JPH10166047A - Fixing device of spiral fin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a new parts, and to firmly fix a fin to a tube as closed during the winding in fixing a spiral fin. SOLUTION: A fin 1 is joined with a tube 2 by a laser beam emission tube 32 held by an articulated robot 33 in a condition where the fin 1 initially wound around the tube 2 by an initial winding roller is pressed against the tube by a clamp roller, and after the fin winding of the prescribed quantity, the laser beam emission tube 32 is driven to join the fin with the tube in the condition where the pressing against the outer circumference of the fin is performed by the clamp roller again at the winding terminal. The spiral fin can be firmly fixed to the tube without generating loosening by the residual stress in the fin 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spiral fin tube type heat transfer system in which a continuous fin material is spirally wound around a tube used as a heat transfer part of a refrigerator, a showcase, an automobile or the like. The present invention relates to a tube manufacturing apparatus.

[0002]

2. Description of the Related Art In recent years, due to its high cost performance, a spiral fin tube type heat transfer tube made of a metal fin wound spirally on a straight tube has been used in a refrigerator, a showcase, an automobile and the like. It has been heavily used. Spiral fin tubes can be manufactured in a variety of methods, including small ones such as refrigerators, in which continuous metal fins are wound directly on a straight tube in the vertical direction and both ends are fixed to the tube. The main method is to insert a tube into a formed metal fin, spread the tube at a predetermined pitch, and fix both ends. In either method, if both ends of the fin are not fixed to the tube, springback occurs due to the residual stress when the fin is formed into a spiral shape, and the winding part is loosened, increasing the contact thermal resistance between the tube and the fin and increasing the heat. Since the exchange performance is deteriorated, it is necessary to firmly fix both ends of the fin.

A conventional spiral fin fixing method is disclosed in Japanese Patent Application Laid-Open No. 4-135014. Hereinafter, a conventional spiral fin fixing method will be described with reference to the drawings.

FIG. 7 is a perspective view showing a conventional fixing method using high-frequency resistance welding. In the figure, 1 is a fin,
2 is a tube, 3 is a pressure roll, 4 is a fin-side power supply,
Reference numeral 5 denotes a tube-side power supply. The fin 1, which is obtained by initially bending the starting end of the fin 1 to have the same diameter as the tube 2, is attached to the outer periphery of the tube 2. In this method, a high-frequency current is applied between the tube-side power supply bodies 5 and the fin and the tube are subjected to high-frequency resistance welding by resistance heat generated at a contact portion between the fin and the tube.

As another fixing method, Japanese Patent Publication No. 63-4957
There is also a fin caulking type shown in Japanese Patent Publication No.

FIG. 8 is a perspective view of a fixing method using a conventional fin caulking. The fin 1 is initially wound one or more rounds in a separate step in accordance with the inner circumference of the tube 2 in advance. The notch 6 is formed on the outer periphery of the first fin 1a.
Is formed at a position corresponding to the notch 6 of the second winding fin 1b, and the notch 6 and the notch 7 are fixed by caulking.

As still another method, there is a fin fixing method using another component as shown in FIG. In the figure, reference numeral 8 denotes a fixing part, 9 denotes a spot welding point, and 10 denotes a caulking point. In this fixing method, as shown in the figure, a fixing part 8 is attached around the tube 2, the fin 1 and the fixing part 8 are joined by spot welding to a spot welding point 9, and further, the tube 2 is crimped at a crimping point 10. And fixing parts 8
The spiral fin is fixed to the tube by caulking.

As shown in FIG. 10, a method for initial winding the fin 1 is an initial winding device comprising a turning guide 12 centering on a cored bar 11 and a clamp 13 for holding a straight portion of the fin 1. Is common.

In this initial winding device, the fin 1
Is extended with respect to the swivel guide 12, the straight portion of the fin 1 is held by the clamp 13, and the swivel guide 12 is rotated about the core 11, whereby the fin 1 is deformed with the contact portion with the core as a fulcrum. Then, the plate is bent in the width direction.

