Injection molding apparatus

Abstract

To provide a new injection molding apparatus capable of easily and quickly positioning an opening end part of a pouch at a required portion of an inner mold member of inner mold means in a molding die, thus enabling easy and quick insertion of the opening end part of the pouch into the molding die, and thus significantly improving a manufacturing efficiency of a composite container, this can significantly improve the manufacturing efficiency of the composite container.SOLUTION: A specific form of an insert jig 30 that is detachably connected to an inner mold member 8 of inner mold means in a molding die is prepared, an opening end of a pouch 102 is fitted into the insert jig 30 from a rear end, and the opening end of the pouch 102 is caused to protrude beyond a tip face 32 of the insert jig 30. The insert jig 30 is then connected to the inner mold member 8 together with the pouch 102 by contacting the tip face 32 with a base face 12 of the inner mold member 8.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an injection molding apparatus for injection molding a synthetic resin neck member by inserting an open end portion of a synthetic resin film pouch, and more specifically, for injection molding a neck member having an annular bottom wall that abuts or is close to the open end of the pouch and a hanging wall that hangs down from this bottom wall and is joined to the inner peripheral surface or outer peripheral surface of the open end portion of the pouch, to manufacture a composite container composed of the pouch and the neck member.

Background Art

[0002] Patent Document 1 below discloses a composite container (bag cup) composed of a synthetic resin film pouch having a circular open end and a neck member (mouth ring) heat-sealed to the inner peripheral surface of the open end portion of the pouch. The neck member includes an annular bottom wall (flange portion) and a cylindrical hanging wall (body portion) that hangs downward from this bottom wall, and the outer peripheral surface of the hanging wall is heat-sealed to the inner peripheral surface of the open end portion of the pouch.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The composite container disclosed in Patent Document 1, as described above, is formed by positioning the hanging wall of the neck member within the opening end of the pouch as required and heat-welding the opening end of the pouch to the hanging wall. This process is relatively complicated, and the joint strength between the opening end of the pouch and the hanging wall of the neck member is not always sufficient. To solve this problem, the present inventors attempted to manufacture a composite container composed of a pouch and a neck member by inserting the opening end of the pouch and injection molding the neck member. However, in such manufacturing, it is necessary to insert the pouch into the mold of the injection molding machine as required, and more specifically, to position the opening end of the pouch at the required location on the inner mold member of the inner mold means in the mold. However, because the inner mold member is located relatively deep inside the injection molding machine body and there is only a relatively small space around it, the manual operation of inserting the pouch into the mold as required is relatively difficult and complicated, and the manufacturing efficiency of composite containers is extremely low.

[0005] The present invention has been made in view of the above facts, and its main technical problem is to provide a novel and improved injection molding apparatus that can easily and quickly position the opening end of a pouch at a required location on the inner mold member of the inner mold means in the molding die, and therefore can easily and quickly insert the opening end of a pouch into the molding die, thereby dramatically improving the manufacturing efficiency of composite containers. [Means for solving the problem]

[0006] As a result of diligent research and experimentation, the inventors have found that the main technical problem described above can be solved by providing a specific type of insert jig that is detachably connected to the inner mold member of the inner mold means in the molding die, fitting the opening end of the pouch onto the insert jig from its rear end, allowing the opening end of the pouch to protrude beyond the front surface of the insert jig, and then connecting the insert jig together with the pouch by bringing its front surface into contact with the base end surface of the inner mold member, thereby enabling the pouch to be inserted into the molding die.

[0007] In other words, according to the present invention, as an injection molding apparatus that achieves the above-mentioned main technical problem, An injection molding apparatus for manufacturing a composite container composed of a pouch and a neck member, by inserting the open end of a synthetic resin film pouch and injection molding a synthetic resin neck member having a ring-shaped bottom wall that abuts against or is close to the open end of the pouch and a tubular hanging wall that hangs down from the bottom wall and is joined to the inner or outer circumferential surface of the open end of the pouch, The molding die comprises an inner molding means and an outer molding means, The inner molding means includes an inner mold member that defines at least the inner or outer surface of the hanging wall and the inner or outer surface of the bottom wall of the neck member, Furthermore, the inner mold member is equipped with an insert jig that is detachably connected to the base end face, The insert jig has a tip surface and an outer peripheral surface hanging down from the outer peripheral edge of the tip surface, the tip surface of the insert jig corresponds to the base end surface of the inner mold member, and the tip portion of the outer peripheral surface of the insert jig corresponds to the inner peripheral surface of the opening end of the pouch. The opening end of the pouch is fitted into the insert jig from its rear end, so that the opening end of the pouch protrudes beyond the front surface of the insert jig, and then the insert jig together with the pouch is connected to the inner mold member by bringing the front surface of the insert jig into contact with the base end surface of the inner mold member, thereby inserting the pouch into the mold. An injection molding apparatus characterized by the above is provided.

[0008] Preferably, the insert fixture comprises at least two fixtures, one of which is connected to the inner mold member, allowing the opening end of the pouch to be fitted into the other fixture while the neck member is being injection molded.

