Cap and method for manufacturing the same

Abstract

A cap capable of preventing an engaging protrusion of an outer cylinder of a cap body from being damaged during a demolding process when the cap is injection molded. [Solution] A cap body (11) that can be attached to a container has an outer tube (20) that can fit onto the outer periphery of the mouth of the container, and an engaging protrusion (47) that protrudes inward in the radial direction (16) is formed on the inner periphery of the outer tube (20), and the outer tube (20) is formed with a finger-hook recess (49) that is recessed inward in the radial direction (16) from the outer surface (20a) of the outer tube (20), and a first lightening groove (51) that is open at the bottom, and the first lightening groove (51) is located outside the engaging protrusion (47) in the radial direction (16) and is formed in a range in the circumferential direction that corresponds to the finger-hook recess (49), and when released from the mold, the engaging protrusion (47) is pushed outward in the radial direction (16), and a portion (87) between the inner periphery of the outer tube (20) and the first lightening groove (51) is retracted outward in the radial direction (16) from the mold.

Description

[Technical Field]

[0001] The present invention relates to a hinged cap and a method for manufacturing the same. [Background technology]

[0002] Conventionally, this type of cap has, for example, a cap body 111 that can be attached to the mouth of a container, and a lid 113 that is connected to the cap body 111 via a hinge 112, as shown in FIG.

[0003] The cap body 111 has an outer cylinder 114 and an inner cylinder 115, and an attachment groove 116 is formed between the outer cylinder 114 and the inner cylinder 115. The cap body 111 is attached to a container by inserting the opening of the container into the attachment groove 116.

[0004] An engaging protrusion 118 that protrudes inward in the radial direction 117 is formed around the entire inner periphery of the outer tube 114. An engaging recess is formed around the entire outer periphery of the mouth of the container. When the mouth of the container is inserted into the mounting groove 116 of the cap body 111, the engaging protrusion 118 engages with the engaging recess. The outer cylinder 114 has a gap 119 that is open downward and formed over almost the entire circumference.

[0005] A finger-hanging recess 120 is formed on the outer periphery of outer tube 114, recessed inward in radial direction 117 from outer peripheral surface 114a of outer tube 114. In addition, lid 113 is provided with a flange 121. Finger-hanging recess 120 and flange 121 are located on the opposite side of hinge 112 with respect to axis 122 of cap 110 in the closed state. The above-described cap 110 is described in, for example, Patent Document 1 below.

[0006] Cap 110 is manufactured by injection molding. In this process, in a demolding step in which the synthetic resin material solidified in the mold is released from the mold, first core 127 forming mounting groove 116 (see FIG. 14) is demolded downward 128 as shown by imaginary line (A) in FIG. 15, and then second core 129 forming finger hook recess 120 is demolded in lateral direction 130 as shown by imaginary line (B) in FIG. 15. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4461317 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the conventional type described above, when first core 127 is demolded downward 128 during the demolding process in injection molding cap 110, finger hook recess 120 is pressed from the side by second core 129, making it difficult for outer cylinder 114 to deform and retreat toward outer side 131 in radial direction 117. As a result, first core 127 gets caught on engaging protrusion 118 of outer cylinder 114, preventing smooth demolding downward 128, and there is a risk that engaging protrusion 118 will be damaged by first core 127.

[0009] An object of the present invention is to provide a cap and a method for manufacturing the cap that can prevent damage to an engaging protrusion on the outer tube of the cap body during the demolding process when the cap is injection molded. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides a cap having a cap body that can be attached to the mouth of a container, a pouring outlet provided in the cap body, and a lid that opens and closes the pouring outlet, The lid is connected to the cap body via a hinge so as to be rotatable in the opening and closing directions, The cap body has an outer cylinder that can be fitted onto the outer periphery of the mouth of the container, An engaging protrusion that protrudes radially inward is formed on the inner periphery of the outer cylinder, the engaging protrusion is capable of engaging with the opening of the container in the axial direction of the cap; A finger-hook recess is formed on the outer periphery of the outer cylinder, recessed radially inward from the outer periphery of the outer cylinder, The finger recess is disposed on the opposite side of the hinge with respect to the axis of the cap, and faces the lower end of the outer periphery of the closed lid; A first lightening groove having an open bottom is formed in the outer cylinder, The first lightening groove is located radially outward of the engaging protrusion and is formed in a range corresponding to the finger hook recess in the circumferential direction, The present invention is characterized in that, when the mold is released, the engaging protrusion is pushed radially outward, causing the area between the inner circumference of the outer tube and the first lightening groove to retreat radially outward from the mold.