[0010]

However, in the above-mentioned fixing method by high-frequency resistance welding, it is necessary to strongly press the fin to the tube. However, a spiral fin tube applied to a refrigerator or the like has a small size and a light weight. As required, the fins are becoming thinner and wider. In such a spiral fin specification, if a pressing force is applied to perform high-frequency resistance welding between the fin and the tube, the fin will fall or bend, so that an appropriate pressing force cannot be applied. When welding is performed, normal welding conditions cannot be ensured, and there is a disadvantage that the firm fixing required for fixing the fins cannot be performed.

In the fixing method by fin caulking, the fin is wound one or more times in advance in a separate process.
The fin and the tube are fixed by attaching this to the tube and caulking, and then the fin is wound, so that the initial winding, caulking and winding are separate processes,
There is a disadvantage that productivity must be reduced due to the necessity of transferring between each process.

Further, in the above-described swaging method and the method using the fixing parts, it is not possible to fix the inside of the winding device at the end of winding, so that the spiral fin tube is completely removed from the spiral fin tube winding device after the fin winding is completed. Must be manually mounted or fixed by a dedicated device. For this reason, the fins wound in the close contact state may be loosened, and even if the loosened fins are repaired and the contact with the tube is restored, the close contact state is weakened and the heat exchange performance is reduced. I was

Further, when the fin ends are bent by the initial winding device, the bending moment required for bending the fins is constant. Therefore, as shown in FIG. The point of application of the bending load at 12 becomes farther from the metal core 11, and the load applied to the fin 1 becomes smaller.

However, when the bending angle advances and the extension distance from the core metal 11 decreases, the fin 1
When the bending load applied to the fin 1 increases and exceeds the allowable load of the fin 1 itself, the fin is deformed and the bending work around the metal core 11 is not performed. As a result, the end of the fin 1 is not completely wound around the cored bar 11 and a straight portion remains, and the outside of the fin 1 is deformed. I needed to.

It is an object of the present invention in light of the disadvantages of the prior art,
Enables strong fin fixing without the need for new parts, prevents heat exchange performance from deteriorating by fixing the wound fins in close contact, and performs initial winding in the winding device It is an object of the present invention to provide a spiral fin fixing device with higher productivity.

[0016]

In order to achieve the above object, the present invention provides a method of manufacturing a spiral fin tube by irradiating a laser beam from an emission lens barrel having an articulated robot having the beginning and end of a fin. In the initial stage, the fin and the tube contacting part are continuously joined over a predetermined length and firmly fixed, and the fin end is wound around the tube without deforming the fin using the tube as a core. This enables the winding to be stored in the winding device.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a pair of pushing rollers that rotate while sandwiching a continuous fin material, an initial winding roller that holds the winding portion of the linear portion of the fin closer to the pushing roller than the tube, A pressing roller that opposes the pressing roller and pivotally supports the outer periphery of the tube, a fin clamp that presses the wound fin against the tube, and a laser emission barrel that irradiates laser light from a laser oscillator. The fin end extended from the tube by the pushing roller was wound around the tube by the initial winding roller, the fin was wound around the tube by the pushing roller and the pressing roller, and the fin end was pressed against the tube by the clamp roller. In this state, the contact portion between the fin and the tube is irradiated with laser light to join and fix the fin and the tube.

With this arrangement, the fin and the tube are brought into close contact with each other, and the fin end is pressed with a fin clamp while the winding is completed, so that the fin and the tube are brought into close contact with each other. It can be fixed firmly by joining.

The laser beam from the laser oscillator is guided to the laser emission barrel by an optical fiber, and an articulated robot holding the laser emission barrel is provided. The fin and the tube are joined by causing the contact portion to be focused along the circumferential direction of the tube.

In this way, the fin is pressed against the tube by the clamp roller at the start and end of the fin winding, and the contact portion between the fin and the tube near the end of the fin is extended by a predetermined length along the circumferential direction without rotating the tube. Welding can be performed while keeping the curved part of the laser beam always focused on the laser beam and maintaining the optimum irradiation angle, avoiding the strength required for winding the fins and preventing the fins from coming off due to springback The welding length according to the required strength can be secured, and a firm fixation is enabled.

A cutting punch for dividing the continuous fin material into a fin end and a start end is provided, and the fin end and the fin start end are formed to have a chamfer of substantially half the fin width in the contact direction of the fin with the tube. It has a punch shape.

