sectional view before injecting and foaming the insulating material.
The figure is a partial vertical sectional view of the completed water heater. 6... Bottom wall, 7... Solar heat absorption film, 8... Heat collecting plate, 9
...concave groove, 10...water pipe, 11...lower jig, 12...upper jig, 12a...projection.

Claims (1)

[Claims] 1. A required number of concave grooves with a substantially U-shaped cross section shall be provided on the upper surface of the heat collecting plate whose upper surface is covered with a solar heat absorption film, and this heat collecting plate shall be placed above the bottom wall of the water heater case. Place the water pipes at specified intervals, insert the water pipes loosely into the grooves, place a lower jig with a flat top on the lower surface of the bottom wall of the water heater case, and place the lower surface on the top of the heat collecting plate. An upper jig that is flat and has a protrusion on its lower surface that abuts against the upper end of the water pipe in the concave groove to prevent the water pipe from rising, is provided so that the lower surface of the upper jig and the upper surface of the heat collecting plate are in close contact with each other, and The protrusions on the lower surface of the upper jig should be aligned so that they are in the groove, and the foam should be formed between the bottom wall of the water heater case and the heat collecting plate while the water pipe is being held down by the protrusions on the upper jig. A method for manufacturing a solar water heater, which comprises injecting and foaming a plastic heat insulating material, and deforming the groove wall by the foaming pressure so as to make it adhere to almost the entire circumference of a water pipe.