JPS58167029A - Method and apparatus for continuous manufacture of pipe having internal spiral groove - Google Patents

Abstract

PURPOSE:To manufacture a long-sized pipe having internal spiral groove continuously from a pipe having internal linear groove, by giving twisting action only to the part of the pipe between holding rollers provided between a rewinding drum and a winding drum. CONSTITUTION:A pipe 3A having internal linear groove is wound from a rewinding drum attached to a rotary frame 1 for pipe twisting, and hole between a pair of holding rolls 5, 5 attached to the front end of the frame 1. If is then wound on a front winding drum 6 of a capstan 44. It is introduced into a rear winding drum 7 and taken up on a winding drum 8 of a winch 45. With rotation of the rotary frame 1, twisting of the pipe 3A is generated from the starting point of winding of the front winding drum to the pipe sending-out point of the roller 5, and not generated in the part between the drum 4 and roller 5. Accordingly, rewinding of the pipe 3A by the drum 4 is carried out smoothly, and a long-sized pipe having internal spiral groove can be manufactured continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously manufacturing internally spiral grooved tubes mainly used as refrigerant tubes of heat exchangers, and an apparatus for carrying out this method.

When inner spiral grooved tubes are used for refrigerant tubes, the heat exchange efficiency between the circulating refrigerant inside the tubes and the air outside the tubes is greater than that of straight tubes, which is advantageous for downsizing heat exchangers and saving materials. It is. By the way, in order to manufacture such internally spiral grooved tubes, conventionally a grooved tool is inserted into the tube and rotated during tube drawing, or a mandrel having a grooved portion is rotated during tube expansion. However, since both the former grooved tool and the latter mandrel have shafts,
Since there is a limit to the length of this shaft, it has been impossible to manufacture a long tube with internal spiral grooves. There is also a proposal to use a spiral grooved die to form internal spiral grooves during extrusion molding of tubes, but this method is still not practical due to high mold costs and manufacturing conditions constraints. has not yet been achieved.

The object of this invention is to provide a method for manufacturing a long internally spiral grooved tube in a practical and continuous manner, and one of the objects of this invention is to provide
A straight inner grooved pipe is extruded, the inner straight grooved pipe is wound onto an unwinding drum attached to a rotating frame for twisting the pipe, and the inner straight groove is wound up from the unwinding drum while rotating the rotating frame for twisting the pipe. The grooved tube is passed through a pair of clamping rollers attached to the front end of the tube twisting rotation frame and unwound as it is to the clamping rollers, and the rewound tube is wrapped around the tube placed in front of the tube twisting rotation frame. Wrap it around the drum, and place the pinching roller and the winding between the drums. As the rotating frame rotates, the tube is twisted, transforming the straight groove into a helical groove, and the inner straight grooved tube is continuously turned into an inner spiral groove. A continuous method for manufacturing an internally spiral grooved tube characterized by converting it into a grooved tube, and another aspect of this invention is an invention of an apparatus directly used for carrying out the method invention, comprising: This device consists of a rotating frame for twisting a pipe, an unwinding drum that is attached to the rotating frame and that unwinds the tube with an inner straight groove, and a pair of unwinding drums that are attached to the front end of the rotating frame and sandwich the tube that is being rewound. The wrapping method is similar to that of a drum, in which the inner spiral grooved tube, which is arranged in the opposite direction of the rotating frame and whose linear grooves are twisted into spiral grooves after passing through the pinching rollers as the rotating frame rotates, is wrapped around the pinching rollers. It is what it is.

According to this invention, there is a nip roller between the unwinding drum and the winding drum, and the nipping roller and the winding twist the tube between the drums, so that the twisting action is applied to the part of the tube that is on the unwinding drum. Therefore, the rewinding of the tube by the drum can be performed smoothly and without any hindrance. As a result, a long internal spiral grooved tube can be obtained continuously starting from an internal straight grooved tube, and the production thereof can be put to practical use.

Embodiments of the invention will be described below with reference to the drawings. In this specification, "front" refers to the side in the feeding direction of the tube,
In other words, it refers to the left side of the drawing.

The method for continuously manufacturing an internally spiral grooved tube, which is one aspect of this invention, first involves an internally spirally grooved tube (42) having a large number of straight grooves (42) on its internal surface as shown in FIGS. 1 and 2. 3A)
This is extruded and formed using the apparatus shown in FIGS. 4 to 8 to finally form an inner surface with a spiral groove (43) having a spiral groove (43) on the inner surface as shown in FIG. Tube (3C
) is obtained continuously.

The above device consists of a rotary frame (1) for pipe twisting and a frame rotation center I.
an unwinding drum (4) attached to the rotary frame (1) by an axis (2) perpendicular to I (C) and for rewinding the inner straight grooved tube (3A); A pair of clamping rollers (5
), and the rotating frame (1) is placed in front of the rotating frame (1).
), the twisted pipe (3B) is wound around the capstan (44) having the drums (6) and (7), and the twisted straight groove (42) forms a spiral III. The inner spiral grooved tube (3C) transformed into (43) and passed through the capstan (44) is wound on the drum (8).
It consists of a winch (45) having a.

