JP5090970B2 - Mold - Google Patents

Description

  The present invention relates to a molding die for molding a cup-shaped molded body having a hole in the bottom, such as a seedling pot, a flower pot, a flower pot cover, etc., from a cylindrical synthetic resin sheet.

  For example, a seedling pot formed of a synthetic resin sheet made of polypropylene or the like is generally used for growing and selling plant seedlings, but these seedling pots are inferior in decorativeness, and are insulated. Because of its low nature, when used in cold regions or regions with a significant temperature difference, it has a serious adverse effect on the growth of plants and seedlings. Therefore, the applicant of the present application can use the exterior body described in Patent Document 1 formed from a synthetic resin sheet having heat-shrinkability (hereinafter also referred to as a heat-shrinkable sheet) as a flower pot. It was found that it can be used as a seedling pot with excellent decorativeness.

  This seedling pot is formed in a cylindrical shape with a heat-shrinkable sheet laminated with a decorative film decorated by gravure printing or the like, and heat-shrinks in the circumferential direction in a state where the cylindrical body is fitted in a mold. After forming the body part in close contact with the peripheral surface of the molding die, the bottom part is molded by pressing the upper end portion of the cylindrical body that wraps around the upper part of the molding die against the upper surface of the molding die. When the upper end edge of the cylindrical body is thermally contracted, the upper end opening becomes smaller and finally becomes a drain hole formed in the bottom.

JP 2006-248539 A

  By the way, as described above, when a heat-shrinkable cylindrical body is fitted on a mold and is heat-shrinked, the upper end portion of the cylindrical body serving as the bottom portion protrudes above the mold, Since it is not supported at all in the process, the heat shrink does not occur uniformly, and the upper edge of the cylindrical body may curl inward.

  Therefore, after the cylindrical body is heat-shrinked, even if the bottom part is molded by pressing the upper end of the cylindrical body that has wrapped around the molding die against the upper surface of the molding die by the pressing member, the water formed on the bottom part There is a problem that the diameter and shape of the hole are different, and the water hole having a predetermined shape and diameter cannot be reliably formed in a stable state.

  Then, the subject of this invention is providing the shaping | molding die which can form reliably the hole of a predetermined | prescribed shape and a diameter in the bottom in the bottom of the cup-shaped molded object shape | molded from a cylindrical body. .

  In order to solve the above-mentioned problems, the invention according to claim 1 is to form a cup-shaped molded body having a hole formed in the bottom from a cylindrical molded material formed of a heat-shrinkable synthetic resin sheet. A main body formed in a predetermined shape so that the upper side corresponds to the bottom side of the molded body and the lower side corresponds to the upper end opening side of the molded body, and the main body is covered with the mold. When the fitted cylindrical material to be heated is shrunk, a pre-shaped part that preliminarily shapes the upper end of the material to be molded, and the molded body after molding is pushed up and released from the main body part. A mold part, and the preliminary shaping part is a movable shaping member supported so as to be movable in and out with respect to a bottom molding surface for molding the bottom part of the molded body, and the movable shaping member is connected to the bottom molding surface. Biasing means for biasing to a state of protruding from the By heating and shrinking the cylindrical molding material fitted to the part, the upper end portion of the molding material is aligned with the movable shaping member protruding from the bottom molding surface, and the pressing member causes the A molding die characterized in that the bottom of the molded body is molded by pressing down the movable shaping member and pressing the upper end of the material to be molded against the bottom molding surface.

  As described above, the mold according to the first aspect of the present invention projects the upper end portion of the molding material which becomes the bottom of the molded body from the bottom molding surface when the fitted cylindrical molding material is heated and shrunk. Since it was preliminarily shaped by moving along the movable shaping member, when the bottom of the molded body is molded by pressing down the movable shaping member with the pressing member and pressing the upper end of the molding material against the bottom molding surface, the molded body A hole having a predetermined shape and a diameter can be reliably formed in a stable state at the bottom.

