JPH0612371Y2 - heat pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field This invention relates to a heat pipe for transporting heat as latent heat of vaporization of a fluid enclosed in a sealed tube.

As is well known in the prior art, the basic structure of a heat pipe is water that completely exhausts non-condensable gas such as air from the inside of a sealed tube made of metal tube, and evaporates and condenses into liquid at the intended temperature. A condensable fluid such as ammonia or ammonia is enclosed in the closed tube as a working fluid, and a wick that causes a capillary pressure is provided inside the closed tube in order to recirculate the liquid-phase working fluid to the place where evaporation occurs. This is the configuration provided.
Therefore, if one end of the heat pipe is heated and the other end is cooled, the working fluid evaporates due to heat input from the outside and the vapor pressure at that location increases, whereas at the location where it is cooled, the working fluid Radiates heat to condense and liquefy, so that the vapor pressure at that location becomes low, and as a result, the working fluid vapor flows from the heating portion to the cooling portion, and heat is transported as latent heat of vaporization. Also, in the heating part, the working fluid evaporates to lower the liquid level in the wick and lower the liquid pressure, whereas in the cooling part, the working fluid condenses and liquefies, resulting in a higher liquid pressure. The working fluid of the phase returns from the cooling section to the heating section through the wick.

However, in the heat pipe, if there is a temperature difference between the two parts, the part with the higher temperature becomes the heat input part and the working fluid evaporates, and the part with the lower temperature becomes the heat dissipation part. As the working fluid condenses, heat transfer between two locations separated from each other with the entire heat pipe exposed to the specified atmosphere will result in an unexpected temperature of the heat pipe being affected by the ambient temperature. Part and heat input part. In such a case, the working fluid may condense or evaporate in the unexpected heat radiating part or heat input part, so that the heat is not transferred to the intended location, or the working fluid in the liquid phase is the original heat input part. There is a problem in that the heat transport capacity is lowered because of insufficient reflux.

The present invention has been made in view of the above circumstances, and provides a heat pipe capable of reliably and sufficiently transferring heat between an initial heat input portion and a heat radiating portion, particularly a heat pipe using a corrugated pipe. The purpose is to do.

Means for Solving the Problems In order to achieve the above object, the present invention uses a corrugated pipe as a closed pipe which is a main body of a heat pipe,
A heat insulating material is attached to the outer periphery of the corrugated pipe between the heat input portion and the heat radiation portion so that an air layer is left on the outer periphery of the small diameter portion (recess) of the corrugated pipe. It is characterized in that a heat insulating layer is formed.

Action In the heat pipe of the present invention, the working fluid in the closed pipe evaporates in the heat input part and the vapor flows to the heat radiating part to condense, but between the heat input part and the heat radiating part to the outside. Since it is insulated, the working fluid does not evaporate or condense in that portion, and therefore almost all of the heat given to the heat input portion is transported to the heat radiating portion. Since the corrugated pipe is used as the closed pipe, the heat pipe as a whole has flexibility. Moreover, the heat insulating layer is formed by effectively utilizing the unevenness on the outer circumference of the corrugated pipe, and by attaching the heat insulating material so as to leave an air layer on the outer circumference of the small diameter portion (recess) of the outer circumference of the corrugated pipe. Both the air layer and the heat insulating material exert a heat insulating function.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing an embodiment of the present invention. In the example shown here, each end of a closed tube 1 made of a metal corrugated tube is connected to a heat input section 2 and a heat radiation section 3, respectively. It is what That is, inside the closed tube 1, substantially,
Only condensable working fluid such as water is enclosed,
A wick 4 for generating a capillary pressure for refluxing a liquid-phase working fluid is provided inside the sealed tube 1. A heat insulating layer 5 is formed on the outer peripheral side of the closed tube 1 between the heat input section 2 and the heat radiation section 3. This heat insulating layer 5 is for preventing heat conduction between the inside and the outside of the closed tube 1, and is a cylindrical heat insulating material having low heat conductivity such as synthetic resin such as polyethylene or polyvinyl chloride, rubber, or ceramic. It is formed by fitting the material 6 on the outer circumference of the closed pipe (corrugated pipe) 1. That is, the air layer 12 is left between the outer peripheral side of the small-diameter portion (recess) of the corrugated pipe 1 and the inner surface of the cylindrical heat insulating material 6, and therefore the heat insulating layer 5 is the heat insulating material 6 and the air layer. 12 and 12.

Also in the heat pipe shown in FIG. 1, the working fluid is evaporated by the heat Q given to the heat input section 2, and the vapor is radiated by the heat radiating section 3
The heat Q is discharged and the heat is condensed to perform heat transfer as latent heat of vaporization of the working fluid. Further, the liquid-phase working fluid passes through the inside of the wick 4 and returns to the heat input section 2.

In the place where the heat insulating layer 5 is provided while the working fluid evaporates and condenses and thus circulates and flows,
Since heat exchange with the outside is blocked, evaporation or condensation of the working fluid does not occur, and therefore almost the entire amount of heat input is taken up by the heat radiating portion 3.
And the liquid-phase working fluid is sufficiently refluxed to the heat input section 2.

As described above, according to the heat pipe of this invention,
Since the heat insulating layer is provided between the heat input section and the heat radiation section, evaporation or condensation of the working fluid occurs only in the heat input section and the heat radiation section, and therefore almost all of the heat given to the heat input section is transferred to the heat radiation section. In addition to being carried, the liquid-phase working fluid is sufficiently refluxed to the heat input section, and as a result, a heat pipe with good thermal efficiency can be obtained. Further, in the heat pipe of the present invention, since the closed pipe is constituted by the corrugated pipe, not only it has flexibility as a whole, but especially the heat insulating layer between the heat input part and the heat radiation part is Since the heat insulating material is attached to the outer circumference of the small diameter portion (recess) so that an air layer is left, the heat insulating function of that portion is exhibited by both the air layer and the heat insulating material, and the heat insulating material itself is inexpensive. In addition, it is easy to attach, and therefore, there is an effect that excellent heat insulation can be provided between the heat input portion and the heat radiation portion with a simple and inexpensive structure.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention. 1 ... Closed pipe (corrugated pipe), 2 ... Heat input part, 3 ...
Heat dissipation part, 5 ... Insulating layer, 6 ... Insulating material, 12 ... Air layer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Michio Takaoka 5-1-5 Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (72) Tsuneaki Madawa 1-1-5, Kiba, Koto-ku, Tokyo Fujikura Electric wire company (56) Reference JP-A-56-30587 (JP, A) JP-B-58-19014 (JP, B1)

Claims (1)

[Scope of utility model registration request] 1. A sealed tube is filled with only a substantially condensable fluid as a working fluid, and a part of the sealed tube is used as a heat input section for giving heat from the outside, and the other part of the sealed tube is In a heat pipe as a heat radiating section that takes away heat, the closed tube is a corrugated tube, and on the outer peripheral side between the heat input section and the heat radiating section of the corrugated tube, on the outer periphery of the small diameter part of the corrugated tube. A heat pipe having a heat insulating layer formed by attaching a heat insulating material so as to leave an air layer.