JP3724916B2 - Method for manufacturing synthetic resin luggage box for motorcycles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to manufacturing method of a motorcycle synthetic resin luggage box.
[0002]
[Prior art]
Conventionally, this type of luggage box has a bottom wall and a peripheral wall integral therewith, and is manufactured by injection molding. Therefore, the whole is fulfilling. Here, “enriched” means dense and does not include a foamed portion or a hollow portion.
[0003]
[Problems to be solved by the invention]
For example, in the scooter type vehicle as a motorcycle, the luggage box is installed in the rear vehicle body, and a lidar seat is also used as the lid. Therefore, the luggage box is lightweight, and its bottom wall is placed directly above the engine, so it has sufficient heat insulation to protect the stored items from thermal effects, and the seat is hinged to the luggage box Therefore, it is required to have sufficient strength.
[0004]
The conventional luggage box has no problem with respect to the strength among the above requirements, but it cannot be said that the light weight and the heat insulation of the bottom wall are sufficient.
[0005]
[Means for Solving the Problems]
The present invention is a lightweight, also includes a bottom wall having an excellent heat insulation and, moreover, an object of the invention to provide the manufacturing method capable steamed amount of the luggage box with sufficient strength.
[0006]
In order to achieve the above object, according to the present invention, a male mold that molds the inner surface side of the luggage box and a female mold that molds the outer surface side of the luggage box are provided, and a gap between the mating surfaces of both molds can be sealed. By preparing a molding die and closing the molding die, a box molding cavity is formed between the male mold and the female mold, and the distance in the mold opening and closing direction in the bottom wall molding region of the cavity is determined by the thickness of the bottom wall. And a step of sealing between the mating surfaces of both molds, and injecting the foamable molding material into the bottom wall molding region and causing the region to flow into the peripheral wall molding region of the cavity. And filling the cavity with at least one of the male mold and the female mold in the mold opening direction so that the distance between the bottom wall forming regions matches the thickness of the bottom wall. A method for producing a synthetic resin luggage box for a motorcycle using the step of foaming the foamable molding material in the mold opening / closing direction intermediate portion of the bottom wall molding region by releasing the seal between the mating surfaces of both molds Is provided.
[0007]
According to such a method, a synthetic resin luggage box for a motorcycle having a bottom wall having a sandwich structure including a foam core layer and a solid skin layer covering the foam core layer and a solid peripheral wall integral with the bottom wall is mass-produced. Is possible. Further, as described above, when the foam core layer is present on the bottom wall, the luggage box is lightened accordingly, and the bottom wall exhibits excellent heat insulation. Furthermore, since the peripheral wall is made of a solid body and the bottom wall has a sandwich structure made of a foam core layer and a solid skin layer, the luggage box has a practically sufficient strength.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, a scooter type vehicle 1 as a motorcycle has a body frame 2, a front wheel 4 that can be steered by a steering handle 3 is supported at a front portion, and a power unit 5 is supported at a rear portion. The power unit 5 includes an engine 6, a transmission mechanism 7, and a rear wheel 8 driven by the engine 6 via the transmission mechanism 7 as usual.
[0009]
In the rear vehicle body 9 covering the vehicle body frame 2 and the power unit 5, a luggage box 10 having an upward opening and capable of containing a relatively large article such as a helmet is installed so as to be positioned directly above the engine 6. A rider seat 11 that also serves as a lid of the box 10 is installed on the rear vehicle body 9.
[0010]
2 to 6, the luggage box 10 is formed of a synthetic resin, for example, polypropylene, and has a bottom wall 14 having a sandwich structure composed of a foam core layer 12 and a solid skin layer 13 covering the foam core layer 12, and the bottom wall 14. And an integral solid peripheral wall 15. In forming the luggage box 10, the mold opening direction a and the mold closing direction b, that is, the mold opening / closing directions a and b are directions intersecting the bottom wall 14.
[0011]
As described above, when the foam core layer 12 is present on the bottom wall 14, the luggage box 10 is lightened accordingly, and the bottom wall 14 exhibits excellent heat insulation. Further, since the peripheral wall 15 is made of a solid body and the bottom wall has a sandwich structure made up of the foam core layer 12 and the solid skin layer 13, the luggage box 10 has a practically sufficient strength.
