JPS6312373A - Partial painting method - Google Patents

Abstract

PURPOSE:To execute excellent painting at a low cost by sticking a tape to the position of a work including a parting line and cutting the position corresponding to the parting line by a laser. CONSTITUTION:The tape 11 having a suitable width is stuck over the entire length of the work 1 surface in the position including the parting line in partial painting to a resin molding, etc. The tape 11 stuck across the two parts; a painting part 2 and a non-painting part 3 in the above-mentioned manner is cut by the laser light from an emission unit to be moved so as to exactly profile the parting line 5. The tape part 11a of the painting part 2 is thereafter stripped from the work and the non-painting part is masked. The painting part 2 is painted and the remaining tape part 11b and masking member are removed from the work. The operating stage is thus simplified and the excellent painting is executed at a low cost.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a partial coating method suitable for applying partial coating, color coating, etc. to resin molded products, metal molded products, etc. be.

(Prior Art) In recent years, in order to improve the appearance of automobile parts and other molded products, it has become common practice to apply partial coating, color-specific coating, etc. to the molded products.

By the way, in order to make the appearance of the molded product stand out with this kind of painting, it is important to make the boundary line between the painted part and the non-painted part, or in other words, the parting line, clear. Various proposals have been made to ensure the clarity of the cutting line.

FIG. 2 is a diagram showing an example of this, and here, the upper half of a resin bumper 1 as an example of a workpiece is painted with a painted part 2.
When the lower half is the unpainted part 3, in order to apply the required coating only to the painted part 2, first cut off one side edge of the polyester parting tape 4.
4IA5 is affixed to the non-painted part 3 in a state where it has been accurately defeated, and the required part of the non-painted part 3, in this case the entirety, is covered with a paper masking member 6, and then painted. Paint is applied to the entire portion 2 using a paint gun or the like, and after the paint dries, the parting tape 4 and the masking member 6 are removed from the bumper 1.

Therefore, in this conventional painting method, there is a problem in that the number of man-hours required to align the side edge of the parting tape 4 accurately with the parting line 5 and attach it is significantly increased. In addition to this, there is a problem in that a high level of skill is required when the workpiece is hidden or the surface shape of the workpiece is complex.

Therefore, as disclosed in JP-A No. 60-227863 and JP-A No. 60-227868, a strippable paint applied to the surface of the workpiece is applied with a laser beam at a position that exactly corresponds to the parting line position. Cut and then remove the strippable paint located on the painted part,
A proposal has been made to make it possible to apply paint to the painted area by peeling it off at the cutting position, thereby solving the problems associated with adhesion of parting tape.

(Problem to be solved by the invention) However, with this proposed technology, in addition to the high cost of strippable paint, painting equipment is required to apply it, so the painting cost is considerable. Laser cutting of strippable paint has the problem of bulkiness, and it is virtually impossible to maintain a uniform coating thickness no matter how you apply it. In areas where the coating thickness is too thick, sufficient cutting cannot be performed, while in areas where the coating thickness is too thin, scratches may occur on the surface of the workpiece.

The present invention advantageously solves the problems of the prior art, and provides a partial painting method that can bring about a sufficient reduction in painting costs without causing any problems related to attaching parting tape or laser cutting. It provides:

(Means for Solving the Problems) The partial coating method of the present invention is a method for painting a workpiece at a position on the surface of the workpiece that includes the parting line between the painted part and the non-painted part, or in other words, at a position that straddles both of these parts. After pasting a tape made of paper, synthetic resin, etc. on the surface, the tape is laser cut in the length direction at a position that corresponds exactly to the parting line, and then the tape is pasted on the painted part. After peeling off only the tape part from the workpiece, masking the necessary non-painted parts with a masking material made of paper, synthetic resin, etc., and applying paint to the painted parts by an appropriate method, It consists of removing the remaining tape portion and the masking member from the workpiece.

(Function) According to this method, the tape can be attached to the work simply by roughly positioning the tape having an appropriate width to the actual or latent parting line. Therefore, even if the surface shape of the workpiece is complex, the adhesion can be completed in a short time without requiring a high degree of skill.

In addition, since a tape having a uniform thickness over the entire length is attached to the surface of the workpiece, the workpiece can always be properly cut without causing surface scratches or other inconveniences when laser cutting the tape. be able to.