With this arrangement, the fin is extended from the tube by the pushing roller, and the bending is performed by applying a bending moment to the fin by rotating the initial winding roller, and a chamfer in the tube contact direction is formed at the fin end. As a result, the distance from the tube contact position to the fin end can be secured, the load required for bending can be kept below the allowable load of the fin, and the entire inner circumference of the fin can be connected to the tube without deforming the fin. The initial winding function can be built into the winding device.

Further, the center of rotation of the initial winding roller is eccentric from the winding center in the direction opposite to the pushing roller and toward the fin winding start point, and the initial winding roller return position is closer to the pushing roller than the tube by the pushing roller. And is used as a guide roller for the fin.

Thus, the contact point between the linear fin extending from the tube and the initial winding roller can be made far from the tube, the moment load can be increased, the bending can be easily started, and the turning angle can be advanced. The distance between the roller and the tube at the end position of the initial winding is smaller than the fin width at the end position of the initial winding, so that a load in the direction of pressing the fin end against the tube can be added, and the outer peripheral shape of the initial winding becomes more circular. , And can function as a fin guide roller in the winding process at the return position, and can be easily incorporated in the winding device by a simple structure.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a spiral fin fixing device according to the present invention will be described below with reference to the drawings.
The same components as those in the related art are denoted by the same reference numerals, and detailed description is omitted.

In the figure, 21 denotes a fin 1 and a tube 2
Is a winding device that spirally winds on a main body, 22 is a main body base, 23 is a slide rail, and 24 is a table.
5 is a rotary chuck, 26 is a rotary motor, and the table 24
A rotary chuck 25 and a rotary motor 26 for rotating the rotary chuck 25
Is mounted, the end of the tube 2 is clamped by the rotary chuck 25, and the tube 2 runs along the slide rail 23 while rotating the tube 2 by the rotary motor 26.

Reference numeral 27 denotes a pressing roller, and reference numeral 28 denotes a pressing motor.
7, the fin 1 is rotated by the pushing motor 28 and the fin 1 is pushed into the winding unit 29.

Numeral 30 is a laser oscillator, 31 is an optical fiber, 32 is a laser emitting barrel, 33 is an articulated robot, and laser light from the laser oscillator 30 is guided to the emitting barrel 32 by an optical fiber 31. The light is focused to one point by a focusing lens housed in the exit lens barrel 32. The position of the emission lens barrel 32 is determined by the articulated robot 33 so that the focal point 34 of the laser light is located at the contact portion between the fin 1 and the tube 2.

Reference numeral 35 denotes a cutting unit, which constitutes a general punch press in which a cutting punch 37 and a die 38 attached to a punch cylinder 36 are combined, and the fin 1 is formed with a side perpendicular to the length direction. A cutting punch 37 and a die 38 are formed in such a shape that a chamfered side having a size approximately half the width of the fin 1 is formed on both sides of the cut portion on the side to be wound around the tube 2.

A fin 1 supply unit 39 supplies the fin 1 from the punch unit 35 to the pressing roller 27 by a pair of feed rollers 40 for sandwiching the fin 1 and a feed motor 41 for rotating the feed rollers 40. is there.

The winding unit 29 has a unit base 4
2, an initial winding roller 43, a turning lever 44, a pinion gear 45, a rack 46, a holding roller 47, and an initial bending cylinder 48 are provided.

A revolving lever 44 provided with an initial winding roller 43 at one end is rotatably supported by a unit base 42, and a pinion gear 45 is fixed to a shaft portion of the revolving lever 44 installed on the back surface of the unit base 42. The initial winding roller 43 is rotated by sliding the rack 46 meshed with the roller 45 and slidably held by the holding roller 47 back and forth by the initial winding cylinder 48.

Reference numeral 49 denotes a winding center which is the center of the tube 2 on which winding is performed. Reference numeral 50 denotes a turning center of the turning lever 44. The turning center 50 is located on the opposite side of the pressing center to the winding center 49. They are eccentric in the horizontal direction and in the vertical direction to the winding start point A, respectively. In this embodiment, the two eccentrics are horizontal,
The outer diameter of the tube 2 is set to be approximately one third of the outer diameter in the vertical direction.