[0012]
As clearly shown in FIGS. 2 to 5, the bottom wall 14 protrudes downward on the vehicle body front side and extends in the left-right direction of the vehicle body, and on the inner surface side of the hollow protrusion 16. And a pair of existing reinforcing ribs 17. In the bottom wall portion 18 of the hollow convex portion 16, bolt insertion holes 19 are formed on both ends thereof, and a water drain hole 20 is formed between the bolt insertion holes 19. Each reinforcing rib 17 is located close to each bolt insertion hole 19 and inside thereof. Further, the bottom wall 14 has a bulging portion 21 directed upward at the center thereof.
[0013]
On the rear side of the vehicle body of the solid peripheral wall 15, an overhanging portion 22 is provided on the upper portion thereof toward the rear of the vehicle body. The overhanging portion 22 has one bolt insertion hole 23 for mounting a box and a hole 24 for mounting an oil tank inlet. Etc. exist.
[0014]
The luggage box 10 is attached to the vehicle body frame 2 by bolts 25 and 26 respectively inserted into two bolt insertion holes 19 of the bottom wall 14 and one bolt insertion hole 23 of the overhanging portion 22.
[0015]
The seat 11 and the luggage box 10 are hinge-connected to each other on the front side of the vehicle body as follows. That is, as clearly shown in FIGS. 2, 3, and 6, on the vehicle body front side of the solid peripheral wall 15 of the luggage box 10, the hinge half body 27 is connected to the opening end surface 28 of the luggage box 10 and protrudes forward of the vehicle body. A pin hole 30 extending in a direction intersecting the mold opening / closing directions a and b is formed at the tip portion 29. As clearly shown in FIG. 3, the pair of attachment portions 32 of the hinge half body 31 existing on the lower surface of the seat 11 is fitted to the distal end portion 29 of the other hinge half body 27, and each attachment portion 32 and the pin of the distal end portion 29 are pinned. A hinge pin 34 is inserted into the holes 30 and 33 and is prevented from being removed.
[0016]
As a result, the seat 11 is in close contact with the opening end surface 28 of the luggage box 10 at the lying position shown by the solid line in FIG. 1 to close the opening 35 and allow the rider to be seated, while at the standing position shown by the chain line in FIG. The opening 35 of the luggage box 10 is opened. Although not shown in the drawing, a lock mechanism for holding the lying position of the seat 11 is provided between the seat 11 and the luggage box 10.
[0017]
In manufacturing the luggage box 10, the following processes are employed.
[0018]
As shown in FIG. 7, a fixed male mold 36 for mainly molding the inner surface side of the luggage box 10 and a movable female mold 37 for molding mainly the outer surface side of the luggage box 10 are provided. A molding die 41 capable of sealing between the mating surfaces 38 and 39 with a seal member 40 is prepared. Then, by closing the mold 41, a box-forming cavity 42 is formed between the male mold 36 and the female mold 37. In this case, the spaces f, g, and h in the mold opening / closing directions a, b in the bottom wall forming region c, the overhang forming region d, and the hinge half forming region e of the cavity 42 are set to the bottom wall 14, the overhanging portion 22 and the hinge half. The thickness of the solid peripheral wall 15 is set to be smaller than the thickness j, k, m (see FIG. 9) of the body 31, and the interval o in the direction intersecting the mold opening / closing directions a and b in the solid peripheral wall forming region n of the cavity 42 is set. It is set to be substantially the same as p (see FIG. 9), and the space between the mating surfaces 38 and 39 of both molds 36 and 37 is sealed with a seal member 40. A gate 43 communicating with the bottom wall forming region c of the cavity 42 is formed in the male mold 36, and the nozzle 44 communicates with the gate 43.
[0019]
As shown in FIG. 8, the foamable molding material 45 is injected into the bottom wall molding region c, and from the region c to the solid peripheral wall molding region n, the overhang molding region d, and the hinge half molding region e. The cavity 42 is filled by flowing. Thereby, the box intermediate body 10a is molded.
[0020]
In this case, since the interval f between the bottom wall molding regions c is narrow and the injection pressure of the foamable molding material 45 is high, the molding material 45 does not foam in the bottom wall molding region c. Further, in the solid peripheral wall molding region n, the injection pressure is reduced, but the internal pressure is increased due to the filling of the molding material 45 and the sealing effect. Therefore, the molding material 45 does not foam in the solid peripheral wall molding region n. This foaming suppression phenomenon also occurs in the overhang forming region d and the hinge half forming region e.
