JP3577470B2 - Method and apparatus for processing linear grooves in airbag portion of automobile skin - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
SUMMARY OF THE INVENTION The present invention relates to a resin skin such as vinyl chloride (PVC), polyolefin (TPO), or polyurethane (TPU) for forming an instrument panel for a vehicle, for example, in order to ensure the safety of a passenger in the event of a vehicle collision. The present invention relates to a method and a processing apparatus for processing a linear groove for allowing breakage at a location where a destructive force of a certain degree or more is applied to an airbag portion.
[0002]
[Prior art]
The linear grooves to be processed on the airbag part of the resin-made skin for automobiles are required to be processed not on the front side of the skin but on the back side of the skin from the viewpoint of design, and the linear grooves are mounted. Since it is closely related to the safety of a person, it is required to perform processing so as to exhibit a constant and reproducible fracture resistance. In order to meet such demands and demands, in recent years, means for processing a linear groove from the back side of the skin so as to leave a predetermined thickness on the front side of the skin has been generally adopted.
[0003]
By the way, as means for processing a linear groove from the back side of the skin, conventionally, (a) means for processing a linear groove by mechanically cutting a resin material using a knife-shaped cutter or the like; As disclosed in, for example, JP-A-10-85966, means for processing a linear groove by irradiating a laser beam to locally incinerate and remove a resin material is known.
[0004]
[Problems to be solved by the invention]
However, in the case of the mechanical processing means of the above (a), even if the processing is performed from the back surface side of the skin, it is a technique to cut off so as not to expose a linear processing mark on the front surface side of the skin serving as a design surface. It is difficult in nature and causes great damage in design. In this type of processed product, it is important to measure the remaining wall thickness on the skin surface side after processing the linear groove and record and save data for each processed product from the viewpoint of quality control. In the case of the processing means, since the groove width is narrow and both sides of the groove are in close contact with each other due to the elastic force of the resin material immediately after the excision, it is difficult to accurately measure the remaining wall thickness. It is not preferable from the viewpoint.
[0005]
On the other hand, in the case of the laser processing means (b), although it is possible to process a predetermined linear groove without damaging the design surface (skin surface), a large output power is required and power consumption is high. And the processing cost increases. In particular, to process wide grooves that are easy to accurately measure and record the remaining thickness, which is important for quality control, use a laser beam generator with enormous output power or compare It is necessary to trace the laser beam generator having a small output power a plurality of times along the planned processing line, and as a result, there is a problem that the processing cost is further increased.
[0006]
Further, in order to process a linear groove having a reproducible constant breaking resistance by leaving a predetermined thickness on the surface of the skin by laser processing means, it is necessary to use a resin material corresponding to variations in the thickness of the skin. It is necessary to delicately control the incineration removal amount, that is, the processing depth of the groove, but there is no other method than controlling the output power of the laser beam generator, and advanced technology is required for processing control itself .
[0007]
In addition, in the case of laser processing, the resin material in the skin corresponding to the linear groove to be processed is incinerated and removed, so that a considerable amount of soot is generated and released during the processing, and this released. If soot gets into the machined grooves, it causes a variation in the measured value of the remaining wall thickness. In order to avoid this, it is necessary to suppress the generation of soot by using an inert gas together, and it is necessary to add a device that actively sucks and removes soot. Was a problem.
[0008]
The present invention has been made in view of the above circumstances, and not only can avoid damage to the design surface, can be reproduced with a predetermined thickness remaining on the surface of the skin under low power consumption and simple control Provided is a method and apparatus for processing a linear groove in an airbag portion of an automobile skin, which can efficiently process a linear groove having a constant breaking resistance in a state advantageous for measuring the remaining wall thickness. It is intended to be.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a method for forming a linear groove in an airbag portion of an automobile skin according to the present invention is a method of leaving a predetermined thickness on the surface side of an airbag portion of an automobile resin skin. In the method of processing a linear groove from the back side of the skin, the vibration horn of the ultrasonic processing device arranged on the back side of the skin while the skin is fixed and held so that the surface is in close contact with the flat surface. After adjusting the position so that the clearance between the tip and the flat surface matches a predetermined remaining thickness on the surface of the skin, a linear groove to be processed between the ultrasonic processing device and the heating device and the flat surface for fixing the skin. The airbag portion of the skin is preheated and softened by the heating device by the relative movement in the direction of, and the resin for the skin is sequentially applied by applying ultrasonic vibration to the back side of the softened airbag portion via the vibration horn. Melt and remove It is characterized in that for processing a linear groove.
