CN2460927Y - Vacuum pipe for solar heat collector - Google Patents

Abstract

The utility model relates to a large caliber straight-way type vacuum pipe for a solar heat collecting device. The utility model belongs to a solar energy utilization device and is composed of an inner layer glass pipe and an outer layer glass pipe which are sheathed together. A selective coating is coated on the wall surface of the inner pipe. The ends of the two pipes are sealed and connected, forming a closed cavity which is evacuated into vacuum. The inner pipe is a corrugated expansion pipe or a corrugated expansion joint is only made at one end of the inner pipe. The thermal expansion stress difference of inner and outer glass can be effectively reduced. The large caliber straight-way type vacuum pipe for a solar heat collecting device can be utilized for a long time and can not be easily broken under the condition of a great temperature difference.

Description

A kind of solar thermal collector vacuum tube

The utility model relates to a kind of solar thermal collector vacuum tube, belongs to solar thermal utilization equipment.

In solar energy heat utilization device, solar water heating system is to use the most general a kind of form, and the raising of solar water heating system efficiency of utilization is people's questions of common concern, improves the hot water temperature and is even more important.The heat collector vacuum tube of many solar water heaters is that the double layer vacuum tube with an end closure directly inserts in the water tank and fixing, the inner tubal wall face is coated with selective coating, the hot and cold water circulation is all carried out in the same space in pipe, the little degree of depth of a pipe bore is big, the thermal cycle difficulty, Heat-collecting effect is poor, efficiency of utilization is lower, and owing to the temperature of inner and outer pipes differs, the expanded by heating elongation is also different, so two pipe joints are easy to break, for this reason, the Chinese patent communique disclosed a kind of through vacuum nested solar heat-collecting tube (CN1191295A) on August 26th, 1998, and it is the set metal pipe in double-layer glass tube, and the metal tube wall is coated with selective coating, connect with silicon rubber loop between glass tube and the metal tube, form through vacuum nested solar heat-collecting tube, but this kind pipe is owing to be to make complex structure with two kinds of materials, cost is higher, and the design of heat collector is also complicated.

The purpose of this utility model, just providing a kind of inner and outer pipes Yin Wendu that can effectively eliminate differs, the shortcoming that the expanded by heating elongation is different, joint is easy to break, simple in structure again, the solar thermal collector vacuum tube of the design of simplification heat collector, raising efficiency of utilization.

For achieving the above object, solar thermal collector vacuum tube of the present utility model is made of the internal and external layers of glass pipe that is nested together, the inner tubal wall face is coated with selective coating, and the end sealing-in of two pipes forms a sealed hollow, in the middle of be evacuated, it is characterized in that: interior pipe is a corrugated expansion pipe.

On above-mentioned basis, also can make another kind of form: pipe is only at one end made expansion bellow in described.

After having taked above-mentioned technological facilities, solar thermal collector vacuum tube of the present utility model, make simple, and because interior pipe is a corrugated expansion pipe, when inner and outer pipes since the axial elongation that temperature differs, expanded by heating difference, interior pipe produce during greater than outer tube in pipe the leeway of elongation is arranged, do not cause the damage of breaking of the end of two pipes.

Further describe in detail below in conjunction with drawings and Examples.

Fig. 1 is the structural profile schematic diagram of first kind of embodiment of the present utility model.

Fig. 2 is the structural profile schematic diagram of second kind of embodiment of the present utility model.

From Fig. 1, can see, first kind of embodiment of solar thermal collector vacuum tube of the present utility model, constitute by the inside and outside layer glass tube 1,2 that is nested together, the inner tubal wall face is coated with selective coating 3, the end sealing-in of two pipes, form a sealed hollow 4, in the middle of be evacuated, the section vertically of interior pipe 2 is the expansion bellow shape; The structure of second kind of embodiment of Fig. 2 is also basic identical, and just interior pipe is only at one end made expansion bellow.

So work as inner and outer pipes because temperature differs, expanded by heating difference, the axial elongation that interior pipe produces during greater than outer tube in the expansion bellow of pipe as the convergent-divergent pipe, the leeway of elongation is arranged, the axial thermal stress that can regulate inner and outer pipes automatically is poor, does not cause the damage of breaking of the end of two pipes.

Heavy caliber straight-through vacuum tube of the present utility model can be directly used in solar thermal collector; Also can insert through type metal fin pipe, form solar thermal collector, solar thermal collection system Have the characteristics such as efficient, simple, non-scaling obstruction.

Claims (2)

1, a kind of solar thermal collector vacuum tube, constitute by the inside and outside layer glass tube (1,2) that is nested together, interior pipe (1) wall is coated with selective coating (3), the end sealing-in of two pipes, form a sealed hollow (4), in the middle of be evacuated, it is characterized in that: pipe (1) is for the expansion bellow pipe in described.

2, according to the solar thermal collector vacuum tube of claim 1, it is characterized in that: pipe (1) is only at one end made expansion bellow in described.

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