JP4113752B2 - Joining device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a joining technique of pipe materials, and in particular, by irradiating a surface of a joint with a laser beam in a state in which ends of a pair of pipe materials are fitted in the joint, each pipe material and the joint are fused. It is related to the technology.
[0002]
[Prior art]
[Patent Document 1]
JP 9-239839 A
[Patent Document 2]
JP2000-320984
When joining pipe materials such as gas pipes and water pipes, an electric welding joint 60 shown in FIG. 12 has been used so far. The joint 60 includes a cylindrical body 62 made of synthetic resin, and has a structure in which a heating wire 64 is embedded in a coil shape along an inner peripheral surface thereof.
In the state where the end of one tube 66 is inserted from one end opening of the cylindrical body 62 and the end of the other tube 68 is inserted from the other end opening, both terminals 70 and 72 of the heating wire 64 are inserted. When a predetermined voltage is applied to the tube, the inner peripheral surface of the tubular body 62 and the outer peripheral surfaces of the pipe members 66 and 68 are welded by Joule heat from the heating wire 64.
By using this electric welding joint 60, it becomes possible to join the pipe materials at the site where a gas pipe or a water pipe having a limited space is installed.
[0003]
[Problems to be solved by the invention]
However, in this joining method, it is necessary to use the electric welding joint 62 in which the heating wire 64 is internally provided for each joining portion as described above, and the heating wire 64 is disposable as a matter of course. Therefore, there was a problem from the viewpoint of resource saving.
In addition, due to the nature of gas pipes and water pipes, there should be no leakage from the seam, but there is a problem in that it is not possible to easily check on the spot whether or not it has been completely welded by the conventional joining method. there were. Actually, in the case of heating with the heating wire 64, temperature unevenness tends to occur depending on the portion, and it has been difficult to uniformly join the inner peripheral surface of the cylindrical body 62 and the outer peripheral surfaces of the pipe members 66 and 68.
Furthermore, after welding is completed by heating from the heating wire 64, it is necessary to naturally cool the joint portion, and a considerable waiting time is required until the next process is started, resulting in poor workability. It was.
[0004]
Although mechanical welding methods such as the vibration method and the bat method have been proposed instead of using the electric welding joint 60 incorporating the disposable heating wire 64 in this way, both of them are in terms of workability and required time. It was not satisfactory.
Alternatively, it is theoretically possible to weld a pipe made of a thermoplastic resin such as polyethylene and a joint using an extreme solvent, but it has not been practically available from the viewpoint of health damage or environmental pollution.
[0005]
The present invention has been devised to solve the above-described problems of conventional joining methods, and it is possible to easily and quickly lay pipe materials together at a construction site without using a disposable heating wire or a dangerous solvent. It is an object to provide a technique that can be joined and that can easily check the joining condition.
[0006]
[Means for Solving the Problems]
In order to achieve the above-described object, a pipe material joining method according to the present invention includes a pair of pipe materials having at least an outer peripheral surface made of a resin via a resin joint having a laser beam and visible light permeability. When joining, a step of arranging a laser absorber on at least one of the inner peripheral surface of the joint and the outer peripheral surface of the pipe, a step of inserting one end of the pipe into the opening of the joint, and an outer peripheral surface of the joint A step of heating the laser absorber interposed between the inner peripheral surface of the joint and the outer peripheral surface of the pipe by irradiating a laser beam, and the inner peripheral surface of the joint and the pipe by heat conduction from the laser absorber And a step of fusing between the outer peripheral surfaces of the two.
[0007]
In this way, the outer peripheral surface of the joint is irradiated with a laser beam, and the inner peripheral surface of the joint and the outer peripheral surface tube of the pipe material are fused by the heat generation action of the laser absorber. Without any problem, the pipe materials can be joined to each other via a joint.
Further, by using a semiconductor laser capable of reducing the size and weight of the entire apparatus as a laser oscillation source, it is possible to perform on-site construction.
Since the heat treatment by the laser is instantaneous and local, there is an advantage that the next operation can be performed without securing a long cooling time.
In addition, since the joint is transparent to visible light, the degree of fusion between the pipe and the joint based on the heat generated by the laser absorber can be seen from the outside, and if a defective joint is found, it can be handled on the spot. It becomes. By using a substance that changes color when irradiated with a laser beam as the laser absorber, the degree of fusion can be more clearly confirmed.