[0010]
In addition, the apparatus for forming a linear groove in an airbag portion of an automobile skin according to the present invention is characterized in that a wire is formed from the rear surface side of the airbag portion of an automobile resin skin in a state where a predetermined thickness is left on the surface side thereof. A surface plate that fixes and holds the skin so that its surface is in close contact with a flat surface, and an ultrasonic wave that is arranged on the back side of the skin and applies ultrasonic vibration to the resin for the skin A processing device, a heating device provided on the upper side in the moving direction of the ultrasonic processing device for preheating the airbag portion of the epidermis immediately before applying ultrasonic waves, and processing the ultrasonic processing device, the heating device, and the surface plate. And a processing position moving mechanism for relatively moving in the direction of the power linear groove.
[0011]
According to the present invention having the above constitutional requirements, the resin-made skin is fixed and held so that the surface thereof is in close contact with the flat surface, and the flat surface is used as a reference surface (zero) for the vibration horn of the ultrasonic machining apparatus. The tip position is adjusted in the skin thickness direction so that the clearance between the horn tip and the flat surface matches the predetermined thickness to be left on the skin surface side. In this state, by relatively moving the ultrasonic processing device and the heating device and the flat surface for fixing the skin in the direction of the linear groove to be processed, first, the airbag portion to be processed of the skin was preheated and softened. Then, ultrasonic vibration is sequentially applied to the back surface side of the airbag portion of the skin via the vibration horn of the ultrasonic processing device, and the resin for the skin at that location is melted and removed to process the linear groove. In this way, the airbag portion is preheated and softened just before the ultrasonic vibration is applied, and the stress during ultrasonic processing is dispersed to avoid damage to the design surface on the skin surface side where the ultrasonic vibration is applied. It is possible to do.
[0012]
In particular, vibration horns of various widths and shapes already exist, and by selecting and using an appropriate width and shape from among them, the ultrasonic processing device can be traced once along the planned processing line. It is possible to process a groove having a wide width and a predetermined depth simply by causing the resin material for the skin to be melted and the melted resin to be removed to the side, as in the case of mechanical processing. The linear processing trace is not exposed on the surface side, and it is possible to eliminate damage to the design surface also on this surface. In addition, processing control for processing a linear groove having a reproducible constant breaking resistance by leaving a predetermined thickness on the skin surface side also adjusts the position of the vibration horn in response to the skin thickness variation. It is possible to employ such a simple mechanical control as described above.
[0013]
Furthermore, the molten resin generated by the ultrasonic processing is only removed to the side of the groove and hardened, but does not enter the groove. Therefore, as in the case of laser processing, the generation of soot due to the groove processing is reduced. It is possible to reduce the equipment cost of the whole device by eliminating the means for suppressing and removing the generated soot by suction at all. It is possible to improve the measurement accuracy by eliminating the cause of the variation in the quality of the processed product, and to accurately perform the quality control of the processed product.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram of an entire processing apparatus used in carrying out a method of processing a linear groove in an airbag portion of an automobile skin according to the present invention, and FIG. 2 is an enlarged side view of a main part thereof.
[0015]
1 and 2, reference numeral 1 denotes a surface plate having a large number of small holes 1b formed in a flat upper surface 1a thereof. The air in the cavity 1c is sucked by a vacuum generator 2 such as a vacuum pump to reduce the pressure. In this way, the airbag portion of the automotive resin skin 3 placed on the flat upper surface 1a is adsorbed through the small holes 1b and fixedly held so that the surface 3a is in close contact with the flat upper surface 1a. An ultrasonic processing device 4 for applying ultrasonic vibration to the resin for the skin is disposed above the surface plate 1 on the back surface 3b side of the skin 3. This ultrasonic processing apparatus 4 is composed of an ultrasonic oscillator 4A having an oscillation frequency of 20 to 40 KHz, an ultrasonic vibrator 4B, and a vibration horn 4C which is integrally processed from an iron alloy and a titanium alloy and has a cut blade cut out. A plurality of types of vibration horns 4C having different widths and shapes are interchangeably attached to the ultrasonic vibrator 4B.
