JPH1029466A - Luggage box - Google Patents

Abstract

(57) [Summary] A luggage box that is placed and stored in a trunk room of an automobile to absorb the impact energy in the event of a collision and prevent the body frame from being deformed. The luggage box is lightweight and has sufficient energy absorption performance. A luggage box (1) has a density of 0.06-0.
A rib 3 having a T-shaped structure is provided in the storage part 2 in the box 1 entirely or at least partially. The rib 3 is made of a molded article of expanded polypropylene resin particles of 30 g / cm ^3. To a plurality of storage compartments 2a, 2
a, ...

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a luggage box which is placed and stored in a trunk room of an automobile.

[0002]

2. Description of the Related Art In recent years,
As the performance of automobiles has become higher, the safety design of the body structure has become more important. Above all, by absorbing the impact energy in the event of a collision and preventing the body frame from deforming, the occupant's habitat during a collision Attention has been focused on vehicle body structures that can maintain space.

[0003] In a general automobile, an engine room is formed in the front part, and an engine is mounted inside the engine room. Therefore, in the case of a forward collision, a certain energy absorbing effect can be expected, and the vehicle body structure in the occupant's living space is relatively unlikely to be deformed during the collision.

On the other hand, in the case of a rear collision, the trunk room formed at the rear of the automobile has a hollow structure, so that the energy absorption effect obtained in the case of a front collision cannot be expected. Often, the body structure of the occupant's living space is deformed by the impact of the vehicle. In particular, 1BO
In a car called an X car or a 2BOX car, there is no clear partition between a passenger's living space and a trunk room, and it is structurally difficult to make the rear structure resistant to impact.

[0005] Looking at the internal structure of the trunk room, the bottom of the trunk is usually a trunk in which a core material such as a wooden plywood, an insulation board, a cardboard, a synthetic resin plate, or an FRP plate is covered with a surface material such as a nonwoven fabric. Floor boards are laid. Some commercial vehicles also have a luggage box that stores tools in a trunk room.

[0006] However, even if the above-mentioned plate is laid on the bottom of the trunk room, it is not possible to expect sufficient energy absorbing performance to absorb the impact energy at the time of collision with this plate.

On the other hand, when the luggage box is placed and stored in the luggage compartment, since the luggage box has a box structure, an energy absorbing effect cannot be expected depending on the position where the luggage box is placed. The luggage box is an injection-molded product or an injection blow-molded product. In order to sufficiently absorb the impact at the time of collision, it is necessary to increase the thickness of the luggage box to increase its rigidity. For this reason, if the luggage box is provided with energy absorption performance, the weight will inevitably increase, and the increase in the weight of the luggage box not only makes it inconvenient to handle, but also increases the weight of the vehicle body and leads to a reduction in fuel consumption. There are also problems.

When the luggage box is placed and stored in the luggage compartment, the luggage box generates an unusual sound in resonance with vibrations during traveling, and the generated unusual sound is amplified as a bat sound in the luggage box. There is a problem that it is done, and it is necessary to take measures for this. It is also possible to put a steel plate on the luggage box, put lead in the luggage box lid, and even the main body, etc. to suppress the luggage box vibration, so that no noise is generated. However, if such a measure is taken, the weight of the luggage box increases.

In view of the above problems, the present inventors have attempted to reduce the weight of a luggage box placed and stored in a trunk room in order to strengthen the body structure of an automobile.
As a result of intensive research to provide a luggage box with sufficient energy absorption performance while being lightweight,
The present invention has been completed.

[0010]

That is, a luggage box according to the present invention is a luggage box to be placed and stored in a trunk room of an automobile, and the luggage box is made of a polypropylene-based luggage having a density of 0.06 to 0.30 g / cm ³ . It is made of a resin foam particle molded body, and the storage part in the box is entirely or at least partially partitioned into a plurality of storage sections by a T-shaped rib.

