JP2010168068A - Packaging container and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maintain a container part in a closed condition or an opened condition without an artificial external force and to prevent a lid part from being fixed in a bent back condition relative to the container part. <P>SOLUTION: The container part 2, the lid part 3 and a hinge part 4 of this packaging container 1 are integrally made of a foamed synthetic resin sheet W. The hinge part 4 has a turning shaft section 4a for turnably supporting the lid part 3 relative to the container part 2. The turning shaft section 4a is formed thin by partially forming the sheet W non-foaming. A manufacturing method of the container 1 structured in this way is also provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a packaging container having a container part, a cover part and a hinge part integrally formed from a foamed synthetic resin sheet, and a method for manufacturing the same.

  As this type of packaging container, a container part, a lid part that opens and closes the container part, and a hinge part that rotatably connects the lid part to the container part are integrally formed from the foamed synthetic resin sheet by press molding. What is formed is known. Moreover, what was formed in the thin-wall shape by compressing and thinning in the case of press molding is known as a hinge part (for example, refer patent document 1).

JP 2001-301735 A (paragraph number 0006, FIG. 6)

  However, in the packaging container, since the foamed synthetic resin sheet of the hinge portion is compressed and thinned, each bubble inside is crushed and formed into a flat shape. Although a high hinge part can be obtained, the force to return to the original shape remains strong. For this reason, after the lid is rotated from the open state to the closed state with respect to the container portion, if the force for maintaining the closed state is removed, the lid portion is immediately rotated to the original open state. Will end up. That is, there is a problem in that the lid portion is immediately opened unless an artificial external force is applied to the lid portion to keep it closed by a rubber band or an adhesive tape.

  Moreover, by compressing and thinning the foamed synthetic resin sheet of the hinge portion, the lid portion may be warped toward the closing side or the opening side with respect to the container portion. If warping occurs in this way, it may interfere with the process of inserting food into the container, etc., so measures such as stacking a plurality of completed packaging containers and leaving them for about a day may be taken. It was necessary to remove the warping by taking it.

  The present invention has been made in view of the above circumstances, and can maintain the lid in a closed state and an open state with respect to the container without applying artificial external force, and the lid is It is an object of the present invention to provide a packaging container having a hinge part that is not fixed in a warped state with respect to the container part, and a method for manufacturing the same.

In order to solve the above-mentioned problem, the invention described in claim 1 includes a container part, a lid part that opens and closes the container part, and a hinge part that rotatably connects the lid part to the container part. , A packaging container in which these container part, lid part and hinge part are integrally formed from a foamed synthetic resin sheet,
The hinge portion has a rotation support shaft portion for rotatably supporting the lid portion with respect to the container portion, and the rotation support shaft portion is a part of the foamed synthetic resin sheet. It is characterized in that it is formed into a thin wall by non-foaming.

  According to a second aspect of the present invention, in the first aspect of the present invention, the hinge portion is a plane portion that connects the lid portion that is 180 degrees open from the closed state of the container portion and the container portion. In addition, each of the concave strips has a cross-section from a surface corresponding to the inner surface of the lid portion in the flat surface portion. It is formed in a V-shaped concave shape, and the rotation support shaft portion is formed in a valley bottom portion of each concave stripe portion.

  According to a third aspect of the present invention, in the first aspect of the invention, the hinge portion is a plane portion that connects the lid portion that is 180 degrees open from the closed state of the container portion and the container portion. In addition, the groove portion is configured to include a single groove portion extending linearly, and the groove portion has a V-shaped cross section from a surface on the side corresponding to the outer surface of the lid portion in the flat surface portion. It is formed in a concave shape, and the rotation support shaft part is formed in a valley bottom part of the concave line part.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the rotating support shaft portion is a mold clamp when the container portion, the lid portion and the hinge portion are press-molded. It is characterized by being formed by concentrating a force on a part of the foamed synthetic resin sheet and applying a high pressure to the part.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the rotating support shaft portion is a first for press-molding the container portion, the lid portion, and the hinge portion. A protruding strip portion provided so as to protrude from the inner surface of one of the molding die and the second molding die; and an inner surface portion of the other molding die of the first molding die and the second molding die. Then, a part of the foamed synthetic resin sheet is sandwiched, and the clamping force when press-molding with the first mold and the second mold is concentrated on a part of the foamed synthetic resin sheet. It is characterized by being formed by applying a high pressure to.