[0016]
The ultrasonic vibrator 4B and the vibration horn 4C of the ultrasonic processing device 4 have a predetermined thickness such that a clearance t1 between the tip of the vibration horn 4C and the flat upper surface 1a of the surface plate 1 should remain on the surface 3a side of the skin 3. The vibration horn 4C is mounted on a processing position adjusting mechanism 5 that can move the tip position of the vibration horn 4C in the thickness direction of the skin 3 (the direction of arrows ud) so as to coincide with t (see FIG. 3). The machining position adjusting mechanism 5 sets the tip position of the vibration horn 4C in accordance with the input of the thickness T of the skin 3 which is known or detected at the time of machining, with the flat surface 1a of the surface plate as a reference plane (zero). A mechanism for moving to a height position obtained by subtracting the remaining thickness t from the thickness T. Specifically, a well-known mechanism combining a telescopic device such as a cylinder and a control unit for calculating and outputting a required movement amount. Therefore, the description and illustration of the specific structure will be omitted.
[0017]
In addition, the ultrasonic processing device 4 and the processing position adjusting mechanism 5 move the direction (arrow) of the linear groove 6 (see FIG. 3) to be processed on the back surface 3b side of the airbag portion of the skin 3 with respect to the surface plate 1. It is mounted on a processing position moving mechanism 7 which can be driven and moved in the X direction). As the processing position moving mechanism 7, for example, a well-known conveyor such as a belt conveyor or a chain conveyor can be used, and the description and illustration of the specific structure are omitted.
[0018]
A temperature controller that blows warm air to the back surface 3b of the skin 3 as a heating device that preheats a processed portion of the skin 3 immediately before applying ultrasonic vibration to the upper side of the processing position moving direction X of the ultrasonic processing device 4. A hot air generator 8 with 8a is arranged, and cooling air is applied to the back surface 3b of the skin 3 immediately after the ultrasonic processing, on the lower side of the processing position moving direction X of the ultrasonic processing device 4. A cooling air ejection device 9 to be blown is provided, and immediately after the cooling air ejection device 9, the remaining thickness t of the linear groove 6 formed on the back surface 3b of the skin 3 is measured and recorded from the side of the skin back surface 3b. For example, a laser displacement sensor and a CCD camera 10 are provided as a device for performing the operation. As a heating device for preheating the processed portion of the skin 3, an electric heater or the like may be used instead of the hot air generator 8, and a laser displacement sensor and a CCD A transmission type photoelectric sensor may be used instead of the camera 10. Further, the hot air generator 8, the cooling air ejection device 9, the laser displacement sensor and the CCD camera 10 are configured to move integrally with the ultrasonic processing device 4 in the processing position moving direction X via the processing position moving mechanism 7. Have been.
[0019]
Next, a method of processing the linear groove 6 in the airbag portion of the automobile skin 3 using the processing apparatus having the above configuration will be described.
First, the processed portion (airbag portion) of the resin skin 3 is placed on the flat upper surface 1a of the surface plate 1 with its surface 3a facing downward, and the air in the cavity 1c is sucked by the vacuum generator 2 Then, the processed portion of the resin skin 3 is adsorbed through the small holes 1b..., And the skin 3 is fixed and held on the surface plate 1 so that the surface 3a is in close contact with the flat upper surface 1a.
[0020]
Next, the ultrasonic vibrator 4B and the vibration horn 4C of the ultrasonic processing device 4 are moved via the position adjustment mechanism 5 to the tip of the vibration horn 4C and the flat upper surface 1a of the surface plate 1 in accordance with the thickness T of the skin 3 to be processed. The flat top surface 1a of the surface plate 1 is used as a reference plane (zero) so that the clearance t1 with the predetermined thickness t to be left on the surface 3a side of the skin 3 is equal to the skin thickness direction (arrow ud direction). ), The processing position of the ultrasonic processing device 4 is initially adjusted.
[0021]
Thereafter, when the ultrasonic processing device 4 is integrally moved in the processing position moving direction X together with the hot air generator 8, the cooling air ejection device 9, the laser displacement sensor and the CCD camera 10 via the processing position moving mechanism 7, The hot air generated by the hot air generator 8 is blown onto the back surface 3b of the skin 3, and the processed portion of the skin 3 immediately before the ultrasonic processing is preheated and softened, and the softened portion is super-softened through the vibration horn 4C. The linear groove 6 having the predetermined thickness t left on the surface 3a side is subjected to the sonic vibration, and the stress at the time of this processing is dispersed and applied to the design surface on the surface 3a side of the skin 3. Damage is avoided.
[0022]
As shown in FIG. 3, the resin portions 3d that are sequentially melted by the ultrasonic processing by applying the ultrasonic vibration are removed on the outer surface 3b on both sides of the processed linear groove 6, and this position is removed. Is immediately cured by the cooling air blown from the cooling air jetting device 9, so that the molten resin portion 3d does not enter the processed linear groove 6, and the wide groove 6 is reliably processed. can do.