[0011] According to this, by forming the first lightening groove in the outer tube, the area between the inner circumference of the outer tube and the first lightening groove can easily deform radially outward and escape.

[0012] Therefore, in the demolding process when manufacturing a cap by injection molding, the first core that forms the first lightening groove is demolded to form the first lightening groove, and then when the second core that forms the inner circumference of the outer tube is demolded, the engaging protrusion of the outer tube is pushed radially outward, but because the first lightening groove is formed in the outer tube, the area between the inner circumference of the outer tube and the first lightening groove can easily deform radially outward and retract from the second core. This makes it possible to prevent the engaging protrusion of the outer cylinder of the cap body from being damaged when the cap body is released from the mold.

[0013] After the cap is manufactured, the fingertip can be easily hooked onto the lid by pressing it against the finger-hook recess of the closed cap. In this state, the lid can be easily opened by pushing the fingertip in the opening direction.

[0014] According to the cap of the present invention, the cap body has an inner cylinder that can be fitted onto the inner periphery of the mouth of the container, A mounting groove is formed between the inner and outer cylinders, The cap body can be attached to the container by inserting the opening of the container into the attachment groove; The depth from the bottom end of the outer cylinder to the innermost end of the first recessed groove is shallower than the depth from the bottom end of the outer cylinder to the innermost end of the mounting groove, The finger-hanging recess is preferably located radially outward of the attachment groove and above the innermost end of the first lightening groove. This allows the depth of the finger-hanging recess in the radial direction to be large.

[0015] According to the cap of the present invention, the width of the first lightening groove in the radial direction is preferably greater than the height from the inner periphery of the outer cylinder to the inner tip end of the engaging protrusion in the radial direction.

[0016] According to this, in the demolding process, the first core that forms the first lightening groove is demolded to form the first lightening groove, and then when the second core that forms the inner circumference of the outer tube is demolded, the area between the inner circumference of the outer tube and the first lightening groove deforms radially outward.

[0017] At this time, because the width of the first lightening groove is greater than the height of the engaging protrusion, a sufficient amount of deformation can be ensured in the area between the inner periphery of the outer cylinder and the first lightening groove, thereby allowing the area between the inner periphery of the outer cylinder and the first lightening groove to reliably retreat from the second core.

[0018] According to the cap of the present invention, a second lightening groove that is open at the bottom is formed in the outer cylinder, the first recess is disposed on the opposite side of the hinge with respect to the axis of the cap, The second lightening groove is preferably disposed on the side closer to the hinge with respect to the axis of the cap.

[0019] According to this, by forming the second lightening groove in the outer tube, the area between the inner circumference of the outer tube and the second lightening groove can easily deform radially outward and escape.

[0020] Therefore, in the demolding process when manufacturing a cap by injection molding, the fourth core that forms the second lightening groove is demolded to form the second lightening groove, and then when the second core that forms the inner circumference of the outer tube is demolded, the engaging protrusion of the outer tube is pushed radially outward, but because the second lightening groove is formed in the outer tube, the area between the inner circumference of the outer tube and the second lightening groove can easily deform radially outward and retract from the second core. This makes it possible to prevent the engaging protrusion of the outer cylinder of the cap body from being damaged during the demolding process.

[0021] According to the cap of the present invention, the cap body has a top wall that covers the mouth of the container, The outer cylinder has a fixed portion provided on the outer peripheral edge of the top wall and a detachable portion connected to the fixed portion via a breakable weakened portion, Preferably, the separation part is provided with a hinge.

[0022] When the lid is pulled in the open position, the tensile force is transmitted to the weakened portion via the hinge, causing the weakened portion to break and the detachable portion to detach from the fixed portion. This allows the cap body to be easily removed from the mouth of the container, making it easy to dispose of the cap.

[0023] The present invention provides a manufacturing method for manufacturing the above-mentioned cap by injection molding, comprising the steps of: In a demolding process, the synthetic resin material solidified in the mold is released from the mold. The first core having the first recessed groove formed therein is released from the mold; Next, the second core forming the inner periphery of the outer cylinder is released from the mold. Thereafter, the third core forming the finger-hanging recess is released from the mold.

