Tube container, mandrel, and method of manufacturing a tube container

Abstract

In the tube container, the radius of curvature of the four corner portions of the sleeve is reduced, and the adhesion strength between the sleeve and the head is secured, and deformation of the sleeve during molding is suppressed. The tube container has a periphery portion (17a) attached to a end portion (13a), and the end portion (13a) extends in a straight line in the axial direction. The periphery portion (17a) has a flange portion (21) attached to the axial cross-section (13c) of the end portion (13a) and an outer periphery portion (22) attached to the inner surface (13d) of the end portion (13a). The head (14) has an annular protrusion (23) protruding downward from the base (15). The outer surface (23a) of the protrusion (23) is attached to the inner surface (13d) of the end portion (13a). On the inner side of the four corner portions (25), the inner surface of the protrusion (23b), which is the inner surface of the protrusion (23), is an inclined surface that extends in a straight line so as to be located radially outward as it goes downward.

Description

Technology Field

[0001] The present invention relates to a tube container, a mandrel, and a method for manufacturing a tube container. Background Technology

[0002] Conventionally, a tube container is known having a tube-shaped sleeve and a head having an inlet that closes the opening of one end of the sleeve, wherein the periphery of the head is fixed to one end of the sleeve (see, for example, Patent Document 1). In the container of Patent Document 1, one end of the sleeve is formed as a curved portion in which the upper end of the sleeve is bent radially inward, and said curved portion is fixed to the periphery of the head. By doing so, the fixation area between one end of the sleeve and the periphery of the head is greatly secured, and high fixation strength is obtained. Prior art literature

[0003] Japanese Patent Publication No. 2003-40293 The problem to be solved

[0004] Meanwhile, regarding the sleeve, a tube container is generally known to have a rectangular shape with four corners when viewed from the axial direction at the part connected to the head. In such tube containers, there are cases where it is desired to reduce the radius of curvature of the four corners according to aesthetic requirements. However, if the radius of curvature of the corners is reduced in a structure in which the curved portion formed in the sleeve is fixed to the head as in the conventional method described above, defects in the shape of the sleeve at the corners are prone to occur during the molding of the tube container; for example, the material of the head may curl inward toward the outside of the sleeve, or wrinkles may form on the sleeve at the curved portions. On the other hand, if the curved portion is not formed in the sleeve, it is difficult to secure the fixation strength between the sleeve and the head.

[0005] In addition, four corners can be formed in the sleeve by inserting a mandrel equipped with four corners for molding into the sleeve, but when inserting the mandrel into the sleeve, the mandrel may get caught on the corners of the sleeve, causing the sleeve to deform. In particular, when the radius of curvature of the four corners of the mandrel is small, the mandrel is prone to getting caught on the corners of the sleeve. Therefore, it is desirable to suppress deformation of the sleeve caused by the mandrel.

[0006] In light of the above, the present invention aims to reduce the radius of curvature of the four corner portions of the sleeve in a tube container while also securing the adhesion strength between the sleeve and the head, and furthermore, to suppress deformation of the sleeve during the molding of the sleeve. means of solving the problem

[0007] A tube container comprises a tube-shaped sleeve, a plate-shaped base, and an inlet portion erected from the base, and a head that closes the opening of one end portion of the sleeve, wherein the periphery portion of the base is fixed to the one end portion, and the sleeve is formed in a square shape having four corner portions when viewed from the head side in the axial direction of the sleeve, wherein the one end portion extends in a straight line in the axial direction of the sleeve, and the periphery portion has a flange portion fixed to the cross-section in the axial direction of the one end portion and an outer periphery portion fixed to the inner circumference portion of the one end portion, and the head has an annular protrusion protruding downward from the base, and the outer circumference portion of the protrusion is fixed to the inner circumference portion of the one end portion below the outer circumference portion, and the inner circumference portion of the protrusion, which is the inner circumference portion of the protrusion, is an inclined surface that extends in a straight line so as to be located radially outward as it goes downward.

[0008] A mandrel used in the manufacture of a tube container comprises a molding corner portion for forming the corner portion, a head molding portion having a shape that follows the head, and a protrusion molding portion formed on the outer periphery of the head molding portion for forming the protrusion, wherein the protrusion molding portion is a straight chamfered portion that follows the inner surface of the protrusion.

[0009] A method for manufacturing a tube container using a mandrel comprises an insertion process of inserting the mandrel into the sleeve through the protrusion forming part, and a molding process of forming the head by forming the material of the head in a cavity formed between the mold and the mandrel while forming the corner part by the molding corner part, and also fixing the periphery part and the protrusion part to the end part. Effects of the invention

[0010] According to the present invention, in a tube container, the radius of curvature of the four corner portions of the sleeve is reduced, and the adhesion strength between the sleeve and the head is secured, and furthermore, deformation of the sleeve during the molding of the sleeve can be suppressed. Brief explanation of the drawing

[0011] FIG. 1 is a side view of a tube container according to a first embodiment of the present invention. Figure 2 is a top view of a tube container. Figure 3 is a cross-sectional view of a tube container. Figure 4 is a drawing illustrating an example of a method for manufacturing a container body. Fig. 5a is a side view of a mandrel. FIG. 5b is a bottom view of the mandrel seen from below. FIG. 6 is an enlarged cross-sectional view of the connection portion between the head and the sleeve in the second embodiment. Specific details for implementing the invention

[0012] [First Embodiment]

[0013] Hereinafter, embodiments of a tube container according to the present invention will be described with reference to the drawings.

