JP3080299B2 - Core material for automotive interior parts and molding device therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core material for an interior part such as a door trim, a rear side trim or a pillar trim for an automobile, and a molding apparatus therefor. The present invention relates to a core material for an automobile interior part capable of absorbing collision energy and a molding device therefor.

[0002]

2. Description of the Related Art Many interior parts for automobiles are formed by attaching a skin material to the surface of a core material. The molding of the automobile interior parts and the core material is performed by injection of a synthetic resin material and press molding as a rationalization measure for the purpose of reducing the number of parts and man-hours.

[0003] The molding of the core material of the automotive interior parts includes:
A molding device 10 as shown in FIG. 9 is applied. The molding apparatus 10 includes a lower mold 13 having a mold surface 14 corresponding to an outer shape of an interior part of an automobile, for example, the core material 2 of the door trim 1,
An upper mold 11 having a mold surface 12 corresponding to the lower mold 13 is provided. The lower mold 13 supplies a plurality of gates 15 opening to the mold surface 14 and is connected to the gate 15 to supply the molten synthetic resin 4. A runner 17 is formed.

In the molding apparatus 10, the skin material 3 is disposed between the upper mold 11 and the lower mold 13, and the molten synthetic resin 4 is passed from a gate 15 through a runner 17 at a predetermined position of the upper mold 11. It is supplied (injected) to the mold surface 14 of the lower mold 13. After or before the end of the injection of the molten synthetic resin 4, the upper mold 11 is further lowered to close the mold, and the molten synthetic resin 4 is pressure-formed together with the skin material 3. Thus, the door trim 1 having a predetermined shape in which the molten synthetic resin 4 forms the core material 2 and the core material 2 and the skin material 3 are integrally bonded is obtained.

Further, in order to protect an occupant during a side collision of an automobile, various means have been developed for the interior part 1 for an automobile to absorb the impact energy when the occupant's chest and waist come into contact with each other.

For example, Japanese Unexamined Utility Model Publication No. Hei 6-78037 discloses, as shown in FIGS. 10 and 11, an area 8 in which an occupant abuts against a core member 2 at the rear of a door trim 1 as an interior part for an automobile at the time of a side collision. There is disclosed a technique in which a plurality of weld lines 6 running inside and outside of the vehicle are formed.

In the molding apparatus 10 shown in FIG. 9, the weld line 6 is provided with at least three or more gates 15 on the mold surface 14 of the lower mold 13 corresponding to the vicinity of the area 8 where the occupant abuts. The gate 15 is formed by providing an adjusting mechanism 16 for adjusting the resin injection amount. That is, by adjusting the injection amount of the resin from the gate 15 by the adjusting mechanism 16 when the molten synthetic resin 4 is injected, the weld line 6 as shown in FIGS. 10 and 11 is generated at an intermediate position of the gate 15. You.

The weld line 6 is connected to an adjacent gate 15.
The boundary formed at the portion where the molten synthetic resin 4 injected into the molding dies 11 and 13 from each other collides, and where the weld line 6 is generated has a lower mechanical strength than the remaining portion. . Therefore, by generating a weld line 6 running inside and outside the area 8 where the occupant abuts on the core member 2 of the vehicle door trim 1, the core member 2 of the door trim 1 starts from the weld line 6 at the time of a side collision of the vehicle. It will destroy it, which will absorb the impact energy and protect the occupants.

[0009]

However, in the above-mentioned conventional example, the gate 15 is set according to the desired number of weld lines 6 and the desired position of the weld lines 6 and the molten synthetic resin 4 is formed.
It is necessary to adjust the injection amount. Therefore, a mold (upper and lower dies 11, 13) corresponding to the generation of the weld line 6 having the desired performance is required, so that not only the structure of the mold is complicated, but also the injection amount of each gate 15 is adjusted. The adjusting mechanism 16 for performing the adjustment is complicated. As a result, the structure of the mold may be complicated and expensive, and it may be difficult to obtain the core material 2 having the desired weld line 6.

The present invention has been devised in view of the above-mentioned conventional circumstances, and has a simple structure of a molding die and can easily obtain a core material having desired performance. And a molding device therefor.

[0011]

In order to achieve the above object, according to the present invention, a molten synthetic resin is formed by injecting a molten synthetic resin into a molding die from a plurality of gates opened in the molding die. In the core material of the automotive interior part, a plurality of protrusions provided near the periphery of the gate opening partially deflect the flow of the molten synthetic resin in a range where the occupant comes into contact with the automobile interior part in a side collision. A weld line generated by the above is set.

The invention according to claim 2 is a molding apparatus for molding a core material of an interior part for an automobile by injecting a molten synthetic resin into the molding die from a gate opening in the molding die. The gate is opened in a molding die corresponding to an area where an occupant comes in contact at the time of a side collision, and a plurality of projections are provided near the periphery of the opening of the gate, and the projections partially deflect the flow of the molten synthetic resin. Thus, a weld line is generated downstream of the projection.

Further, the invention according to claim 3 is configured such that the projection of the structure according to claim 2 is provided so as to be able to protrude and retract from the mold.