  Hereinafter, embodiments will be described with reference to the drawings. 1 (a), 1 (b), and 2 are formed from a tubular body M formed of a heat-shrinkable sheet as shown in FIG. 8, and a drain hole h is formed at the bottom as shown in FIG. The shaping | molding die 1 for shape | molding the made cup-shaped seedling pot P is shown. In FIG. 9, the seedling pot P is shown upside down, that is, in a state where the bottom part is on the top.

  As the heat-shrinkable sheet forming the cylindrical body M, a sheet having a heat-shrinkable property capable of mainly thermally shrinking in at least one direction (the circumferential direction of the cylindrical body M) is used. For example, when the heat-shrinkable sheet is composed of a single-layer sheet, a sheet having heat insulation and mainly heat-shrinking in one direction is used. When the heat-shrinkable sheet is composed of a laminated sheet having a multilayer structure including a heat insulating layer, at least one of the layers has heat-shrinkability, and the layer having the heat-shrinkability is non-heat-shrinkable. By pulling and contracting the other layer, it is sufficient that the entire laminated sheet can shrink in at least one direction, and it is particularly desirable to use a laminated sheet including a heat insulating layer and a synthetic resin sheet.

  The heat insulation layer can be formed of, for example, an opaque foamed resin sheet having a thickness of about 0.1 to 1 mm, a nonwoven fabric, or the like, and may have heat shrinkability. Moreover, as will be described later, when the laminated synthetic resin sheet has heat shrinkability, the heat insulating layer itself does not need to have heat shrinkability. The foamed resin sheet can be formed of polystyrene, polyethylene, polypropylene, polyurethane, or the like, and particularly preferably formed of a styrene resin having high foamability. Moreover, as a foaming method, well-known foaming methods, such as physical foaming and chemical foaming, can be employ | adopted, and a foaming ratio of about 2-10 is desirable from a heat insulating viewpoint. To these resins, additives such as various fillers, colorants, plasticizers, stabilizers and the like may be appropriately added as necessary. In addition, as the non-woven fabric, it is possible to use a sheet made of fibers such as polyolefins such as polyester and polyethylene, polyolefin elastomers, rayon, nylon and cupra. Solid fibers, hollow fibers, or mixed fibers thereof can be used as the fibers forming the nonwoven fabric, and it is particularly desirable to use hollow fibers or mixed fibers excellent in heat insulation.

  The synthetic resin sheet is not particularly limited, and for example, one kind or two kinds selected from thermoplastic resins such as styrene resins such as polystyrene, polyester resins such as polyethylene terephthalate, and olefin resins such as polypropylene and cyclic olefins. A sheet formed of a resin composition containing the above mixture (also generally referred to as a film) and a laminated sheet obtained by laminating two or more of these sheets can be used, and has a thickness of about 20 to 70 μm. Things are desirable. The synthetic resin sheet may or may not have heat shrinkability, but it is desirable to use a sheet having excellent transparency.

  If necessary, the heat-shrinkable sheet is provided with a design indication such as a single-color or multi-colored pattern or various decorative patterns by gravure printing, and the heat-shrinkable sheet is a heat insulating layer and a synthetic resin sheet. In the case of being formed by a laminated sheet containing, it is desirable to give a design indication to the inner surface of the synthetic resin sheet, but the design indication may be given to the outer surface of the synthetic tree sheet or the heat insulating layer.

  As the heat-shrinkable sheet, a synthetic resin sheet not having heat-shrinkability (for example, an unstretched polystyrene film) and a foamed resin sheet having heat-shrinkability (for example, a stretched polystyrene foamed resin sheet) are laminated. It is desirable to use a laminated sheet. In the case of using a laminated sheet, it is desirable that the upper layer and the lower layer are the same material or the same kind of material (for example, the above-described styrene-based material). This is because, when the heat-shrinkable sheet is formed into a cylindrical shape, the side end portions can be reliably bonded with an adhesive. In addition, when a laminated sheet of a synthetic resin sheet and a foamed resin sheet is used as the heat-shrinkable sheet, the heat-shrinkable sheet is formed in a cylindrical shape so that the synthetic resin sheet forms the outer surface of the seedling pot P It is desirable to do.