[0014] FIG. 1 is a side view of a tube container (10) according to a first embodiment of the present invention. FIG. 2 is a top view of the tube container (10). FIG. 3 is a cross-sectional view of the tube container (10).

[0015] The tube container (10) comprises a container body (11) for holding contents and an unillustrated cap mounted on the container body (11).

[0016] The contents of the tube container (10) are not particularly limited, but the contents are viscous materials such as cosmetics, food, etc.

[0017] The container body (11) is provided with a cylindrical sleeve (13) and a head (14) attached to an axial end (13a) of the sleeve (13).

[0018] The sleeve (13) is a tube formed by cutting a tube body, which is continuously formed by extrusion molding or the like, into a predetermined length in the axial direction. The sleeve (13) is made of synthetic resin.

[0019] As a single unit, the sleeve (13) has an open end (13a) and a other end (not shown) in the axial direction.

[0020] The opening of one end (13a) of the sleeve (13) is closed by the head (14) being fixed to the one end (13a).

[0021] The opening of the other end of the sleeve (13) is closed by fixing the other end by a method such as welding, while the inner surfaces facing each other at the other end are in contact.

[0022] In FIGS. 1 and 3, the tube container (10) is shown in an upright position with the tube container (10) positioned so that the axis (13b) of the sleeve (13) faces upward and downward.

[0023] The sleeve (13) is cylindrical in shape when the tube body is cut, but when connected to the head (14) to form the container body (11), it forms the container body part, which is the main body of the container body (11).

[0024] As shown in FIG. 2, the sleeve (13) is formed in a rectangular shape having four curved corner portions (25) that follow the shape of the head (14) when viewed along the axial direction of the sleeve (13) from the head (14) side. More specifically, the sleeve (13) is a rectangular body when viewed along the axial direction. The axis (13b) is located at the center of the rectangular sleeve (13).

[0025] When viewed axially from the head (14), the basic shape of the sleeve (13) is rectangular, but at the bottom of the sleeve (13), the sleeve (13) becomes a flat shape that tapers toward the other end.

[0026] The head (14) is provided with a plate-shaped base (15) and a tubular inlet (16) extending from the base (15). The head (14) is a component formed separately from the sleeve (13). The head (14) is made of synthetic resin.

[0027] The donor (15) has a shoulder portion (17) extending radially inward from one end portion (13a) of the sleeve (13), and a tubular upward extension portion (18) extending radially inward and upward from the center portion of the shoulder portion (17).

[0028] The head (14) is attached to one end (13a) of the sleeve (13) through the radially outer periphery (17a) of the shoulder portion (17).

[0029] The inlet section (16) is installed upward from the upper end of the upper extension section (18). The inlet section (16) is cylindrical and arranged coaxially with the axis (13b). The contents of the container body (11) are discharged from the inlet section (16). The cap closes the inlet section (16).

[0030] An outer circumference engaging portion (16a) is formed on the outer circumference of the inlet portion (16) to which the cap (not shown) engages. The outer circumference engaging portion (16a) is a male screw portion.

[0031] At the lower end of the entrance portion (16), a bottom plate portion (16b) extending radially inward from the inner surface of the entrance portion (16) and a hole (16c) penetrating the bottom plate portion (16b) in the axial direction (up and down direction) are formed.

[0032] A stopper part (18a) is formed on the outer circumference of the upper extension part (18) from the lower part of the inlet part (16) to restrict the rotational position of the cap, which is coupled to the outer circumference coupling part (16a), to a predetermined position.

[0033] Referring to FIGS. 1 and FIGS. 3, the head (14) has a peripheral portion (17a) of the shoulder portion (17) attached to one end portion (13a) of the sleeve (13).

[0034] The first end (13a) is a rectangular tubular portion that extends in a straight line along the axial direction of the sleeve (13). The first end (13a) is the upper end of the sleeve (13).

[0035] The shoulder portion (17) extends radially inward and upward from the first portion (13a).

[0036] The periphery portion (17a) of the shoulder portion (17) is provided with a flange portion (21) that is fixed to the axial cross-section (13c) of the end portion (13a) and an outer periphery portion (22) that is fixed to the inner circumference (13d) of the end portion (13a) below the flange portion (21).

[0037] Additionally, the head (14) is provided with a protrusion (23) that protrudes downward from the lower surface (17b) of the periphery (17a) of the shoulder portion (17). In FIG. 3, the lower surface (17b) is shown as a dashed line. The protrusion (23) is formed along the entire circumference of the inner surface (13d) of the end portion (13a) and is a rectangular annular shape when viewed axially from the sleeve (13).

[0038] The flange portion (21) is an annular portion that protrudes radially outward from the outer periphery portion (22) at the upper part of the periphery portion (17a). When viewed along the axial direction of the sleeve (13), the flange portion (21) has a square shape that follows the end portion (13a).

[0039] The lower surface of the flange portion (21) is fixed to the cross-section (13c) of the end portion (13a) by welding. The cross-section (13c) is the upper surface of the end portion (13a).