Protruding shafts (9) (10
), and both wheels (9) and (10) are rotatably attached to front and rear stands (11 and 12) containing built-in bearings. The front protruding shaft (9) slightly protrudes from the stand (11), and a horizontally long vertical plate (13) is further provided at the tip of this. A pair of clamping rollers (5)
is attached to the rear side of the vertical plate (13).

! I! A pair of tube cross-section deformation prevention rollers (14) are attached to the straight plate (13) near the bacteria side, along with the clamping rollers (5). The tube is held between the clamp 0-ra (5) and the capstan (4).
When the previous winding (4) is twisted with the drum (6), its cross section tends to change from a perfect circle to an ellipse, but the roller (14) prevents this from happening. Sandwiching roller (5)
A groove having a semicircular cross section corresponding to half of the outer circumference of the tube (3A) is formed on the circumferential surface of the roller (14) for preventing deformation of the tube cross section (see FIG. 8).

Both rollers (5) and (14) have the same shape and are used to sandwich the tube (3A>' from above and below.) At the rear end of the vertical plate (13), that is, behind the clamping roller (5), there is a roller that pinches the tube (3A) from the left and right. The approach angle r!1 (α
) (see Figure 7) is preferably not too large. If the approach angle (α) is too large, there is a risk that cracks will occur in the pipe. It is preferable to give the tube (3A) between the unwinding drum (4) and the nipping roller (5) a slight slack so that no tension is generated.If tension is generated, the tube will crack.

In front of the rewinding drum (4), a winding tube collapse prevention device (16) is arranged opposite to it. Rolling tube collapse prevention device! (16) The rotational centrifugal force of the unwinding drum (4) accompanying the rotation of the rotating frame (1) causes the collapse of the winding form of the tube that is tightly wound spirally on the unwinding drum (4). The cylindrical base part (18) and the base all (18
) is provided with a broom-shaped pressing part (19) extending toward the unwinding drum (4), and the pressing part (19) has a length that almost reaches the surface of the unwinding drum (4) itself and a drum length. They have approximately the same width and are always biased in the direction of rotation (counterclockwise in FIG. 7) and the opposite direction (same clockwise) by a cover spring (20). The material of the floating pressing part (19) is made of synthetic resin, etc., and it presses down so as to fill the spiral grooves formed on the entire surface of the tightly wound pipe.The spring (20) is It is a tension spring,
Its upper end is fixed to the front end of a fan-shaped projection (21) extending forward from the base (18), and its lower end is fixed to the rotating frame (1).
It is fixed to a bracket (22) which is provided at the front end of the fan-shaped projection (21) and positioned below the front end of the fan-shaped projection (21). When the rewinding of the tube (3A) starts, as shown by the solid line in FIG. It is angled backwards and downwards. However, as the tube (3Δ) is unwound, the layer becomes thinner and thinner, so that the pressing part (19)
The tip moves upward, and by the time the unwinding is finished, it is almost horizontal as shown by the chain line in the same figure. However, the tube (3A), which is tightly wound spirally from the negative end on the unwinding drum (4), is always pressed by the pressing part (19) during unwinding to prevent its winding shape from being destroyed by centrifugal force. Being held down from above.

The front and rear windings of the capstan (44) are wrapped around the drums (6) (7).
) is attached by horizontal shafts (24) and (25) to the - side of the hollow tooth width box (23) placed in front of the front stand (11). For front and rear winding, the drums (6) and (7) both have a plurality of spiral grooves so that the tubes can span these properly, and the two are slightly separated and the former is positioned slightly below the latter. There is. Both horizontal axes (
24) For (25), the front and rear windings are done using drums (6) (7).
) and the gear box (23), the large gear (26)
(27) is fixed. Both gears (26) (27
), a small gear (28) meshing with these is arranged, and its horizontal shaft (29) is placed in the gear box (23). A rotary frame and capstan driving electric motor (30) is arranged behind the front stand (11), and its output shaft (31) passes through the front stand (11) and enters the gear box (23). The horizontal shaft (29) is connected to the horizontal shaft (29) via a gear or the like so as to transmit rotational force. A pulley (32) ('33
) is fixed. Both pulleys (32) (33)
A belt (34) is attached to the motor (30).
) is transmitted separately to both the capstan (44) and the rotating frame (1>). A cylindrical tube cross-section corrector (41) having a through hole with a perfectly circular cross section is attached to the gear box (23) so as to be located between them.

The shaft (35) of the drum (8), around which the winch (45) is wound, is received by a bearing (37) provided on the stand (36). A winding drum driving electric motor (38) is arranged behind the stand (36), and its rotational power is transmitted to the drum shaft (35) via a transmission mechanism (39). . On the rear side of the stand (36), a pair of horizontally movable guide rollers ( 40) is provided.

