JPS594897A - Heat exchanger - Google Patents

Abstract

PURPOSE:To improve the heat transfer efficiency by forming a heat transfer pipe of a heat exchanger with a plastics pipe, on inside surface thereof a hydrophilic layer is formed. CONSTITUTION:A polyester film tape 1 having a thickness less than 0.1mm. is slantingly and endlessly wound as overlapping one portion of the tape, and the overlapped portion is welded with a thermosetting polyester family adhensive, then a cylindrical pipe 2 is formed. The pipe 2 formed by said process is cut at a required dimension, inserted into a side plate 4 made of plastics which is provided with through holes 3 in equal interval, then adhered with said side plate 4, thus, a heat exchanger is structured. A contact angle between the pipe 2 and the water is 65-70 deg. in forward contact angle, 48-50 deg. in backward contact angle. A hydrophilic layer 5 is formed by the corona discharge treatment, or by coating of such hydrophilic agent as a water glass and the like. Consequently, the water drops 6 adhered on the inside wall of the pipe 2 becomes especially small, accordingly, the moistue condensation effect is improved, the heat exchange efficiency is also improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a heat exchanger used for dehumidification and heat exchange in equipment such as clothes dryers and air conditioners.

Conventional configuration and its problems In conventional equipment such as clothes dryers, heat exchangers are equipped with radiating fins made of thin aluminum plates around copper pipes in order to dehumidify high-temperature, humid air and exchange heat. was using.

However, such a heat exchanger using a copper pipe has a drawback that the heat transfer area on the inner diameter side is small and the heat exchange efficiency is poor.

In addition, if you increase the number of copper pipes to increase the heat transfer area on the inner diameter side, that is, on the high temperature side, the amount of copper pipes used will increase, resulting in higher costs, and the shape will also become larger, saving resources. However, there was a problem that energy saving could not be achieved.

Also, looking at the state of dew condensation inside the pipe, as shown in Fig.
The water droplets 8 act as air pockets and have a heat insulating effect, and the water droplets 8 have a thickness in the direction perpendicular to the flow and have a heat insulating effect.As a result, the heat exchange effect and dew condensation performance are reduced.

OBJECTS OF THE INVENTION The present invention provides a heat exchanger that can improve the heat conduction efficiency by increasing the heat conduction area on the high temperature side without increasing the cost and can also be lightweight. , the pressure difference between the high temperature side and the low temperature side is relatively small, for example, the water column pressure is 0.
It is suitable for clothes dryers, air conditioners, etc. that use heat exchangers with ~100 questions.

Structure of the Invention The heat conduction pipe of the heat exchanger is constructed of a plastic pipe with a hydrophilic layer formed on the inner surface.

DESCRIPTION OF THE EMBODIMENTS A polyester film tape 1 having a thickness of 0.01 mm or less is wound diagonally endlessly as shown in FIG. to form a cylindrical pipe 2. The overlapped part is
Since the strength of the pipe 20 is increased and the other parts are formed of a thin film, the heat exchange efficiency is improved.

The pipe 2 obtained in this way is cut into the required dimensions,
As shown in Figures 3 and 4, if a heat exchanger is constructed by inserting and gluing a side plate 4 made of Planutix with through holes 3 at equal intervals, the cost will be high even if the heat conduction area on the high temperature side is large. The number of shivives can be increased by 3 to 4 times compared to conventional methods, and it shows good effects when the temperature on the high temperature side is about 100℃ or less and the pressure difference on the low temperature side is small. .

The contact angle between the pipe 2 and water is an advancing contact angle of 65 to 700.
．． The receding contact angle is 48 to 6σ, and a hydrophilic layer is formed on the inner surface by corona discharge treatment or by coating with a hydrophilic agent such as water glass. In addition, the following hydrophilic treatment is also effective in forming a layer to maintain hydrophilicity.

Epoxy resin 2-16%, preferably 8%, calcium hydroxide powder O 12-6%, preferably 1%, solvent 79-6%
97.8%, preferably 91%, is mixed to form a layer 6 of about 1-3μ on the inner wall of the pipe 2.

As a result, the water droplets 6 adhering to the inner wall of the pipe 2 become extremely small, improving the dew condensation effect, and furthermore, no air pockets are formed, improving the heat exchange efficiency.

Effects of the Invention The present invention improves heat conduction efficiency by constructing a heat conduction pipe of a heat exchanger using a plastic pipe having a hydrophilic layer formed on its inner surface.

[Brief explanation of drawings]

Figure 1 is a cross-sectional explanatory diagram of a conventional heat conduction pipe, Figure 2
3 is a perspective view of a heat exchange element using the same pipe, FIG. 4 is a sectional view of the heat exchange element, and FIG. It is a cross-sectional explanatory view of a heat conduction pipe. 2... Pipe, 6... Hydrophilic winding layer. Name of agent: Patent attorney Toshio Nakao and 1 other person-4
Shimi faction Taki faction faction 1'-453-

Claims (1)

[Claims] A heat exchanger consisting of a heat conduction pipe made of planutic spide with a hydrophilic layer formed on its inner surface.