JPH0717016B2 - Method for manufacturing article having foam layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to gripping articles such as assist grips and seat grips for automobiles, and articles having a foam layer and having a soft feeling, such as console box lids and armrests. It relates to a manufacturing method.

[Prior Art] Conventionally, a gripping article for supporting an occupant's body is provided in a room such as an automobile. For example, an assist grip as shown in FIG. 4 is fixed to the upper portion of the window of the rear seat or the passenger seat. The assist grip is composed of a grip portion 100 for the occupant to grip and support the body, and mounting portions 101 extending from both ends of the grip portion 100, and the mounting portion 101 is fixed to the vehicle body with screws or the like.

Conventionally, a molded product made of resin was used for this assist grip, but it was hard to say that it had a hard feel when gripped and it did not look good. Therefore, in recent years, an assist grip having a foam layer has been used. Such an assist grip is composed of a resin base material, a foam layer coated on a part of the surface of the base material, and a skin layer coated on the surface of the foam layer. The foam layer is generally provided in the central grip portion, and the base material projects from both ends of the grip portion to form an attachment portion. Also, in appearance, the surface of the grip portion and the surface of the mounting portion are usually continuous so as to be almost the same surface.

As a method of manufacturing an assist grip having such a foam layer, first, a base material having a small diameter portion is formed in the central portion, and then a soft material made of a foam layer and a skin formed by a laminating method or the like is separately used for the small diameter portion. It is usual that the grip portion is formed by wrapping it around and sewing the end portion of the soft material.

The lid of the console box is formed by forming a skin material in which a vinyl chloride sheet is laminated on the surface of a foamed sheet such as urethane foam into a predetermined shape by vacuum forming or the like. Then, the shaped skin material is placed in a mold, and a reinforcing layer is integrally formed on the back surface side of the skin material by injection molding or the like. The shape of the skin material is retained by this reinforcing layer. Then, a separately formed mounting plate (base material) is fixed to the reinforcing layer with a screw or the like, and the other end of the mounting plate is swingably fixed to the console box and functions as a lid of the console box.

[Problems to be Solved by the Invention] In the above grip article, it is not preferable that the grip portion moves relative to the base material in the axial direction or the circumferential direction. Therefore, conventionally, an adhesive layer is provided between the foam layer and the base material to integrally fix the base material and the foam layer by adhesion. Therefore, the conventional method for manufacturing a gripped article having a foam layer requires an adhering step and a sewing step, resulting in a large number of steps.

Moreover, in the case of the lid of the console box, even if the product shape is small, about 10 places are required to fix the screw, and the cost increased due to the increase in the number of parts and the productivity was poor. Also, when the lid was opened, the head of the screw was exposed, so it was not very attractive.

The present invention has been made in view of such circumstances,
An object is to easily manufacture an article having a foam layer with a reduced number of steps.

[Means for Solving the Problem] Conventionally, a vibration welding method has been used for joining resins. However, this vibration welding method is effective as long as the resins are capable of reliably transmitting vibration, but in an article having a foam layer, the foam layer absorbs the vibration, so the efficiency of conversion of vibration energy into heat energy is high. It is said that it is difficult to perform vibration welding. However, as a result of intensive studies, the present inventors have completed the present invention by discovering that vibration welding is possible if an article having a foam layer and a resin are joined together.

That is, the method for producing an article having a foam layer according to the present invention, which solves the above-mentioned problems, is directed to an adherend comprising a resin reinforcement layer and a foam layer having a design surface integrally formed on the surface of the reinforcement layer. Is held and fixed from the side of the foam layer, and a base material made of a resin that can be welded to the reinforcement layer is vibrated while being in contact with the reinforcement layer at a low frequency, and the reinforcement layer and the base material are vibrated. It is characterized by being welded and integrally joined.

The adherend is composed of a resin reinforcement layer and a foam layer. For example, in the assist grip, the adherend includes a resin core material as a reinforcing layer and a foam layer, and has a shape in which a tubular body is divided into a plurality of pieces parallel to the axial direction. That is, by combining a plurality of adherends, it is possible to form a tubular body that serves as a grip portion.

For the foam layer, a conventionally known foam such as polyurethane foam and vinyl chloride foam can be used. The reinforcing layer and the foam layer may be formed separately and then integrated by adhesion or the like, or the foam layer may be arranged as an insert in the mold to integrally form the reinforcing layer.

It is also preferable to integrally cover the surface of the foam layer with a skin made of leather, woven cloth, vinyl chloride resin or the like. As a method of covering the outer skin, a known method such as a method of arranging the outer skin in a mold at the time of foam formation and integrally molding, or a method of joining to a foam sheet by a laminating method or the like can be used.

The base material serves as a base body of the article of the present invention. For example, in the case of an assist grip, a small-diameter portion is partially formed in a substantially central portion, and the small-diameter portion is integrally covered with the adherend described above.
As the material of the base material, a resin that can be welded to the reinforcing layer is used.