[0023]
Immediately after the ultrasonic processing is completed as described above, the processed linear groove 6 is scanned from the back surface 3b side of the skin 3 by the laser displacement sensor and the CCD camera 10, and the remaining thickness t is obtained by processing the photographed image. Is measured and recorded, and is effectively used as quality control data for processed products.
[0024]
In the above-described embodiment, a case has been described in which the processing position by the ultrasonic processing device 4 is only initially adjusted in accordance with the thickness T of the skin 3, but the remaining thickness t during actual ultrasonic processing is reduced. In the case where the skin 3 that may fluctuate more than the allowable value with respect to the target value is to be processed, the position adjusting mechanism 5 is operated to adjust the feedback method so that the remaining thickness t falls within the allowable error range. It is desirable that the mechanical adjustment mechanism 5 be used, so that such feedback-type adjustment can be easily realized.
[0025]
【The invention's effect】
As described above, according to the present invention, as the linear groove processing means from the back surface side of the resin skin, the processed portion is softened by the preheating immediately before the heating device, and then the ultrasonic vibration by the ultrasonic processing device is used. By doing so, a wide groove can be processed only by tracing once along the planned processing line, and the molten resin generated by ultrasonic processing is removed to the side of the groove and hardened, Since foreign matter can be prevented from entering the surface, linear processing marks such as in the case of mechanical processing are not exposed on the surface side, and the stress at the time of processing is dispersed to reduce damage to the design surface. Can be avoided. In addition, it is possible to adjust the machining position corresponding to the variation in the thickness of the skin by simple mechanical control, and efficiently create a linear groove with a predetermined thickness remaining on the surface of the skin and a reproducible constant breaking resistance. Can be processed. In addition, as in the case of laser processing, there is no need for any means for suppressing the generation of soot due to the groove processing and means for sucking and removing the generated soot, and processing is achieved by reducing equipment costs and power consumption of the entire apparatus. It is possible to easily and accurately measure the remaining thickness of the skin surface after groove processing from the back side while achieving significant cost savings, and it is possible to accurately control the quality of processed products. It works.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an entire processing apparatus used when performing a method of processing a linear groove in an airbag portion of an automobile skin according to the present invention.
FIG. 2 is an enlarged side view of a main part of FIG.
FIG. 3 is an enlarged longitudinal sectional view of a main part for explaining a processed linear groove and a peripheral state thereof.
[Explanation of symbols]
1 Surface plate 1a Flat upper surface 3 Resin skin for automobile 3a Skin surface (design surface)
3b Back surface of skin 4 Ultrasonic processing device 4C Vibration horn 5 Processing position adjusting mechanism 6 Linear groove 7 Processing position moving mechanism 8 Hot air generator (one example of heating device)
10 Laser displacement sensor and CCD camera (example of residual thickness measurement and recording device)
t Clearance t1 between the flat upper surface and the tip of the vibration horn Remaining wall thickness

Claims (2)

A method of processing a linear groove from the back side of the skin in a state where a predetermined thickness is left on the front side of the air bag portion of the resin-made skin for the automobile,
With the epidermis fixed and held so that its surface is in close contact with the flat surface,
After adjusting the position of the vibration horn of the ultrasonic processing device arranged on the back surface side of the skin so that the clearance between the tip and the flat surface matches the predetermined remaining thickness on the skin surface side,
The ultrasonic processing device and the heating device and the flat surface for fixing the skin are relatively moved in the direction of the linear groove to be processed, and the airbag portion of the skin is preheated and softened by the heating device, and the softened airbag portion is removed. Applying ultrasonic vibration to the back side through a vibration horn to melt and remove the resin for the skin in order to form a linear groove. Method. An apparatus for processing a linear groove from the back side of the skin in a state where a predetermined thickness is left on the front side of the air bag portion of the resin-made skin for the automobile,
A surface plate that fixes and holds the epidermis so that its surface is in close contact with the flat surface,
An ultrasonic processing device arranged on the back side of the skin to apply ultrasonic vibration to the resin for the skin,
A processing position adjusting mechanism for adjusting the position of the vibration horn of the ultrasonic processing apparatus so that the clearance between the tip and the flat surface of the surface plate matches a predetermined remaining thickness on the skin surface side,
A heating device that is provided on the upper side in the moving direction of the ultrasonic processing device and preheats an airbag portion of the skin immediately before applying ultrasonic waves,
A straight line to the airbag portion of the car skin, comprising an ultrasonic processing device, a heating device, and a processing position moving mechanism for relatively moving the surface plate in the direction of the linear groove to be processed. Grooving equipment.

Images