Further, the luggage box of the present invention has a density ρ (g / cm ³ ) of a molded article of expanded polypropylene resin particles.
And the energy absorption E ₂₀ (kg · cm / cm ³ ) at 50% compression of the molded body at 20 ° C. preferably has a relationship represented by the following formula (1). E ₂₀ / ρ ≧ 45 (kg · cm / g) (1)

In the present invention, the molded article of expanded polypropylene resin particles has an average particle size of 1.0 to 7.0 mm,
It is preferable that foamed particles having an average cell diameter of 100 to 350 μm and a closed cell ratio of 90% or more are formed in a mold.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A luggage box according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of the luggage box of the present invention. FIG. 2 is a perspective view showing another example of the luggage box of the present invention, and FIG. 3 is a plan view showing still another example.

In the luggage box 1 of the present invention, the storage part 2 in the box 1 is provided with a rib 3 having a T-shaped structure in whole or at least a part.
Are partitioned into a plurality of storage sections 2a, 2a,....

"Rib having a T-shaped structure as a whole" in the present invention
Means a rib 3 extending from one of the opposed inner walls to the other in the luggage box 1 as shown in FIG.
a, and a rib having a flat T-shape constituted by a rib 3b intersecting at a right angle thereto.

On the other hand, "at least a part of the rib having a T-shaped structure" means that at least a part of the rib 3 has a T-shaped structure. For example, as shown in FIG. It refers to a rib whose structure includes a portion having a T-shaped structure as described above. Therefore,
The “ribs having at least a part of a T-shaped structure” in the present invention includes those having the embodiments shown in FIGS. 3 (a), 3 (b) and 3 (c). In these embodiments, for example, the hatched portion in the drawing has a T-shaped structure.

The ribs 3 as described above are preferably formed integrally in the luggage box 1 by an in-mold molding method as described later. In the present invention, the ribs 3 are formed separately from the luggage box 1. However, this can be joined to the luggage box 1 by an appropriate means.

Further, in the present invention, as shown in FIG. 4, for example, a notch groove 7a is provided at a predetermined position of the rib 3a, and a notch groove 7b is formed on the inner wall of the box 1 opposed thereto.
May be provided, and the rib 3 may be configured by detachably attaching the rib constituting piece 3c between the notch grooves 7a and 7b.

When the ribs 3 are configured as described above, the way of partitioning the storage compartments 2a, 2a,... Can be appropriately changed according to the shape and size of the storage items stored in the luggage box 1. When the present invention is carried out in such a mode, the rib 3a composed of the rib 3a and the rib component piece 3c is also used.
May have a T-shaped structure. In the embodiment shown in FIG. 4, for example, a portion surrounded by a dashed line in the drawing has a T-shaped structure.

In the present invention, the rib 3 provided in the storage portion 2 in the box 1 has a T-shaped structure as a whole or at least a part thereof.
Not only partition the storage section 2 into a plurality of storage sections 2a, 2a,..., But also have a role as a reinforcing material for imparting energy absorption performance to the luggage box 1 of the present invention.

According to the present invention, the luggage box 1 is formed of a specific molded article of expanded polypropylene resin particles as described later, and the rib 3 provided in the storage portion 2 in the box 1 is provided.
By making the whole or at least a part of the shape of the T-shaped structure, the luggage box 1 can be reduced in weight and the luggage box 1 can have excellent energy absorption performance.

The luggage box 1 is made to have more excellent energy absorption performance in consideration of the storability of the storage items in the luggage box 1 and the lightness of the box 1 and the action of the rib 3 as a reinforcing material. The area of the rib 3 occupying the entire area of the luggage box 1 when the luggage box 1 is viewed from a plane (for example, in the case of the embodiment shown in FIG. The area ratio is preferably 3 to 6%, and the thickness of the rib 3 is preferably 6 to 20 mm.