[0009] Furthermore, the support includes an upper end surface against which the tip surface of the insert jig abuts, an outer peripheral surface hanging down from the outer peripheral edge of the upper end surface, and a flange surface protruding from the lower end of the outer peripheral surface. When the tip surface of the insert jig is brought into contact with the upper end surface of the support and the insert jig is mounted on the support, the tip portion of the outer peripheral surface of the insert jig and the outer peripheral surface of the support define a continuous cylindrical outer peripheral surface, and this continuous outer peripheral surface corresponds to the inner peripheral surface of the opening end of the pouch. With the insert jig mounted on the support, the open end of the pouch is fitted onto the insert jig and the support from the rear end side of the insert jig, so that the open end of the pouch contacts the flange surface of the support, then the insert jig and the pouch are detached from the support as a single unit, and thereafter the insert jig together with the pouch is connected to the inner mold member by bringing the front surface of the insert jig into contact with the base end surface of the inner mold member, thereby preferably inserting the pouch into the molding die.

[0010] Preferably, at least one restrained projection is provided on the tip surface of the insert jig, and at least one restraining mechanism is provided on the base end surface of the inner mold member to receive and release the restrained projection, so that the insert jig is detachably connected to the inner mold member by the release of the restrained projection by the restraining mechanism. The pouch has at least one side seal portion extending from the open end, and the support member is provided with at least one side seal portion receiving gap located radially outward from the outer circumferential surface and extending axially, so that when the open end of the pouch is fitted into the insert jig and the support member with the insert jig mounted on the support member, it is preferable that the side seal portion of the pouch is received within the side seal portion receiving gap. The upper end face of the support is ring-shaped, a groove extending in the diametrically is provided on the radially inward side of the outer circumferential surface of the support, and at least one restraining projection is provided on the tip face of the insert jig. When the insert jig is mounted on the support, it is desirable that the restraining projection enters the groove, thereby restricting the angular position of the insert jig relative to the support. Preferably, the opening end of the pouch is cylindrical, at least the tip of the outer circumferential surface of the insert jig is defined by a cylindrical circumferential wall, the circumferential wall of the insert jig has at least two circumferentially extending arc-shaped openings formed at equal intervals in the circumferential direction, and each of the arc-shaped openings is provided with an adjustment member having an outer circumferential surface that is arc-shaped, corresponding to the outer circumferential surface of the circumferential wall, which is movable between a protruding position where its outer circumferential surface protrudes radially outward from the outer circumferential surface of the circumferential wall and a retracted position where its outer circumferential surface retracts radially inward from the outer circumferential surface of the circumferential wall, and each of the adjustment members is provided with an elastic member that elastically biases to the protruding position. Preferably, the outer circumferential edge of the tip of the insert jig is circular, the tip of the outer circumferential surface of the insert jig is cylindrical, and the rear end of the insert jig is conical or frustoconical in shape, with the outer diameter gradually increasing towards the tip. [Effects of the Invention]

[0011] In the injection molding apparatus of the present invention, the opening end portion of the pouch is fitted onto an insert jig that has detached from the inner mold member of the inner mold means in the mold disposed in the main body of the injection molding apparatus. Accordingly, the opening end portion of the pouch can be easily and quickly fitted onto the insert jig as required. Next, by connecting the insert jig together with the pouch to the inner mold member, the opening end portion of the pouch can be positioned at a required portion of the inner mold member. Accordingly, the opening end portion of the pouch can be easily and quickly inserted into the mold, and thus the manufacturing efficiency of the composite container can be significantly improved.

Brief Description of the Drawings

[0012] [Figure 1] Front view showing an example of a composite container including a mouth and neck member injection molded by an injection molding apparatus configured according to the present invention. [Figure 2] Plan view of the composite container shown in FIG. 1. [Figure 3] Cross-sectional view taken along line III-III of FIG. 2. [Figure 4] Cross-sectional view taken along line IV-IV of FIG. 2. [Figure 5] Front view showing the pouch of the composite container shown in FIG. 1. [Figure 6] Plan view of the pouch shown in FIG. 5. [Figure 7] Cross-sectional view showing a preferred embodiment of an injection molding apparatus configured according to the present invention together with a pouch inserted into the mold. [Figure 8] Front view showing the inner mold member in the injection molding apparatus shown in FIG. 7. [Figure 9] Plan view of the inner mold member shown in FIG. 8. [Figure 10] Cross-sectional view taken along line X-X of FIG. 9. [Figure 11] Bottom view of the inner mold member shown in FIG. 8. [Figure 12] Perspective view of a pair of outer mold means in the injection molding apparatus shown in FIG. 7. [Figure 13] Front view showing the insert jig in the injection molding apparatus shown in FIG. 7. [Figure 14]Side view of the insert jig shown in FIG. 13. [Figure 15] Plan view of the insert jig shown in FIG. 13. [Figure 16] Cross-sectional view taken along line A-A of FIG. 13. [Figure 17] Front view of the state where the open end of the pouch is fitted to the inner mold member when the pair of outer mold members are in the open position in the injection molding apparatus shown in FIG. 7. [Figure 18] Perspective view of the state where the insert jig shown in FIG. 13 is attached to the support provided in the injection molding apparatus. [Figure 19] Front view of the state shown in FIG. 18. [Figure 20] Side view of the state shown in FIG. 18. [Figure 21] Plan view of the state shown in FIG. 18. [Figure 22] Plan view of the support shown in FIG. 18. [Figure 23] Cross-sectional view taken along line A-A of FIG. 21 in the state where the open end of the pouch is fitted to the insert jig and the support shown in FIG. 18. [Figure 24] Cross-sectional view taken along line B-B of FIG. 21 in the state where the open end of the pouch is fitted to the insert jig and the support shown in FIG. 18.