  The invention according to claim 6 is the invention according to claim 5, wherein the convex mold part has a pointed part protruding in a V-shaped cross section, and the pointed part is an inner surface part of the other mold. It is characterized by being directed to.

  The invention according to claim 7 is the invention according to claim 5 or 6, wherein the foamed synthetic resin sheet is inserted into the gap between the convex mold part and the inner surface part of the other mold. In the state where the first mold and the second mold are closed to press-mold the container part, the lid part, and the hinge part, it is set to 0 to 0.01 mm. It is said.

  The invention according to claim 8 is a method for producing the packaging container according to any one of claims 1 to 7, wherein a foamed synthetic resin sheet is inserted between the first mold and the second mold. Then, after closing the first mold and the second mold, by applying a clamping force to these molds, the foamed synthetic resin sheet is heated to a predetermined moldable temperature, and the container part and the lid part. And forming the hinge part integrally, concentrating the clamping force on a part of the hinge part, and applying a high pressure to the part, thereby forming a thin-walled coil that is non-foamed on the hinge part. It is characterized by forming a moving support shaft.

  According to the first aspect of the present invention, since the rotation support shaft portion of the hinge portion is formed in a thin shape by non-foaming of the foamed synthetic resin sheet, the lid portion is almost resistant to the rotation support shaft portion. It can rotate without. That is, the rotating support shaft portion becomes extremely thin due to non-foaming, and the cross-sectional secondary moment (around the center of the rotating support shaft portion), which is one element of bending rigidity, becomes extremely small, so that it is almost resistant to resistance. The container part can be opened and closed by rotating the lid part. Therefore, the lid can be kept closed or open with respect to the container by only gravity acting on the lid without applying any artificial external force. In addition, the lid is not fixed in a state where the lid is warped with respect to the container.

  For this reason, for example, in a line for storing food in a packaging container, food can be put into the container part while keeping the lid part open with respect to the container part. After charging, the container part can be easily closed by the lid part. And after closing a container part with a cover part, the said packaging container can be sent to a sealing process, for example, maintaining the closed state, without applying any artificial external force. Therefore, since the process and equipment for maintaining the container part closed with the lid part are not required, the process for packaging food and the like is simplified, and the cost required for the packaging equipment can be reduced. . Further, since the lid portion is not fixed in a state where it is warped with respect to the container portion, it is possible to save labor and time for removing the warping.

  Further, since the rotation support shaft portion becomes a solid thin film by non-foaming, there is an advantage that the rotation support shaft portion has high durability enough to withstand rotation.

  According to the second aspect of the present invention, the hinge portion extends linearly in parallel with each other on the flat portion connecting the lid portion and the container portion that are opened 180 degrees from the closed state of the container portion. Each groove is formed in a concave shape with a V-shaped cross section from the surface corresponding to the inner surface of the lid portion in the flat surface, and the rotation support shaft portion Since it is formed on the valley bottom of the recess, when the lid is rotated to close the container, the flat portions of a predetermined thickness located on the left and right of the two recesses hit each other. It is possible to prevent the rotation from being obstructed. Therefore, the lid can be reliably rotated to the position where the container is completely closed.

  According to the third aspect of the present invention, the hinge portion is a single concave portion extending linearly on the flat portion that connects the lid portion that is 180 degrees open from the closed state of the container portion and the container portion. It has a configuration including a strip portion, and the concave strip portion is formed in a concave shape having a V-shaped cross section from the surface corresponding to the outer surface of the lid portion in the flat portion, and the rotation support shaft portion is a valley bottom of the concave strip portion. As the lid is turned to close the container, it prevents the flat parts with a predetermined thickness located on the left and right of the hinge from hitting each other and obstructing the rotation. can do. Therefore, the lid can be reliably rotated to the position where the container is completely closed.

  According to the fourth aspect of the present invention, the clamping force when the container part, the lid part, and the hinge part are press-molded is concentrated on a part of the foamed synthetic resin sheet, and a high pressure is applied to the part. Thus, the rotation support shaft portion is formed, and therefore, the rotation support shaft portion can be formed efficiently and easily in the process of press forming the container portion, the lid portion, and the hinge portion.