In the example shown here, the luggage box 1 has a rectangular parallelepiped shape for convenience.
The shape of the luggage box 1 of the present invention is not limited to a rectangular parallelepiped, and the shape can be arbitrarily changed according to the structure of the trunk room and the position where the luggage box 1 is placed and stored.

That is, in general, the trunk room of the automobile has a complicated structure such as a tire house protruding or a spare tire stored therein, and the structure varies depending on the vehicle type. The luggage box 1 of the present invention is placed and stored in the trunk room of an automobile, for example, at the bottom of the trunk room 9 as shown in FIGS. The shape of the luggage box 1 can be appropriately selected according to the structure of the trunk room 7 and the position where the luggage box 1 is placed and stored so that the luggage box 1 can be easily stored. However,
In order to obtain sufficient energy absorption performance, the luggage box 1 preferably has a thickness of 6 to 20 mm. In the figure, 8 is a car, 10 is a spare tire, 11 is a bumper, 1
Reference numeral 2 denotes a seat.

If the luggage box 1 of the present invention is placed and stored in the luggage compartment of the vehicle as described above, the impact energy at the time of a rear collision is absorbed by the luggage box 1, thereby strengthening the rear structure of the vehicle. it can. Although some commercial vehicles have a trunk room in the front part, the luggage box 1 of the present invention
Is also applicable to such vehicles, in which case the front structure of the vehicle is reinforced.

The luggage box 1 of the present invention may be configured so as to be mounted and stored over the entire bottom surface of the trunk room, and to be mounted and stored on a part of the bottom surface of the trunk room (for example, above a spare tire). However, when the luggage box 1 is placed and stored in a luggage compartment, the ribs 3 provided in the box 1 form a T-shaped structure. The portion extending from one inner wall to the other inner wall (the rib 3a corresponds to the example shown in FIG. 1 as an example) is located parallel to the bumper of the automobile. preferable. If the luggage box of the present invention is configured in this way, the ribs 3 effectively act as a reinforcing material, and the energy absorption performance of the luggage box 1 is maximized.

Furthermore, the luggage box 1 of the present invention is preferably used as a luggage box 1 with a lid, in combination with a lid 4 made of the same material as the box 1. In this case, the lid 4 serves not only as a cover for covering the upper surface of the luggage box 1 but also as a structural material for improving the energy absorbing performance of the luggage box 1. Therefore, by using such a lid 4 in combination with the luggage box 1 (that is, covering the upper surface of the luggage box 1 with the lid 4 and placing it in a trunk room), the energy absorption performance of the luggage box 1 Can be made more excellent.

A reinforcing rib 5 can be provided on the front side and / or the back side of the lid 4. The specific form of the ribs provided on the lid 4 is not particularly limited. For example, even if the ribs are provided in a discontinuous lattice shape as in the lid 4 shown in FIG.
It may be provided in a continuous lattice shape as shown in FIG. 6D, or a cross-shaped independent rib 5 as shown in FIG.
.. May be provided in a scattered manner.

By providing such a rib 5 on the lid 4, not only can the luggage box 1 be improved in strength against impact from a horizontal direction when the luggage box 1 is placed and stored in a trunk room, but also can be improved in a vertical direction. Can be improved, and the cover 4 can be prevented from bending when, for example, a load is placed on the cover 4 or when a person gets on the cover.

When the ribs 5 are provided on the back surface side of the lid 4, the ribs 5 provided on the lid 4 as shown in FIGS.
The ribs 4 provided on the luggage box 1 and the inner walls of the luggage box 1 are fitted to prevent the lid 4 from shifting. FIG. 5 shows the example shown in FIG.
FIG. 5 is a sectional view taken along line VV of a state in which the upper surface of the luggage box 1 is covered with a lid 4.

When the luggage box 1 is placed in the luggage compartment and is not used in combination with the lid 4, the upper surface of the luggage box may be covered with a conventional trunk floor plate.
The lid 4 can also be configured to also serve as a trunk room floor plate, and the lid 4 may be larger than the luggage box. Further, the luggage box 1 and the lid 4 can be subjected to graining on the surface for decoration, or can be laminated with a skin material such as a nonwoven fabric, a felt, and a woven fabric.

