JP2002172589A - Groove part forming method of surface film material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a groove part forming method capable of preventing inconvenient re-melting of molten resin just after forming a groove part and stabling a shape of the groove part, when the surface of the resin-made surface film material is melted and cut by an ultrasonic cutter to form a non-through groove part. SOLUTION: When the surface film material 10 constituting a resin made of interior member for a vehicle and the ultrasonic cutter 4 are relatively moved and the surface of the surface film material 10 is cut by the ultrasonic cutter 14 to form the groove part 16 with a desired length, in this groove part forming method of the surface film material, a trace member 20 having a substantially fitting shape to the groove part 16 traces the groove part 16 with pressure connection just after forming the groove part 16 in the surface film material 10 with the ultrasonic cutter 14. At this time, preferably, air is forcibly jetted to the trace member 20 or an abutting part between the trace member 20 and the groove part 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a groove in a skin material, and more particularly, to forming an unpenetrated groove by melting and incising the surface of a resin skin material with an ultrasonic cutter. The present invention relates to a groove forming method capable of stabilizing the shape of the groove.

[0002]

2. Description of the Related Art A soft type vehicle interior member represented by an instrument panel includes, for example, a base material which is a PP injection molded product and a skin material which is a PVC vacuum molded product.
It has a three-layer structure with a foam material such as urethane foam interposed. Hard-type interior parts for vehicles include polypropylene (PP) and thermoplastic polyolefin.
There is known a single layer structure of a skin material made of (TPO) or a multilayer structure in which the skin material is lined with a TPO material for reinforcing an airbag door. In many cases, the vehicle interior member made of the resin material has an airbag device incorporated therein as a safety means in the event of a collision. In this case, the safety of the occupant is ensured by instantaneously inflating the airbag upon operation of the airbag device, tearing the surface of the skin material constituting a part of the vehicle interior member and popping out. Therefore, in order to open the door of the airbag device when the airbag is operated, an opening line is formed in advance on the surface of the skin material in accordance with the contour of the door.

[0003] The predetermined tearing line is a non-penetrating groove obtained by cutting the surface of the skin material, and is easily cleaved along the predetermined line by applying a force from inside due to inflation of the airbag. That is, the airbag is allowed to inflate. In addition, outside the expected opening line of the airbag door, for example, when opening an air conditioning outlet in the instrument panel, the contour of the outlet is formed so that the air outlet can be formed by removing the part. The groove may be formed along the gap.

In order to form the groove having the required length on the surface of the skin material without penetrating, an ultrasonic cutter shown in FIGS. 7 and 8 is generally used. That is, the skin material 10 constituting a part of a vehicle interior member such as an instrument panel is placed on the support base 12, and the cutting edge 14a of the ultrasonic cutter 14 is pressed against the skin material 10 and moved in the direction of the arrow. Thus, a groove 16 having a required length and a V-shaped cross section is cut. Here, the ultrasonic cutter 14 incorporates an ultrasonic vibrator in a cutter body, and transmits ultrasonic vibration generated by the ultrasonic vibrator to the cutter blade, thereby melting the resin surface of the skin material 10. The incision is made to the required depth.
In the illustrated example, the ultrasonic cutter 14 is attached to the skin material 10.
Is moved, but conversely, the ultrasonic cutter 14
The skin material 10 may be moved with respect to.

[0005]

SUMMARY OF THE INVENTION A skin material 1 made of resin as described above.
0 and the ultrasonic cutter 14 are moved relative to each other, and the ultrasonic cutter 14 melts and incises the surface of the skin material 10 to form a groove 16 of a required length. Depending on the depth of the groove 16, It has been found that such inconveniences occur. For example, when a groove 16 having a remaining thickness of 0.8 mm (thickness from the bottom of the groove to the back surface of the skin) is cut into the 3.5 mm thick polypropylene skin material 10 with the ultrasonic cutter 14, (FIG. 9) As shown in 1), the resin 10a melted in the skin material 10 by the cutter 14 is spread in the direction of the arrow. Then, after the ultrasonic cutter 14 passes, the pressure applied by the cutter 14 is released,
As shown in FIG. 9 (2), the molten resin 10a repels in the opposite direction, flows down into the groove 16, and re-welds.

For this reason, the groove portion 16 cut in the skin material 10 and continuous in the longitudinal direction causes a difference in the tearing strength when the airbag device is activated depending on the portion, and in some cases, the deployment performance of the airbag varies. Is pointed out. After the grooves 16 are formed in the skin material 10, whether or not the processing amount is appropriate is measured by, for example, a laser beam. If the resin 10 a is re-welded to the grooves 16, accurate processing is performed. Can not measure the quantity,
Therefore, the performance cannot be guaranteed.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above-mentioned problem suitably, and the surface of a resin skin material is melt-cut with an ultrasonic cutter to form an unpenetrated groove. In this case, it is an object of the present invention to provide a groove forming method capable of preventing an inconvenient remelting of a molten resin immediately after formation and stabilizing the shape of the groove.