Further, in the return state of the initial winding cylinder 48, the outer periphery of the initial winding roller 43 is positioned so as to come into contact with a linear portion outside the winding of the fin 1 on the pushing roller 27 side from the winding start point A, and the fin 1 And has the function of a guide roller.

Reference numeral 51 denotes a pressing roller which is provided on a swing lever 53 which is supported by a swing shaft 52,
The oscillating cylinder 54 is moved so that the distance between the tube 2 and the pressing roller 51 is equal to the width of the fin 1 and the retracted position where the initial winding roller 43 does not interfere with the rotation.
Swings back and forth.

Reference numeral 55 denotes a clamp roller; 56, a clamp cylinder;
The outer diameter portion is in contact with the tube 2 and the fin 1 is pressed against the tube 2 by the clamp cylinder 56. The contact between the fin 1 and the tube 2 pressed by the clamp roller 55 The laser beam is focused on the portion and joined.

Next, the operation of the spiral fin fixing device having the above configuration will be described. The fin 1 is cut into a fin end shape in which a chamfer is formed by the cutting unit 35, is sandwiched between the feed rollers 40, and is sent between the pushing rollers 27 by the rotation of the feed motor 41. On the other hand, the end of the tube 2 is clamped by the rotary chuck 25 and passes through the winding unit 29.

In the winding unit 29, the swing lever 5
3 is moved to the retracted position by the swing cylinder 54, and the start end of the fin 1 extends through the upper surface of the tube 2 by the synchronous rotation of the pushing roller 27 and the feed roller 40. By moving the rack 46 forward, the pinion gear 45 meshing with the rack 46 is moved.
To rotate the initial winding roller 43 attached to the turning lever 44 around the tube 2 about the turning center 50 as an axis.

Since the turning center 50 is eccentric in the fin end direction from the winding center which is the center of the tube 2, the initial winding roller 43 moves from the winding start point A which is the contact point between the fin 1 and the tube 2. It contacts the fin 1 in the end direction.

When the revolving lever 44 is rotated, couples are generated at two points, a contact point between the initial winding roller 43 and the fin 1 and a contact point between the tube 2 and the fin 1, and this is a bending moment with respect to the fin 1. The fin 1 is bent at the point of contact with the tube 2 and winding around the tube 2 proceeds.
As the fin 1 is wound around the tube 2, the extension distance of the fin end from the tube 2 decreases, but the center of rotation 5
0 is also eccentric in the direction of the winding start point A, so that the distance between the initial winding roller 43 and the tube 2 decreases as the rotation angle of the swivel lever 44 advances, and the fin end rotates to follow the fin end. Go.

Since the inner peripheral side of the fin end is chamfered, a straight portion remains on the outer peripheral side of the fin end even when the inner peripheral end is in contact with the tube 2. A sufficient bending moment can be applied even when the winding of the inner peripheral end is completed by the contact of the roller 43.

When the turning angle of the turning lever 44 further advances, the distance between the initial winding roller 43 and the tube 2 becomes smaller.
Is set so that the initial winding roller 43 is separated from the fin end at a position slightly narrower than the width of the fin. As a result, the outer end of the fin is slightly pushed in the direction of the tube 2, the contact portion of the inner periphery of the fin with the tube 2 is sufficiently adhered, and the remaining straight portion is pushed in the inner periphery direction, so that the outer periphery of the fin end is wound. The initial winding of the fin end is completed without protruding from the attached outer circumference circle.

When the initial winding lever 44 is returned, the initial winding roller 43 returns to a position where it comes into contact with the outside of the linear portion of the fin 1 near the pushing roller 27 from the winding start point A, and then the rocking lever 53 is moved by the rocking cylinder 54. Is displaced to the pressing position, and the pressing roller 51 is held at a position where the distance from the tube is the width of the fin 1.

Next, when the fins are pushed in by the pushing roller 27, couples are generated at the initial winding roller 43, the winding start point A of the tube, and the pressing roller 51, resulting in a bending moment similar to that of the initial winding. The fin 1 is wound around the tube 2 by the amount that the fin 1 is pushed.