The tube wound around the unwinding drum (4) is made of extruded aluminum with many straight grooves formed on its inner surface by extrusion, but the material is not limited to aluminum.
It could also be copper or mild steel.

The twist angle of the groove is determined by the rotation speed of the rotating frame and the rotation speed of the capstan. For example, if the former speed is constant, increasing the latter speed will reduce the twist angle. Therefore, the transmission side is selected so that the required twist angle can be obtained.

In this embodiment, the tube is wound around the capstan (44) from the front drum (6), the rear winding is around the drum (7), the winding of the winch (45) is to the drum (8), and the rotating frame ( 1), twisting of the pipe occurs from the pre-winding of the capstan (44) using the pipe winding start point of the drum (6) as a fulcrum, to the pipe delivery point of the clamping roller (5), and the winding occurs. It does not occur between the return drum (4) and the nipping roller (5). However, the number of drums around which the capstan (44) is wound does not necessarily have to be two as in this embodiment, but may be one. Furthermore, it is also possible to omit the capstan (44) itself. In this case, the winding of the winch (45) uses the pipe winding start point of the drum (8) as a fulcrum, and twisting of the pipe occurs at the pipe delivery point of the nipping roller (5).

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a partially cutaway side view of a tube with a straight groove on the inside, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 4 is a side view of the entire device according to the present invention, FIG. 5 is a plan view, and FIG. 6 is a partially enlarged view of the winding tube collapse prevention device. The plan view, Figure 7 is the ■- of Figure 6.
(2) A sectional view along the ring, and FIG. 8 is an enlarged sectional view taken along the line (2)--(3) in FIG. (1)...Rotating frame for pipe twisting, (3A)...Inner straight grooved pipe, (3B)...Twisted pipe, (3C)...
・Inner spiral grooved tube, (4)...Rewinding drum, (5)
...Pinch roller 1. (6) (7) (8)... Wound on drum, (42)... Straight groove, (43)... Spiral groove. May 18, 1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono 1, Indication of the case Patent application No. 4928 of 1988
4 No. 2 Invention (D name k Continuous manufacturing method and device for internally spiral grooved pipe 3, Relationship with the person making the amendment case Patent issuer 4, agent 1 other person 5, Date of amendment order Showa year month day 6
, Number of inventions increased by amendment (1) r on page 6, line 7 of the specification (add "wo" after 47JJ. 1. Indication of the case 1982 Patent No. 49284
No. 2° 1″A′)ss Order for continuous manufacturing method and device for internally spiral grooved pipes 3, Relationship with the case of the person making the amendments Patent applicant 4, 1 outside agent 4 outsiders 5 Amendment order Date Showa year month day 6
, Number of inventions increased by amendment 7, Target of amendment Detailed description of invention column in specification. 8. Correct the word "spiral" in line 8 on page 6 of the specification of amendment to "straight line." Procedural amendment band 7 June 4, 1980 Director General of the Japan Patent Office Shima 1) Haruki Tono 1, List of cases; 1988 Patent Application No.
49284 No. 2, Title of the invention Continuous manufacturing method and apparatus for internally spiral grooved pipes 3, Relationship to the case of the person making the amendment Patent applicant 43, 1 person outside the home 5 Date of amendment order Showa year (Monday) day 6
, Number of inventions increased by amendment 7, Target of amendment Detailed description of invention column in specification.

Claims (2)

[Claims] (1) A tube with a straight inner groove is extruded, and the tube with a straight inner groove is wound onto an unwinding drum attached to a rotary frame for twisting the tube, and the tube is wound up from the unwinding drum while rotating the rotary frame for twisting the tube. The tube with an inner straight groove is passed through a pair of clamping rollers attached to the front end of the tube twisting rotation frame and unwound as it is until it reaches the clamp 1-ra, and the unwound tube is placed in front of the tube twisting rotation frame. The wrapped winding is wrapped around a drum, and the holding roller and the winding are placed between the drum, and as the rotating frame rotates, the tube is twisted, the straight groove is transformed into a spiral groove, and the inner straight grooved tube is formed. 1. A method for continuously manufacturing an internally spirally grooved tube, characterized in that the internally spirally grooved tube is continuously converted into an internally spirally grooved tube. (2) A rotating frame for twisting a pipe, an unwinding drum attached to the rotating frame and unwinding the tube with a straight groove on the inside, and a pair of clamps attached to the front end of the rotating frame and sandwiching the tube being rewound. The roller and the internal spiral grooved tube, which is placed in front of the rotating frame and whose linear grooves are twisted into spiral grooves after passing through the clamping roller as the rotating frame rotates, are unwound and unwound from the drum. Continuous manufacturing equipment for inner spiral grooved tubes.