JPH059774U - Nozzle for laser cutting machine - Google Patents

Abstract

(57) [Abstract] [Purpose] Efficiently and highly accurately cuts a work that is unstable in shape. A tip member 5 having a curved surface 5b formed around the through hole and having one side cut along a surface 5c parallel to the axis of the through hole is rotatably attached to the tip of the nozzle body 1. Done
The nozzle for cutting machine. When the nozzle body is moved along the cutting line, it moves while pressing the frayed portion of the glass fiber generated on the surface with the cutting of the work by the inclined surface of the tip member, which may hinder the movement of the nozzle. Without, the work can be cut accurately. Further, when the direction of the cutting line changes, the tip member rotates to cause the flat surface portion to automatically follow the copying portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a laser cutting machine nozzle used for cutting and molding a reinforcing fiber mat or the like.

[0002]

[Prior Art]

 Recently, fiber reinforced resin (FRP) has come to be used for outer panels of automobiles. At the time of molding the FRP, a preform mat in which reinforcing fibers such as glass fibers are previously formed into a predetermined shape is used. Conventionally, as shown in FIG. 3, the preform mat is cut and formed by placing a work W preformed with glass fiber or the like on a pedestal 10 and covering it with a cover 11 and cutting line shown in FIG. 3B. The nozzle 1 of the laser cutting machine is moved along 12 to cut around the work to finish it into a predetermined shape. Japanese Utility Model Application Laid-Open No. 57-65786 discloses a laser cutting pedestal having a conical upper half portion, and Japanese Utility Model Application Laid-Open No. 60-20381 discloses a laser cutting machine nose. There is described a copying apparatus of a laser processing machine in which a contact surface which is vertically movable and presses a workpiece and a distance sensor are provided on the tool, and a detection plate is installed immediately below the distance sensor. Japanese Utility Model Laid-Open No. 60-108492 discloses a laser processing nozzle in which a nozzle body is divided into a fixed nozzle and a movable nozzle, and a movable ring is provided with a shield ring.

In the above-mentioned conventional cutting method, the preform mat molded from glass fiber or the like is unstable in maintaining its shape, and the work after molding is more than twice the set thickness at the time of press molding. Since a bulge (spring back) occurs, a clamp jig is used when finishing cutting with a laser cutting machine. In this clamp jig, as shown in FIG. 2, upper and lower presser plates 7 and 8 each having an inverted shape of a molded product are installed on a support frame 6, and a work W is sandwiched between them. The upper presser plate 8 is pressed by a clamp mechanism (not shown) to keep the thickness of the work W to a predetermined value, and the laser nozzle 1 is cut along the cutting line 9 by using a multi-function Cartesian coordinate robot. I try to move and disconnect.

[0004]

[Problems to be solved by the device]

 The nozzle 1 needs to be efficiently cut at a portion of the laser beam having a large energy density by aligning the focus of the laser beam with the center of the thickness of the work W, and the nozzle 1 can be cut as much as possible. Unless it comes close to the edge 8a of the upper presser plate 8, the work W at the cutting line 9 bulges, and the front surface and the back surface of the work W are out of focus of the laser. Cutting residue occurs, and the burning rate of the binder used for the work W decreases, so that carbides tend to remain on the work W. However, since the glass fiber is frayed on the surface of the work W after cutting and hangs on the tip of the nozzle 1, the accuracy of the movement trajectory of the nozzle 1 is impaired. For this reason, the tip of the conventional nozzle 1 cannot be brought close to the surface of the work W, and it is cut several millimeters away from the work surface, so that the energy of the laser beam is reduced. There is a problem that cannot be used effectively. Further, it is desirable that the tip portion of the nozzle 1 be formed in a thin shape, but it is necessary to provide a jet passage of the assist gas in order to prevent the combustion products from adhering to the condensing lens 2. There is a limit to the reduction of the aperture size. Therefore, there is a limit to how close the nozzle 1 can be to the edge of the clamp jig. The present invention solves the above problems and allows the tip of the nozzle to be brought as close as possible to the surface of the work and the edge of the clamp jig, and the work can be performed at a portion where the energy density of the laser beam is large. It is an object of the present invention to provide a nozzle for a laser cutting machine that can efficiently cut a workpiece with high precision.