Embodiments for Carrying Out the Invention

[0013] Hereinafter, a preferred embodiment of an injection molding apparatus configured according to the present invention will be described in more detail with reference to the accompanying drawings.

[0014] For the sake of convenience, prior to the injection molding apparatus configured according to the present invention, a composite container provided with a neck member injection-molded thereby will be described. An example of such a composite container is shown in FIGS. 1 to 4.

[0015] As shown in FIGS. 1 to 4, the composite container 100 is composed of a pouch 102 made of a synthetic resin film and a neck member 104 made of a synthetic resin obtained by inserting the pouch 102 and injection molding, which will be described in detail later.

[0016] Referring to Figures 5 and 6, the pouch 102 has an opening end 106 at its upper end, which is preferably circular. The pouch 102 can be formed from a single synthetic resin film (in which case there is one side seal), but in the illustrated embodiment it is formed from two synthetic resin films, and two side seals 108a and 108b are arranged at a 180-degree interval in the circumferential direction. Furthermore, in the illustrated embodiment, bifurcated seals 110a-1 and 110a-2 and 110b-1 and 110b-2 are provided, extending downward from the lower ends of each of the two side seal portions 108a and 108b toward both sides in the circumferential direction and radially inward, respectively. In addition, a bottom seal 112-1 is provided connecting one lower end of the bifurcated seals 110a-1 and 110a-2 to one lower end of the bifurcated seals 110b-1 and 110b-2, and a bottom seal 112-2 is provided connecting the other lower end of the bifurcated seals 110a-1 and 110a-2 to the other lower end of the bifurcated seals 110b-1 and 110b-2. Thus, a cup-shaped pouch 102 is formed, closed except for the open end 106. The synthetic resin film forming the pouch 102 may preferably be a single-layer film or a laminated film made by laminating multiple layers. A preferred example is a three-layer synthetic resin film having an inner layer made of low-density polyethylene with excellent adhesion to the neck member 104, which is conveniently made of high-density polyethylene as will be mentioned later; an intermediate layer made of nylon with excellent gas barrier properties; and an outer layer made of polyethylene terephthalate with excellent mechanical properties. The illustrated pouch 102 can be formed by heat welding two synthetic resin films at the side seal portions 108a and 108b, the bifurcated seals 110a-1 and 110a-2 and 110b-1 and 110b-2, and the bottom seals 112-1 and 112-2. The pouch 102 itself may be in a form well known to those skilled in the art, and therefore a detailed description of the pouch 102 itself will be omitted in this specification.

[0017] Continuing the explanation with reference to Figures 1 to 4, the neck member 104 in the illustrated embodiment comprises an annular bottom wall 114 and a cylindrical hanging wall 116 that hangs downward from the inner periphery of the bottom wall 114, with the hanging wall 116 being thinner than the bottom wall 114. It is convenient that the lower surface of the bottom wall 114 abuts against or is close to the upper end, i.e., the opening end 106, of the pouch 102. The lower end of the inner circumferential surface of the hanging wall 116 is inclined radially outward toward downward, and the thickness of the lower end of the hanging wall 116 gradually decreases toward downward. As will be described in more detail later, the neck member 104 is formed by inserting the opening end of the pouch 102 and injection molding, and the outer circumferential surface of the hanging wall 116 of the neck member 104 is joined to the inner circumferential surface of the opening end of the pouch 102. The illustrated neck member 104 further includes a cylindrical mounting wall 118 extending upward from the upper surface of the bottom wall 114. An annular groove 120 is provided near the upper end of the outer circumferential surface of the mounting wall 118, and an annular groove 122 is provided near the lower end. Male threads 124 are also provided on the main outer circumferential surface of the mounting wall 118. The inner circumferential surface of the mounting wall 118 is continuous with the inner circumferential surface of the hanging wall 116 in the vertical direction. Such a neck member 104 can be molded from a suitable synthetic resin such as polyethylene, polypropylene, nylon, and polyethylene terephthalate. If the pouch 102 is formed from a three-layer synthetic resin film having an inner layer made of low-density polyethylene, an intermediate layer made of nylon, and an outer layer made of polyethylene terephthalate as described above, it is advantageous for the neck member 104 to be made of high-density polyethylene in terms of adhesion to the polyethylene inner layer, etc.

[0018] In the composite container 100 as described above, the required contents are contained within the composite container 100, and a lid (not shown) is attached to the neck member 104 to close the opening defined on the top surface of the neck member 104. The lid, which can be formed from a suitable synthetic resin such as polyethylene, polypropylene, nylon, and polyethylene terephthalate, similar to the neck member 104, may be of a well-known form, for example, having a circular top wall and a cylindrical skirt wall hanging down from the periphery of this top wall, with a female thread formed on the inner surface of the skirt wall, and is attached to the neck member 104 by fitting it onto the neck member 104 and screwing the female thread formed on the skirt wall into the male thread formed on the mounting wall 118 of the neck member 104.