[0008]

SUMMARY OF THE INVENTION In order to overcome the above-mentioned problems and achieve the intended object, a method for forming a groove portion of a skin material according to the present invention comprises a method of forming a resin-made vehicle interior member with a skin material and an ultrasonic wave. The relative movement of the cutter and, when forming the groove of the required length by cutting the surface of the skin material by the ultrasonic cutter, immediately after forming the groove in the skin material by the ultrasonic cutter, this groove and The groove portion is traced in a press-contact manner by a trace member having a substantially matching shape.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a method for forming a groove in a skin material according to the present invention will be described below with reference to the accompanying drawings by way of preferred embodiments. The same or equivalent members as those described in FIGS. 7 to 9 are designated by the same reference numerals. Further, the skin material of the embodiment is assumed to be all or a part of a vehicle interior member represented by an instrument panel. However, any of the soft type and the hard type described above may be used. Good.

FIG. 1 is a schematic side view of an apparatus for carrying out a method of forming a groove of a skin material according to the present invention, wherein a skin material 10 having a required size has a support base 18 constituting a rectangular flat mounting surface.
It is placed on. An ultrasonic cutter 14 arbitrarily driven by a stepping motor on the coordinate plane in the X direction, the Y direction, and a combined direction thereof by a stepping motor, for example, is disposed above the support base 18. The material 10 can be freely contacted and separated. That is, the ultrasonic cutter 14 is forcibly pressed against the skin material 10 by a control command from a control unit (not shown), and then the ultrasonic cutter 14 is given a required coordinate motion in accordance with a required groove forming pattern. At the same time, power is supplied to an ultrasonic vibration source (not shown) of the ultrasonic cutter 14 to melt the resin constituting the skin material 10, and thereby, for example, the V-groove-shaped groove portion 16 is cut out. .

As shown in FIG. 1, on the rear side of the ultrasonic cutter 14, that is, immediately after the trajectory of the travel of the cutter 14, a trace member 20 having a cross section substantially conforming to the groove 16 is provided. The trace member 20 can trace (follow) the groove 16 immediately after the incision by pressure. The trace member 20 is basically a disk-shaped rotating body, and the ultrasonic cutter 14
The lower end of a support fork 22 attached in parallel to the rear side of the robot is freely rotatably supported via a shaft pin 24.
Note that it is not an absolute requirement that the trace member 20 be a rotating body. Although not shown, for example, even if the tip of the sled member is warped in the traveling direction, the bottom surface of the sled member has a cross-sectional shape of the groove 16. Anything can be adopted as long as it can be used in contact with. When the trace member 20 is a rotating body, the cross-sectional shape of the trace member 20 is changed along the line II-II in FIG.
As shown in FIG. 2 (1) which is a line sectional view,
It can be trapezoidal as shown in FIG. 2 (2).

Accordingly, the skin material 1 is provided by the ultrasonic cutter 14.
Immediately after the surface of No. 0 is melted and the groove 16 is formed, the resin which has been in a molten state by tracing the groove 16 by the trace member 20 by pressure is pressed outward. As a result, immediately after the formation, The shape of the groove 16 is stabilized.

Further, as shown in FIG.
Is attached to the rear side of the support fork 22 via a stay 25, and the opening of the spray tube 26 is directed to the contact portion between the trace member 20 and the groove 16. Therefore, after the groove 16 is melt-formed on the surface of the skin material 10 by the ultrasonic cutter 14, the portion where the trace member 20 traces the groove 16 is blown with air to perform early cooling. The shape of the groove 16 is further stabilized. By directing the opening of the air blowing pipe 26 to the rear side of the trace member 20, the trace member 20 may be directly cooled by the blowing air.

FIG. 3 shows a modified example in which a disk-shaped rotating body is used as the trace member 20. In this modified example, concave portions 28 are formed at required intervals on the outer periphery of the disk-shaped trace member 20. Is formed. In the illustrated example, a total of four concave portions 28 are provided at intervals of 90 degrees. Accordingly, immediately after the groove 16 is formed in the skin material 10 by the ultrasonic cutter 14, the trace member 20 is rotated by pressing the trace member 20 against the groove 16 and tracing the groove 16 as shown in FIG. Are formed at required intervals. By providing the step portions 30 at the required intervals in the groove portions 16 in this manner, it is possible to change in a direction in which the tearing strength at the cleavage scheduled line is increased.