The luggage box 1 of the present invention is, for example, a so-called in-mold molding method in which after foamed polypropylene resin particles are filled in a molding die, the foamed particles are heated with steam or the like to fuse the particles together. It is composed of a molded article of expanded polypropylene resin particles obtained by the method. The lid 4 is also made of a molded article of expanded polypropylene resin particles similar to the luggage box 1. When the rib 3 is formed separately from the luggage box 1 as described above, or when the rib component 3c is configured to be detachably attached to the luggage box 1, the rib 3 and the rib component 3c are It is preferred to be composed of a polypropylene resin foam.

As the polypropylene resin, polypropylene, propylene-ethylene copolymer, propylene-
Butene copolymer, propylene-ethylene-butene copolymer and the like are exemplified, among these, polypropylene,
A propylene-butene copolymer is preferred. Other components can be copolymerized or blended with these polypropylene resins as needed as long as the effects of the present invention are not impaired. The polypropylene resin may be cross-linked or non-cross-linked, but non-cross-linked is particularly preferable.

The expanded polypropylene resin particles are prepared, for example, by dispersing propylene-based resin particles in pellet form and a foaming agent in a dispersion medium such as water in a closed container and heating the resin particles to a temperature above the softening temperature. After impregnating the resin particles with a foaming agent, one end of the container is opened, and the resin particles and the dispersion medium are discharged from the container under a low-pressure atmosphere (usually under atmospheric pressure) to foam the resin particles. can get.

The foamed polypropylene resin particles constituting the luggage box 1 of the present invention may be made of such a foamed polypropylene resin particle as necessary, if necessary, with an inorganic gas such as air, oxygen, nitrogen, carbon dioxide or the like. And pressurized with a mixed gas of a volatile blowing agent such as hexane, heptane, 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, etc.
After applying an internal pressure of about kg / cm ² (G), the foamed particles are filled in a mold of a desired shape,
The particles can be produced by foaming and expanding the particles with steam of about cm ² (G) and fusing the particles to each other.

In the present invention, the molded body has a density ρ of 0.06 to 0.30 g / cm ³ , preferably 0.1 to 0.30 g / cm ³ .
075 to 0.20 g / cm ³ is used. If the density ρ exceeds the above range, the weight increases and the luggage box 1 cannot be reduced in weight. On the other hand, if the density ρ is less than the above range, sufficient energy absorption performance cannot be obtained,
In order to ensure the desired energy absorption performance, the luggage box 1 must be made thicker. As a result, the weight of the luggage box 1 increases, so that the luggage box 1 cannot be reduced in weight. By setting the density ρ in the above range, the sound insulation of the luggage box 1 is also improved.

The molded body has a density ρ and a density of 2
Energy absorption at the time of 50% compression at 0 ° C. E ₂₀ (k
g · cm / cm ³ ), preferably E ₂₀ / ρ ≧ 45 kg · cm / g (1) Preferably, E ₂₀ / ρ ≧ 50 kg · cm / g Is preferred.

Between the density ρ and the energy absorption E ₂₀ (kg · cm / cm ³ ) at 50% compression at 20 ° C.,
By configuring the luggage box 1 of the present invention from a molded article of expanded polypropylene resin particles in which the above relationship is satisfied, the energy absorption rate per unit weight of the luggage box 1 can be increased, and the luggage box 1 is lighter and more energy absorbing. The luggage box 1 is excellent in quality.