[0040] The side and top surfaces of the outer end of the flange portion (21) are chamfered into a curved shape by the chamfered portion (21a). The radius of curvature of the chamfered portion (21a) is equal to the plate thickness (t2) of the end portion (13a) or smaller than the plate thickness (t2) of the end portion (13a). Additionally, the corner portion of the flange portion (21) may be made into an edge without forming the chamfered portion (21a).

[0041] On the upper surface of the shoulder portion (17), the portion radially inward from the chamfered portion (21a) is a flat flat portion (17c).

[0042] The lower end of the outer surface of the flange portion (21) is in line with the outer surface of the end portion (13a).

[0043] The outer periphery (22) of the periphery portion (17a) extends in a straight line in the vertical direction along the inner surface (13d) of the end portion (13a). The outer periphery (22) is a stepped portion in which the periphery portion (17a) is recessed radially inward with respect to the flange portion (21), and extends from the lower surface of the flange portion (21) to the lower end of the periphery portion (17a). When viewed along the axial direction of the sleeve (13), the outer periphery (22) has a rectangular shape that follows the end portion (13a). The outer periphery (22) is fixed to the inner surface (13d) of the end portion (13a) by welding.

[0044] The outer surface (23a) of the protrusion (23) extends in a straight line in the vertical direction along the inner surface (13d) of the end portion (13a). The outer surface (23a) and the outer periphery (22) of the periphery portion (17a) have the same diameter, and the outer surface (23a) is continuous with the outer periphery (22). The outer surface (23a) of the protrusion (23) is fixed to the inner surface (13d) of the end portion (13a) by welding.

[0045] As illustrated in FIG. 3, when viewed in a cross-section perpendicular to the axial direction of the sleeve (13), the inner surface of the protrusion (23), which is the inner surface of the protrusion (23), extends in a straight line at an angle downward from the lower surface (17b) of the periphery (17a) and outward in the radial direction, and is connected to the lower end of the outer surface (23a). That is, the inner surface of the protrusion (23b) is an inclined surface that extends in a straight line so as to be located outward in the radial direction as it faces downward.

[0046] As a result, the radial thickness (t1) of the protrusion (23) decreases as it moves downward. In this embodiment, the inner surface of the protrusion (23b) is not in an upwardly convex curve shape (a curve shape in which the inner surface of the protrusion (23b) in FIG. 3 is concave toward the flange portion (21)), but is extended in a straight line at an angle, so the thickness (t1) can be significantly increased over the entire length direction (height direction) of the protrusion (23).

[0047] The thickness (t1) of the protrusion (23) is greater than the plate thickness (t2) of the end portion (13a).

[0048] In the vertical direction, the length (L1) of the protrusion (23) is longer than the length (L2) of the outer periphery (22) of the periphery (17a).

[0049] In addition, the length (L2) of the outer periphery (22) in the vertical direction is longer than the length (L3) of the flange portion (21).

[0050] In this way, the head (14) has a peripheral portion (17a) of the shoulder portion (17) attached to an end portion (13a) that extends straight in the axial direction of the sleeve (13), and the end portion (13a) is not bent toward the radial inner side of the sleeve (13). As a result, a large curved surface can be avoided at the connection portion (attachment portion) between the peripheral portion (17a) and the end portion (13a) of the head (14).

[0051] Additionally, the head (14) has a flange portion (21) fixed to the axial cross-section (13c) of the end portion (13a), and at the same time, the outer circumference (22) and the outer surface (23a) of the protrusion (23) are fixed to the inner surface (13d) of the end portion (13a). By doing so, the head (14) can be fixed to the end portion (13a) in the axial and radial directions, and the area of ​​the fixed portion can be secured significantly. Therefore, even if the end portion (13a) is straight, the head (14) can be firmly fixed to the sleeve (13).

[0052] FIG. 4 is a drawing illustrating an example of a method for manufacturing a container body (11). FIG. 4 shows the state of the molding process described later.

[0053] The container body (11) is manufactured by compression molding using a mandrel (30) and a mold (40).

[0054] FIG. 5a is a side view of the mandrel (30). FIG. 5b is a bottom view of the mandrel (30) seen from below.

[0055] Referring to FIGS. 4, 5a, and 5b, the mandrel (30) comprises a block-shaped mandrel body part (31) inserted into a sleeve (13) and a head molding part (32) formed on the lower surface of the mandrel body part (31).

[0056] A sleeve forming portion (31a) that fits into the inner circumference of the sleeve (13) is formed on the outer circumference of the lower part of the mandrel body (31). Additionally, on the outer circumference of the mandrel body (31), a detachment portion (31b) formed with a smaller diameter than the sleeve forming portion (31a) is formed above the sleeve forming portion (31a).

[0057] As illustrated in FIG. 5b, when viewed in the axial direction of the sleeve (13), the sleeve forming portion (31a) is a rectangular shape that follows the inner circumference of the sleeve (13). The four corner portions of the rectangular sleeve forming portion (31a) are forming corner portions (31c) for forming the four corner portions (25) of the sleeve (13). The forming corner portions (31c) are formed in a curved shape that follows the inner surface of the corner portions (25).

