JPS5899689A - Sealing-in method for working fluid in heat pipe - Google Patents

Abstract

PURPOSE:To largely simplify a sealing-in operation of a working fluid, by a method wherein the evacuation of an interior space and injection of a working fluid are sequentially conducted by using a syringe needle pierced through a plug made of a highly elastic material. CONSTITUTION:The plug 4 made of a highly elastic material is press fitted to the open end side of a main body 1 of the heat pipe, and the syringe needle 5 is pierced through the plug 4 so that a tip hole 7 thereof reaches the interior space A of the main body 1. Then, an injector 10 for the working fluid is connected to the rear end of the needle 5 through a flexible pressure-resistant hose 9 or the like, and the atmosphere in the space A is replaced. After completing the replacement, the needle 5 is drawn out from the plug 4. At this time, the minute hole through which the needle 5 has been passed through the plug 4 is securely closed to maintain airtightness, since the plug 4 is made of the highly elastic material. Finally, the ends of the main body 1 are sealed in a perfectly airtight condition by screwed-type caps 2 or the like to complete the sealing-in process.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of enclosing a working fluid in a heat pipe easily and at low cost.

Currently, heat pipes have a wide range of uses, including in air conditioners and water heaters, melting snow on roads, and using waste heat in factories.

The most important process in the production of heat pipes is the working fluid, namely fluorocarbons and ammonia.

Some water is sealed inside the heat pipe body, and the following two methods are well known as methods for sealing this working fluid.

■ As shown in Figure 1, on the open end side of the heat pipe main body (1), one end of which has been previously closed, a steel pipe with a diameter of about 3 wMf (with a lid attached) is airtightly welded to the steel pipe ( 2/) is used to evacuate the internal space (A) of the main body, and then a working fluid is similarly injected from this steel pipe position/). Thereafter, the steel pipe (2/) is cut and temporarily closed by soldering, and a protective cap is screwed onto the end.

■ Same as above, one end of the pipe is closed (1)
At the open end of the adapter, as shown in FIG. Move the rubber plug (to) provided in 93 to the main body (1) side using the push rod (c) and fit it to make a temporary plug;
At this point, remove adapter 02 and attach the protective cap as described above.

However, all of these methods (■) require a lot of man-hours,
Higher costs cannot be avoided.

The present invention aims to provide a method for enclosing a working fluid in a heat pipe that eliminates such drawbacks. An injection needle is inserted into the stopper so that its tip hole reaches the internal space of the heat pipe main body, and the internal space of the main body is evacuated and the working fluid is injected sequentially through the injection needle, and then the injection is performed. The gist of the present invention is a method for enclosing a working fluid in a heat pipe, which is characterized by removing the needle and hermetically closing the end with a cap.

The method of the present invention will be explained in detail below based on the drawings.

≠ Figure 3 is an explanatory diagram showing the procedure for sealing a working fluid in a heat pipe based on the method of the present invention, and the present invention will be described in detail below with reference to the figure.

■ First (a) As shown in the figure, the Heat Buy 1 body (1)
Airtightly close one end of the tube with a screw-in cap, etc. At this time, the inner corner (3) of the open end of the pipe body (1) is preferably chamfered in advance to facilitate fitting of the plug (4'J, which will be described later).

■ Here, the plug for closing the open end of the main body (
Prepare 4 ri. It is necessary to use a highly elastic substance as the material for this stopper (4'l). Examples of highly elastic substances include hard rubber, soft rubber, and polymer compounds such as polyurethane, acrylonitrile, and fluorocarbon resin. .

The shape of the stopper (lll) may be a simple flat cylindrical shape as shown in the cut section, but it is preferable to have a shape tapered at the tip side as shown in Figure 1 (A), as this will facilitate insertion as described below. Furthermore, when the material is hard, such as hard rubber, the injection needle insertion point (f' ) should be shaped so that the thickness <S> of the heat pipe body (1) is small.Also, considering the sealing performance with the inner surface of the heat pipe body (1),
If it is made of hard rubber, it is recommended to cover the surface with soft rubber. If the material is soft, such as soft rubber,
It is also effective to take measures such as incorporating a reinforcing ring (6) to increase the rigidity, as shown in (A) (cross-sectional view) and (B) (plan view) in Figure (C). A stopper like this (4
The outer diameter (D/) of the IJ is determined in consideration of the inner diameter (D) of the main body (1) of the heat pie 1 so that it can be tightly fitted into the main body (1).