In the present invention, the plurality of protrusions provided in the vicinity of the periphery of the gate opening can be achieved by pins of a predetermined size, shape and number provided on a molding die. Also,
The protrusions can be provided so as to be able to protrude and retract from the molding die. In this case, formation of traces of the protrusions on the core material is advantageously prevented.

At the time of molding the interior part, the molten synthetic resin injected from the gate opening into the mold is filled into the mold by injection pressure and mold clamping. At this time, the flow of the molten synthetic resin is partially deflected by the projections and separated, and then meets again downstream of the projections, and the molten synthetic resins collide with each other at the meeting portion to generate a weld line.

The weld line has a set position of a protrusion,
By changing the shape, size, set number, and the like, the state of generation can be changed, so that the amount of absorbed energy at the time of a side collision can be easily changed.
Thus, a core material having desired performance (absorbed energy) can be easily obtained.

Therefore, a core material for an automobile interior part and a molding device thereof having a simple structure and an expected performance can be easily obtained.

[0018]

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

FIG. 1 is a plan view of a door trim as an automobile interior part to which the core material of the present invention is applied. 1 in the figure
Is a car door trim (hereinafter referred to as door trim).
The door trim 1 is obtained by injecting and press-molding a thermoplastic resin.
Are integrally bonded. Further, the door trim 1 is provided with a measure for absorbing impact energy in order to protect an occupant from an impact in the event of a side collision of an automobile. Specifically, as shown in FIG. 1, a plurality of weld lines 6 are set on the core material 2 in a range (hatched portion) 8 where the occupant's chest and waist come into contact with the rear part of the door trim 1, and the core material is provided at the time of side collision. 2 is capable of absorbing impact energy by breaking the weld line 6 as a starting point.

As described later in detail, the weld line 6 is provided with a plurality of projections near the periphery of an opening of a gate for injecting the molten synthetic resin into a molding die, and the projections partially flow the molten synthetic resin. It is generated by deflecting.

The door trim 1 can be formed by a forming apparatus 10 shown in FIG. The molding apparatus 10 includes a lower mold 13 having a mold surface 14 corresponding to the outer shape of the core member 2 of the door trim 1 facing the upper mold (not shown). One or more gates 15 for injecting the molten synthetic resin 4 are provided, and a runner 17 for supplying the molten synthetic resin 4 is connected to the gate 15. In addition, some of the gates 15 have a mold surface 1 of the lower mold 13 at a position corresponding to the area 8 where the occupant abuts during a side collision.
4 and a plurality of pins (projections) 18 are provided near the periphery of the opening of the gate 15.

The door trim 1 is formed as follows. That is, the skin material 3 is placed between the upper mold and the lower mold 13 (not shown).
Place. Thereafter, the upper mold (not shown) is lowered and temporarily stopped at a predetermined position, and the molten synthetic resin 4 is injected into a molding die between the upper mold (not shown) and the lower mold 13. Specifically, in this embodiment, the molten synthetic resin 4 is injected from the gate 15 onto the mold surface 14 of the lower mold 13 via the runner 17. Before or after the injection of the molten synthetic resin 4, the upper mold (not shown) is further lowered to close the mold, thereby forming the synthetic resin core 2, and the core 2 and the skin 3 are integrated. To obtain a door trim 1 of a predetermined shape attached to the door trim.

The molten synthetic resin 4 injected into the mold
Flows as follows. That is, as shown in FIGS. 3 and 4, the injected molten synthetic resin 4 flows concentrically from the gate 15 while expanding its area by the injection pressure and the mold clamping (pressing of the upper mold), and the molding die Is satisfied within. At this time, the flow of the molten synthetic resin 4 is partially deflected by a pin 18 provided in the vicinity of the periphery of the opening of the gate 15 and separates in two directions. The molten synthetic resin collides with the portion (see FIG. 4). As a result, the weld line 6 is generated downstream of the pin 18. At the same time,
A recess 7 is formed in the core 2 at the position of the pin 18 (see FIG. 3).

The set position, shape, size, set number, etc. of the pins 18 are arbitrarily set according to the position of the gate 15, molding conditions, the required position for forming the weld line 6, and the mechanical strength of the weld line 6. be able to. For example,
As shown in FIG. 1, if the pins 18 are set in the Z direction and the Y direction with respect to the gate 15, the weld line 6 along the Z direction and the Y direction can be generated.

As shown in FIG. 3, the height h of the pin 18 is determined in relation to the thickness t of the core 2 of the door trim 1, and the thickness t of the core 2 is 2 to 4 mm. In this case, it is desirable that the height h of the pin 18 is also set to 2 to 4 mm within a range that does not affect the appearance of the skin material 3. Also, pin 1
The diameter d of the recess 8 is
Does not affect the appearance and product strength of the skin material 3 and has a sufficient strength when the molten synthetic resin 4 flows, and a size of 1 to 5 mm is preferably selected.

Further, the shape of the pin 18 may be cylindrical or rib-like. In particular, when the pin 18 is set in a rib shape, the concave portion 7 formed in the core material 2 has a groove shape. This groove shape is a shape in which stress tends to concentrate at the time of a side collision of the vehicle. It becomes the starting point of crack 2 and enhances the effect of absorbing collision energy.