[0058] The head molding section (32) has a central molding section (32a) that follows the inner surface of the upper extension section (18) and the inner surface of the bottom plate section (16b), and a shoulder section molding section (32b) that follows the inner surface of the shoulder section (17).

[0059] On the outer periphery of the shoulder portion molding part (32b), a protrusion molding part (32c) is formed with a shape that follows the inner surface of the protrusion (23b).

[0060] The protruding molded portion (32c) is a chamfered portion in which the outer circumference of the lower portion of the mandrel body portion (31) is beveled in a straight line. The chamfered angle (θ) of this chamfered portion is, for example, 40° with respect to a straight line parallel to the axis (13b).

[0061] The protruding molded portion (32c) is formed along the entire circumference of the outer periphery of the shoulder molded portion (32b). By forming the protruding molded portion (32c), which is an inclined surface, the outer periphery of the shoulder molded portion (32b) becomes a tapered shape that gradually tapers downward.

[0062] The mold (40) comprises a first mold (41) having a base molding portion (41a) having a shape that follows the outer surface of the upper extension portion (18) and the outer surface of the shoulder portion (17), a second mold (42) having a shape that corresponds to the outer circumference of the inlet portion (16), a third mold (43) having a shape that corresponds to the tip of the inlet portion (16), and a fourth mold (44) having a shape that corresponds to the inner circumference of the inlet portion (16).

[0063] The first mold (41) is provided with a tubular outer guide portion (41b) that supports the outer circumference of one end portion (13a) of the sleeve (13). The outer guide portion (41b) extends straight in an axial direction along the one end portion (13a).

[0064] The method of manufacturing the container body (11) comprises an insertion process of inserting a mandrel (30) into a sleeve (13), a material fitting process of fitting the material of the head (14) punched by a punch after the insertion process into the sleeve (13), and a molding process of lowering the mandrel (30) within the sleeve (13) as shown in FIG. 4 to form a corner portion (25) by a molding corner portion (31c) and, at the same time, forming the head (14) by molding the material of the head (14) in a cavity formed between the mandrel (30) and the mold (40), and also fixing the periphery portion (17a) and the protrusion portion (23) to the end portion (13a).

[0065] In the above insertion process, the head molding part (32) is inserted through the opening of the upper part (other end) of the sleeve (13) not shown in FIG. 4, so that the mandrel (30) is inserted into the sleeve (13). At this time, the mandrel (30) can be inserted into the sleeve (13) by bringing the protruding molding part (32c), which is a straight chamfered part, into contact with the inner circumference of the opening of the upper part of the sleeve (13). As a result, when inserting the mandrel (30) into the sleeve (13), the mandrel (30) can be prevented from getting caught on the sleeve (13), and deformation of the sleeve (13) can be prevented, and at the same time, the mandrel (30) can be smoothly inserted into the sleeve (13).

[0066] In the above material fitting process, the material of the head (14) is heated and softened, then punched out by a punch and fitted into the sleeve (13).

[0067] In the above molding process, four corner portions (25) are formed by inserting the portion of the sleeve (13) on the end portion (13a) side between the molding corner portion (31c) and the first mold (41).

[0068] In this embodiment, the radius of curvature of the corner portion (25) is set to be relatively small, and the radius of curvature of the corner portion (25) is, for example, 1.5 mm or less.

[0069] If the radius of curvature of the corner portion (25) is small, the radius of curvature of the molding corner portion (31c) is also small, so that when the mandrel (30) is inserted into the sleeve (13), the molding corner portion (31c) is more likely to catch on the sleeve (13). In this embodiment, since the mandrel (30) is provided with a protruding molding portion (32c) which is a straight chamfered portion, the mandrel (30) can be prevented from catching on the sleeve (13) even if the radius of curvature of the molding corner portion (31c) is small.

[0070] In addition, in the above molding process, the head (14) is molded by compressing the material of the head (14), which has been softened by heating, between the mandrel (30) and the mold (40) as shown in Fig. 4, and at the same time, the head (14) is welded to the end portion (13a).

[0071] In the molding process, one end portion (13a) of the sleeve (13) is supported radially by the outer guide portion (41b) of the first mold (41). The flange portion (21) is formed by the material of the head (14) that fills the cavity between the cross-section (13c) of the one end portion (13a) and the base molding portion (41a). In the molding process, the inclined protrusion molding portion (32c) faces the cavity forming the flange portion (21), so the material of the head (14) can be well filled into the cavity forming the flange portion (21).

[0072] When the radius of curvature of the corner portion (25) is small, if a curved portion is formed in the sleeve (13) such that the end portion (13a) is curved radially inward, the deformation load of the sleeve (13) at this portion increases, making it easy for defects to occur in the shape of the sleeve (13) at the corner portion (25) of the end portion (13a). In this case, during the molding process, the material of the head (14) may be rolled inward toward the outside of the sleeve (13).

[0073] In this embodiment, since the end portion (13a) is straight and not curved inward in the radial direction, the corner portion (25) of the end portion (13a) can be formed into the correct shape. Therefore, the phenomenon of the material of the head (14) being rolled into the outside of the sleeve (13) can be avoided.