■ This stopper (lIJ) is press-fitted into the open end side of the heat pipe main body (1) with one end closed as shown in figure (c), and the injection needle (j) is inserted into this stopper (lll) through its tip hole (
7) is inserted so that it reaches the internal space (A) of the main body. The thickness of the injection needle (5) should be as thin as possible, but it is also desirable to have a diameter of 3M or less, considering workability. If you use one that is too thick, there is a risk that a hole will form in the stopper (lIl) after it is removed, impairing its function as a stopper. However, it is more advantageous to insert the injection needle T51 into the state shown in Fig. (B) and then press fit it into the heat pipe body (1). ), it is best to use a valve (with gJ).

(2) Next, connect a working fluid injection device (/4) to the rear end of the injection needle TS via a connectable pressure hose (91 or the like).This device may have the same structure as that used conventionally. Briefly, the supply pipe 4 is provided with a supply source (lIl) of a working fluid, such as fluorocarbon, and the supply pipe 4 is connected to the injection needle (5).
Connect to. This supply pipe V2 has a valve V! , a pressure gauge (/L supply amount measuring device f75 is attached. At the same time, a vacuum pump V4 is provided, and its intake pipe V7
is connected to the downstream side of the auxiliary equipment of the supply pipe V2, and this intake pipe (/7) is provided with a valve and a vacuum gauge (c).

Here, using the working fluid injection device (/4) as described above,
The atmosphere in the internal space (A) of the pipe body (1) is replaced by the following procedure. First, open the injection needle (5+ valve (g+), close the injection side valve V3, open the intake side valve (device), and start the operation of the vacuum pump (/4). Check the degree of vacuum in the internal space (A) of the main body, and when the value reaches a predetermined value, close the valve on the intake side. After this vacuum, continue to close the valve on the injection side. Open V3 to activate the supply source (l/) and send in force fluid.The amount to be injected into the internal space (A) of the main body is known from the display on the metering device (5), and that value is the amount to be sealed. The supply is continued until the pulp is reached, and then the pulp V3 is closed.

■ After closing the pulp (εj) of the injection needle (S), remove the injection device 4, and then plug the injection needle (5) (
Remove from lIl (see figure). At this time, stopper (4
The pore through which the injection needle (S) in step t) was inserted is reliably sealed and sealed because the stopper is made of a highly elastic material as described above.
It is closed and kept airtight. After the end is temporarily closed in this manner, the end is closed completely airtight using a screw-in cap (:ll, etc.) in the same way as the previously closed end, and the sealing operation is completed.

According to the method of the present invention described above, there is no need to use welding or special adapters for temporary closing when the working fluid is sealed, and the sealing work is greatly simplified, thereby reducing the work cost. This will result in a significant reduction in Moreover, the method of the present invention has great advantages in its practical application, such as the fact that it can be expected to have extremely high reliability of work.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams showing a conventional method of enclosing a working fluid in a heat vibrator, and FIG. 3 is a diagram illustrating the working procedure of enclosing the working fluid based on the method of the present invention. (→ and (c) are diagrams showing structural examples of temporary closure plugs used in the method of the present invention. In the diagrams, l: main body of heat-by 1, 2: cap, 3: inner corner of open end, ≠ : stopper, j: injection needle, t: reinforcement ring,
7: tip hole, r: pulp, ri: pressure resistant hose, lO: working fluid injection device, ll: working fluid supply device, 12 knee supply pipe, 13: pulp, li: pressure gauge, lj 2 meter, 16
: Vacuum pump, 17: Intake pipe, try pulp, L: Vacuum gauge, 20: Lid, 21: Steel pipe, 22 Near adapter, Co3
: Through hole, 2v: Rubber stopper, C: Push rod No. 3 (A) Fig. 1

Claims (1)

[Claims] (1) A stopper made of a highly elastic material such as rubber is tightly fitted into the open end side of the beat pipe main body with one end closed, and an injection needle is inserted into the stopper so that its tip hole reaches the internal space of the heat-by 1 main body. A heat pipe characterized in that the inner space is evacuated and the working fluid is injected sequentially through the injection needle, and then the injection needle is removed and the end is hermetically closed with a cap. Method of enclosing operating fluid.