  According to invention of Claim 5, it provided so that it might protrude from the inner surface of one shaping | molding die among the 1st shaping | molding die for press-molding a container part, a cover part, and a hinge part. A part of the foamed synthetic resin sheet is sandwiched between the protruding strip portion and the inner surface portion of the other molding die of the first molding die and the second molding die, and press-molded by the first molding die and the second molding die. Since the rotational support shaft portion is formed by concentrating the clamping force at the time on a part of the foamed synthetic resin sheet and applying a high pressure to the part, it is specified by the convex mold portion The rotation support shaft portion can be accurately formed at the position of the rotation support shaft portion. Further, by forming the convex mold part and the inner surface part of the other mold corresponding to the convex mold part with an excellent material such as a high hardness, the cost of the first mold and the second mold can be reduced. The durability of the mold can be improved while suppressing the rise.

  According to the invention described in claim 6, the protruding strip mold portion has a pointed end portion that protrudes in a V-shaped cross section, and the pointed end portion is directed to the inner surface portion of the other mold. The foamed synthetic resin sheet can be sandwiched between the very narrow linear portion of the tip portion and the inner surface portion of the other mold. Therefore, extremely high pressure can be applied to the foamed synthetic resin sheet in a concentrated manner in a linear manner, so that it is possible to easily form a rotating support shaft portion that is not foamed by the linear high pressure generated at that time. Can do. In addition, since the protruding strip portion has a shape having a pointed portion protruding in a V-shaped cross section, it is possible to reduce resistance generated when the protruding strip portion is pushed into the foamed synthetic resin sheet.

  According to invention of Claim 7, in the state which closed the 1st shaping | molding die and the 2nd shaping | molding die in order to press-mold a container part, a cover part, and a hinge part, without inserting a foaming synthetic resin sheet | seat. Since the gap between the ridge mold portion and the inner surface portion of the other mold is set to 0 to 0.01 mm, it is interposed between the ridge mold portion and the inner surface of the other mold. An extremely high pressure can be applied to the foamed synthetic resin sheet, and an extremely thin rotating support shaft portion that is non-foamed can be formed at the high-pressure portion.

  According to the manufacturing method of the packaging container according to the invention of claim 8, the foamed synthetic resin sheet is inserted between the first mold and the second mold, and the first mold and the second mold are used. After closing, by applying a clamping force to these molds, the container part, the lid part and the hinge part are integrally molded from the foamed synthetic resin sheet heated to a predetermined moldable temperature. Then, the mold clamping force can be concentrated on a part of the hinge part, and a thin-walled rotating support shaft part that is not foamed on the part can be formed. Accordingly, in the process of integrally forming the container part, the lid part and the hinge part from the foamed synthetic resin sheet as a raw material, it is possible to efficiently form a hinge part having a non-foamed thin-walled rotating shaft part. it can.

It is a perspective view of the packaging container shown as one embodiment of this invention. It is sectional drawing which shows the 1st shaping | molding die and 2nd shaping | molding die which shape | mold the packaging container and this packaging container. It is a figure which shows the principal part of the 1st shaping | molding die and 2nd shaping | molding die which shape | mold the hinge part of this packaging container, and this hinge part, (a) is sectional drawing which shows a mold open state, (b) is It is sectional drawing which shows a mold clamping state, (c) is sectional drawing which shows the state closed without inserting a foaming synthetic resin sheet, (d) is a principal part which shows a concave part and a rotation support shaft part. FIG. It is a figure which shows the packaging container, Comprising: (a) is sectional drawing which shows the state after opening 180 degree | times from the state which closed the cover part completely with respect to the container part, (b) is a container in a cover part. It is sectional drawing which shows the state after rotating a predetermined angle to the closing direction with respect to a part, (c) is sectional drawing which shows the state after closing a container part completely with a cover part. It is a figure which shows the hinge part of the packaging container, Comprising: (a) is sectional drawing which shows the state after opening 180 degree | times from the state which closed the cover part completely with respect to the container part, (b) is a cover It is sectional drawing which shows the state after rotating a predetermined angle in the direction which closes a part with respect to a container part, (c) is sectional drawing which shows the state after closing a container part completely with a cover part. It is explanatory drawing which shows the manufacturing apparatus of the packaging container. It is a figure which shows the other example of the hinge part of the packaging container, Comprising: (a) is sectional drawing which shows a mold open state, (b) is sectional drawing which shows a mold clamping state, (c) is foaming It is sectional drawing which shows the state which closed the mold, without inserting a synthetic resin sheet, (d) is sectional drawing which shows the state after opening 180 degree | times from the state which closed the cover part completely with respect to the container part. (E) is sectional drawing which shows the state after rotating a predetermined angle in the direction which closes a cover part with respect to a container part, (f) shows the state after closing a container part completely with a cover part. It is sectional drawing.