[0019] Next, with reference to Figures 7 to 24, a preferred embodiment of an injection molding apparatus configured according to the present invention for inserting the opening end of the pouch 102 and injection molding the neck member 104 will be described. As shown in Figure 7, the injection molding apparatus, shown as a whole by number 2, comprises a mold composed of an inner mold means and an outer mold means. Referring to Figures 8 to 11 in conjunction with Figure 7, the inner mold means includes an inner mold member 8 that defines at least the inner circumferential surface of the hanging wall 116 of the neck member 104. As clearly shown in Figures 8 and 10, the inner mold member 8 has a cylindrical main part 8a and a short cylindrical protruding part 8b. The lower end of the main part 8a has an outer diameter that gradually increases downward and is smoothly connected to the upper end of the outer circumferential surface of the protruding part 8b. A flange 10 that extends substantially horizontally outward is connected to the upper end of the outer circumferential surface of the main part 8a. The lower surface of the inner mold member 8, which is also called the base end surface and is indicated by the number 12, has an annular projection 14 that protrudes downward along its outer edge. The longitudinal cross-sectional shape of the annular projection 14 is a trapezoid that gradually narrows towards the bottom. The outer circumferential surface of the main part 8a of the inner mold member 8 defines the inner circumferential surface of the bottom wall 114 of the neck member 104, the inner circumferential surface of the hanging wall 116, and the inner circumferential surface of the mounting wall 118, while the lower surface of the flange 10 of the inner mold member 8 defines the upper end surface of the mounting wall 118.

[0020] Continuing the explanation with reference to Figures 9 and 10 along with Figure 7, resin channels 18a and 18b are formed in the inner mold member 8 at multiple positions spaced apart in the circumferential direction, in the illustrated case at two positions spaced 180 degrees apart. Each of the resin channels 18a and 18b has a main portion 18a-1 and 18b-1 that extends vertically downward from the upper end surface of the inner mold member 8, and a downstream portion 18a-2 and 18b-2 that extends radially outward downward from the lower ends of the main portions 18a-1 and 18b-1 and opens to the lower end of the main portion 8a of the inner mold member 8, i.e., the surface that defines the lower half of the inner circumferential surface of the hanging wall 116 of the neck member 104.

[0021] In the illustrated embodiment, a restraining mechanism is provided on the base end surface 12 of the inner mold member 8 that receives a restrained projection formed on the tip surface of an insert jig, which will be described later, and restrains it in a way that allows it to be released. As such a restraining mechanism, the product name "One-Way Clamper" manufactured and sold by IMAO Corporation can be used. In the illustrated embodiment, two holes 20a and 20b that penetrate vertically are formed at a distance from each other in the central part of the base end surface 12 of the inner mold member 8, and restraining mechanisms 21a and 21b are embedded in these two holes 20a and 20b, respectively.

[0022] Referring to Figure 12 along with Figure 7, the outer molding means includes a pair of outer mold members 22a and 22b. The pair of outer mold members 22a and 22b are symmetrical in shape with respect to each other and are movable between a closed position in which their circumferential end faces, described later, abut each other, and an open position which is radially outwardly displaced from the closed position. As can be clearly understood by referring to Figure 12, each of the pair of outer mold members 22a and 22b has a substantially semicircular inner circumferential surface 24a and 24b and circumferential end faces 26a-1 and 26a-2 and 26b-1 and 26b-2 (Figure 12 shows the inner circumferential surface 24a and circumferential end faces 26a-1 and 26a-2 of the outer mold member 22a, but only a part of the inner circumferential surface 24b of the outer mold member 22b is shown, and the reference numeral for the unshown part of the outer mold member 22b is shown in parentheses after the reference numeral for the corresponding part of the outer mold member 22a). As can be understood by referring to Figure 7 together with Figure 12, the inner circumferential surfaces 24a and 24b work together to define the outer circumferential and lower surfaces of the bottom wall 114 of the mouth / neck member 104 and the outer circumferential surface of the mounting wall 118. The inner circumferential surfaces 24a and 24b also define the outer circumferential surface of the hanging wall 116 via the pouch 102. The circumferential end surfaces 26a-1 and 26b-1 abut each other, and the circumferential end surfaces 26a-2 and 26b-2 also abut each other. Shallow recesses 28a-1 and 28a-2 and 28b-1 and 28b-2 are provided on each of the circumferential end surfaces 26a-1 and 26a-2 and 26b-1 and 26b-2, respectively, to receive the side seal portions 108a and 108b of the pouch 102.