[0008]
Further, the joining device according to the present invention inserts at least one end of a pipe member whose outer peripheral surface is made of resin into an opening of a resin joint having a laser beam and visible light transmittance, A coupling body joining device in which a laser absorber is disposed between an inner peripheral surface and an outer peripheral surface of a pipe material, and is a circular rail member having a notch portion, and is introduced into the rail member from the notch portion. Means for fixing the coupling body at the center of the rail member, a laser head slidably engaged with the rail member and irradiating a laser beam on the outer peripheral surface of the joint, and the laser head mounted on the rail It is characterized by comprising means for moving along the member, means for rotating the rail member left and right by a required amount, and means for moving the rail member forward and backward by a required amount.
[0009]
When a coupling body of a pipe and a joint is fixedly arranged at the center of the rail member and the laser beam is irradiated while moving the laser head along the rail member, the laser beam is incident on the outer peripheral surface of the joint. And when a laser absorber is heated with the laser beam which permeate | transmitted the joint, between the internal peripheral surface of a joint and the outer peripheral surface of a pipe material will fuse | melt by the conduction heat.
Since the connecting body is disposed and fixed at the center of the circular rail member, the distance between the laser head and the incident position of the laser beam is always constant.
Since the rail member is provided with a notch for introducing the coupling body, a non-incident portion remains on the circumference of the outer peripheral surface of the joint only by moving the laser head. This can be dealt with by moving the laser head in the opposite direction after rotating the rail member itself in a predetermined direction at a predetermined angle.
Further, by moving the rail member in the front-rear direction, it is possible to irradiate the laser beam in a direction intersecting with the circumference on the outer peripheral surface of the joint.
[0010]
A plurality of rail members and laser heads are provided, and each rail member and laser head are positioned and arranged so that each laser head can irradiate a laser beam on the same circumference on the outer peripheral surface of the joint. Can be realized.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a method for joining pipes according to the present invention will be described with reference to the accompanying drawings. First, as shown in FIGS. 1 and 2, one end of each of the first pipe member 12 and the second pipe member 14 to be joined is inserted into both end openings of the cylindrical joint 10 to form a connection body 16. .
The joint 10 is made of a resin material having transparency to a laser beam and visible light. However, the joint 10 does not need to be a completely transparent body, and may be a translucent body.
The first tube material 12 and the second tube material 14 are each made of a synthetic resin material such as polyethylene or nylon 12, and a laser absorber 18 is formed on the outer peripheral surface of the end portion in a film form. The laser absorber 18 is made of, for example, resin powder mixed with methyl ethyl ketone and a phthalocyanine dye.
As a result, the laser absorber 18 is interposed between the inner peripheral surface of the joint 10 and the outer peripheral surfaces of the end portions of the pipe members 12 and 14 (FIG. 2).
[0012]
Next, as shown in FIG. 3, the connecting body 16 is loaded into the first joining device 20.
The first joining device 20 includes at least a laser head 22, a rail member 24 for guiding the laser head 22, and a chuck mechanism 28 including three gripping members 26 that can be opened and closed.
The rail member 24 is made of a metal material such as stainless steel or aluminum and has a circular shape with a part cut away.
As shown in FIG. 4, the rail member 24 includes a guide groove 30, and a transfer wheel 32 of the laser head 22 is fitted into the guide groove 30.
[0013]
A drive box 34 incorporating an electric motor is connected to the laser head 22, and a drive shaft 36 of the motor is connected to the center of the wheel 32.
A flexible cable 38 is connected to the rear end of the laser head 22. The cable 38 contains an optical fiber for transmitting a laser beam output from a laser oscillator (for example, a semiconductor laser oscillator) (not shown) and a power supply line for supplying a power supply voltage to the motor. Yes.
By driving the electric motor, the laser head 22 can move along a circular track along the rail member 24.
[0014]
A plurality of rods 40 are connected to the back surface of the rail member 24.
These rods 40 are configured to rotate left and right along the circumference of the rail member 24 and to slide back and forth by the action of a drive mechanism (not shown).
As a result, the rail member 24 can be moved back and forth by the required amount in response to the sliding operation of each rod 40, and can be rotated to the left and right by the rotating operation of each rod 40.
[0015]
Next, as shown in FIG. 5, the gripping member 26 of the chuck mechanism 28 is closed toward the center of the rail member 24 to hold the outer peripheral surface of the coupling body 16, and then the laser head 22 is moved to the rail while continuously irradiating the laser beam L. Move along the member 24.
As a result, the laser beam L is irradiated along the outer peripheral surface of the joint 10, and the laser absorber 18 is heated by the laser beam L transmitted through the joint 10. Due to the transmission heat from the laser absorber 18, the outer peripheral surface of the first pipe member 12 and the inner peripheral surface of the joint 10 are melted, and the two are hermetically joined.