  Adhesion between the synthetic resin sheet and the heat insulating layer is usually an adhesive employed in a dry laminating method or a wet laminating method, for example, an acrylic, polyurethane, vinyl acetate, vinyl chloride, rubber or other solvent. A mold adhesive or a water-soluble adhesive can be used. In addition, the heat-adhesive sheet | seat which has a heat insulation layer is not restricted to the laminated sheet which has a synthetic resin sheet and a heat insulation layer, For example, you may be formed only from the heat insulation layer which has heat shrinkability. In addition, the heat-adhesive sheet may be a synthetic resin sheet or a heat-insulating layer, or a laminated body having a multilayer structure, and a laminated sheet having three or more layers as a whole can be used.

  The heat shrinkage rate of the heat-shrinkable sheet is, for example, a heat shrinkage rate in one direction (main heat shrinkage direction) (immersion in a glycerin bath corresponding to 160 ° C. for 5 seconds) is 50% or more, preferably 60% or more More preferably, it is 70% or more. Moreover, the heat-shrinkable sheet may be slightly heat-shrinked in the other direction (direction orthogonal to the one direction), and the heat-shrinkage rate in the other direction (immersed in a glycerin bath corresponding to 160 ° C. for 5 seconds) The thing of about 0.5 to 10% is illustrated. However, heat shrinkage rate (%) = [{(original length in one direction (or other direction)) − (length after immersion in one direction (or other direction))} / (one direction (or other direction) ) Original length)] × 100.

  As shown in FIGS. 1 (a), 1 (b) and 2, the molding die 1 is predetermined so that the upper side corresponds to the bottom side of the seedling pot P and the lower side corresponds to the upper end opening side of the seedling pot P. A main body portion 10 formed in a shape, a holding portion 20 that holds the lower end portion of the tubular body M fitted to the main body portion 10 between the main body portion 10 and a seedling pot P after completion of molding. A release part 30 that is pushed up and released from the main body part 10 and a pre-shaping part 40 that preliminarily shapes the upper end of the cylindrical body M when the cylindrical body M fitted to the main body part 10 is heated and shrunk. The preliminary shaping portion 40 is attached to the release portion 30.

  As shown in FIG. 2 and FIGS. 3A and 3B, the main body 10 includes a cylindrical die 11 whose outer shape is a substantially frustoconical outer shape that forms the body forming surface of the seedling pot P. The inner peripheral portion of the cylindrical mold 11 is formed such that the inner diameter of the upper half portion is smaller than the inner diameter of the lower half portion, and the inner flange portion projecting radially inward is formed at the lower portion of the upper half portion. 12 is formed.

  The inner flange portion 12 is provided with a positioning pin 13 for positioning the release portion 40 and a recess 14 into which a stopper 43 of a pre-shaping portion 40 described later is fitted. A plurality of through holes 15 extending from the lower end surface flush with the lower surface of the inner flange portion 12 to the upper end surface are formed in the upper half of the cylindrical mold 11 having a small diameter.

  The holding portion 20 includes a planar circular base 21 on which the main body portion 10 is fixedly installed, four holding claws 22 supported on the base 21 so as to be slidable in the radial direction, and the holding claws 22. It comprises an annular coil spring 23 fitted in a recess formed on the outer end surface, and the holding claw 22 is urged radially inward by the coil spring 23, and the holding claw 22 is the lower outer periphery of the main body 10. The lower end portion of the cylindrical body M is sandwiched between the surface and the surface.