In the welding step, which is a feature of the present invention, the base material and the adherend are integrally fixed by vibration welding. In this step, vibration welding is performed by vibrating the base material at a low frequency. Although it is possible to perform vibration welding by vibrating the adherend, vibration energy is not transferred well because the vibration is partially absorbed by the foam layer, and the welding strength is reduced or it takes a long time for welding. There is a problem that it costs. Therefore, in the present invention, the substrate is vibrated. The low frequency is used because it is difficult to weld through the foam layer by ultrasonic welding or the like. By vibrating the base material at a low frequency, there is little attenuation and high strength welding can be achieved in a short time.

[Operation] That is, in the method for producing an article having a foam layer of the present invention,
The adherend is held and fixed on the foam layer side, and the base material is brought into contact with the reinforcing layer. Then, by vibrating the base material at a low frequency, the surface of the reinforcing layer of the adherend and the surface of the base material slide, and are integrally welded by frictional heat.

Here, the adherend is held and fixed on the foam layer side. Therefore, there is a concern that the adherend may vibrate following the vibration of the base material due to the deformation of the foam layer, making vibration welding difficult. However, since the base material and the adherend generally have different natural frequencies, there is a difference in the phase of vibration between the base material and the adherend, and vibration welding is possible due to the difference in vibration stroke.

[Effects of the Invention] That is, according to the manufacturing method of the present invention, since the hard base material is vibrated, the vibration can be reliably transmitted to the boundary portion between the base material and the reinforcing layer, and the vibration welding can be reliably performed. Therefore, in the conventional manufacturing method, a process requiring a large number of steps such as application of the adhesive, drying of the adhesive, sewing or screwing can be avoided, and the number of steps can be reduced. It is also easy to automate.

If multiple types of adherends with different skin materials covering the foam layer are prepared, it is possible to easily manufacture articles according to the grade, and it is possible to produce other types with a small number of parts. .

In the gripped article obtained by the manufacturing method of the present invention, the gap between the gripped portion and the base material can be almost zero, and the appearance is good. Further, since the grip portion has the foam layer and is securely welded to the base material, a soft feeling is obtained and relative movement with respect to the base material is prevented.

Moreover, in the lid of the console box and the like obtained by the manufacturing method of the present invention, the head of the screw does not appear on the surface of the base material when the lid is opened, and the appearance is improved.

[Examples] Hereinafter, specific examples will be described.

Example 1 FIGS. 1 to 4 show the assist grip obtained in this example. This assist grip has a grip 100 and a mount 101.
And a substantially U-shaped base material 1 and an adherend 2 provided at the center of the base material 1. A small diameter portion 10 is formed in the center of the base material 1, and the adherend 2 is integrally fixed to the small diameter portion 10.

The adherend 2 includes a core material 20 as a reinforcing layer having a shape obtained by dividing a substantially cylindrical body in half, and a foam layer 22 integrally bonded to the core material 20.
And a skin 23 bonded to the surface of the foam layer 22.
Then, the core material 20, the foam layer 22 and the skin 23 are integrally bonded and fixed together.

(Base Material Forming Step) A substantially cylindrical base material 1 is formed by injection molding using a polypyroprene resin mixed with a filler, a pigment and the like. A small-diameter portion 10 is formed in the central grip portion of the base material 1, and the small-diameter portion is formed.
On the outer peripheral surface of 10, two rib portions 11 having a cross-shaped cross section are formed extending in the axial direction.

(Adhering material forming step) A core material 20 is formed by injection molding in the same manner as the base material 1 from a polypyroprene resin in which the same fillers and pigments as those of the base material 1 are mixed.
To form. The core material 20 is slightly shorter than the length of the small-diameter portion 10, and a groove 21 that engages with the rib portion 11 is formed on the end surface extending in the longitudinal direction. Two pieces of the core material 20 are formed for one base material 1. When the core material 20 is combined with the base material 1 into a tubular shape, the inner diameter thereof is substantially equal to the outer diameter of the small-diameter portion 10,
The outer diameter is substantially equal to the outer diameter of the portion other than the small diameter portion 10.

Next, the core material 20 is placed in a molding die in which a leather-made skin material is placed, and by integral foam molding using urethane foam, a foam layer 22 and a skin are formed on the outer surface and both end surfaces of the core material 20. Form 23. As shown in FIG. 3, the foam layer 22 covers the outer surface and both end surfaces of the core material 20 and is integrally bonded to the core material 20 to form the adherend 2 as a whole.

(Welding Step) Next, two adherends 2 are arranged in the small diameter portion 10 and each groove 21 is engaged with the rib portion 11 to form a tubular shape. Then, the adherend 2 is held and fixed by a pressing jig, and in this state, the base material 1 is vibrated at a low frequency of 800 μm in amplitude and 200 Hz in frequency. At this time, the foam layer 22 coated on both end surfaces of the core material 20 is compressed by the wall portion 12 at the end of the small diameter portion 10 of the base material 1, so that the amplitude during vibration welding is secured, and the base material 1 The core material 20 and the core material 20 are integrally welded. In addition, the engagement between the rib portion 11 and the groove 21 has a large joint area, and a high bonding strength can be obtained. As a result, as shown in FIG. 4, an assist grip composed of the soft grip portion 100 and the hard mounting portion 101 can be obtained.

