JPS6340648B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to, for example, a method for manufacturing a thermal water tank in which hot water is stored by surrounding the tank with a heat insulating material. The molded inner tank and the exterior wall can be easily integrated using foamed heat insulating material.

The present invention will be explained below according to an example applied to a thermal water tank of a solar heat collector.
The inner tank is constructed as a watertight container using synthetic resin material such as polyethylene, and has through holes 2 and 2' in the side wall 3 for the insertion of a water inlet, a hot water outlet, or a heating pipe.
There is also an opening 4 in the top 5 for internal cleaning or piping installation services. Reference numeral 6 denotes an exterior wall made of polypropylene, for example, which has an opening formed in such a way that a surface 8 that fits into the opening flange 7 at the top of the inner tank 1 is formed on the periphery; This is a foamed heat insulating material that fills the space between them to integrate them and surrounds the outer periphery of the inner tank 1 as a heat insulating wall.

Such a heated water tank can be manufactured extremely easily by fitting the inner tank 1 into the exterior wall 6 and injecting the foamed heat insulating material 9 between the inner tank 1 and the exterior wall 6. Since both the inner tank 1 and the outer wall 6 are made of synthetic resin, if the inside of the inner tank 1 and the outside of the outer wall 6 are not pressed and held together with a suitable core or molded material, the pressure during foaming of the insulation material will increase. Plastic deformation may occur due to reaction heat. When the opening 4 of the thermal water tank is large, a core or mold material can be inserted through the opening 4 during such insulation foaming to prevent plastic deformation of the inner tank during foaming, but as shown in Figure 1, In tanks where only a small opening can be formed, it is difficult to use jigs or cores to reinforce the inner tank, and the deformation that occurs in the inner tank due to the reaction heat and pressure during foaming, as mentioned above, is almost impossible in practical use. is intolerable,
In particular, at present it has not been put to practical use in tanks, etc., which require secondary processing to form through holes in the side walls.

The present invention, which was made in view of these points, has an inner tank 1.
For example, a heat-retaining water tank is manufactured by directly using a molded product blow-molded from a synthetic resin such as polyethylene, and will be described below with reference to FIG. The figure shows the state before injection of the heat insulating material 9. After blow molding the inner tank 1, molding burrs have been removed so as not to damage the thin films for mounting the individual parts, and the air inlet 10 during blow molding has been removed. Using this method, air is injected into the inner tank 1, and the air inlet 10 is sealed with a sealing plug 11 while applying internal pressure.

This internal pressure varies depending on the size of the inner tank 1 and the type of foam insulation material described later, but even if heated and pressurized during the foam insulation treatment process, the inner tank 1 may undergo abnormal inward plastic deformation. For example, the internal pressure (0.01 to 0.5
Kg/cm ³ ).

The inner tank 1 to which internal pressure has been applied in this way, the exterior wall 6, the reinforcing metal fittings 12 (or bottom plate) of the thermal water tank, and the spacer 1 for secondary processing of the hole described later
5 is assembled into the foaming jig 13, 13', and a foamed insulation material such as hard foamed urethane is injected from the injection port 14 between the inner tank 1 and the exterior wall 6 and solidified. ) is integrated with the exterior wall 6 and the bottom plate 12, and the jigs 13, 1
It is taken out from 3'.

After such heat insulating foaming treatment, the air inlet 10 to which the internal pressure was previously applied is removed, or the top opening 4 is formed, and the holes 2, 2' for inserting the water inlet, the tap water outlet, or the heating pipe are formed.
By performing secondary processing such as perforation, a heated water tank as shown in FIG. 1 can be completed.

The exterior wall 6 may be made of sheet metal or a molded product using various manufacturing methods using synthetic resin materials. If a special jig is used, it may be necessary to foam the insulation material integrally with the inner tank 1. Alternatively, an exterior wall may be formed by attaching a weather-resistant thin film or forming a film on the surface of the heat insulating material.

As described above, the method for manufacturing a thermal water tank according to the present invention involves integrating the foam insulation material with the exterior wall while applying internal pressure to the pre-formed synthetic resin inner tank. This eliminates complicated processing steps such as inserting molds and inserting split molds, reduces the defective rate, and enables efficient supply of inexpensive warm water tanks.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a thermal water tank manufactured according to the present invention, and FIG. 2 is a sectional view illustrating one manufacturing step. 1...Inner tank, 6...Exterior wall, 9...Foam insulation material, 10...Air inlet.

Claims (1)

[Claims] 1 A synthetic resin inner tank filled with pressurized gas is fitted into the exterior wall, and a foamed heat insulating material is injected between the exterior wall and the inner tank to which internal pressure is applied, and the foam is solidified to form the exterior. A method for manufacturing a thermal water tank in which the wall and the inner tank are integrated, and then pressurized gas is discharged and secondary processing is performed.