[0023] As shown in Figure 7, the injection molding apparatus configured according to the present invention further includes an insert jig 30 that is detachably connected to the base end face 12 of the inner mold member 8. Referring to Figures 13 to 16 in conjunction with Figure 7, the insert jig 30 has a front end face 32 and an outer peripheral surface 34 that hangs down from the outer peripheral edge of the front end face 32. The front end face 32 of the insert jig 30 corresponds to the base end face 12 of the inner mold member 8, and the tip portion 36 of the outer peripheral surface 34 of the insert jig 30 corresponds to the inner peripheral surface of the opening end of the pouch 102. In the illustrated embodiment, the outer peripheral edge of the front end face 32 of the insert jig 30 is circular, the tip portion 36 of the outer peripheral surface 34 of the insert jig 30 is cylindrical, and the rear end portion 38 of the insert jig 30 is a frustoconical shape with an outer diameter that gradually increases toward the tip. If desired, the rear end portion 38 may be a conical shape with an outer diameter that gradually increases toward the tip. Two restrained projections 40a and 40b are provided on the tip surface 32 of the insert jig 30. The insert jig 30 is detachably connected to the inner mold member 8 by the restrained projections 40a and 40b being releasably restrained by the restraining mechanisms 21a and 21b of the inner mold member 8. The restrained projections 40a and 40b are made of metal, and as shown in Figure 7, their base ends are held by a holder embedded in the tip member, which will be described later, and their tips are exposed from the tip member. Since the tips of the restrained projections 40a and 40b are releasably restrained by the restraining mechanisms 21a and 21b, the shape of the tips of the restrained projections 40a and 40b is a required shape corresponding to the restraining mechanisms 21a and 21b, and the diameter gradually increases from the base end to the tip end. An annular groove 42 is formed along the outer circumference of the outer edge of the tip surface 32 of the insert jig 30. The longitudinal cross-sectional shape of the annular groove 42 is a trapezoidal shape that corresponds to the longitudinal cross-sectional shape of the annular projection 14 formed on the base end face 12 of the inner mold member 8. When the annular projection 14 of the inner mold member 8 fits into the annular groove 42 of the insert jig 30, radial movement of the insert jig 30 relative to the inner mold member 8 is prevented when the insert jig 30 is connected to the inner mold member 8.

[0024] In the illustrated embodiment, two restraining mechanisms and two restrained projections were provided, but it is sufficient to have at least one of each, and therefore three or more of each may be provided. If multiple restrained projections and restraining mechanisms are provided, the inner mold member 8 can firmly restrain the insert jig 30. When one restraining mechanism and one restrained mechanism are arranged on the central axis of the inner mold member 8 and the insert jig 30, it is preferable to provide a rotation-preventing means to prevent the insert jig 30 from rotating around the central axis relative to the inner mold member 8. The rotation-preventing means may be configured by fitting a recess and a protrusion provided at an eccentric position with respect to the central axis of the base end face 12 of the inner mold member 8 and the tip face 32 of the insert jig 30. When one restraining mechanism and one restrained mechanism are positioned eccentrically with respect to the central axis of the inner mold member 8 and the insert jig 30, that is, when either the restraining mechanism 21a and the restrained projection 40a, or the restraining mechanism 21b and the restrained projection 40b in the illustrated embodiment are omitted, the annular projection 14 and the annular groove 42 restrict the insert jig 30 from moving laterally relative to the inner mold member 8, and the pair of restraining mechanisms and restrained projections can be configured as the rotation-preventing means.

[0025] As clearly shown in Figure 7, the insert jig 30 includes a tip member 44, an intermediate member 45, and a rear end member 46 stacked vertically, which are fastened together by appropriate fasteners such as bolts (not shown). The tip member 44 and the intermediate member 45 define the tip portion 36 of the insert jig 30, and the rear end member 46 defines the rear end portion 38 of the insert jig 30. The tip member 44 and the intermediate member 45 are short cylindrical shapes with the same outer diameter, thereby defining a cylindrical circumferential wall at the tip portion 36 of the outer circumferential surface 34 of the insert jig 30. Two circumferentially extending arc-shaped openings 48a and 48b are formed in this circumferential wall at equal intervals in the circumferential direction. Both arc-shaped openings 48a and 48b are formed by cutting out a substantially rectangular shape from the outer circumferential surface of the intermediate member 45 along its entire axial length. Furthermore, the arc-shaped openings 48a and 48b are equipped with adjustment members 50a and 50b, each having an outer surface that is an arc shape corresponding to the outer surface of the peripheral wall, so as to be movable between a protruding position in which the outer surface protrudes radially outward from the outer surface of the peripheral wall and a retracted position in which the outer surface retracts radially inward from the outer surface of the peripheral wall. In Figure 16, the adjustment member 50a is shown with a solid line in the retracted position and with a dashed line showing the protruding end face in the protruding position. The bottom surfaces of the arc-shaped openings 48a and 48b are formed with minute protrusions 51a and 51b that protrude toward the respective openings, and the adjustment members 50a and 50b come into contact with the minute protrusions 51a and 51b in the retracted position. The adjustment members 50a and 50b are equipped with elastic members 52 that elastically deviate to the protruding position. As can be understood by referring to Figure 16, locking projections 54a-1 and 54a-2 are formed at the entrance of the arc-shaped opening 48a, projecting circumferentially inward from both sides of the intermediate member 45, and locking projections 56a-1 and 56a-2 are formed on both sides of the adjustment member 50a, projecting outward. The locking projections 56a-1 and 56a-2 are locked by the locking projections 54a-1 and 54a-2, preventing the adjustment member 50a from protruding radially outward beyond its protruding position.Similarly, locking projections 54b-1 and 54b-2 are formed at the entrance of the arc-shaped opening 48b, projecting circumferentially inward from both sides of the intermediate member 45, and locking projections 56b-1 and 56b-2 are formed on both sides of the adjustment member 50b, projecting outward. The locking projections 56b-1 and 56b-2 are locked by the locking projections 54b-1 and 54b-2, preventing the adjustment member 50b from protruding radially outward beyond its protruding position. As shown in Figure 7, holders 57a and 57b for holding the restrained projections 40a and 40b are embedded in the tip member 44. Furthermore, through holes with a circular cross-section that penetrate axially are connected on the central axis of the tip member 44, the intermediate member 45, and the rear end member 46.