That is, according to the manufacturing method of the present embodiment, the hard base material 1 is vibrated, and the vibration is surely transmitted to the boundary surface between the base material 1 and the core material 20, so that welding is performed with high strength in a short time. be able to. Since the gap extending in the circumferential direction at the boundary between the adherend 2 and the base material 1 can be set to zero, the appearance is good. In addition, a boundary line extending in the axial direction appears at the abutting portion of the two adherends 2, which gives a unique appearance and is excellent in design. Since it is not necessary to perform a large number of steps such as bonding and sewing as in the conventional case, the number of steps can be reduced and the cost can be reduced.

(Embodiment 2) FIG. 5 shows a sectional view of a lid of a console box manufactured in this embodiment. This lid comprises a polypropylene (PP) base material 3 and an adherend 4.

As shown in the perspective view of FIG. 6, the base material 3 has a plurality of ribs 30 on the surface facing the adherend 4, and the tips of the ribs 30 are welded to a reinforcing plate 40 described below to form the adherend 4. It is fixed integrally with.

The adherend 4 is a PP reinforcing plate 40 and a PP foam 41 and a PP foam 41 that are integrally joined to the reinforcing plate 40 and have a foaming ratio of 15 to 20 times.
The surface 42 is made of vinyl chloride resin (PVC). This adherend 4 consists of PP foam 41 and PV
A sheet integrally bonded to the C skin 42 by a laminating method is formed into a predetermined shape by vacuum forming. Then, the shaped skin material is placed in the mold, and the reinforcing plate 40 is formed by injection molding and integrated, and the shapes of the PP foam 41 and the skin 42 are retained by the reinforcing plate 40.

The welding of the base material 3 and the adherend 4 was performed as follows. That is, as shown in FIG. 7, first, the adherend 4 is first
Hold and fix to the receiving jig 50. At this time, the skin 42 is the first receiving jig.
The reinforcing plate 40 is arranged so as to abut on 50 and to be exposed upward.

Next, the base material 3 is placed so that the ribs 30 contact the reinforcing plate 40, and the base material 3 is held by the second receiving jig 51. Then, the first receiving jig 50 and the second receiving jig 51 are driven toward each other, and the reinforcing plate 40 and the rib 30 are pressed against each other with a load of 500 kgf. In this state, the second receiving jig 51 is vibrated in the extending direction of the rib 30 (the arrow direction in FIG. 7). The vibration was performed under the conditions of an amplitude of 1.5 mm on one side and a frequency of 120 Hz.

As a result, the surface of the reinforcing plate 40 and the tip surface of the rib 30 were welded, and the base material 3 and the adherend 4 were integrally joined. Although the end of the base material 3 and the end of the skin 42 of the adherend 4 were in contact with each other during vibration, no load was applied to that part, so welding did not occur and the appearance was not impaired. .

Therefore, according to the manufacturing method of the present embodiment, the step of fixing the base material and the reinforcing plate with a screw or the like as in the conventional case is unnecessary, so that the productivity is improved. Further, in the obtained lid, the head such as a screw does not appear on the surface of the base material 3 when the console box is opened, so that the appearance is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show a gripping article obtained by a manufacturing method according to a first embodiment of the present invention, and FIG.
2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view taken along the line B- of FIG.
It is sectional drawing equivalent to B. FIG. 4 is a perspective view of the assist grip. 5 to 7 relate to the second embodiment of the present invention, FIG. 5 is a sectional view of the lid of the obtained console box, FIG. 6 is a perspective view of the main part of the base material, and FIG. It is explanatory drawing explaining the welding method. 1, 3 ... Base material, 2, 4 ... Adhering material 10 ... Small diameter portion, 11 ... Rib portion, 12 ... Wall portion 20 ... Core material, 21 ... Groove portion 22 ... Foam layer, 23 …… Skin 30 …… Rib, 40 …… Reinforcement plate 41 …… PP foam, 42 …… PVC skin

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location B29K 105: 06 B29L 31:58 (72) Inventor Norio Jogishi Kasuga-cho, Nishikasugai-gun, Aichi Ochiai-ji Nagahata No. 1 Toyoda Gosei Co., Ltd. (72) Inventor Hiroshi Suyama Large-scale Ochiai, Kasuga-cho, Nishikasugai-gun, Aichi Nagahata No. 1 Toyoda Gosei Co., Ltd. (56) Reference JP-A-4-10921 (JP, A)

Claims (1)

[Claims] 1. An adherend comprising a resin reinforcing layer and a foam layer having a design surface integrally formed on the surface of the reinforcing layer is held and fixed from the foam layer side, and the reinforcing is performed. A base material formed of a resin that can be welded to a layer is vibrated in a state of being in contact with the reinforcing layer at a low frequency, and the reinforcing layer and the base material are vibration-welded and integrally joined. And a method for producing an article having a foam layer.