The energy absorption amount E _{20 of the} molded article of expanded polypropylene resin particles at 50 ° C. at 50 ° C.
(Kg · cm / cm ³ ) was measured using a test piece having a length of 50 mm, a width of 50 mm, and a thickness of 25 mm cut out from the molded body.
In a compression strain-compression stress curve at 20 ° C. obtained by performing a compression test on the test piece in accordance with JIS Z0234 A method, the area up to the point where the compression strain becomes 50% (the hatched line in FIG. 9) Part).
FIG. 9 is a compression strain-compression stress curve of the expanded polypropylene resin particles having a density of 0.127 g / cm ^{3 in} the compression test.

The molded article of expanded polypropylene resin particles is
In order to have the (1) the relationship between the amount of energy absorption E ₂₀ 50% during the compression of the density ρ and 20 ° C., as the propylene-based resin foamed particles, for example, close to the spherical shape, average particle size 1 0.0 to 7.0 mm, preferably 1.5
The molded body may be manufactured by the above-described in-mold molding method using a material having a diameter of about 3.5 mm, an average cell diameter of 100 to 350 μm, preferably 120 to 300 μm, and a closed cell ratio of 90% or more.

[0041]

As described above, the luggage box of the present invention is made of a molded article of expanded polypropylene resin particles having a density of 0.06 to 0.30 g / cm ³ , and the storage part in the box is entirely or at least partially T-shaped. Since it is divided into a plurality of storage compartments by the ribs of the letter-shaped structure, it has sufficient energy absorption performance, so if the luggage box is placed and stored in the trunk of the car, the rear structure of the car will be strengthened Can be achieved. In addition, since the luggage box of the present invention having the above structure is lightweight, it can be easily taken out of the luggage compartment and the like, and is easy to handle, and does not cause a reduction in fuel efficiency. In addition, there is no noise generated from the luggage box in resonance with the vibration during running, and the sound insulation is excellent.

Further, the molded article of the expanded polypropylene resin particles constituting the luggage box is provided with a density ρ of the molded article,
The energy absorption per unit weight of the luggage box is obtained by using a molded body having a specific relationship with the energy absorption amount E ₂₀ (kg · cm / cm ³ ) at 50% compression at 20 ° C. Rate can be higher,
A luggage box that is lighter and has excellent energy absorption performance can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a luggage box of the present invention.

FIG. 2 is a perspective view showing another example of the luggage box of the present invention.

FIG. 3 is a plan view showing another example of the luggage box of the present invention.

FIG. 4 is a perspective view showing another example of the luggage box of the present invention.

FIG. 5 is a sectional view taken along line VV of the example shown in FIG. 1 in a state where the upper surface of the luggage box is covered with a lid.

FIG. 6 is a plan view showing an example of a lid.

FIG. 7 is a schematic view showing a state in which the luggage box of the present invention is placed and stored in a trunk room.

FIG. 8 is a schematic view showing a state where the luggage box of the present invention is placed and stored in a trunk room.

FIG. 9 is a compression strain-compression stress curve in a compression test of a test piece cut from a molded article of expanded polypropylene resin particles.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Luggage box 2 Storage section 2a Storage section 3 Rib 8 Car 9 Trunk room

Claims (3)

[Claims] 1. A luggage box mounted and stored in a trunk room of an automobile, wherein the luggage box is formed of a foamed polypropylene resin particle having a density of 0.06 to 0.30 g / cm ³ and stored in the box. A luggage box, wherein the whole or at least a part of the luggage box is partitioned by a rib having a T-shaped structure into a plurality of storage compartments. 2. The density ρ (g / cm ³ ) of the molded article of expanded polypropylene resin particles, and the density of the molded article at 20 ° C.
% Energy absorption at compression% E ₂₀ (kg · cm / c
2. The luggage box according to claim 1, wherein the luggage box has a relationship represented by the following expression (1) with respect to m ³ ). E ₂₀ / ρ ≧ 45 (kg · cm / g) (1) 3. A molded article of expanded polypropylene resin particles,
Average particle size 1.0-7.0 mm, average bubble diameter 100-35
The luggage box according to claim 1 or 2, wherein foamed particles having 0 µm and a closed cell ratio of 90% or more are formed in a mold.