[0021]
As shown in FIG. 9, at least one of the male mold 36 and the female mold 37, in the embodiment, the female mold 37 is moved in the mold opening direction a, so that the bottom wall forming region c, the overhang forming region d, and the hinge half The spacings f, g, and h of the molding region e are made to coincide with the thicknesses j, k, and m of the bottom wall 14, the overhang portion 22, and the hinge half body 27, and the seal between the mating surfaces 38 and 39 of both molds 36 and 37. Is released. Thereby, in the bottom wall molding region c, the overhang portion molding region d, and the hinge half body molding region e, the expansion of the volume and the release of the internal pressure are generated, and the molding material 45 in the middle part in the mold opening / closing direction is foamed. Reference numerals 46 and 47 denote foam core layers in the overhang portion 22 and the hinge half body 27. In the solid peripheral wall forming region n, expansion of the volume hardly occurs, so that foaming does not occur.
[0022]
As clearly shown in FIG. 10, the pin hole 30 of the hinge half 27 is formed by a pin-shaped core 48 existing in the male mold 36. Therefore, when the female die 37 moves in the mold opening direction a as described above, the box intermediate body 10 a is fixed to the male die 36 by the pin-shaped core 48 fitted in the pin hole 30. As a result, the opening end face 28 of the luggage box 10 is in close contact with the male mold 36 and foaming of the opening end face 28 is prevented, so that the airtightness between the sheet 11 and the opening end face 28 is improved.
[0023]
Further, as clearly shown in FIG. 11, each reinforcing rib 17 is formed by a groove forming portion 49 existing in the male mold 36, and on the male mold 36 side when the female mold 37 moves in the mold opening direction a as described above. Even if foaming may occur on the outer surface 50 of the hollow projection 16 because it is fixed, foaming that reduces the strength of the base 51 of each reinforcing rib 17 does not occur.
[0024]
Examples of the foamable molding material 45 include a composition containing a thermoplastic resin (thermoplastic synthetic resin) and a foaming agent, and a composition containing a thermoplastic resin, a filler and a foaming agent.
[0025]
Examples of the thermoplastic resin include publicly known ones, such as polystyrene, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, ABS resin, ethylene-vinyl acetate copolymer, polyamide resin, polycarbonate. , Polyethylene terephthalate, polybutylene terephthalate, methacrylic resin and polyvinyl alcohol. Among these, polypropylene is particularly preferable because a relatively lightweight synthetic resin luggage box for motorcycles can be obtained. As a polypropylene, the composition (block copolymer) of a propylene homopolymer, a propylene-alpha-olefin copolymer, a propylene homopolymer, and a propylene-alpha-olefin copolymer can be illustrated. Examples of the α-olefin which is a copolymer component of the copolymer include ethylene, 1 butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dene, 4-methyl-1-pentene, 3 -Methyl-1-pentene etc. are mentioned. The proportion of α-olefin units in the propylene-α-olefin copolymer is preferably 10% or less of all the structural units.
[0026]
Furthermore, as a thermoplastic resin, modified polymers, such as a modified polypropylene by an unsaturated monomer, can also be illustrated.
[0027]
The filler (filler) may be either an organic filler or an inorganic filler, specifically glass fiber, mineral fiber, calcium carbonate, talc, kaolin clay, mica, quartz powder, diatomaceous earth, barium sulfate, Pumice powder, pulp powder, carbon fiber, synthetic fiber, glass hollow body and the like can be exemplified. Of these, glass fiber, talc or mica is preferred. The filler content is preferably 5 to 50% by weight with respect to the entire foamable molding material because a synthetic resin luggage box for motorcycles having excellent rigidity and light weight can be obtained.
[0028]
When blending glass fiber as a filler in polypropylene to make a foamable molding material, because of the excellent compatibility between glass and polypropylene, a rigid synthetic resin luggage box for motorcycles can be obtained. Is preferably modified polypropylene.
[0029]
Examples of the foaming agent include inorganic compounds such as ammonium carbonate and sodium bicarbonate, and organic compounds such as azo compounds, sulfohydrazide compounds, nitroso compounds, and azide compounds. Examples of the azo compound include azodicarbonamide (ADCA), 2,2-azo-1-butyronitrile, azohexahydrobenzonitrile, diazoaminobenzene, and the like, and examples of the sulfohydrazide compound include benzenesulfohydrazide and benzene. -1,3-disulfohydrazide, diphenylsulfone-3,3-disulfohydrazide, diphenyloxide-4,4-disulfohydrazide and the like can be exemplified, and as the nitroso compound, N, N-dinitrosopenta Examples include methylenetetramine (DNPT) and N, N-dimethyl terephthalate. Examples of the azide compound include terephthal azide and P-tert-butylbenzazide. The blending amount of the foaming agent is preferably 0.5 to 5% by weight based on the whole foamable molding material.
