JPH03146232A - End treatment of grooved pipe material - Google Patents

Abstract

PURPOSE:To highly reduce the diameter of the end of a grooved pipe material by drawing the end of the pipe material by using a forming roll which is provided loosely rotatable on the surface of a rotating mechanism rotating at a high speed and movably diametrally on the surface of the rotating mechanism. CONSTITUTION:The end treating device 2 is provided with the forming roll 4 which is provided loosely rotatable on the surface of the rotating mechanism 3 rotating at a high speed and movably diametrally on the surface of the rotating mechanism 3 at the time of drawing the front end of the grooved pipe material 1 formed with inside surface grooves in the longitudinal direction like the grooved pipe material 1'. The forming roll 4 is designed to continuously press only one end at the front end of the pipe material 1 and can increase the deformation rate of the pipe material 1. The treating of the end to the extremely small end by the drawing is possible in this way.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to refrigerant channels and heat pipes of heat exchangers such as refrigerators, automobile air conditioners, general building air conditioners, store showcases, etc. The present invention relates to a method for treating the end of a grooved pipe material.

(Prior Art) Conventionally, a refrigerant flow path or a heat vibrator of a heat exchanger may use a grooved tube material having grooves formed on the inner surface in order to improve the heat exchange efficiency to the tube material.

Various types of heat exchange media are used to enclose and circulate inside the grooved pipe material mentioned above, depending on the purpose, and in some cases, a highly volatile heat exchange medium is used. High airtightness and liquidtightness are also required at the ends after the heat exchange medium is filled inside.

Conventionally, the ends of grooved pipe materials as described above cannot be drawn to a diameter that can be welded with a press like normal pipe materials that do not have grooves on the inner surface. The method used was to seal it by covering it with wood.

The conventional method for treating the ends of the grooved tube material described above is to first semi-draw the tube material using a press, then weld a lid material having a thin tube to the end of the tube material, and connect a nozzle to the thin tube. After filling the heat exchange medium, the tube was cut and the cut surfaces of the tube were welded.

<Problems to be Solved by the Invention> However, the method described above requires a large number of steps, making the work complicated, and requires a lid material, resulting in high production costs.

Furthermore, because the diameter of the end of the grooved pipe cannot be sufficiently reduced by drawing with a press, welding the end of the pipe and the lid part is extremely troublesome, and there is a risk of a decrease in the pressure resistance of the welded part and weld leakage. there were.

<Means for Solving the Problems> The present invention has been proposed in view of the above, and includes forming a molded part recessed in an arc shape between the large diameter part at the base end and the small diameter part at the distal end on the surface of the rotating mechanism. The forming roll is provided so as to be freely rotatable and movable in the radial direction of the rotating mechanism, and the rotating mechanism is rotated with the tip portion of a grooved tube material having grooves formed in the inner surface in the length direction facing the forming roll. The drawing process is performed so that the diameter of the tip portion of the grooved pipe material is reduced based on the rotation of the rotation mechanism (revolution and idle rotation of the forming roll, and movement of the forming roll in the radial direction). The present invention relates to a method for treating the end of a grooved tube.

<Example> Examples of the present invention will be described in detail below based on the drawings.

The method for treating the end of a grooved tube according to the present invention is to sufficiently reduce the diameter of the tip of a grooved tube 1 having grooves formed in the length direction on the inner surface as shown in FIG. 1, as shown in FIG. The grooved pipe material is drawn to a diameter of 1°.

As shown in FIG. 3, the edge processing device 2 used in the present invention has a forming roll 4 placed on the surface of a rotating mechanism 3 that rotates at high speed so that it can freely rotate and move in the radial direction of the rotating mechanism 3. It was established.

The above-mentioned forming roll 4 has an arch-shaped forming part 7 formed between a large diameter part 5 at the base end and a small diameter part 6 at the tip, and rotates freely on the surface of the rotating mechanism 3 and rotates. Mechanism 3
It has a support axis parallel to the rotation axis of.