[0026] Referring to Figures 17 and 7, when molding the mouth and neck member 104 using the injection molding apparatus of the present invention, first, the opening end of the pouch 102 is fitted into the insert jig 30 from its rear end, causing the opening end 106 of the pouch 102 to protrude beyond the front end surface 32 of the insert jig 30. In the state where the opening end of the pouch 102 is fitted into the insert jig 30, the inner circumferential surface of the opening end of the pouch 102 is pushed outward radially due to the arrangement of adjustment members 50a and 50b on the outer circumferential surface 34 of the insert jig 30, which are elastically biased to the protruding position by the elastic member 52. Then, with the pair of outer mold members 22a and 22b in the open position, the insert jig 30 together with the pouch 102 is connected to the inner mold member 8 by bringing the front end surface 32 of the insert jig 30 into contact with the base end surface 12 of the inner mold member 8. Thus, the open end of the pouch 102 is fitted onto the lower end of the main part 8a and the protruding part 8b of the inner mold member 8. When the open end of the pouch 102 is fitted onto the lower end of the main part 8a and the protruding part 8b of the inner mold member 8, as described above, the inner circumferential surface of the open end of the pouch 102 is pushed outward in the radial direction, which prevents the open end 106 of the pouch 102 from coming into contact with the base end surface 12 of the inner mold member 8 and collapsing radially inward. Subsequently, as shown in Figure 7, the pair of outer mold members 22a and 22b are moved to the closed position, and the upper ends of the side seal portions 108a and 108b of the pouch 102 are positioned within the recesses 28a-1 and 28a-2 and 28b-1 and 28b-2 in the circumferential end faces 26a-1 and 26a-2 and 26b-1 and 26b-2 of the pair of outer mold members 22a and 22b, and are tightly gripped. The lower parts of the inner circumferential surfaces 24a and 24b of the pair of outer mold members 22a and 22b are in close contact with the outer circumferential surface of the opening end of the pouch 102. Thus, the pouch 102 is inserted into the mold. Then, molten synthetic resin material is injected from a synthetic resin injection means (not shown) through resin channels 18a and 18b into the molding cavity defined in the mold, and the mouth and neck member 104 is formed.

[0027] In the injection molding apparatus of the present invention, the open end of the pouch 102 is fitted onto an insert jig 30 that has been detached from the inner mold member 8 of the inner mold means in the molding die disposed on the main body of the injection molding apparatus. Thus, the open end of the pouch 102 can be easily and quickly fitted onto the insert jig 30 as required. Subsequently, by connecting the insert jig 30 together with the pouch 102 to the inner mold member 8, the open end of the pouch 102 can be positioned at the required location on the inner mold member 8. Thus, the open end of the pouch 102 can be easily and quickly inserted into the molding die, and the manufacturing efficiency of composite containers can be dramatically improved. Furthermore, if at least two insert jigs 30 are provided (although not shown in the drawings, for convenience, the first insert jig will be denoted as reference numeral 30a and the second insert jig as reference numeral 30b), one insert jig 30a can be connected to the inner mold member 8, and while the neck member 104 is being injection molded, the opening end of the pouch 102 can be fitted onto the other insert jig 30b, thereby further improving the manufacturing efficiency of the composite container.

[0028] Referring to Figures 18 to 24, the injection molding apparatus 2 further includes a support 58. The support 58 has an upper end surface 60 against which the tip surface 32 of the insert jig 30 abuts, an outer peripheral surface 62 hanging down from the outer peripheral edge of the upper end surface 60, a flange surface 64 protruding from the lower end of the outer peripheral surface 62, and an inner peripheral surface 66 hanging down from the inner peripheral edge of the upper end surface 60. In the illustrated embodiment, the upper end surface 60 of the support 58 is annular in shape, with its widthwise central portion extending substantially horizontally, while the outer peripheral edge extends downward toward the radially outward direction, and the inner peripheral edge extends downward toward the radially inward direction. Its longitudinal cross-sectional shape is a trapezoidal shape corresponding to the longitudinal cross-sectional shape of the annular groove 42 formed in the tip surface 32 of the insert jig 30. The outer circumferential surface 62 of the support member 58 is approximately cylindrical in shape, hanging vertically from the outer edge of the upper end surface 60, then sloping radially inward and hanging down, and then hanging vertically again. The inner circumferential surface 66 of the support member 58 is cylindrical in shape, hanging vertically from the inner edge of the upper end surface 60.

[0029] A groove 68 extending in the diametrical direction is provided on the radially inward side of the outer circumferential surface 62 of the support member 58. The groove 68 is defined between a pair of side walls 70a and 70b, both of which are connected to the inner circumferential surface 66 of the support member 58. Each of the pair of side walls 70a and 70b is a flat plate shape that stands upright in the vertical direction and extends linearly in the diametrical direction, and is parallel to each other. Locking protrusions 72a and 72b are formed on the inner surface of the upper end of each of the pair of side walls 70a and 70b, respectively. The locking protrusions 72a and 72b extend over the entire diametrical direction.

