JPH06319631A - Headrest stay - Google Patents

Abstract

PURPOSE:To make a headrest stay lightweight, increase the strength and prevent rusting by coating a pipe-like metal core material with a colored plastic material mixed with reinforcing fibers such as glass fibers to form an outer layer, and forming coupling step sections on the outer layer. CONSTITUTION:The outside of a pipe-like metal core material 1 is coated with a colored plastic material to form an outer layer 2. The plastic material of the outer layer 2 is mixed with reinforcing fibers such as glass fibers. Coupling step sections 3 and a lug 4 below them are concurrently and integrally molded at a headrest insertion section on the surface of the outer layer 2 by the injection of a resin into a die. The release of a stay from a headrest is prevented, it is made lightweight, it has sufficient strength, and the stay requiring no rustproof treatment is readily manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headrest stay for supporting a headrest provided on an upper portion of a backrest of an automobile seat or the like so that the headrest can be moved up and down.

[0002]

2. Description of the Related Art A headrest stay having an upper end fixed to a headrest and a lower end inserted into a backrest portion and engaging with a locking device provided on the backrest portion at a desired height is subjected to a large impact on the headrest during a vehicle collision. However, it is necessary to protect the passengers so that they do not break or bend badly. Therefore, most of the conventional headrest stays use solid metal rods. A groove for engagement has been formed on this metal rod in order to engage with the lock device.

[0003]

The conventional headrest stay using a metal rod is sufficient in terms of strength, but its weight is increased, and it also requires labor for plating to prevent rust. Due to pollution problems, the plating plant is forced to relocate to a place far away from the place of consumption, resulting in high transportation costs. Furthermore, in order to reduce the weight and reduce the cost, the core body of the headrest is often molded recently from a plastic material. Since the metal rod and the plastic core body have different specific heats, they are solidified by cooling after molding the plastic material. At times, sink marks may occur at the contact points with the metal rods, which may cause defective molding.

Therefore, the present invention has sufficient strength,
An object of the present invention is to provide a headrest stay that is light in weight, does not require anticorrosion treatment, does not require post-processing for forming an engaging portion, and is excellent in adhesion to a plastic core body.

[0005]

In order to achieve the above-mentioned object, the present invention comprises a metal core material coated with a plastic material to form an outer layer, and an engaging portion formed on the outer layer.

[0006]

In the present invention, since the stay is formed from a composite of metal and plastic, it is lighter than a solid metal rod, and a proper combination of both materials provides sufficient strength. Further, since the metal is covered with the plastic, no rust prevention treatment is required, and the engaging portion can be integrally formed when the plastic is molded. Further, when the core body of the headrest is molded from a plastic material, the core body and the stay can be easily bonded at the time of molding the core body, and since they are plastics, the bonding strength is high.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

In the embodiment shown in FIG. 1, a metal core 1 is covered with a plastic material to form an outer layer 2, and an engaging portion 3 is formed on the outer layer 2. It is preferable to mix reinforcing fibers such as glass fibers into the plastic material forming the outer layer 2. Further, by mixing the outer layer 2 with a coloring agent, the headrest stay can be colored easily.
The core material 1 is formed of a pipe-shaped member made of a steel material having an outer diameter of 8 mm. The wall thickness of this pipe-shaped member is 1.2 to
It was set to 1.5 mm. Furthermore, as the plastic material forming the outer layer 2, a plastic material having excellent abrasion resistance such as nylon is suitable, and the outer diameter is 12.7 mm.
The wall thickness is about 2.3 mm. Further, in some countries, there is a standard that the headrest stay for automobiles should not come out of the backrest. In such a case, the protrusion 4 is integrally formed when the outer layer 2 is formed on the lower end side. I'll do it.

FIG. 2 shows a case where the headrest stay of the present invention is molded by injection molding. A pin 12 for supporting the core 1 at both ends is arranged between the upper mold 10 and the lower mold 11 so that the pin 12 can be inserted and removed freely. The core material 1 is supported in the cavity 13.
Further, the lower mold 11 is formed with a protrusion 14 for forming the engaging portion 3. The outer layer 2 that covers the outer periphery of the core material 1 is molded by injecting a plastic material into the cavity 13 from the injection port 15 of the upper mold 10. At this time, the engaging portion 3 is also integrally formed. If necessary, a recess may be formed in the upper mold 10 and the lower mold 11 so that the protrusion 4 can also be formed.

FIG. 3 shows a case where a headrest 21 is attached to a backrest portion 20 of an automobile seat via a headrest stay of the present invention (hereinafter, this stay is designated by the same reference numeral as the outer layer 2). A lock device 30 is provided in the. The locking device 30 includes an engagement holding portion 31 and a support cylinder 32 which is arranged inside the backrest portion 20 and into which the headrest stay 2 is inserted. The engagement holding portion 31 includes a housing 33 that surrounds the stay 2 of the headrest 21, and an engagement plate 3 that is housed in the housing 33 so as to be displaceable in a direction perpendicular to the axis of the stay 2 and that allows the stay 2 to pass through.
4 and a spring 35 for urging the engagement plate 34 in the engagement direction with the engagement portion 3 of the stay 2. Therefore, from the viewpoint of operability, when the headrest 21 is moved up and down, the engagement plate 34 is pressed in a direction against the spring 35, so that the edge 37 located in the locking hole 36 is removed from the engagement portion 3 and the stay 2 is moved. Is designed to move up and down. Also,
An operation piece 38 for removing the side edge 37 from the engagement portion 3 is attached to the engagement plate 34.