[0074] After the molding process, the container body (11) is removed from the mandrel (30) and the mold (40). The other end of the sleeve (13) is closed by means such as welding after the contents are filled into the container body (11).

[0075] In the container body (11), the head (14) is provided with a protrusion (23), and since the protrusion (23) is fixed to the end portion (13a), the area of ​​the fixed portion between the head (14) and the end portion (13a) can be increased.

[0076] In addition, as shown in FIG. 3, the thickness (t1) of the protrusion (23) is thicker than the plate thickness (t2) of the end portion (13a), so when the temperature of the head (14) decreases after molding, the temperature of the protrusion (23) is maintained to some extent. Therefore, the protrusion (23) can be welded well to the end portion (13a).

[0077] In addition, since the length (L1) of the protrusion (23) in the vertical direction is longer than the length (L2) of the outer periphery (22), the temperature of the protrusion (23) can be maintained well during welding.

[0078] As described above, according to the first embodiment to which the present invention is applied, the tube container (10) has a tubular sleeve (13), a plate-shaped base (15), and an inlet portion (16) that is inserted from the base (15), and has a head (14) that closes the opening of one end portion (13a) of the sleeve (13). The tube container (10) has a peripheral portion (17a) of the base (15) fixed to one end portion (13a), and the sleeve (13) is formed in a square shape having four corner portions (25) when viewed in the axial direction of the sleeve (13) from the side of the head (14). The first portion (13a) extends in a straight line along the axial direction of the sleeve (13), and the periphery portion (17a) is provided with a flange portion (21) that is attached to the cross-section (13c) along the axial direction of the first portion (13a), and an outer portion (22) that is attached to the inner surface (13d) of the first portion (13a). The head (14) is provided with an annular protrusion (23) that protrudes downward from the base (15), and the outer surface (23a) of the protrusion (23) is attached to the inner surface (13d) of the first portion (13a) below the outer portion (22), and the inner surface (23b) of the protrusion, which is the inner surface of the protrusion (23) on the inner side of the four corner portions (25), is an inclined surface that extends in a straight line so as to be located radially outward as it faces downward.

[0079] According to this configuration, the head (14) is fixed to the axial cross-section (13c) of the end portion (13a) of the sleeve (13) by the flange portion (21) of the periphery portion (17a) of the base (15), and is fixed to the inner surface portion (13d) of the end portion (13a) of the sleeve (13) by the outer periphery portion (22) of the periphery portion (17a) of the base (15) and the outer surface portion (23a) of the protrusion (23). By doing so, the periphery portion (17a) of the head (14) can be fixed to the end portion (13a) of the sleeve (13) in the axial and radial directions of the sleeve (13), thereby increasing the fixation strength between the sleeve (13) and the head (14). In addition, since the end portion (13a) of the sleeve (13) extends in a straight line along the axial direction of the sleeve (13) and is not bent in the radial direction, it is difficult for shape defects to occur in the sleeve (13) even if the radius of curvature of the four corner portions (25) in the end portion (13a) is reduced. That is, the material of the head (14) can be prevented from being rolled inward toward the outside of the sleeve (13), or wrinkles can be prevented in the sleeve (13) at the bending portion that is bent in the radial direction. Therefore, the radius of curvature of the four corner portions (25) of the sleeve (13) can be reduced. In addition, on the inner side of the four corner portions (25) of the sleeve (13), the shape of the mandrel (30) forming the inner surface of the protrusion (23b) becomes an inclined surface (protrusion forming portion (32c)) that extends in a straight line along the inclined surface of the inner surface of the protrusion (23b). Accordingly, when inserting the mandrel (30) into the sleeve (13), the mandrel (30) can be inserted into the sleeve (13) through the inclined surface of the mandrel (30), and the mandrel (30) can be prevented from getting caught on the corner portion (25) of the sleeve (13). Therefore, deformation of the sleeve (13) can be prevented during the molding of the sleeve (13).

[0080] Additionally, the inner surface (23b) of the protrusion is formed along the entire circumference of the inner surface of the protrusion (23).

[0081] According to this configuration, since the inner surface of the protrusion (23b) is formed along the entire circumference of the inner surface of the protrusion (23), the shape of the mandrel (30) forming the inner surface of the protrusion (23b) becomes an inclined surface (protrusion forming part (32c)) that is identical to the entire circumference of the inner surface of the protrusion (23b). Therefore, the mandrel (30) can be inserted into the sleeve (13) through the inclined surface formed along the entire circumference of the mandrel (30), thereby preventing the mandrel (30) from getting caught on the corner part (25) of the sleeve (13).

[0082] Additionally, the head (14) is fixed to the end portion (13a) by welding, and when viewed in a cross-section perpendicular to the axial direction of the sleeve (13), the thickness (t1) of the protrusion (23) is greater than the plate thickness (t2) of the end portion (13a), and the length (L1) of the protrusion (23) in the vertical direction is longer than the length (L2) of the outer portion (22).

[0083] According to this configuration, the temperature of the protrusion (23) can be maintained in a state suitable for welding, so that the head (14) can be welded well to the end portion (13a).