  An embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the packaging container 1 shown in this embodiment includes a container part 2, a lid part 3 that opens and closes an opening part of the container part 2, and the lid part 3 rotates to the container part 2. The container portion 2, the lid portion 3, and the hinge portion 4 are integrally formed from the foamed synthetic resin sheet W.

  The foamed synthetic resin sheet W is widely used as a PSP (polystyrene paper) sheet. The container portion 2 has a flange portion 21 formed in a planar shape with a predetermined width around the container portion 2, and a fitting convex portion 22 formed in a raised state with respect to the flange portion 21 and constituting a quadrangular opening. have. The lid 3 is configured such that an inner peripheral surface 3a along the rectangular opening is fitted to the outer peripheral surface 22a of the fitting convex portion 22 of the container portion 2 and has a predetermined width around the opening. It has the collar part 31 formed in planar shape. As shown in FIG. 4 (c), the lid 3 has its inner circumferential surface 3 a fitted to the outer circumferential surface 22 a of the fitting convex portion 22, and its collar 31 is brought into contact with the collar 21 of the container 2. By making it into the state made into the said, the said container part 2 is made into the state closed completely. And the container part 2 and the lid | cover part 3 are the states closed completely by the fitting force of the predetermined magnitude | size produced by fitting with the outer peripheral surface 22a and the inner peripheral surface 3a in the state closed completely. To be maintained. However, the fitting force is small enough that a normal person can easily and smoothly open the lid 3 from the container 2. The hinge portion 4 has a rotation support shaft portion 4a for rotatably supporting the lid portion 3 with respect to the container portion 2.

  Further, as shown in FIG. 1, the hinge portion 4 includes two concave strip portions 4 b that extend linearly in parallel to each other on a flat surface portion 5 that connects the container portion 2 and the lid portion 3. It has become. As shown in FIG. 4 (a), the flat surface portion 5 is opened by rotating 180 degrees around the rotation support shaft portion 4a from a state in which the container portion 2 is completely closed. And the container portion 2 are formed in a planar shape. In the case of this example, the flat surface portion 5 is formed so as to be continuous with the flange portion 21 of the container portion 2 and the flange portion 31 of the lid portion 3. It is formed in a band shape with a width of.

  Each concave strip 4b is formed in a straight line in a direction extending in a strip shape of the flat portion 5, and from the surface on the side corresponding to the inner peripheral surface (inner surface) 3a of the lid portion 3 in the flat portion 5. It is formed in a concave shape with a V-shaped cross section. As shown in FIG. 3D, the left and right inclined surfaces of each concave line portion 4 b are formed so that the angles θ with respect to the perpendicular P of the plane portion 5 are equal. The angle θ is preferably set to 45 degrees or more and 55 degrees or less (in this example, it is set to about 50 degrees).

  The rotation support shaft portion 4a is thinned by non-foaming a part of the foamed synthetic resin sheet W, and is formed at the bottom of each recess 4b. The rotating support shaft portion 4a concentrates the clamping force when the container portion 2, the lid portion 3 and the hinge portion 4 are vacuum press-molded (press-molded) on a part of the foamed synthetic resin sheet W, and It is formed by applying a high pressure to the part.

  That is, as shown in FIG. 2, the rotation support shaft portion 4a is one of the first molding die M1 and the second molding die M2 for vacuum press molding the container portion 2, the lid portion 3 and the hinge portion 4. The foamed synthetic resin sheet includes a protruding strip mold portion M1a provided so as to protrude from the inner surface of the first molding die M1 as the molding die and an inner surface portion M2a of the second molding die M2 as the other molding die. A part of W is sandwiched and the clamping force when vacuum press molding is performed by the first molding die M1 and the second molding die M2 is concentrated on a part of the foamed synthetic resin sheet W, and a high pressure is applied to the part. It is formed by acting. In addition, by press-molding with the convex mold part M1a and the inner surface part M2a, the above-mentioned concave strips 4b are also formed at the same time.

  Further, as shown in FIG. 2 and FIGS. 3A and 3B, each protruding line mold portion M1a protrudes from the inner surface of the first forming mold M1 of the protruding block M1b embedded in the first forming mold M1. And has two pointed portions M1c protruding in a V-shaped cross section, and each pointed portion M1c is directed to the inner surface portion M2a of the second mold M2. The tip angle of each tip M1c is set to an angle corresponding to the angle θ described above.