When the fin end reaches the position of the clamp roller 55, the clamp cylinder 55
Press the outer circumference of the fin end against the inner circumference with
The focal point 34 of the laser beam emitted from the laser emission column 32 held by the articulated robot 33
Is moved to move a predetermined length from the contact portion of the fin end along the curved surface of the outer periphery of the tube 2 to form a joint of a predetermined length, and the starting end of the fin 1 is Fixed to 2.

When the rotary chuck 25 is rotated from this state, the tube 2 rotates, and the fin 1 is wound from the start end of the fin 1 fixed to the tube 2. The fin 1 is pushed in by the pushing roller 27 in synchronization with this, so that winding is easily performed. Furthermore, by moving the table 24 along the slide rail 24 by a fixed amount corresponding to the rotation angle of the rotary chuck 25, spiral spiral fins at a constant interval are continuously formed in the tube 2.

When the required amount of spiral fins is formed, the outer periphery of the fin is pressed again by the clamp roller 55, and the focal point 34 of the laser beam is located at the contact portion between the fin 1 and the tube 2 in the same manner as the fixing of the fin start end. The articulated robot is driven to perform laser welding, and the fin 1 is temporarily fixed to the tube.

At the same time as the temporary fixing, the punch cylinder 36
By pressing the cutting punch 37 into the die 38 to cut the continuous fin 1 into the above-mentioned fin end shape, a fin end having a chamfer on the inner peripheral side of the winding is formed.

By continuing the winding with the feed motor 41 stopped, the fin 1 is wound around the tube 2 while leaving the starting end of the fin used for the next product in the cutting unit 29, and the fin end is the same as the starting end. Complete the winding with the shape.

When the rotary chuck 25 is further rotated, the end reaches the position of the fin clamp 55, and the outer periphery of the fin is pressed by the clamp roller 55 to be in close contact with the tube. In this operation, the fin 1 wound in close contact is not loosened until the end of the fin 1 reaches the pressing roller 51, but when the fin end passes through the pressing roller 51, the fin 1 is pressed by the fin clamp 55. Although the function of maintaining the close contact is lost for a short time, loosening occurs, but the fin 1 is already temporarily fixed to the tube 2 and the winding length up to the end is very short. Is an amount that does not cause any problem to the overall adhesion performance.

The inner periphery at the end of the fin 1 is also subjected to laser welding by irradiating the same laser beam as at the start end, so that the fin 1 is fixed to the tube 2.

In the spiral fin fixing device of the present invention, the irradiation position of the laser beam is controlled by the articulated robot 33, and the laser welding can be completed in a short time. It is also possible to irradiate and partially fix.

[0053]

As is apparent from the above description, the spiral fin fixing device according to the present invention comprises a pair of pushing rollers which rotate while sandwiching a continuous fin material, and a fin which is closer to the pushing roller than the tube. An initial winding roller that holds the winding outer side of the linear portion, a winding roller that opposes the pushing roller and pivotally supports the outer periphery of the tube, and a pressure roller that presses the wound fin against the tube; A laser emission column that emits laser light from a laser oscillator is provided. A fin end extending from the tube is pushed around the tube by a pushing roller, and the fin is wound around the tube by a pushing roller and a pushing roller. In the state where the fin end is pressed against the tube by the clamp roller, the fin and the tube are melt-bonded by irradiating the contact portion between the fin and the tube with laser light. Therefore, it is possible to firmly fix the fins without requiring any new parts, and press the fin end with a clamp roller while the winding is completed to make it tightly adhere to the tube, and contact the fin with the tube. Since the portion is irradiated with laser light and fixed, the spiral fin tube type heat transfer tube having high heat exchange performance without causing the fins to loosen can be manufactured.

Further, the laser beam from the laser oscillator is guided to the laser emission column by an optical fiber, and an articulated robot holding the laser emission column is provided. Since the fin and the tube are joined by being focused along the circumferential direction of the tube at the contact portion, the fin is pressed against the tube with a clamp roller at the start and end of fin winding, and the fin is rotated without rotating the tube. The required strength can be achieved by welding the contact part between the fin and the tube near the end while keeping the curved part along the circumferential direction always focused on the laser beam and securing the optimum irradiation angle. Therefore, a more secure fixing can be achieved.