[0084] Additionally, the mandrel (30) used in the manufacture of the tube container (10) is provided with a molding corner portion (31c) for forming a corner portion (25), a head molding portion (32) having a shape that follows the head (14), and a protrusion molding portion (32c) formed on the outer periphery of the head molding portion (32) for forming a protrusion (23), and the protrusion molding portion (32c) is a straight chamfered portion that follows the inner surface of the protrusion (23b).

[0085] According to this configuration, when inserting the mandrel (30) into the sleeve (13), the mandrel (30) can be smoothly inserted into the sleeve (13) by using the protruding molded portion (32c), which is a straight chamfered portion, as a guide.

[0086] Additionally, the method for manufacturing a tube container (10) using a mandrel (30) comprises an insertion process in which the mandrel (30) is inserted into a sleeve (13) through a protruding molding part (32c), and a molding process in which the corner part (25) is formed by a molding corner part (31c) and the material of the head (14) is formed in a cavity formed between the mold (40) and the mandrel (30) to form the head (14), and the periphery part (17a) and the protruding part (23) are fixed to the end part (13a).

[0087] According to this configuration, by using a protrusion forming part (32c), which is a chamfered part for forming a protrusion (23) in the molding process, the mandrel (30) can be smoothly inserted into the sleeve (13) in the insertion process.

[0088] Although an embodiment of the present invention has been described above, the present invention is not limited to the specific embodiment described above, and various modifications and changes are possible within the scope of the intent of the invention as described in the claims, unless specifically limited in the description above. For example, the configurations of the above-described embodiment may be appropriately added or deleted, and the configurations of one embodiment may also be applied to other embodiments. Furthermore, the effects in the above-described embodiment are merely illustrative of the effects obtained from the present invention, and do not imply that the effects of the present invention are limited to the above effects.

[0089] In the above embodiment, the container body (11) is described as being manufactured by compression molding, but the present invention is not limited thereto, and the container body (11) may be manufactured by injection molding, for example, by injecting molten resin, which is the material of the head (14), into the cavity.

[0090] Additionally, in the above embodiment, the inner surface of the protrusion (23b) is described as being formed over the entire circumference of the inner surface of the protrusion (23), but the present invention is not limited thereto. For example, the inner surface of the protrusion (23b), which is a straight inclined surface, may be formed only on the inner side of the four corner portions (25), and other parts of the inner surface of the protrusion (23) may be formed as a curved inclined surface.

[0091] Additionally, the sleeve (13) may have a laminate structure in which a metal sheet, for example made of an aluminum-based material, is laminated to the main body of the sleeve (13), which is made of synthetic resin. In this case, the end portion (13a) of the sleeve (13) is extended in a straight line, and since the end portion (13a) having the laminate structure is not bent inward in the radial direction, the occurrence of wrinkles or bending at the end portion (13a) can be suppressed.

[0092] [Second Embodiment]

[0093] Hereinafter, a second embodiment applying the present invention will be described with reference to FIG. 6.

[0094] FIG. 6 is an enlarged cross-sectional view of the connection portion between the head (214) and the sleeve (213) in the second embodiment.

[0095] The tube container (210) comprises a container body (211) for holding contents and a cap (212) mounted on the container body (211).

[0096] The container body (211) is provided with a tube-shaped sleeve (213) and a head (214) attached to an axial end (213a) of the sleeve (213).

[0097] The sleeve (213) is a tube formed by cutting a tube body, which is continuously formed by extrusion molding or the like, into a predetermined length in the axial direction. The sleeve (213) is made of synthetic resin.

[0098] In the sleeve (213), one end (213a) and the other end (not shown) are open in the axial direction.

[0099] The opening of the end portion (213a) of the sleeve (213) is closed by the head (214) being fixed to the end portion (213a).

[0100] The opening of the other end of the sleeve (213) is closed by fixing the other end by a method such as welding, while the inner surfaces facing each other at the other end are in contact with each other.

[0101] When viewed in the axial direction, the sleeve (213) has a shape that follows the outer shape of the head (214). The outer shape of the head (214) may be circular or rectangular when viewed in the axial direction. The shape of the sleeve (213) is a flat shape that tapers toward the other end at the lower part of the sleeve (213).

[0102] In FIG. 6, the tube container (210) is shown in an upright position with the tube container (210) positioned so that the axis of the sleeve (213) (same as the axis (13b) in FIG. 3) is oriented in the up and down direction.

[0103] The head (214) has a plate-shaped base (215) and a tube-shaped inlet portion installed from the base (215). This inlet portion is not shown in FIG. 6 but is formed in the same way as the inlet portion (16) shown in FIG. 1 and FIG. 3.

[0104] The head (214) is a part formed separately from the sleeve (213). The head (214) is made of synthetic resin.

[0105] The donor (215) has a shoulder portion (217) extending radially inward from one end portion (213a) of the sleeve (213), and a tubular upward extension portion (218) extending radially inward and upward from the center portion of the shoulder portion (217).

[0106] The head (214) is fixed to one end (213a) of the sleeve (213) through the radially outer periphery (217a) of the shoulder portion (217).

[0107] The above-mentioned inlet portion is installed upward from the upper end of the upper extension portion (218). This inlet portion is a tubular shape arranged coaxially with the sleeve (213) and is positioned on the axis of the sleeve (213). Additionally, an outer circumference engaging portion (see outer circumference engaging portion (16a) in FIG. 3) to which the cap (212) engages is formed on the outer circumference of the inlet portion. The outer circumference engaging portion is a male screw portion.