  The inner surface portion M2a is formed by a surface exposed from the inner surface of the second molding die M2 of the holding block M2b embedded in the second molding die M2. The inner surface portion M2a is formed to have the same surface shape as the inner surface around the holding block M2b in the second mold M2.

  As shown in FIG. 3 (c), the gap between the convex mold part M1a and the inner surface part M2a is the same as the first mold M1 and the first mold for vacuum press molding without inserting the foamed synthetic resin sheet W. 2 In a state where the molding die M2 is closed (a state before mold clamping), the thickness is set to 0 to 0.01 mm. That is, the gap is preferably set to 0 mm basically, but it is necessary to consider a manufacturing dimensional tolerance of about 0.01 mm. If this gap is 0.01 mm or less, the foamed synthetic resin sheet W is extremely deformed by the elastic deformation of the first molding die M1 and the second molding die M2 during clamping, as in the case where the gap is 0 mm. High pressure can be applied. In addition, the hinge part 4 is the structure provided with the plane part 5, the recessed strip part 4b formed in this plane part 5, and the rotation support shaft part 4a.

  In the packaging container 1 configured as described above, the rotation support shaft portion 4a of the hinge portion 4 is formed thin by non-foaming of the foamed synthetic resin sheet W. There is almost no resistance when the lid 3 is rotated. That is, the rotation support shaft portion 4a becomes extremely thin due to non-foaming, and the cross-sectional secondary moment (around the axis of the rotation support shaft portion 4a), which is one element of bending rigidity, becomes extremely small. The container part 2 can be opened and closed by rotating the lid part 3 with almost no resistance. Therefore, the lid 3 can be maintained in a closed state or an open state only by gravity acting on the lid 3 without applying any artificial external force. Moreover, in the open state, it can prevent that the cover part 3 is fixed in the state which curved with respect to the container part 2. FIG. In this example, the closed state is maintained by the holding force due to the fitting, but the lid 3 is maintained in the closed state or the opened state even without the holding force due to the fitting. be able to.

  For this reason, for example, in the line which accommodates food in the packaging container 1, the packaging container 1 can be moved to the food charging step while the lid 3 is kept open with respect to the container part 2. At the same time, after putting food into the container part 2 and closing the container part 2 with the lid part 3, the packaging container 1 is sealed, for example, while maintaining the closed state without applying any external force. Can be sent to. Therefore, since the process and equipment for maintaining the container part 2 in the closed state are not required, the packaging process for food and the like is simplified, and the cost for the packaging equipment can be reduced. In addition, it is possible to save labor and time for removing the warping of the lid 3 with respect to the container 2.

  Further, since the rotation support shaft portion 4a becomes a solid thin film by non-foaming, there is an advantage that the rotation support shaft portion 4a is sufficiently durable to withstand repeated rotation of the lid portion 3. is there.

  Further, the hinge portion 4 has a configuration including two concave portions 4b extending in parallel to the flat portion 5 connecting the lid portion 3 and the container portion 2, and each concave portion 4b is formed by the flat portion 5. 4 is formed in a concave shape with a V-shaped cross section from the surface corresponding to the inner peripheral surface 3a of the lid portion 3, and the rotation support shaft portion 4a is formed at the bottom of each valley portion 4b. And as shown in FIG. 5, when the cover part 3 is rotated in order to close the container part 2, the plane part 5 of the predetermined thickness located in the right and left of the two recessed strip parts 4b may mutually contact. Absent. That is, since the angle θ of the left and right inclined surfaces of each recess 4b is formed to be 45 degrees or more with respect to the perpendicular P of the flat portion 5, as shown in FIGS. 4 (c) and 5 (c). Even if the lid portion 3 is rotated until the container portion 2 is completely closed, the flat portions 5 do not come into contact with each other and become resistance to rotation. Therefore, the lid 3 can be rotated without resistance to a position at which the container 2 is completely closed.

  Then, the rotational support shaft portion 4a is formed by concentrating the clamping force at the time of vacuum press molding on a part of the foamed synthetic resin sheet W and applying a high pressure to the part. Therefore, the rotation support shaft portion 4a can be efficiently and easily formed in the normal forming process of the container portion 2, the lid portion 3 and the hinge portion 4.