  As shown in FIGS. 2 and 4A to 4C, the release part 30 includes a circular cup-shaped member 31 accommodated in an internal space above the inner flange part 11 in the cylindrical mold 11. And a flange portion 34 that protrudes outward from the upper end portion of the cup-shaped member 31 and is placed on the upper end surface of the cylindrical mold 11. A positioning pin of the main body portion 10 is provided at the bottom of the cup-shaped member 31. A positioning hole 32 into which 13 is fitted, and three pin insertion holes 33 into which slide pins 42 of a pre-shaping part 40 described later are inserted, and a rod R for raising and lowering the release part 30 is fixed. ing.

  As shown in FIGS. 2 and 5A to 5C, the preliminary shaping portion 40 includes an annular movable shaping member 41 that can be fitted into the cup-shaped member 31 of the release portion 30, and the movable shaping member. Three slide pins 42 inserted into the pin insertion hole 33 of the cup-shaped member 31 of the release part 30, which are continuously provided on the lower surface of the member 41, and a coil spring 44 that urges the movable shaping member 41 upward. A stopper 43 having a function of preventing the slide pin 42 from being detached is fixed to the lower end portion of the slide pin 42.

  The molding operation of the seedling pot P using the molding die 1 configured as described above will be described below with reference to FIGS. 6 and 7. First, as shown in FIG. 6A, when the cylindrical body M is fitted onto the mold 1 and pushed down, the holding claws 22 of the holding portion 20 are spread outward in the radial direction, and the lower end of the cylindrical body M is expanded. The portion is held by being sandwiched between the lower outer peripheral surface of the main body portion 10 and the holding claw 22.

  In this state, when the cylindrical body M fitted to the mold 1 is heated and shrunk, the cylindrical body M becomes the outer peripheral surface of the cylindrical mold 11 of the main body 10 and the mold release as shown in FIG. The body part is molded by being in close contact with the outer peripheral surface of the flange part 34 of the part 30, while the upper part of the cylindrical body M is thermally contracted so as to be along the upper end surface of the flange part 34 of the release part 30, The bottom part is preformed by heat shrinking so that the upper edge of the body M is along the upper surface of the movable shaping member 41 of the preliminary shaping part 40. At this time, the upper end opening of the cylindrical body M is thermally contracted without curling the upper end edge to the inner surface side, and the drain hole h of the seedling pot P is always in a stable state on the preformed bottom. Holes having substantially the same diameter are formed.

  Subsequently, as shown in FIG. 7 (a), the top surface of the flange portion 34 of the mold release portion 30 and the preliminary shaping are formed so that the bottom portion preliminarily shaped by pressing down the movable shaping member 41 by the pressing member PM from above. By pressing on the upper surface of the movable shaping member 41 of the part 40, the bottom part which has the drain hole h of a predetermined diameter is shape | molded, and the seedling pot P is completed.

  Finally, as shown in FIG. 4B, when the release part 30 is lifted, the seedling pot P after completion of the molding is detached from the cylindrical mold 11 of the main body part 10 and can be transferred. At this time, the movable shaping member 41 of the preliminary shaping portion 40 protrudes upward from the upper surface of the flange portion 34 of the mold release portion 30 by the urging force of the coil spring 44, and the movable shaping member 41 transfers the molded seedling pot P to the movable shaping member 41. It is in a state of being lifted from the release part 30.

  As described above, the mold 1 is configured such that when the fitted tubular body M is heated and contracted, the upper end portion of the tubular body M, which is the bottom of the seedling pot P, is the flange of the release part 30 which is the bottom molding surface. After preliminarily shaping by moving along the movable shaping member 41 protruding from the upper surface of the portion 34, the bottom of the mold release portion 30 which becomes the bottom molding surface is formed by pressing the movable shaping member 41 down and preliminarily shaping the bottom portion. Since the bottom part of the seedling pot P is molded by pressing against the upper surface and the upper surface of the movable shaping member 41 of the preliminary shaping part 40, the upper end part of the cylindrical body that becomes the bottom part in the process of heat shrinkage is not supported at all. Compared with this mold, the upper part of the tubular body M is uniformly heat-shrinked, and the upper edge of the tubular body M is not curled inward, and water having a predetermined shape and caliber is formed at the bottom of the seedling pot P. Securely with the hole h in a stable state It can be formed.