[0024] According to this method, the first core is demolded to form the first lightening groove, and then the second core is demolded to form the inner periphery of the outer cylinder. During this process, the area between the inner periphery of the outer cylinder and the first lightening groove can easily deform radially outward and escape from the second core. This makes it possible to prevent the engaging protrusion of the outer cylinder of the cap body from being damaged when the cap body is released from the mold. Thereafter, the third core is released from the mold to form a finger-hanging recess. [Effects of the Invention]

[0025] As described above, according to the present invention, it is possible to prevent the engaging protrusion of the outer cylinder of the cap body from being damaged during the mold release step when the cap is injection molded. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a cross-sectional view of a cap according to a first embodiment of the present invention, showing the capped state. [Figure 2] FIG. 2 is a cross-sectional view of the cap, showing the cap in an opened state. [Figure 3] FIG. 3 is a view taken along the arrow XX in FIG. 2. [Figure 4] FIG. 3 is a view taken along the arrow YY in FIG. 2. [Figure 5] FIG. 4 is an enlarged cross-sectional view of a finger-hook recess of the cap. [Figure 6] FIG. 2 is an enlarged cross-sectional view of the dispensing tube of the cap. [Figure 7] FIG. 2 is an enlarged cross-sectional view of the hinge of the cap. [Figure 8] FIG. 2 is a view taken along the arrow XX in FIG. [Figure 9] 3 is a cross-sectional view of a mold used for injection molding of the cap, showing the mold in a closed state. FIG. [Figure 10] 10 is a cross-sectional view of a mold for explaining the manufacturing method of the cap, showing the procedure for opening the mold. [Figure 11] 10 is a cross-sectional view of a mold for explaining the manufacturing method of the cap, showing the procedure for opening the mold. [Figure 12] 10 is a cross-sectional view of a mold for explaining the manufacturing method of the cap, showing the state in the middle of releasing the second core from the mold. FIG. [Figure 13] 10 is a cross-sectional view of a mold for explaining the manufacturing method of the cap, showing the procedure for opening the mold. [Figure 14] FIG. 1 is a cross-sectional view of a conventional cap. [Figure 15] 10 is a cross-sectional view of a mold for explaining the manufacturing method of the cap, showing the procedure for opening the mold. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, embodiments of the present invention will be described with reference to the drawings. (First embodiment)

[0028] As shown in Figures 1 and 2, reference numeral 1 denotes a cap made of synthetic resin having a cap body 11 that can be attached to the mouth 3 of a container 2 such as a PET bottle, a spout 12 provided on the cap body 11, and a lid 13 that opens and closes the spout 12. Although the cap body 11 is directly attached to the mouth 3 of the container 2, it may be indirectly attached to the mouth 3 via an inner plug or the like.

[0029] As shown in Figure 1, the direction of the axis 14 passing through the center of the closed cap 1 is defined as the up-down direction 15, the direction perpendicular to the axis 14 is defined as the radial direction 16, and as shown in Figures 3 and 4, the circumferential direction centered on the axis 14 is defined as the circumferential direction 17. As shown in FIG. 1, a protrusion 5 that protrudes outward in a radial direction 16 is formed around the entire outer periphery of the tip of the mouth 3 of the container 2 .

[0030] As shown in Figures 1 to 5, the cap body 11 has a disk-shaped top wall 19 that covers the mouth portion 3, a cylindrical outer tube 20 that extends downward from the outer peripheral edge of the top wall 19, and a cylindrical inner tube 21 that extends downward from the top wall 19 inside the outer tube 20. An engaging protrusion 47 that protrudes inward in the radial direction 16 is formed around the entire inner periphery of the lower end of the outer cylinder 20 .

[0031] Between the outer tube 20 and the inner tube 21, an attachment groove 22 is formed around the entire circumference, closed at the top by a top wall 19 and open at the bottom. When the mouth portion 3 of the container 2 is fitted into the attachment groove 22 from below, the outer tube 20 fits onto the outer periphery of the mouth portion 3 and the inner tube 21 fits onto the inner periphery of the mouth portion 3, thereby attaching the cap body 11 to the container 2. At this time, the engagement protrusion 47 of the outer tube 20 engages with the protrusion 5 of the mouth portion 3 in the vertical direction 15 (an example of the axial direction of the cap 1).

[0032] An upwardly protruding cylindrical pouring tube 24 is provided on the upper surface of the top wall 19, and an upwardly protruding annular locking member 31 is formed thereon. The pouring tube 24 is disposed inside the locking member 31 in the radial direction 16. The pouring outlet 12 is formed at the tip of the pouring tube 24. An introduction portion 25 for introducing the liquid content (not shown) contained in the container 2 from the opening portion 3 into the pouring tube 24 is provided on the lower surface of the top wall 19.

