JPH0721392B2 - Heat transfer element - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heat transfer element capable of changing its shape relatively freely depending on a state of use.

[Prior Art] Conventionally, as a heat transfer element composed of a container in which a working fluid is sealed, a container made of almost a metal material is used.
Even when it is not in operation, it has a steam space (heat pipe and its application, Tetsuo Yamanishi and Sadaaki Shimizu, Ohmsha, 1980).

[Problems to be Solved by the Invention] However, although a metal material has advantages such as high thermal conductivity, it is basically a rigid body and can be deformed such as bent to some extent. It is fixed. Moreover, since it has a steam space at all times, it must have a large volume, which is a drawback when it is not needed.

The present invention has been made in view of the drawbacks of the related art, and an object of the present invention is to provide a heat transfer element that can be changed in shape to some extent according to a use state and has a small volume when not in use and is easy to handle.

[Means for Solving the Problems] The present invention relates to (1) a heat transfer element including a working fluid and a container for enclosing the working fluid, in which the container is filled with the working fluid when not in operation. And a volume of the container increases as the working fluid vaporizes during operation to form a gas space.

(2) The heat transfer element according to claim (1), wherein the container is a sheet-like material selected from a polymer film and a composite film of a polymer material and an inorganic material.

(3) The heat transfer element according to claim (1), characterized in that the container has a circulation passage formed on an inner surface thereof.

Here, the working fluid is a medium that transfers heat by phase change of vapor and condensation, and is a gas such as isopentane, pentane, methyl formate, methanol, acetone, ethanol, ethyl formate, and water at a temperature between 20 and 100 ° C. Any substance may be used as long as it has a point that causes a phase change of the liquid. The shape of the container is a flat tube as shown in FIGS. 1, 2 and 3, a state where two ends of two films are stuck, a form where one film is bent and one end is stuck, Any form may be used as long as it is easy to fill the working fluid when not in operation. For example, a sheet form can be made very thin and is suitable for the purpose of the present invention. Further, if there is a circulation passage such as a groove on the inner surface of the container, the working fluid is easily dispersed when not in operation, and the circulation of the working fluid during operation can be assisted. The constituent material of the container is generally a film made of a polymer resin such as polyolefin, polyamide and polyester, a composite film in which an inorganic substance such as a metal is vapor-deposited on the polymer film, and a composite (laminate) of polymers. , Coating, copolymerization, etc.) film, etc. A polymer film having a gas barrier property such as polyvinylidene chloride, polyvinyl alcohol or nylon is preferred. More preferably, in addition to the gas barrier properties described above, a film having good adhesion and heat sealing properties, for example, a film in which a polymer such as an ethylene-vinyl alcohol copolymer is composited (laminated or coated) is particularly preferable. Further, a container made of a material that expands like a balloon by vaporized gas or a material that captures only vaporized gas may be provided inside or outside the container under a structure capable of circulating.

In such a container, the amount of increase in the container volume during operation is preferably at least 30%, but particularly 100%
The above is desirable. Here, 100% is the volume increase when 0.5% of the total working fluid is vaporized.

[Operation] When heat is applied to a part of the heat transfer element in which the inside of the container is filled with the working fluid, the working fluid in the part absorbs heat and vaporizes to become working fluid vapor. At that time, a vapor space is formed. This vapor moves, is cooled from the outside, is liquefied, and then releases latent heat. The liquefied working fluid circulates to the heated portion, and this series of state changes is continuously performed to act as a heat transfer element. That is, when heat is not applied from the outside, a vapor space is not formed in the heat transfer element, and the space occupied by the heat transfer element is very small.

Example An example of the present invention is shown in FIG. A working fluid 2 is filled inside a container 1 made of an ethylene-vinyl alcohol copolymer film. In the heat transfer element constructed as described above, since the container is formed of a lightweight and flexible material, it is possible to change the shape relatively freely, and the steam can be changed when it is not in operation. Since no space is formed, the volume occupied by the heat transfer element when not in operation is very small as compared with the conventional heat transfer element that transfers heat by the same principle.

[Effects of the Invention] According to the present invention, it is possible to provide a heat transfer element having the following effects.

Since the inside of the container is filled with the working fluid, it can be heated from anywhere. That is, when a certain portion becomes the heat absorbing portion, the vicinity thereof always becomes the heat radiating portion.

It does not take up volume during storage and is easy to handle. For example, if it is a sheet of film, it can be rolled or folded and stored.

Since it can take a relatively free form, it can be used in a narrow space. That is, it is possible to secure heat absorption and heat dissipation areas without making the volume bulky.

Grooves formed on the inner surface of the container serve to recirculate the working fluid.

[Brief description of drawings]

1 to 3 show an example of the structure and form of the container of the present invention, FIG. 1 is a flat tube form, FIG. 2 is a state in which both ends of two films are bonded, and FIG. Is an example of a state in which one film is bent and one end is attached. FIG. 4 is a schematic view of the heat transfer element of the present invention.

Claims (3)

[Claims] 1. A heat transfer element comprising a working fluid and a container for enclosing the working fluid, wherein the container is filled with the working fluid when not in operation, and the working fluid is vaporized during operation. A heat transfer element, wherein the volume of the container is increased to form a gas space. 2. The heat transfer element according to claim 1, wherein the container is a sheet material selected from a polymer film and a composite film of a polymer material and an inorganic material. 3. The container according to claim 1, characterized in that a circulation passage is formed on an inner surface of the container.
The heat transfer element according to the item.