[0030]
The foamable molding material can be blended with publicly known additives as necessary. Examples of additives include plasticizers, stabilizers, antioxidants, weathering agents, ultraviolet absorbers, colorants, lubricants, antistatic agents, flame retardants, and elastomers.
[0031]
In addition, the bottom wall 14 may have a solid part in a part thereof.
[0032]
【The invention's effect】
According to the present invention, light in weight, also excellent with a bottom wall having a heat insulating property, it is possible to mass-produce more practical synthetic resin luggage box for a motorcycle having a sufficient strength.
[Brief description of the drawings]
FIG. 1 is a side view of a motorcycle.
FIG. 2 is a cutaway side view of an essential part of a luggage box.
FIG. 3 is a view taken in the direction of arrow 3 in FIG. 2;
4 is a cross-sectional view taken along line 4-4 of FIG.
5 is a cross-sectional view taken along line 5-5 of FIG.
6 is a cross-sectional view taken along line 6-6 of FIG.
FIG. 7 is a schematic cross-sectional view of a mold before filling with a molding material.
FIG. 8 is a schematic cross-sectional view of a mold after filling with a molding material.
FIG. 9 is a schematic cross-sectional view of a mold after foaming of the molding material.
FIG. 10 is a cross-sectional view of the main part showing the relationship between the hinge half and the mold.
FIG. 11 is a cross-sectional view of a main part showing a relationship between a reinforcing rib and a mold.
[Explanation of symbols]
a, b Mold opening / closing direction a Mold opening direction b Mold closing direction c Bottom wall forming region 10 Luggage box 10a Box intermediate body 12 Foam core layer 13 Solid skin layer 14 Solid wall 15 Solid peripheral wall 16 Hollow convex portion 17 Reinforcement rib 27 Hinge half Body 28 Open end face 30 Pin hole 36 Male mold 37 Female mold 38, 39 Mating surface 40 Seal member 41 Mold 42 Cavity 45 Foamable molding material 48 Pin-shaped core

Claims (2)

A bottom wall (14) having a sandwich structure consisting of solid skin layer (13) originating Awakokoroso (12) and covering it, more automated constructed and its bottom wall (14) integral of solid wall (15) In producing a luggage box (10) made of synthetic resin for motorcycles,
A male mold (36) for molding the inner surface side of the luggage box (10) and a female mold (37) for molding the outer surface side of the luggage box (10), and combining both molds (36, 37) A mold (41) capable of sealing between the surfaces (38, 39) is prepared, and by closing the mold (41), a box-forming cavity (between the male mold (36) and the female mold (37) ( 42) and the interval (f) in the mold opening / closing direction (a, b) in the bottom wall forming region (c) of the cavity (42) is smaller than the thickness (j) of the bottom wall (14). Setting and sealing between the mating surfaces (38, 39) of both molds (36, 37);
The foamable molding material (45) is injected into the bottom wall molding region (c), and flows from the region (c) to the solid peripheral wall molding region (n) of the cavity (42), thereby causing the cavity (42). ) Filling in,
At least one of the male mold (36) and the female mold (37) is moved in the mold opening direction (a), and the interval (f) of the bottom wall forming region (c) is set to the bottom wall (14). By matching the thickness (j) and releasing the seal between the mating surfaces (38, 39) of both molds (36, 37), the mold opening / closing direction (a, b) of the bottom wall forming region (c) And a step of foaming the foamable molding material (45) in an intermediate portion. A method for producing a synthetic resin luggage box for motorcycles. The luggage box (10) includes a hinge half (27) provided with a pin hole (30) extending in a direction intersecting the mold opening / closing direction (a, b) so as to be connected to the opening end face (28). A pin-shaped core (15) fitted into the pin hole (30) when moving in the mold opening direction (a) of at least one of the male mold (36) and the female mold (37) 48) by fixing the box intermediate (10a) on the male (36) according to claim 1 method for manufacturing motorcycle plastic luggage box according.

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