FIG. 5 shows still another modification in which a disc-shaped rotating body is used as the trace member 20. In this modification, the outer periphery of the disc-shaped trace member 20 is arranged at a required pitch. The chevron 32 is formed continuously. Therefore, immediately after the groove 16 is formed in the skin material 10 by the ultrasonic cutter 14, the trace member 20 is pressed against the groove 16 and traced, so that the groove 1 is formed as shown in FIG.
6, the chevron steps 34 are formed at the required pitch. In this case, as shown in an enlarged view of a portion surrounded by a circle A in FIG. 5, a portion between the innermost part of the valley in the chevron-shaped step portion 34 formed on the skin material 10 and the surface of the skin material 10 is formed. Even if the thickness (remaining thickness) t is set to be thinner than the case of the groove portion 16 having a normal constant remaining thickness, the remaining thickness t occurs only locally, so that the appearance exerted on the surface of the skin material 10 is reduced. Effects are almost negligible. That is, by providing the groove 16 with the chevron steps 32 at the required pitch, while maintaining the expected tearing line of the required strength, the outer surface of the skin material 10 after the formation of the groove has a design such as uneven gloss or disappearance of grain. The fear of difficulty can be avoided.

As described above, in the method of forming the groove of the skin material according to the embodiment, the trace member 20 is formed immediately after the surface of the skin material 10 is melted by the ultrasonic cutter 14 to form the groove 16.
Thus, the groove 16 is traced by pressure.
As a result, the resin in the molten state is pressed outward, so that the shape of the groove 16 immediately after formation is stabilized. Further, in this case, for example, the air from the air blowing pipe 26 is blown onto the portion where the trace member 20 traces the groove portion 16 to cool, so that the shape of the groove portion 16 is more stably formed. Is achieved.

[0017]

As described above, according to the method for forming the groove of the skin material according to the present invention, when the surface of the resin-made skin material is melt-cut with an ultrasonic cutter to form an unpenetrated groove, Inadvertent remelting of the molten resin immediately after formation can be prevented, and the shape of the groove can be stabilized.

[Brief description of the drawings]

FIG. 1 is a schematic side view of an apparatus for performing a method of forming a groove in a skin material according to the present invention.

FIG. 2 is a cross-sectional view taken along line II-II of the groove forming apparatus shown in FIG. 1, wherein (1) is an example of a V-shaped cross section, and (2) is an example of a trapezoidal cross section.

FIG. 3 is a schematic side view showing a modified example in which a disc-shaped rotating body is used as a trace member, and shows a state where concave portions are formed at required intervals on the outer periphery of the trace member.

4 is a schematic perspective view showing a state in which steps are formed at required intervals in grooves by using the trace member shown in FIG. 3;

FIG. 5 is a schematic side view showing a modification in which a disc-shaped rotating body is used as a trace member, and shows a state in which a chevron is formed at a required pitch on the outer periphery of the trace member.

FIG. 6 is a schematic perspective view showing a state in which a chevron-shaped step portion having a required pitch is formed in a groove portion by using the trace member shown in FIG. 5;

FIG. 7 is a side view showing a state in which an ultrasonic cutter is pressed against a skin material to form a groove on the surface.

FIG. 8 is a front view of FIG. 7;

FIG. 9 is an explanatory view of a case in which a groove is cut in the skin material with an ultrasonic cutter, and (1) shows a state in which the resin melted by the cutter is spread in the arrow direction of the groove; 2) shows a state in which the molten resin rebounds in the opposite direction due to the release of the pressure after passing through the cutter and is re-welded inside the groove.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Skin material 14 Ultrasonic cutter 16 Groove part 20 Trace member 28 Concave part 32 Angle part

Claims (5)

[Claims] An ultrasonic cutter (14) and a skin material (10) constituting an interior member for a vehicle made of a resin are relatively moved, and the surface of the skin material (10) is moved by the ultrasonic cutter (14). When forming a groove (16) of a required length by making an incision, the groove (16) is formed in the skin material (10) by the ultrasonic cutter (14).
Immediately after forming the groove (16), the groove (16) is pressed and traced by a trace member (20) having a shape substantially matching with the groove (16). . 2. The method for forming a groove in a skin material according to claim 1, wherein forced air blowing is performed on said trace member (20). 3. The method according to claim 1, wherein air is forcibly blown to a contact portion between the trace member (20) and the groove (16). 4. The method according to claim 1, wherein the trace member (20) is a rotating disk, and recesses (28) are formed on the outer periphery thereof at required intervals. 5. The method according to claim 1, wherein the trace member (20) is a rotating disk, and a chevron (32) is continuously formed on an outer periphery thereof.