As the locking means of the stay 2, in addition to the example shown in FIG. 3, for example, at least one side surface of the stay 2 is formed with a tapered portion or a continuous uneven portion or both of which approach the axis as it goes downward. A support cylinder for guiding the vertical movement of the stay 2 is disposed inside the backrest portion 20, and a casing is formed on the upper portion of the support cylinder. An engaging member having a corrugated engaging surface that press-engages with the mating portion 3 is rotatably attached, and a knob portion of the engaging member protruding to the outside of the casing is always biased upward by a spring. It is also possible to use the device 30.

To fix the stay 2 thus constructed to the plastic core 21A of the headrest 21,
As shown in FIG. 4, using split molds 40 and 41 for hollow molding, a resin plate 42 that is softened by heating on the inner wall of the split mold 40.
And the resin plate 42 is brought into contact with the stay 2 so that the lower end side of the stay 2 is projected downward. On the inner wall of the other split mold 41, a mold pressing portion 43 is provided so as to face the stay 2, and
The beat portion 44 is formed at a desired position on the inner wall of the split molds 40 and 41. These mold pressing portion 43 and beat portion 44
Will form a bottomed hole and an uneven portion when the hollow molded product is completed. When the resin plate 42 and the stay 2 are set in the split mold 40 in this way, a material plasticized by a die 45 of a molding machine (not shown), that is, a pipe-like shape having a desired thickness and diameter in advance is used. The parison 46 is extruded to an appropriate length between the split molds 40 and 41. Parison 4
When 6 is extruded, the split molds 40 and 41 are clamped to sandwich the parison 46, and compressed air is blown into the parison 46 from the nozzle 47 to sandwich the stay 2 between the parison 46 and the resin plate 42. The parison 46 sandwiching the stay 2 and the resin plate 42 are fused to cover the entire outer peripheral surface of the stay 2 with a resin material having a uniform thickness. At this time, the outer layer 2 of the stay
Since it is also made of a plastic material, this outer layer 2 also fuses with the parison 46 and the resin plate 42. Therefore, the fixation becomes strong. FIG. 5 shows a core body 21A of the headrest 21 to which the stay 2 is fixed by the method shown in FIG.

The fixing means for fixing the stay 2 and the core body 21A is formed by forming uneven portions and screw portions for adhesion on the outer layer 2 of the stay without using the resin plate 42 and molding the core. It is also possible to increase the adhesive strength with the body 21A. Alternatively, the core body 21A may be separately molded, and then the stay 2 and the core body 21A may be ultrasonically welded.

The plastic material that can be preferably used as the outer layer 2 of the stay is 6.6 nylon and 7 mm.
The material mixed with the glass fiber can be more preferably used, and the outer layer 2 formed of such a material has improved friction resistance.

[0015]

As described above, according to the present invention, the metal core material is covered with the plastic material to form the outer layer, and the engaging portion is formed on the outer layer. It is much lighter in weight and has strength comparable to metal rods. Further, since the core material is covered with the plastic material, rust prevention treatment is unnecessary and post-processing for forming the engagement portion is also unnecessary. Further, when the core body of the headrest is formed of a plastic material, the adhesion to the core body is made of the plastic materials, so that it becomes easy and strong. Further, in the case where the plastic material forming the outer layer is mixed with the reinforcing fiber such as glass fiber, the strength can be further improved. Further, in order to achieve fashion, bright coloring can be easily performed by mixing a coloring agent into the plastic material forming the outer layer. Furthermore, when the core material is formed of a pipe-shaped member and the thickness of the outer layer is 2 to 4 times larger than the thickness of the core material, both weight reduction and strength can be sufficiently satisfied.

[Brief description of drawings]

FIG. 1 is a sectional view showing a preferred embodiment of the present invention.

FIG. 2 is a sectional view showing an example of molding means.

FIG. 3 is a perspective view showing a state in which the headrest is fixed and is inserted into a backrest portion.

FIG. 4 is a cross-sectional view showing an example of means for fixing the stay when molding the core body of the headrest.

FIG. 5 is a perspective view showing a state where a stay is fixed to a core body.

[Explanation of symbols]

 1 core 2 outer layer 3 engaging part

Claims (4)

[Claims] 1. A headrest stay characterized in that a metal core material is covered with a plastic material to form an outer layer, and an engaging portion is formed on the outer layer. 2. The headrest stay according to claim 1, wherein a reinforcing fiber such as glass fiber is mixed in the plastic material forming the outer layer. 3. The headrest stay according to claim 1, wherein a colorant is mixed in the plastic material forming the outer layer. 4. The core material is formed of a pipe-shaped member, and the thickness of the outer layer is 2 to 4 times greater than the thickness of the core material. The listed headrest stay.