However, as described above, the rail member 24 does not form a perfect circle, and the cutout portion 42 for introducing the connecting body 16 is formed, so that the laser beam L makes a round around the outer peripheral surface of the joint 10. Cannot be formed, and a certain unbonded portion 44 is generated.
[0016]
For this reason, when the laser head 22 reaches the end portion 45 of the rail member 24, as shown in FIG. 6, the rail member 24 itself is turned leftward by a predetermined angle, and then the laser head 22 is moved in the reverse direction. Move.
As a result, it is possible to reliably irradiate the unbonded portion 44 on the surface of the joint 10 with the laser beam L.
[0017]
As described above, after joining the joint 10 and one of the pipe members 12, the rod 40 is moved in the front-rear direction by a necessary amount, and the same joining operation is repeated a plurality of times, whereby each of the pipe members 12, 14 And the joint 10 can be joined at a plurality of locations.
In addition, with the laser head 22 fixed to one point of the rail member 24, the rail member 24 is moved back and forth by the action of the rod 40, and at the same time, the laser beam L is irradiated from the laser head 22, whereby the joint 10 and each pipe member It becomes possible to join between 12 and 14 in a grid pattern. As a result, the joint strength between the pipe materials 12 and 14 and the joint 10 can be dramatically increased.
[0018]
The laser absorber 18 usually has a light green color due to the influence of the phthalocyanine dye, but is heated and melted by irradiation with the laser beam L, and after being fused between the upper and lower resins, it turns colorless and transparent. It has the characteristic of doing.
For this reason, as shown in FIG. 7A, the color of the laser absorber 18 passes through the joint 10 and rises to the surface before joining.
Next, as shown in (b), after the laser beam L is irradiated from the laser head 22 and the joint 10 and the pipes 12 and 14 are fused, the irradiated portion becomes transparent, thereby forming an annular shape. Will appear. Incidentally, (b) shows a state in which a plurality of fusion lines α are formed along the circumference by moving the rail member 24 back and forth.
Further, (c) shows a state in which a lattice-like fusion line α appears by irradiating the laser beam L while moving the rail member 24 back and forth.
[0019]
As described above, the fusion line α appears at the portion where the joining by the irradiation of the laser beam L is completed, and this can be visually recognized from the surface of the joint 10, so that the joining condition can be easily obtained at the construction site of the pipe. Can be checked.
In addition, since heating and melting by irradiation with the laser beam L is completed extremely instantaneously, the cooling time can be greatly shortened as compared with the case of heating and melting with a heating wire.
[0020]
As described above, instead of configuring so that the colorless and transparent fusion line α appears when joining by irradiation with the laser beam L is completed, as shown in FIGS. Of course, it is also possible to configure so that the fusion line β appears.
In this case, for example, the laser absorber 18 in which black carbon powder is fixed to the outer peripheral surfaces of the pipe members 12 and 14 via a predetermined binder is used, and a milky white translucent body is used as the joint 10.
As a result, as shown in (a), the color of the laser absorber 18 does not appear clearly on the surface of the joint 10 before the joining.
On the other hand, when the inner peripheral surface of the joint 10 and the outer peripheral surfaces of the pipe materials 12 and 14 are joined by irradiation with the laser beam, as shown in (b) and (c), between the joint 10 and the pipe materials 12 and 14. This gap disappears and the two are completely in close contact with each other, so that the color of the laser absorber 18 rises to the surface of the joint 10 as a fusion line β.
As a result, similarly to the above, it is possible to visually recognize the joint condition between the joint 10 and the pipe members 12 and 14 from the outside.
[0021]
In the above description, the first bonding apparatus 20 including one laser head 24 has been described. However, it is naturally possible to use a bonding apparatus including a plurality of laser heads and rail members that can be independently driven.
That is, the second joining device 50 shown in FIG. 9 and FIG. 10 includes a first rail member 24a and a second rail member 24b arranged at a constant interval, and each rail member 24a, 24b. Laser heads 22a and 22b are connected to the guide grooves 30 via wheels 32, respectively.
Each rail member 24a, 24b has a circular shape with a part cut away.
[0022]
Thus, at the start of the joining operation, after the laser heads 22a and 22b move to one end of each rail member 24a and 24b, the laser beam L is applied to the opposite end along the rail members 24a and 24b. Move towards.