[0108] At the lower end of the above-mentioned entrance portion, a bottom plate portion (identical to the bottom plate portion (16b) in FIG. 3) extending radially inward from the inner surface of the entrance portion, and a hole (identical to the hole (16c) in FIG. 3) penetrating the bottom plate portion in the axial direction (upward and downward direction) are formed.

[0109] The above-mentioned inlet is equipped with a check valve (not shown) to prevent backflow of contents and a nozzle (not shown). The contents of the container body (211) are discharged through the inlet and from the opening at the tip (top) of the nozzle.

[0110] The cap (212) comprises a tubular mounting portion mounted on the inlet portion, a disc-shaped upper wall portion (not shown) that closes the opening of the nozzle from above, and a tubular main wall portion (212c) that surrounds the mounting portion from the periphery.

[0111] The mounting portion of the cap (212) extends downward from the central portion of the upper wall. The main wall portion (212c) extends downward from the peripheral portion of the upper wall. These mounting portions and the main wall portion are arranged coaxially with the sleeve (213).

[0112] The cap (212) is attached to the inlet by the inner circumference engaging part, which is an inner thread formed on the inner circumference of the mounting part, engaging with the outer circumference engaging part (see outer circumference engaging part (16a) in FIG. 3).

[0113] The head (214) has a leading portion (217a) of the shoulder portion (217) attached to one end portion (213a) of the sleeve (213).

[0114] The end portion (213a) is a tubular portion that extends in a straight line along the axial direction of the sleeve (213). The end portion (213a) is the upper portion of the sleeve (213).

[0115] The shoulder portion (217) extends radially inward from the end portion (213a) and also slopes upward.

[0116] The periphery portion (217a) of the shoulder portion (217) is provided with a flange portion (221) that is fixed to the axial cross-section (213c) of the end portion (213a) and an outer periphery portion (222) that is fixed to the inner circumference (213d) of the end portion (213a) below the flange portion (221).

[0117] Additionally, the head (214) is provided with a protrusion (223) that protrudes downward from the lower surface (217b) of the peripheral portion (217a) of the shoulder portion (217). In FIG. 6, the lower surface (217b) is shown as a dashed line. The protrusion (223) is an annular shape arranged coaxially with the sleeve (213).

[0118] The flange portion (221) is an annular portion that protrudes radially outward with respect to the outer portion (222) at the upper part of the periphery portion (217a).

[0119] The flange portion (221) has its lower surface fixed to the cross-section (213c) of the end portion (213a) by welding. The cross-section (213c) is the upper surface of the end portion (213a).

[0120] The side and top surfaces of the outer end of the flange portion (221) are chamfered into a curved shape by the chamfered portion (221a). The radius of curvature of the chamfered portion (221a) is equal to the plate thickness (t2) of the end portion (213a) or is smaller than the plate thickness (t2) of the end portion (213a). Additionally, the corner portion of the flange portion (221) may be made into an edge without installing the chamfered portion (221a).

[0121] On the upper surface of the shoulder portion (217), the portion radially inward from the chamfered portion (221a) is a flat planar portion (217c).

[0122] The lower end of the outer surface of the flange portion (221) is in line with the outer surface of the end portion (213a).

[0123] The outer periphery (222) of the periphery portion (217a) extends in a straight line in the vertical direction along the inner surface (213d) of the end portion (213a). The outer periphery (222) is an end portion of the periphery portion (217a) formed concavely inwardly with respect to the flange portion (221), and extends from the lower surface of the flange portion (221) to the lower end of the periphery portion (217a). The outer periphery (222) is fixed to the inner surface (213d) of the end portion (213a) by welding.

[0124] The outer surface (223a) of the protrusion (223) extends in a straight line in the vertical direction along the inner surface (213d) of the end portion (213a). The outer surface (223a) and the outer circumference (222) of the periphery portion (217a) have the same diameter, and the outer surface (223a) is continuous with the outer circumference (222). The outer surface (223a) of the protrusion (223) is fixed to the inner surface (213d) of the end portion (213a) by welding.

[0125] As shown in FIG. 6, in a cross-section perpendicular to the axial direction of the sleeve (213), the inner surface of the protrusion (223b), which is the inner surface of the protrusion (223), extends in a straight line at an angle downward from the lower surface (217b) of the peripheral portion (217a) and also outward in the radial direction, and is connected to the lower end of the outer surface (223a). As a result, the radial thickness (t1) of the protrusion (223) decreases as it goes downward. In this second embodiment, since the inner surface of the protrusion (223b) is not in a curved shape that is convex upward, but extends in a straight line at an angle, the thickness (t1) of the protrusion (223) can be significantly increased over the entire length direction (height direction) of the protrusion (223).

[0126] Also, the thickness (t1) of the protrusion (223) is greater than the plate thickness (t2) of the end portion (213a).

[0127] In this way, the head (214) has a peripheral portion (217a) of the shoulder portion (217) attached to an end portion (213a) that extends straight in the axial direction of the sleeve (213), and the end portion (213a) is not bent toward the radial inner side of the sleeve (213). As a result, a large curved surface can be avoided at the connection portion (attachment portion) between the peripheral portion (217a) of the head (214) and the end portion (213a).