[0030] The support member 58 is also provided with two side seal receiving gaps 74a and 74b located radially outward from the outer peripheral surface 62 and extending axially. The two side seal receiving gaps 74a and 74b are provided one on each side in the diametrical direction, corresponding to the two side seal portions 108a and 108b of the pouch 102. The side seal receiving gaps 74a and 74b are defined between a pair of upright columns 76a-1 and 76a-2 and 76b-1 and 76b-2, respectively, which rise upward from the flange surface 64 and are close to each other in the circumferential direction. The cross-sectional shape of each of the pair of upright columns 76a-1 and 76a-2 and 76b-1 and 76b-2, excluding their tips, is approximately square, but the tips have a square pyramidal shape in which the cross-sectional area decreases towards the top. Each of the tips of the pair of upright columns 76a-1 and 76a-2, and 76b-1 and 76b-2, has its opposing surfaces and radially inward surfaces inclined outward toward upward, and these surfaces constitute the guide surfaces 78a-1 and 78a-2, and 78b-1 and 78b-2. The surfaces of each of the tips of the pair of upright columns 76a-1 and 76a-2, and 76b-1 and 76b-2, other than the guide surfaces 78a-1 and 78a-2, and 78b-1 and 78b-2, extend linearly toward upward.

[0031] Next, the process of inserting the insert jig 30 and the pouch 102 into the mold after fitting the open end of the pouch 102 into the insert jig 30 using the support 58 will be described. In this process, first, the tip surface 32 of the insert jig 30 is brought into contact with the upper end surface 60 of the support 58 which is placed on a table, and the insert jig 30 is attached to the support 58. At this time, the restrained projections 40a and 40b arranged on the tip surface 32 of the insert jig 30 enter into the groove 68 arranged in the support 58, thereby restricting the angular position of the insert jig 30 relative to the support 58. Furthermore, the restrained projections 40a and 40b, which have the required shape, elastically overcome the locking protrusions 72a and 72b formed on each of the pair of side walls 70a and 70b that define the groove 68, and are locked together to their respective lower surfaces, so that the insert jig 30 is stably supported by the support 58. When the insert jig 30 is mounted on the support member 58, the tip 36 of the outer peripheral surface 34 of the insert jig 30 and the outer peripheral surface 62 of the support member 58 define a continuous cylindrical outer peripheral surface. This continuous outer peripheral surface corresponds to the inner peripheral surface of the opening end of the pouch 102. Subsequently, with the insert jig 30 mounted on the support member 58, the opening end of the pouch 102 is fitted onto the insert jig 30 and the support member 58 from the rear end side of the insert jig 30, causing the opening end 106 of the pouch 102 to contact the flange surface 64 of the support member 58. In Figures 23 and 24, the pouch 102 is shown by a dashed line. When fitting the opening end of the pouch 102 onto the insert jig 30 and the support member 58, the side seal portions 108a and 108b of the pouch 102 are received within the side seal portion receiving gaps 74a and 74b, respectively. The side seal portions 108a and 108b of the pouch 102 are smoothly guided into the side seal portion receiving gaps 74a and 74b due to the presence of guide surfaces 78a-1 and 78a-2 and 78b-1 and 78b-2 formed on the tips of the pair of upright columns 76a-1 and 76a-2 and 76b-1 and 76b-2. Next, the insert jig 30 and the pouch 102 are detached from the support 58 as a single unit, and then the insert jig 30 together with the pouch 102 is connected to the inner mold member 8 by bringing the tip surface 32 of the insert jig 30 into contact with the base end surface 12 of the inner mold member 8, thereby inserting the pouch 102 into the mold.Even after the insert jig 30 and the pouch 102 have been detached from the support 58 as a single unit, the outer circumferential surface of the insert jig 30 is in close contact with the inner circumferential surface of the pouch 102 because the outer circumferential surface of the insert jig 30 is in close contact with the inner circumferential surface of the pouch 102 due to the adjustment members 50a and 50b being elastically biased to protruding positions by the elastic member 52 on the outer circumferential surface 34 of the insert jig 30.

[0032] Although preferred embodiments of the injection molding apparatus of the present invention have been described in detail above with reference to the attached drawings, the present invention is not limited to the above embodiments, and further modifications are possible within the scope of the present invention. For example, in the illustrated embodiment, the neck member 104 injected by the injection molding apparatus of the present invention included a mounting wall 118, but this may be omitted. In the case of a neck member in which the mounting wall 118 is omitted, the neck member is sealed by attaching paper or film to the upper surface of the bottom wall, etc. Also, in the illustrated embodiment, the pouch 102 had two side seal portions 108a and 108b, but such side seal portions may not exist. If side seal portions do not exist, it is naturally not necessary to provide a gap for receiving the side seal portions in the support. Furthermore, in the composite container of the illustrated embodiment, the inner surface of the opening end of the pouch was joined to the outer surface of the hanging wall of the neck member, but it is also possible to have a form in which the outer surface of the opening end of the pouch is joined to the inner surface of the hanging wall of the neck member. In the case where the outer surface of the opening end of the pouch is joined to the inner surface of the hanging wall of the neck member, the inner molding means includes an inner mold member that defines at least the outer surface of the hanging wall and the outer surface of the bottom wall of the neck member. In the illustrated embodiment, the base end surface 12 of the inner mold member 8 was facing vertically downward, but it may be facing horizontally or vertically upward. Similarly, with respect to the support member 58, in the illustrated embodiment, the support member 58 was placed on a base, i.e., positioned so that the flange surface 64 faced upward, but the support member 58 may be fixed to any wall, and therefore the flange surface 64 is not necessarily positioned to face only upward. [Explanation of Symbols]