At this time, the laser heads 22a and 22b and the rail members 24a and 24b are positioned so that the laser beams L from the laser heads 22a and 22b are irradiated on the same circumference on the surface of the joint 10.
[0023]
In the second joining apparatus 50, since each laser head 22a, 22b only has to share the surface of the joint 10 by half, the efficiency and speed of the joining operation can be realized.
When the connecting body 16 is taken in and out, as shown in FIG. 11, one rail member 24a is rotated by the operation of the rod 40, and a gap 52 is provided between the other rail member 24b.
[0024]
In the above description, the example in which the resin pipe materials 12 and 14 are fused via the resin joint 10 has been described. However, the present invention can also be applied to the joining of pipe materials having a resin coating on the surface of a metal material. .
In the above description, an example in which the laser absorber 18 is previously attached to the outer peripheral surfaces of the pipe members 12 and 14 has been described. However, the present invention is not limited to this. For example, a sheet-like laser absorber can be interposed between the outer peripheral surfaces of the pipe members 12 and 14 and the inner peripheral surface of the joint 10, or a gel-like laser absorber 18 can be interposed.
[0025]
【The invention's effect】
According to the method for joining pipes according to the present invention, the pipes can be connected to each other without using a heating wire as in the prior art. Further, by using a semiconductor laser capable of reducing the size and weight of the entire apparatus as a laser oscillation source, it is possible to perform on-site construction. Since the heat treatment by the laser is instantaneous and local, there is an advantage that a long cooling time is not required. In addition, since the joint has visible light transmission, the degree of fusion between the pipe and the joint based on the heat generated by the laser absorber can be seen from the outside, and if a defective joint is found, it can be handled on the spot. It becomes. By using a substance that changes color when irradiated with a laser beam as the laser absorber, the bonding condition can be recognized more clearly.
Moreover, according to the joining apparatus which concerns on this invention, it becomes possible to implement said joining method effectively.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state in which one end of each of a first tube material and a second tube material is inserted into both end openings of a cylindrical joint to form a coupling body.
FIG. 2 is a cross-sectional view showing the connection body.
FIG. 3 is a front partial cross-sectional view showing a state in which the coupling body is loaded into the first joining device.
FIG. 4 is a side partial cross-sectional view showing a state in which the coupling body is loaded in the first joining device.
FIG. 5 is a partial front sectional view showing a state in which a laser beam is irradiated on the surface of the coupling body.
FIG. 6 is a partial front sectional view showing a state in which a laser beam is irradiated on the surface of the coupling body.
FIG. 7 is an explanatory view showing a state where a transparent fusion line appears on the surface of the joint.
FIG. 8 is an explanatory view showing a state in which a colored fusion line appears on the surface of a joint.
FIG. 9 is a front partial cross-sectional view showing a state in which the coupling body is loaded in a second bonding apparatus.
FIG. 10 is a side partial cross-sectional view showing a state in which the coupling body is loaded in a second bonding apparatus.
FIG. 11 is a front partial cross-sectional view showing a state where the connecting body is taken out from the second joining apparatus.
FIG. 12 is a cross-sectional view showing a conventional method for joining pipe materials using an electroweld joint.
[Explanation of symbols]
10 Fitting
12 First pipe
14 Second pipe
16 Linkage
18 Laser absorber
20 First joining device
22 Laser head
24 Rail member
26 Gripping member
28 Chuck mechanism
30 Guide groove
32 Transfer wheel
34 Drive box
36 Motor drive shaft
38 cable
40 rods
42 Notch
44 Unjoined part
45 End of rail member
50 Second joining device
52 Clearance L Laser beam α Fusion line β Fusion line

Claims (2)

Inserting at least one end of a pipe material whose outer peripheral surface is made of resin into an opening of a resin joint having laser beam and visible light permeability, and connecting the inner peripheral surface of the joint and the outer peripheral surface of the pipe material It is a joining device for a joined body in which a laser absorber is disposed between
A circular rail member with a notch, and
Means for fixing the coupling body introduced into the rail member from the notch in the central portion of the rail member;
A laser head that is slidably engaged with the rail member and irradiates a laser beam on the outer peripheral surface of the joint;
Means for moving the laser head along the rail member;
Means for rotating the rail member to the right and left by a necessary amount;
And a means for moving the rail member forward and backward by a required amount. A plurality of rail members and laser heads;
Bonding apparatus according to claim 1, by each laser head, characterized in that each rail member and the laser head so as to allow a laser beam on the same circumference is positioned and arranged on the outer peripheral surface of the joint.

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