  That is, a portion of the foamed synthetic resin sheet W is sandwiched between the protruding strip portion M1a provided so as to protrude from the inner surface of the first molding die M1 and the inner surface portion M2a of the second molding die M2. Since the rotation support shaft portion 4a is formed by concentrating the mold clamping force and applying a high pressure, the rotation support shaft is placed at a predetermined position of the hinge portion 4 specified by the protruding strip mold portion M1a. The part 4a can be formed accurately. Further, by forming the ridge block M1b having the ridge mold portion M1a and the inner surface portion M2a and the holding block M2b with a material having excellent material such as hardness, the cost of the first mold M1 and the second mold M2 can be reduced. The durability of the molds M1 and M2 can be improved while suppressing the rise.

  And since the protruding strip mold portion M1a has a pointed portion M1c protruding in a V-shaped cross section, and the pointed end portion M1c is directed to the inner surface portion M2a of the second mold M2, the pointed portion in the protruding strip mold portion M1a The foamed synthetic resin sheet W can be sandwiched between the extremely narrow linear portion of the portion M1c and the inner surface portion M2a. Accordingly, a very high pressure can be applied to the foamed synthetic resin sheet W in a concentrated manner in a linear manner, and the rotational support extending in a non-foamed linear shape by the linear high pressure generated at that time. The shaft portion 4a can be easily formed. Moreover, since the ridge mold portion M1a has the pointed portion M1c protruding in a V-shaped cross section, the resistance generated when the ridge mold portion M1a is pushed into the foamed synthetic resin sheet W can be reduced. . In addition, since the resistance at the time of pushing the protruding strip part M1a into the foamed synthetic resin sheet W increases as the angle θ increases, the angle θ is preferably set to 55 degrees or less.

  Moreover, in the state which closed the 1st shaping | molding die M1 and the 2nd shaping | molding die M2 without inserting the foaming synthetic resin sheet W, the clearance gap between the protruding item | line mold part M1a and the inner surface part M2a is 0-0. Since it is set to .01 mm, it is possible to generate a very high pressure on the foamed synthetic resin sheet W interposed between the ridge mold part M1a and the inner surface part M2a. A non-foamed and extremely thin rotating support shaft portion 4a can be formed.

  Next, the manufacturing method of the packaging container 1 comprised as mentioned above is demonstrated with reference to FIG. First, a temperature (130 to 150 ° C.) at which the foamed synthetic resin sheet W can be molded by the vacuum press molding apparatus (press molding apparatus) B by sending the foamed synthetic resin sheet W wound in a roll shape to the preheating apparatus A. The heated foamed synthetic resin sheet W is sent to the vacuum press molding apparatus B in which the first molding die M1 and the second molding die M2 are in the mold open state.

  In the vacuum press molding apparatus B, after the foamed synthetic resin sheet W is received between the first mold M1 and the second mold M2 in the mold open state, the first mold M1 and the first mold M1 and the second mold M2 are received by the hydraulic cylinders B1 and B2. 2 After the mold M2 is closed, the mold is further clamped by supplying high-pressure hydraulic oil to the hydraulic cylinders B1 and B2. After the mold clamp state is maintained for a predetermined time, the hydraulic cylinders B1 and B2 perform the first clamping. The mold M1 and the second mold M2 are opened. The foamed synthetic resin sheet W having a plurality of packaging containers 1 molded by the vacuum press molding apparatus B is sent to the next process.

  In the vacuum press molding apparatus B, the mold-clamping force for molding the packaging container 1 is concentrated on a part of the hinge portion 4 and a high pressure is applied to the part, thereby making the non-foamed thin wall shape. The rotating support shaft portion 4a is formed. In addition, although the number of the packaging containers 1 which can be shape | molded at once changes with the magnitude | sizes of the said packaging container 1, it is 1-100 pieces, and in the case of the packaging container 1 of this example, it is about 12-50 pieces. And when shape | molding about 12-50 packaging containers 1 at once, the sum total of the length of the rotation support shaft part 4a formed in linear form will be about 6-12m. The clamping force (pressing force) generated by the hydraulic cylinders B1 and B2 is about 10 to 40 tons (100 to 400 kN).

  Further, while the packaging container 1 is being molded with the first molding die M1 and the second molding die M2, evacuation is performed to suck air from the inner surfaces of the first molding die M1 and the second molding die M2. ing. By this evacuation, the moldability is improved. Further, when the mold is opened after molding, the molded product is subjected to compressed air treatment for blowing air of a predetermined pressure from the inner surface side of each of the molding dies M1 and M2, so that the molded product is made into the first molding die M1 and the second molding die. Separated from M2.