  In the above-described embodiment, an annular member having a certain thickness and a substantially flat top surface is employed as the movable shaping member 41 of the preliminary shaping unit 40, but is not limited thereto. As long as the cylindrical body M fitted on the base is heated and contracted, the cylindrical body M has a shape in which the upper edge of the cylindrical body M is uniformly aligned, for example, a conical shape, a truncated cone shape, a columnar shape, a cylindrical shape, a disc shape, etc. Various shapes can be employed.

  Moreover, in embodiment mentioned above, although the coil spring 44 is employ | adopted as a biasing means which biases the movable shaping member 41 of the preliminary shaping part 40 upward, it is not limited to this, For example, It is also possible to employ a compressible elastic member such as rubber or sponge having heat resistance, and various expansion / contraction mechanisms using fluid such as air.

  In the above-described embodiment, the mold for molding the seedling pot P having the drain hole h at the bottom has been described. However, the present invention is not limited to this, and the mold of the present invention has a predetermined shape at the bottom. Needless to say, the present invention can be applied to molding a flower pot, a flower pot cover or the like in which a hole having a shape and a diameter is formed.

  It can be applied when molding a cup-shaped molded body having a hole in the bottom.

(A) is a top view which shows one Embodiment of the shaping | molding die concerning this invention, (b) is a side view which shows the shaping | molding die same as the above. It is sectional drawing along the XX line of Fig.1 (a). (A) is a top view which shows the main-body part of a shaping | molding die same as the above, (b) is a side view which shows a main-body part same as the above. (A) is a top view which shows the mold release part of a shaping | molding die same as the above, (b) is a side view which shows a mold release part same as the above, (c) is a bottom view which shows a mold release part same as the above. (A) is a top view which shows the preliminary shaping part of a shaping | molding die same as the above, (b) is a side view which shows the preliminary shaping part same as the above, (c) is a bottom view which shows the preliminary shaping part same as the above. (A), (b) is process drawing which shows the shaping | molding operation | work of the seedling pot using the shaping | molding die same as the above. (A), (b) is process drawing which shows the shaping | molding operation | work of the seedling pot using the shaping | molding die same as the above. It is a perspective view which shows the cylindrical body for raising seedling pots same as the above. It is a perspective view which shows the seedling raising pot same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 10 Main body part 11 Cylindrical type | mold 12 Inner flange part 13 Positioning pin 14 Recessed part 15 Through hole 20 Holding part 21 Base 22 Holding claw 23 Coil spring 30 Mold release part 31 Cup-shaped member 32 Positioning hole 33 Pin insertion hole 34 Flange part 40 Preliminary shaping part 41 Movable shaping member 42 Slide pin 43 Stopper 44 Coil spring M Cylindrical body P Nursery pot PM Pressing member

Claims (1)

A molding die for molding a cup-shaped molded body in which a hole is formed in the bottom from a cylindrical molding material formed by a synthetic resin sheet having heat shrinkability,
A main body formed in a predetermined shape such that the upper side corresponds to the bottom side of the molded body and the lower side corresponds to the upper end opening side of the molded body;
A pre-shaping part for preliminarily shaping the upper end of the molding material when the cylindrical molding material fitted to the main body is heated and shrunk;
A mold release part that pushes up the molded body after completion of molding and releases it from the main body part,
The preliminary shaping unit is
A movable shaping member supported so as to be movable in and out with respect to a bottom molding surface for molding the bottom of the molded body, and a biasing means for biasing the movable shaping member to a state of protruding from the bottom molding surface; Have
By pressing and shrinking the cylindrical molding material fitted to the main body, the pressing member in a state where the upper end portion of the molding material is aligned with the movable shaping member protruding from the bottom molding surface. A molding die characterized in that the bottom of the molded body is molded by pressing down the movable shaping member and pressing the upper end of the molded body against the bottom molding surface.

Images