[0033] 2: Injection molding equipment 8: Inner mold member (inner molding means) 12: Base end face (of the inner mold member) 22a and 22b: Outer mold member (outer mold means) 30: Insert jig 32: (The) tip surface of the insert fixture 34: Outer surface (of the insert fixture) 100: Composite container 102: Pouch 104: Oral and cervical member 106: (Pouch) Open end 114: Bottom wall 116: Hanging wall

Claims

1. An injection molding apparatus for manufacturing a composite container composed of a pouch and a neck member, by inserting the open end of a synthetic resin film pouch and injection molding a synthetic resin neck member having a ring-shaped bottom wall that abuts against or is close to the open end of the pouch and a tubular hanging wall that hangs down from the bottom wall and is joined to the inner or outer circumferential surface of the open end of the pouch, The molding die comprises an inner molding means and an outer molding means, The inner molding means includes an inner mold member that defines at least the inner or outer surface of the hanging wall and the inner or outer surface of the bottom wall of the neck member, Furthermore, the inner mold member is equipped with an insert jig that is detachably connected to the base end face, The insert jig has a tip surface and an outer peripheral surface hanging down from the outer peripheral edge of the tip surface, the tip surface of the insert jig corresponds to the base end surface of the inner mold member, and the tip portion of the outer peripheral surface of the insert jig corresponds to the inner peripheral surface of the opening end of the pouch. The opening end of the pouch is fitted into the insert jig from its rear end, so that the opening end of the pouch protrudes beyond the front surface of the insert jig, and then the insert jig together with the pouch is connected to the inner mold member by bringing the front surface of the insert jig into contact with the base end surface of the inner mold member, thereby inserting the pouch into the mold. An injection molding apparatus characterized by the following.

2. The injection molding apparatus according to claim 1, comprising at least two insert jigs, one of which is connected to the inner mold member, and the other insert jig can be fitted with the opening end of the pouch while the neck member is being injection molded.

3. Furthermore, the support includes an upper end surface against which the tip surface of the insert jig abuts, an outer peripheral surface hanging down from the outer peripheral edge of the upper end surface, and a flange surface protruding from the lower end of the outer peripheral surface. When the tip surface of the insert jig is brought into contact with the upper end surface of the support and the insert jig is mounted on the support, the tip portion of the outer peripheral surface of the insert jig and the outer peripheral surface of the support define a continuous cylindrical outer peripheral surface, and this continuous outer peripheral surface corresponds to the inner peripheral surface of the opening end of the pouch. With the insert jig mounted on the support, the open end of the pouch is fitted onto the insert jig and the support from the rear end of the insert jig, bringing the open end of the pouch into contact with the flange surface of the support, then the insert jig and the pouch are detached from the support as a single unit, and thereafter the insert jig together with the pouch is connected to the inner mold member by bringing the front surface of the insert jig into contact with the base end surface of the inner mold member, thereby inserting the pouch into the molding die. The injection molding apparatus according to claim 1 or 2.

4. The injection molding apparatus according to claim 1 or 2, wherein at least one restrained projection is provided on the tip surface of the insert jig, and at least one restraining mechanism is provided on the base end surface of the inner mold member for receiving and releasing the restrained projection, and the insert jig is detachably connected to the inner mold member by the releasely restrained projection being restrained by the restraining mechanism.

5. The injection molding apparatus according to claim 3, wherein the pouch has at least one side seal portion extending from the open end, the support is provided with at least one side seal portion receiving gap located radially outward from the outer surface and extending axially, and when the open end of the pouch is fitted into the insert jig and the support with the insert jig mounted on the support, the side seal portion of the pouch is received within the side seal portion receiving gap.

6. The injection molding apparatus according to claim 3, wherein the upper end surface of the support is ring-shaped, a groove extending in the diametrically is provided on the radially inward side of the outer circumferential surface of the support, and at least one restrained projection is provided on the tip surface of the insert jig, and when the insert jig is mounted on the support, the restrained projection enters the groove, thereby restricting the angular position of the insert jig relative to the support.

7. The injection molding apparatus according to claim 1 or 2, wherein the opening end of the pouch is cylindrical, at least the tip of the outer circumferential surface of the insert jig is defined by a cylindrical circumferential wall, at least two circumferentially extending arc-shaped openings are formed in the circumferential wall of the insert jig at equal intervals in the circumferential direction, and each of the arc-shaped openings is provided with an adjustment member having an outer circumferential surface that is arc-shaped, corresponding to the outer circumferential surface of the circumferential wall, which is movable between a protruding position in which the outer circumferential surface protrudes radially outward from the outer circumferential surface of the circumferential wall and a retracted position in which the outer circumferential surface retracts radially inward from the outer circumferential surface of the circumferential wall, and each of the adjustment members is provided with an elastic member that elastically deviates to the protruding position.

8. The injection molding apparatus according to claim 1 or 2, wherein the outer periphery of the tip surface of the insert jig is circular, the tip portion of the outer periphery of the insert jig is cylindrical, and the rear end of the insert jig is conical or frustoconical in shape, with the outer diameter gradually increasing towards the tip.

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