JPH041107B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting sheet-like sewn products such as quilting stitches.

Layered sheet-like sewn products, such as the skin of vehicle seats, are made of a material that is made by overlapping an outer fabric such as leather, a sheet of elastic material such as urethane, and a lining fabric and sewing them into multiple strips in the longitudinal direction using a multi-axis sewing machine. It is formed by cutting it to the required width.

However, when this layered material is cut, the repulsive force of the elastic material causes the seams to fray at the cut edges, causing the sewn fabric to peel off and become unusable. Conventionally, excess fraying allowance was left on both sides of the required cutting width. However, leaving extra fraying allowance required more material, resulting in wasted material and was economically disadvantageous.

In order to solve this problem, we focused on the fact that materials for the skin of vehicle seats and the like are melted by heat, and designed the cutting blade to heat up. A cutting method has been proposed in which the cut end surface is melted when cutting the material, and the ends of the sewing thread are welded to the front and back fabrics or elastic material to prevent fraying.

However, with this cutting method, depending on the heating temperature of the cutting blade, the sewing thread may not be sufficiently welded, making it impossible to completely prevent fraying, or conversely, the fabric may melt or melt more than necessary. Burns or cuts may occur, or a portion of the molten material may adhere to the cutting blade, heating electrode, etc., and these treatments require considerable effort.

Therefore, the present invention was made in view of this point.
This method attempts to eliminate the above-mentioned problems by cutting the material using ultrasonic vibration.

That is, in the present invention, a material for an overlapping sheet-like sewn product made of a thermoplastic material is sandwiched between a horn of an ultrasonic vibrator and a mold formed into a desired shape, and the material and the horn are A resonant cloth that vibrates and generates heat due to ultrasonic vibrations is inserted between the two and pressurized, and ultrasonic vibrations are applied from a horn to heat and melt the material, thereby cutting the material. The ends of the sewing thread are melted and welded to the front and back fabrics or intermediate material to prevent fraying.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a cutting device used to carry out the cutting method of the present invention. In the figure, 1 indicates the entire cutting device, and inside this cutting device 1, a plurality of ultrasonic transducers 2 are arranged in parallel. The ultrasonic transducers 2 are connected to cylinder rods 4a of cylinders 4 disposed on the upper side of the upper support 3, respectively. Each of these ultrasonic vibrators 2 is connected to an ultrasonic oscillation circuit, and a horn 5 that applies ultrasonic vibration to a material, which will be described later, is provided on the lower surface thereof. On the other hand, a horizontally elongated mold 7 with a required thickness is mounted and fixed on a surface plate 6 disposed on the floor side so as to face the horn 5 of the ultrasonic transducer 2.

The material 8 is fed between the horn 5 and the mold 7 of the cutting device 1 constructed as described above. This material 8 is used, for example, as a skin material for vehicle seats, and an elastic intermediate material 11 such as urethane is sandwiched between a front fabric 9 such as leather and a lining fabric 10 made of resin fiber. sewing thread 1
2 is constructed by overlapping stitches in multiple strips in the longitudinal direction.

A resonance cloth 13 is inserted between the material 8 and the horn 5. This resonant cloth 13 vibrates with ultrasonic vibrations and generates heat, and its material is, for example, so-called flow glass, in which glass fibers are coated with tetrafluoroethylene resin, which has excellent heat resistance and mold release properties. suitable.

Then, the material 8 is passed through the required width in a direction in which the seam direction is perpendicular to the mold 7, and then the cylinder 4
When the ultrasonic vibrator 2 is moved downward, the material 8 and the resonant cloth 13 are sandwiched between the horn 5 and the mold 7,
The horn 5 presses the material 8 and presses it against the mold 7 (see FIG. 3A). The pressure applied by this cylinder 4 is set to about 400 kg, for example.