As shown in FIG. 5, by increasing the set number of pins 18 and increasing the number of locations where the weld line 6 is generated, it is possible to change the ability to absorb the collision energy.

Further, as shown in FIG. 6, a slit 18a is formed at the tip of the pin 18, and the slit 18a is arranged substantially in line with the flow direction of the molten synthetic resin 4, so that the pin 18 Including synthetic resin 4
Is divided in three directions, so that the weld line 6 can be generated more reliably.

As described above, the pin 18 is provided near the periphery of the opening of the gate 15, and the weld line 6 generated by the pin 18 can be set at a predetermined position of the door trim 1. Further, the molding die may be provided with a pin 18 in the vicinity of the opening periphery of the gate 15, so that the structure of the molding die can be simplified, the molding die cost can be reduced, and the maintenance man-hour and cost of the molding die can be reduced. Durability is improved.

FIG. 7 is a drawing showing another embodiment of the present invention. This embodiment differs from the above-described embodiment in that the pin 18 is provided so as to be able to protrude and retract from the lower mold 13. Specifically, the hydraulic cylinder 1 is
9 is attached.

According to such a configuration, after the molten synthetic resin 4 is injected from the gate 15 and pressurized by the upper die (not shown), the weld line 6 is generated on the downstream side of the pin 18. Before the molten synthetic resin 4 is filled in the entire mold, the pin 18 is lowered by the hydraulic cylinder 19. By lowering the pin 18 so that its tip is flush with the mold surface 14 of the lower mold 13, the recess 7 formed by the pin 18 formed in the above embodiment is formed inside the core 2. It is not formed.

Therefore, since no concave portion is formed in the core material 2, the appearance quality of the surface of the skin material 3 can be improved without causing shrinkage or the like on the surface of the core material 2.

Instead of the hydraulic cylinder 19, as shown in FIG. 8, a spring 20 having a predetermined spring force may be provided, and the pin 18 may be provided so as to be able to protrude and retract from the lower mold 13. With such a configuration, the same operation and effect as described above can be obtained.

[0034]

As described above, according to the present invention, according to the present invention, a pin is provided near the periphery of an opening of a gate, and a weld line generated by the pin is set at a designated position of an automobile interior part. be able to. Also, the mold may be provided with pins near the periphery of the gate opening, so that the mold structure can be simplified and the mold cost reduced, and the maintenance man-hour and cost of the mold can be reduced and the durability can be improved. It is planned.

[Brief description of the drawings]

FIG. 1 is a plan view of an automobile door trim to which a core material of an interior part according to the present invention is applied.

FIG. 2 is a partial cross-sectional view of the molding apparatus for the vehicle door trim.

FIG. 3 is an enlarged view of a main part of the molding apparatus for a vehicle door trim.

FIG. 4 is a view illustrating a flow state of a molten synthetic resin.

FIG. 5 is a diagram for explaining a pin arrangement state, and is an explanatory view showing a state where the pins are arranged concentrically with respect to a gate (a) and a state where the pins are arranged at unequal intervals (b).

FIG. 6 is a view showing another embodiment of the pin, and is a perspective view (a) and a drawing (b) for explaining a flow state of the molten synthetic resin.
It is.

FIG. 7 is a partial cross-sectional view of a molding apparatus according to another embodiment of the present invention, showing a state where molten synthetic resin is injected into a molding die (a) and a state where the mold is clamped (b).

FIG. 8 is a partial cross-sectional view of a molding apparatus showing still another embodiment of the present invention.

FIG. 9 is a cross-sectional view of a conventional automobile door trim molding apparatus.

FIG. 10 is a perspective view of an automobile door trim formed by a conventional forming apparatus.

FIG. 11 is a perspective view of another automotive door trim formed by the molding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automobile door trim (interior parts) 2 Core material 4 Molten synthetic resin 6 Weld line 8 Range of contact 10 Molding device 11 Upper mold (mold) 13 Lower mold (mold) 18 Pin (projection)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B60J 5/00 B29C 45/26 B60R 13/02 B60R 21/02

Claims (3)

(57) [Claims] 1. A core material for an automobile interior part formed by injecting a molten synthetic resin into the molding die from a gate opening into the molding die, wherein
A weld line formed by a plurality of projections provided near the periphery of the gate opening partially deflecting the flow of the molten synthetic resin is set in a range where an occupant abuts during a side collision. Core material for automotive interior parts. 2. A molding apparatus for molding a core material of an automobile interior part by injecting a molten synthetic resin into a molding die from a gate opening into the molding die, wherein an occupant can move the gate when a side collision occurs. Along with the opening in the mold corresponding to the area of contact, a plurality of projections are provided in the vicinity of the periphery of the opening of the gate, and the projections partially deflect the flow of the molten synthetic resin, thereby downstream of the projections An apparatus for forming a core material for an automobile interior part, wherein a weld line is generated. 3. The apparatus for molding a core material of an automobile interior part according to claim 2, wherein the plurality of projections are provided so as to be able to protrude and retract from the molding die.