The forming roll 4 described above can be moved in the radial direction of the rotation mechanism 3 by, for example, a cylinder mechanism (not shown).

In order to draw the tip of the tube material 1 using the end treatment device 2 as described above, first, the tube material 1 is positioned at the center of the rotating mechanism 3, and the tip portion of the tube material 1 is positioned so as to face the forming roll 4. It is fixed by a fixing means 8 such as a clamp.

Next, the rotating mechanism 3 is rotated at high speed by an appropriate drive device (not shown) to cause the forming roll 4 to revolve based on the rotation of the rotating mechanism 3, and the forming roll 4 comes into contact with the tip portion of the tube material 1. (arrow in Figure 3).

Then, the outer surface of the forming roll 4 is always kept in contact with the tip end of the tube material 1, and the forming roll 4 is moved in the radial direction toward the center of the rotation mechanism 3, so that the tip end of the tube material 1 is gradually moved. If pressed firmly, the diameter can be reduced sufficiently.

Therefore, the pipe material l whose diameter is reduced by the method of the present invention described above.
The tip end portion of is squeezed into a shape that matches the arc-shaped forming portion 7 of the forming roll 4.

In the present invention described above, the forming roll 4 is one that continuously presses only a part of the tip portion of the tube material 1; for example, the forming roll 4 presses the entire periphery of the tip portion of the tube material 1 at the same time, as in conventional drawing processing. Therefore, the deformation rate of the tube material 1 can be increased, and it is possible to process even the end portion with an extremely small diameter compared to conventional drawing processing.

In addition, since the forming roll 4 pressed against the tube material 1 freely rotates, the resistance can be minimized and generation of frictional heat can be suppressed. By adjusting the moving speed, uniform drawing can be performed, and the surface condition of the drawn tip becomes extremely beautiful.

The grooved tube l whose diameter has been reduced according to the present invention described above can be filled with a heat exchange medium through the reduced diameter small open end, and this open end can be closed by welding or the like to be used as a cooling channel or heat pipe. Can be done.

Therefore, when the present invention is applied to the production of cooling channels for heat exchangers or heat vibrators, the number of steps can be reduced compared to the conventional processing method described above, and since the diameter of the opening end is small, Welding work can be easily performed, and the pressure resistance of the welded portion and the risk of weld leakage can be eliminated.

<Effects of the Invention> As explained above, according to the method for treating the end of a grooved tube according to the present invention, it is possible to easily draw a grooved tube to an extremely small diameter, which is almost impossible with conventional drawing. can do.

Further, the present invention can suppress heat generation during processing, and can perform drawing processing with a smooth surface and uniformity.

Furthermore, the edge treatment method of the present invention can be easily assembled as a device with a simple configuration, and can be automated to provide further practicality.

Therefore, the grooved tube material reduced in diameter according to the present invention reduces the number of work steps in the production of cooling channels of heat exchangers or heat vibrators, and facilitates welding with pressure resistance and no risk of weld leakage. It can be easily formed.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view of a grooved tube material before implementing the present invention, FIG. 2 is a perspective view of a grooved tube material after implementing the present invention, and FIG. 3 is a schematic side view of the end processing device, and FIG. 4 is a front view of the same. (Explanation of symbols) 1 is a grooved tube material, 3 is a rotating mechanism, 4 is a forming roll, 5 is a large diameter portion, 6 is a small diameter portion, and 7 is a forming portion.

Claims (1)

[Claims] A forming roll having an arcuate concave forming portion formed between a large diameter portion at the base end and a small diameter portion at the distal end is provided on the surface of the rotating mechanism so as to be freely rotatable and movable in the radial direction of the rotating mechanism, The rotary mechanism is rotated with the tip of the grooved tube material having grooves formed in the length direction on the inner surface facing the forming roll, and the forming roll revolves and idles based on the rotation of the rotating mechanism, and the forming roll is rotated in the radial direction. 1. A method for treating an end of a grooved pipe material, characterized in that the end portion of the grooved pipe material is drawn so as to reduce its diameter by the movement of the grooved pipe material.