When the ultrasonic vibrator 2 is vibrated from this state,
This ultrasonic vibration wave is first transmitted from the horn 5 to the resonant cloth 1.
As a result, the resonant cloth 13 vibrates together with the horn 5 and generates heat, and this heat is transmitted to the material 8. The ultrasonic vibrations are also transmitted to the material 8 via the resonant cloth 13, which causes the material 8 itself to generate heat.
The material 8 is melted by the heat transferred from the material 8.
Material 8 that has been melted and softened by heat in this way
is cut at the point where the mold 7 is in contact with the pressure of the horn 5 from the cylinder 4 (see Fig. 3B), and at this time, the cut end surfaces 8a and 8b of the cut material 8 are melted and the sewing thread The ends of 12 are welded to the front and back fabrics 9 and 10 or to the elastic intermediate material 11, thereby preventing fraying.

In the cutting device 1 of this example, after the material 8 is cut as described above, the ultrasonic transducer 2 is returned to its original position by the operation of the cylinder 4 again, and the cut material 8 is moved forward ( direction of arrow a)
At the same time, a new material 8 is sent to the cutting zone. At this time, since the resonant cloth 13 is made of a material with excellent mold releasability, it is easily peeled off from the material 8, so that it does not interfere with the operation of the ultrasonic transducer 2 or the movement of the cut material 8.

According to the cutting device 1 of this example configured as described above, by interposing the resonant cloth 13 between the horn 5 and the material 8, it is possible to prevent the material 8 from absorbing ultrasonic vibrations, for example. Regardless of the material, the ultrasonic vibrations are not directly absorbed by the material 8 but are transmitted to the resonant cloth 13, which causes the resonant cloth 13 to generate heat and transfer heat to the material 8, so the material 8 easily melts. , it can be cut in a short time and the cut end surface 8
A, 8b can be welded uniformly and with sufficient strength to reliably prevent separation of the front and back fabrics 9, 10 and fraying of the sewing thread 12.

Further, FIG. 4 shows another example of a cutting device used for carrying out the cutting method of the present invention, and since its constituent members are almost the same as those of the above-mentioned embodiment, the same reference numerals are given and redundant explanation will be omitted. In this example, the horn 5 of the ultrasonic vibrator 2 is placed on the bottom side of the material 8, and the surface plate 6
is connected to the cylinder 4, a mold 7 is placed on the upper surface side of the material 8, and the material 8 is pressurized by the mold 7.

Moreover, arbitrary cutting can be performed by appropriately changing the shape of the die 7 in the cutting apparatus of each of the above examples. Furthermore, the material of the resonant cloth 13 is not limited to flow glass, but may also be made of a material with good heat resistance and mold releasability.
For example, high cloth or empire cloth, which is a cloth coated with silicone or the like, may be used, and various other configurations are possible without being limited to those shown in the embodiments.

As described above, according to the present invention, the material can be easily cut and the cut end surfaces of the material can be reliably welded, so not only the peeling of the front and back fabrics but also the fraying of the sewing thread is prevented, leaving no fraying margin as in the conventional method. It is economically effective and can reduce costs, as there is no need to cut the seat trim cover, which is made by overlapping stitching of the outer skin, wadding, and lining fabric. It is.

[Brief explanation of drawings]

Fig. 1 is a schematic front view showing the first embodiment of the present invention, Fig. 2 is a partial perspective view showing an example of the material, and Figs. 3 A and B are for explanation of melt cutting of the material according to the present invention. FIG. 4 is a schematic front view showing a second embodiment of the present invention. In the figure, 2 is an ultrasonic vibrator, 5 is a horn, 7 is a mold, 8 is a material, and 13 is a resonant cloth.

Claims (1)

[Claims] 1. A material for an overlapping sheet-like sewn product made of a thermoplastic material is sandwiched between the horn of an ultrasonic vibrator and a mold formed into a desired shape, and the material is sandwiched between the material and the horn. We use resonant cloth made of flow glass, which is made by coating glass fibers with tetrafluoroethylene resin, which vibrates with ultrasonic vibrations and generates heat, and which has excellent heat resistance and mold release properties, or high cloth or empire cloth, which is cloth coated with silicone. A method for cutting an overlapping sheet-like sewn product, characterized in that the material is inserted and pressurized, and ultrasonic vibration is applied from the horn to generate heat and melt the material, thereby fusing it.