(Example) The present invention will be explained below based on illustrated examples.

FIG. 1 is a process diagram showing an embodiment of this invention, and in the figure,
Portions similar to those described in the conventional example are designated by the same numbers.

That is, 1 is a resin bumper as an example of a workpiece,
2 is a painted part, 3 is a non-painted part, and 5 is a parting line between both parts.

Here, first, a tape 11 made of paper, synthetic resin, etc. and having an appropriate width, for example, a polyester tape with a width of 15+++ m, is placed on the bumper surface at a position including the parting point vA5, as shown in FIG. 1(a). Glue along its entire length. Here, in order to ensure sufficient adhesion of the tape 11 to the bumper surface, it is preferable to rub the tape with a finger or the like one or more times.

In this way, the tape 11 pasted over both the painted part 2 and the non-painted part 3 is then exposed to the laser beam from the emission unit that is moved along the parting line 5 of the bumper 1. Cut using light as shown in FIG. 1(b).

In addition, as shown in FIG. 1(b), the laser beam generated by the oscillator 12 is sent to the output unit 14 via an optical fiber 13 having a diameter of 0.2φ, for example, and after being focused there, the laser beam is transferred to the tape. 11 will be irradiated. Here, the type and output of the laser, the output unit 1
4 and the tape 11, the moving speed tL of the output unit 14, etc. can of course be selected appropriately depending on the material, thickness, etc. of the tape 11. For example, if the tape 11 is made of polyester, Its thickness is 10-100μ
In this case, a YAG laser with an output of IOW is used, and the emission unit 14 is set at 50±511III
By moving the tape 11 further apart and at a speed of 10 m5/sec, the necessary and sufficient cutting of the tape 11 is achieved.

In addition, if the emission unit 14 is moved by a robot, cutting can be performed with extremely high precision regardless of whether the laser cutting line is a straight line or a curved line.

Next, as shown in FIG. 1(c), of the cut tape 11, the tape portion 11a stuck on the painted portion is peeled off from the bumper surface, and the required portions of the non-painted portion 3 are removed. , the entire area is covered with a masking member 15 made of paper, for example, as shown in FIG. 1(d).

Further, after that, a urethane-based paint, for example, is applied to the painted portion 2 by a required method, using a paint gun 16 in FIG. 1(d), and after the paint is completely dried by baking drying or other Before the paint is completely dry, the remaining tape portion 11b stuck to the non-painted portion 3 and the masking member 15 are removed from the bumper 1.

Therefore, here, the tape 11 can be applied in an extremely short time without requiring any skill, and the tape 11 can also be cut properly at all times without excess or deficiency.
Moreover, there is no need to use expensive strippable paint or other painting equipment as in the proposed technique, resulting in a significant reduction in painting costs.

Although the present invention has been described above based on illustrated examples, the present invention can also be used when painting workpieces in multiple colors, and can also be applied to other types of resin molded products and metal molded products. The same can be applied.

(Effects of the Invention) Therefore, according to the present invention, a tape is pasted on a workpiece at a position including a parting line, and the tape is later cut with a laser at a position that exactly corresponds to the parting line position. By doing so, you can not only make the parting line after painting extremely clear and make the appearance of the workpiece stand out, but also reduce the number of man-hours and other costs when attaching the side edge of the tape to the parting line. Excellent coatings can be produced at low cost without any problems associated with laser cutting of strippable paints, such as equipment and other costs, and the depth and depth of cutting.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing an embodiment of the present invention, and FIG. 2 is a perspective view showing a conventional example. 1... Resin bumper 2... Painted part 3...
Non-painted part 5... Parting line 11... Tape
11a...Tape portion 11b...Remaining tape portion 14...Emission unit 15...Masking member 16...Painting gun patent applicant Nissan Motor Co., Ltd. Figure 1 (a)

Claims (1)

[Claims] 1. Painted part (2) and non-painted part (3) of the work surface
After pasting the tape (11) to the workpiece (1) at a position including the parting line (5), the tape is cut by laser at a position corresponding to the parting line, and then the coating After peeling off the tape part (11a) located in the part from the workpiece, masking the non-painted part, and applying paint to the painted part, the remaining tape part (11b) and the masking member (15b) are removed. A partial painting method characterized by removing the material from the workpiece.