Further, a cutting punch for dividing and cutting a continuous fin material into a fin end and a start end is provided, and the fin end and the fin start end are formed into a chamfer of approximately half the fin width in the contact direction of the fin with the tube. Since it is a punch shape, it is possible to extend the fin from the tube with the pushing roller, and to contact the entire inner periphery of the fin with the tube without deforming the fin in the initial winding and end winding. An initial winding function can be built into the device, and a highly productive fixing device that does not require a transfer process can be provided.

Further, the rotation axis of the initial winding roller is decentered from the axis of the tube in the direction opposite to the pushing roller and toward the fin winding start position, and the return position of the initial winding roller is pushed from the tube to the pushing roller. The fin guide roller is used as a fin guide roller by contacting the outside of the fin's straight part on the side, and also functions as a fin guide roller in the winding process at the return position. It is possible to make it easier to incorporate it into the winding device by using a simple structure.

In addition to fixing both ends for fixing the fins to hot water, it is also possible to partially join any part of the spiral fins, so that the fins can be prevented from loosening when forming into a complicated shape. It can also be applied as a means.

[Brief description of the drawings]

FIG. 1 is a perspective view of an entire spiral fin fixing device according to one embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of a winding unit according to the embodiment.

FIG. 3 is an operation diagram of an initial winding according to the embodiment.

FIG. 4 is a perspective view showing a fixed state of a fin start end by laser welding according to the embodiment.

FIG. 5 is a perspective view showing a fixed state of the fin end by laser welding according to the embodiment.

FIG. 6 is a perspective view showing a cutting state of the fin according to the embodiment.

FIG. 7 is a perspective view of a conventional fixing method by high frequency resistance welding.

FIG. 8 is a perspective view of a fixing method using a conventional fin caulking.

FIG. 9 is a perspective view of a conventional fixing method using another component.

FIG. 10 is a perspective view of a conventional initial winding device.

FIG. 11 is a perspective view showing a fin end shape by a conventional initial winding device.

[Explanation of symbols]

 Reference Signs List 1 fin 2 tube 27 pushing roller 30 laser oscillator 31 optical fiber 32 laser emitting barrel 33 articulated robot 37 cutting punch 43 initial winding roller 49 winding center 50 rotation center 51 pressing roller 55 fin clamp A winding start point

Claims (4)

[Claims] 1. A pair of pushing rollers that rotate while sandwiching a continuous fin material, an initial winding roller that holds the winding outside of the linear portion of the fin on the pushing roller side from the tube, and a pushing roller that faces the pushing roller. A press roller that pivotally supports the outer periphery of the tube, a fin clamp that presses the wound fin against the tube, and a laser emission barrel that irradiates laser light from a laser oscillator. The extended fin end is wound around the tube by the initial winding roller, the fin is wound around the tube by the pushing roller and the pressing roller, and the fin and tube are pressed while the fin end is pressed against the tube by the clamp roller. A spiral fin fixing device that joins the fin and the tube by irradiating the contact part with laser light. 2. An articulated robot that guides laser light from a laser oscillator to a laser emission barrel via an optical fiber and holds the laser emission barrel, and transmits the laser light emitted from the emission barrel to a fin and a tube. The spiral fin fixing device according to claim 1, wherein the fin and the tube are joined by making the contact portion of the tube be focused along the circumferential direction of the tube. 3. A cutting punch for dividing and cutting a continuous fin material into a fin end and a start end, wherein the fin end and the fin start end are formed into a chamfer of substantially half the fin width in the contact direction of the fin with the tube. 3. The spiral fin fixing device according to claim 1, wherein the spiral fin is formed in a punch shape. 4. The center of rotation of the initial winding roller is eccentric from the winding center in the direction opposite to the pushing roller and toward the winding start point of the fin, and the return position of the initial winding roller is closer to the pushing roller than the tube. Contact the outside of the fin straight part
The spiral fin fixing device according to any one of claims 1 to 3, which also serves as a fin guide roller.