[0128] The outer diameter of the main wall portion (212c) of the cap (212) is almost the same as the outer diameter of the sleeve (213), and the outer surface of the main wall portion (212c) and the outer surface of the sleeve (213) are continuous, so that the tube container (210) has a neat appearance.

[0129] In detail, the radially outer portion of the main wall portion (212c) of the cap (212) is an overlapping portion (212e) that overlaps with the position of the end portion (213a) of the sleeve (213) in the radial direction. Additionally, the overlapping portion (212e) is a portion that is outer from the virtual line shown within the main wall portion (212c) in FIG. 6.

[0130] The lower portion (212f) of the main wall portion (212c) faces from above the flat portion (217c) installed on the upper surface of the shoulder portion (217) of the base (215) on the outside of the entrance portion.

[0131] In this way, when the main wall portion (212c) of the cap (212) is provided with an overlapping portion (212e), the lower portion (212f) of the main wall portion (212c) faces the flat portion (217c) of the shoulder portion (217), so the upper and lower gap (G) between the lower portion (212f) and the shoulder portion (217) can be reduced. By doing so, the sense of unity between the main wall portion (212c) of the cap (212) and the sleeve (213) can be increased, and the appearance of the tube container (210) is good.

[0132] The container body (211) is manufactured by compression molding using a mold corresponding to the shape of the outer surface of the shoulder portion (217) and the shape of the inlet portion of the head (214), as in FIG. 4, with a mandrel inserted into the sleeve (213).

[0133] According to the second embodiment, a cap (212) is installed having a mounting portion mounted on the inlet portion of the head (214) and a cylindrical main wall portion (212c) surrounding the mounting portion from the periphery, wherein the main wall portion (212c) is installed to overlap with the position of the end portion (213a) in the radial direction, and the lower portion (212f) of the main wall portion (212c) faces from above a flat portion (217c) installed on the upper surface of the base (215) on the outside of the inlet portion.

[0134] According to this configuration, when the main wall portion (212c) of the cap (212) is installed to overlap with the position of the end portion (213a) in the radial direction, the lower portion (212f) of the main wall portion (212c) faces the flat portion (217c) of the upper surface of the base (215), so the gap (G) between the lower portion (212f) of the main wall portion (212c) and the upper surface of the base (215) can be reduced. As a result, the appearance of the tube container (210) can be improved, and at the same time, foreign matter can be prevented from entering the cap (212) through the gap (G) between the lower portion (212f) of the main wall portion (212c) and the upper surface of the base (215). Explanation of the symbols

[0135] 10, 210: Tube container 13, 213: Sleeve 13a, 213a: First part 13c, 213c: Cross-section 13d, 213d: If you give it to me 14, 214: Head 15,215: Donate 16: Entrance 17a, 217a: Main part 21, 221: Flange section 22, 222: Outsourcing 23, 223: Protrusion 23a, 223a: Outer surface 23b, 223b: Inner surface of the protrusion 25: Corner section 30: Mandrel 31c: Corner section for forming 32: Head molding section 40: Mold t1: Thickness (thickness of the protrusion) t2: Plate thickness (plate thickness of one end) L1: Length (length of the protrusion) L2: Length (length of the outer perimeter)

Claims

Claim 1 A tube container comprising a tube-shaped sleeve, a plate-shaped base, and an inlet portion extending from the base, and a head that closes the opening of one end portion of the sleeve, wherein the peripheral portion of the base is fixed to the one end portion, and the sleeve is formed in a square shape having four corner portions when viewed from the head side in the axial direction of the sleeve, wherein the one end portion extends straight in the axial direction of the sleeve, and the peripheral portion has a flange portion fixed to the axial cross-section of the one end portion and an outer portion fixed to the inner circumference of the one end portion, and the head has an annular protrusion protruding downward from the base, and the outer circumference of the protrusion is fixed to the inner circumference of the one end portion below the outer circumference, and on the inner side of the four corner portions, the inner circumference of the protrusion is an inclined surface that extends straight outward so as to be located radially outward as it goes downward. Claim 2 In claim 1, the inner surface of the protrusion is a tube container formed around the entire circumference of the inner surface of the protrusion. Claim 3 A tube container according to claim 1, wherein the head is fixed to the end portion by welding, and in a cross-section perpendicular to the axial direction of the sleeve, the thickness of the protrusion is greater than the plate thickness of the end portion, and in the vertical direction, the length of the protrusion is longer than the length of the outer periphery. Claim 4 A mandrel used in the manufacture of a tube container described in claim 1, comprising a molding corner portion for forming the corner portion, a head molding portion having a shape that follows the head, and a protrusion molding portion formed on the outer periphery of the head molding portion for forming the protrusion, wherein the protrusion molding portion is a straight chamfered portion that follows the inner surface of the protrusion. Claim 5 A method for manufacturing a tube container using a mandrel as described in paragraph 4, comprising: an insertion process of inserting the mandrel into the sleeve through the protrusion forming part; a molding process of forming the head by forming the head in a cavity formed between the mold and the mandrel while forming the corner part by the molding corner part, and also fixing the periphery part and the protrusion part to the end part.

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