  The foamed synthetic resin sheet W having the molded packaging container 1 is sent to the trimming device C and punched out for each packaging container 1. Although FIG. 6 shows a state in which the packaging containers 1 are punched one by one, a plurality of packaging containers 1 can be punched simultaneously. The punched packaging containers 1 are stacked in a predetermined number and then sent to the next process such as an inspection process. The foamed synthetic resin sheet W after punching the packaging container 1 is sent to the pulverizer D as scrap and pulverized.

  In the manufacturing method of the packaging container 1 configured as described above, the step of heating the foamed synthetic resin sheet W to a moldable temperature in advance, and the heated foamed synthetic resin sheet W is formed into the first molding die M1 and the second molding. The step of inserting between the mold M2, the first mold M1 and the second mold M2 are closed, and then a clamping force is applied to the molds M1 and M1, thereby the container part 2 and the lid part 3 And the process of integrally forming the packaging container 1 composed of the hinge part 4 concentrates the clamping force on a part of the hinge part 4 in a linear manner, and the part is a thin-walled non-foamed part. The rotation support shaft portion 4a can be formed. That is, the rotation support shaft portion 4a extending linearly can be formed by linear high-pressure processing. Accordingly, in the process of integrally forming the container portion 2, the lid portion 3 and the hinge portion 4 from the foamed synthetic resin sheet W as a raw material, the hinge portion 4 having the thin-walled rotation support shaft portion 4a that is not foamed is provided. It can be easily formed.

  In the above-described embodiment, the example in which the hinge portion 4 is configured to have the two concave stripe portions 4b is shown. However, as the hinge portion 4, as shown in FIG. Even if it comprises so that it may have one concave part 4b extended in the straight line in the plane part 5 which connects the cover part 3 of the state opened 180 degree | times from the state which closed the part 2, and the container part 2 Good. In this case, the concave strip portion 4b is formed in a concave shape having a V-shaped cross section from the surface on the side corresponding to the outer surface 3b (see FIGS. 4A and 7D) of the lid portion 3 in the plane portion 5. become. Moreover, the point which the rotation support shaft part 4a is formed in the valley bottom part of the concave line part 4b is the same as that of the example mentioned above. And the convex strip mold part M1a for forming the concave strip part 4b is provided with the convex strip block M1b in the second molding die M2 as shown in FIGS. 7 (a) and 7 (b). The inner surface M2a is provided in the first molding die M1 by providing the holding block M2b in the first molding die M1. Further, the protruding strip portion M1a is configured to have one pointed portion M1c. The tip angle of the tip M1c is preferably set to 10 to 30 degrees at an angle corresponding to the angle θ described above. This is because when the angle θ is less than 10 degrees, the durability of the tip M1c is lowered, and when it is 25 degrees or more, the lid 3 is completely closed as shown in FIG. 7 (f). This is because the angle formed by each inclined surface of the concave strip 4b is 120 degrees or less, and the inclined portion has a sharp shape. Further, as shown in FIG. 7 (c), the gap between the convex strip portion M1a and the inner surface portion M2a is the first molding die M1 for vacuum press molding without inserting the foamed synthetic resin sheet W. In the state where the second mold M2 is closed (the state before the mold clamping), it is set to 0 to 0.01 mm.

  In the packaging container 1 provided with the hinge part 4 which has the one groove part 4b comprised as mentioned above, the groove part 4b is from the surface of the side corresponding to the outer surface 3b of the cover part 3 in the plane part 5. Since it is formed in a concave shape with a V-shaped cross section, and the rotation support shaft portion 4a is formed at the bottom of the valley portion 4b, when the lid portion 3 is rotated to close the container portion 2, FIG. As shown in (f), the plane portions 5 having a predetermined thickness located on the left and right sides of the hinge portion 4 do not hit each other and become a rotation resistance. Therefore, the lid 3 can be rotated to the position where the container 2 is completely closed. In addition, since the number of the concave portions 4b is reduced, the rotational drive shaft 4a can be formed by applying a higher pressure to the foamed synthetic resin sheet W. In other words, even when the clamping force is small, it is possible to mold the non-foamed rotation support shaft portion 4a. Furthermore, since the angle corresponding to the angle θ at the tip M1c can be set to a small angle of 45 degrees or less, the efficiency of concentrating the mold clamping force from the protruding strip mold M1a to the foamed synthetic resin sheet W is improved. Improvements can be made. For this reason, the resistance at the time of pushing the protruding strip mold part M1a into the foamed synthetic resin sheet W can be further reduced.