[0005]

[Means for Solving the Problems]

 According to the present invention, a tip member having a curved surface around the through hole and having one side cut along a plane parallel to the axis of the through hole is rotatably mounted on the tip of the nozzle body. The nozzle for a cutting machine.

[0006]

[Action]

 When the nozzle body is moved along the cutting line, it moves while pressing the sloping surface of the tip member against the frayed parts of the glass fiber that are generated on the surface when the work is cut, which hinders the movement of the nozzle. It is possible to cut the work with high accuracy without the risk of being damaged. Further, when the direction of the cutting line changes, the tip member rotates to automatically cause the plane portion to follow the copying portion.

[0007]

【Example】

 1 shows an embodiment of the present invention, and FIG. 1A is a sectional view taken along line XX of FIG. 1B showing a bottom surface. An assist gas supply pipe 3 is arranged in the nozzle body 1 to which the condenser lens 2 is attached, and a tip member 5 is rotatably attached to the tip portion of the nozzle body 1 via a bearing 4. The tip member 5 has a central hole 5a, and the surface around the central hole 5a is formed into a curved surface having a radius R and an inclined surface 5b with an angle α continuous with the curved surface. The tip member 5 is made parallel to the axis of the central hole 5a. The side is cut along the plane 5c. The laser beam passing through the condenser lens 2 passes through the central hole 5a and focuses on the position F at a distance a from the tip of the tip member 5a.

Next, the cutting of the work by the laser nozzle of the present invention will be described. As shown in FIG. 2, a work W preformed with glass fiber or the like is placed on the lower presser plate 7, and the work W is covered with the upper presser plate 8 to be illustrated. Do not press the upper presser plate 8 with the clamping mechanism. If the distance a between the surface of the tip member 5 and the focal point F shown in FIG. 1 is 2.75 mm and the thickness b of the work W is 1.5 mm, the tip of the tip member 5 is 2 mm away from the surface of the work W. When set to the position, the focal point F of the laser beam is located at the center of the thickness of the work W. The nozzle body 1 is brought close to the end edge of the upper presser plate 8 and the tip member 5 is rotated so that the flat surface portion 5c is parallel to the end edge 8a of the upper presser plate 8 and the tip member 5 Can be brought as close as possible to the edge of the upper presser plate 8. Therefore, the cutting line 9 can be preset at such a position.

While supplying air or nitrogen gas at 2 kg / cm ² from the gas supply pipe 3, the nozzle body 1 is moved along the cutting line 9 with the tip of the tip member 5 separated from the surface of the work W by 2 mm. When this is done, the nozzle body 1 moves while pressing the slanted surface 5b of the tip member 5 at the location where the glass fibers are frayed due to the cutting of the work W, so that there is no risk of hindering the movement of the nozzle. , The work W can be accurately cut. Further, when the direction of the cutting line 9 changes, the tip member 5 supported by the bearing 4 rotates to automatically follow the flat surface portion 5c of the upper pressing plate, which is a copying portion, to the edge 8a. Let The shape of the surface 5b of the tip member 5 must be determined according to the degree of weaving of the glass mat, but generally R = 3 mm or more and α = 5 degrees or more.

[0010]

[Effect of the device]

 According to the present invention, when a work having an unstable shape such as a glass fiber mat is cut by a laser cutting machine, there is no problem even if the tip of the laser nozzle is brought close to the work surface. Therefore, the focus of the laser beam can be adjusted to the work and cut efficiently, and when using the work clamp jig, the nozzle tip should be close to the edge of the jig. The work can be cut with high precision.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a cut state of the present invention.

FIG. 3 is an explanatory view of a conventional cutting jig.

[Explanation of symbols]

1 Nozzle body 2 Condenser lens 3 Gas supply pipe 4 Bearing 5 Tip member 7 Lower presser plate 8 Upper presser plate 9 Cutting line W work
Ku

Claims (1)

[Claims for utility model registration] [Claim 1] A front end member of a nozzle body is formed by forming a surface around the through hole into a curved surface and cutting one side by a plane parallel to the axis of the through hole. A nozzle for a laser cutting machine, which is rotatably attached to the nozzle.