  Moreover, although the example which used the PSP sheet | seat as the foaming synthetic resin sheet W was shown, as this foaming synthetic resin sheet W, the sheet | seat using another foaming synthetic resin may be sufficient. Further, the example in which the convex mold part M1a and the inner surface part M2a are provided in the first molding die M1 and the second molding die M2 by forming the convex strip block M1b and the holding block M2b, respectively, is shown. However, the first molding die M1 and the second molding die M2 may be directly formed on the first molding die M1 and the second molding die M2 so as to be provided on the first molding die M1 and the second molding die M2.

DESCRIPTION OF SYMBOLS 1 Packaging container 2 Container part 3 Lid part 3a Inner peripheral surface (inner surface)
3b Outer surface 4 Hinge portion 4a Rotating support shaft portion 4b Concave strip portion 5 Planar portion M1 First molding die M1a Convex strip portion M1b Convex strip block M1c Pointed end M2 Second molding die M2a Inner surface portion M2b Holding block A Preheating device B Vacuum press molding equipment (press molding equipment)
W Foamed synthetic resin sheet

Claims (8)

A container part, a lid part that opens and closes the container part, and a hinge part that rotatably connects the lid part to the container part, and the container part, the lid part, and the hinge part are made of a foamed synthetic resin sheet. An integrally formed packaging container,
The hinge portion has a rotation support shaft portion for rotatably supporting the lid portion with respect to the container portion,
The rotating support shaft portion is formed into a thin wall shape by non-foaming a part of the foamed synthetic resin sheet. The hinge portion includes two concave portions extending linearly in parallel to each other on a flat portion connecting the lid portion in a state where the container portion is opened 180 degrees from the closed state and the container portion. It has a configuration with
Each of the concave portions is formed in a concave shape having a V-shaped cross section from a surface corresponding to the inner surface of the lid portion in the flat portion,
The packaging container according to claim 1, wherein the rotation support shaft portion is formed at a valley bottom portion of each concave strip portion. The hinge portion is configured to include a concave portion extending linearly on a flat surface portion connecting the lid portion and the container portion that is opened 180 degrees from a state where the container portion is closed. And
The concave stripe portion is formed in a concave shape having a V-shaped cross section from a surface on the side corresponding to the outer surface of the lid portion in the flat portion,
The packaging container according to claim 1, wherein the rotation support shaft portion is formed at a valley bottom portion of the concave stripe portion.   The rotating support shaft portion concentrates a clamping force when press-molding the container portion, the lid portion, and the hinge portion on a part of the foamed synthetic resin sheet, and applies a high pressure to the part. It is formed by making it the packaging container in any one of Claims 1-3 characterized by the above-mentioned.   The pivot support shaft portion is provided so as to protrude from the inner surface of one of the first molding die and the second molding die for press-molding the container portion, the lid portion, and the hinge portion. A part of the foamed synthetic resin sheet is sandwiched between the protruding mold part and the inner surface part of the other mold of the first mold and the second mold, and the first mold and the second mold It is formed by concentrating the clamping force at the time of press molding with a mold on a part of the foamed synthetic resin sheet, and applying a high pressure to the part. The packaging container in any one.   The packaging container according to claim 5, wherein the convex mold part has a pointed part protruding in a V-shaped cross section, and the pointed part is directed to an inner surface part of the other mold. .   The gap between the convex mold part and the inner surface part of the other mold is used to press-mold the container part, the lid part and the hinge part without inserting the foamed synthetic resin sheet. The packaging container according to claim 5 or 6, wherein the packaging container is set to 0 to 0.01 mm in a state in which the first mold and the second mold are closed. A method for producing the packaging container according to claim 1,
By inserting the foamed synthetic resin sheet between the first mold and the second mold, and then closing the first mold and the second mold and then applying a clamping force to these molds. The container part, the lid part and the hinge part are integrally molded from the foamed synthetic resin sheet heated to a predetermined moldable temperature, and the mold clamping force is concentrated on a part of the hinge part to increase the part. A method for manufacturing a packaging container, characterized in that, by applying pressure, a thin-walled rotating support shaft portion that is non-foamed is formed on the hinge portion.

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