[0033] As shown in Figures 2, 4, and 6, the introduction portion 25 has a cylindrical peripheral wall 26 that protrudes downward (i.e., toward the container 2) from the underside of the top wall 19 and enters the mouth portion 3, a circular bottom wall 27 that closes the bottom of the peripheral wall 26, an introduction space 28 formed within the peripheral wall 26, an opening 29 formed in a part of the peripheral wall 26, and a flat valve body 30 that opens and closes the opening 29. The introduction space 28 and the inside of the lower end of the dispensing tube 24 are in communication with each other, and the introduction space 28 and the inside of the dispensing tube 24 are continuous with each other.

[0034] 6, the valve element 30 is flexible and flexes flexibly inward of the peripheral wall 26 as shown by the imaginary lines to open the opening 29, and returns to its original shape as shown by the solid lines to close the opening 29. The lower end of the valve element 30 is integrally connected to the bottom wall 27, and the upper end of the valve element 30 can swing in opening and closing directions 33 and 34.

[0035] 1 to 4, the lid 13 is connected to the cap body 11 via a hinge 37 and is rotatable about the hinge 37 in opening and closing directions 38 and 39. The lid 13 has a circular lid plate 42, a cylindrical skirt 43 provided on the outer periphery of the lid plate 42, and a cylindrical seal member 44 provided inside the skirt 43.

[0036] 1, when the cap 1 is closed, the sealing member 44 is inserted into the dispensing tube 24 and comes into tight contact with the entire inner circumferential surface of the dispensing tube 24. This seals the gap between the dispensing tube 24 and the lid 13. In addition, when the cap 1 is closed, the end of the opening side of the skirt 43 is fitted onto the locking member 31 of the cap body 11, thereby preventing the closed lid 13 from opening accidentally due to vibration, etc.

[0037] The skirt 43 is formed with a flange 45 that protrudes outward in the radial direction 16. As shown in FIG. 1, when the lid 13 is closed, the flange 45 is located at the lower end of the skirt 43 on the opposite side of the hinge 37 with respect to the axis 14 of the cap 1.

[0038] 2 and 5, a finger-hanging recess 49 is formed on the outer periphery of the outer tube 20, recessed inward in the radial direction 16 from the outer peripheral surface 20a of the outer tube 20. As shown in FIG. 1, the finger-hanging recess 49 is located on the opposite side of the hinge 37 with respect to the axis 14 of the cap 1, and faces the underside of the flange 45 of the closed lid 13. As shown in FIG. 3, the finger-hanging recess 49 is formed in the range of a predetermined angle α (for example, 60°) in the circumferential direction 17 around the axis 14 of the cap 1.

[0039] 1 and 2, first and second lightening grooves 51, 52, each open at the bottom, are formed in the outer cylinder 20. The first lightening groove 51 is located on the opposite side of the axis 14 of the cap 1 from the hinge 37. The second lightening groove 52 is located on the side closer to the hinge 37 from the axis 14.

[0040] The first and second lightening grooves 51, 52 are each located outside the engaging protrusion 47 in the radial direction 16. The first lightening groove 51 is formed in a range corresponding to the finger hook recess 49 in the circumferential direction 17, that is, in a range of a predetermined angle β (for example, 70°) in the circumferential direction 17 around the axis 14 as shown in FIG.

[0041] 5, a depth D1 from the lower end of the outer tube 20 to the innermost end of the first lightening groove 51 is set to be shallower than a depth D2 from the lower end of the outer tube 20 to the innermost end of the mounting groove 22. Furthermore, a width W1 of the first lightening groove 51 in the radial direction 16 is set to be greater than a height H from the inner periphery of the outer tube 20 to the inner tip end of the engaging protrusion 47 in the radial direction 16. Furthermore, the finger hook recess 49 is located outside the attachment groove 22 in the radial direction 16 and above the innermost end of the first lightening groove 51 .

[0042] 2, 5, 7, and 8, the outer cylinder 20 has a fixed portion 55 provided on the outer peripheral edge of the top wall 19, and a detachable portion 57 connected to the fixed portion 55 via a breakable first weakened portion 56. The first weakened portion 56 is formed over almost the entire circumference of the outer cylinder 20. The first and second lightening grooves 51, 52 are formed in the detachable portion 57 of the outer cylinder 20. One end of the hinge 37 is connected to the separation portion 57 of the outer cylinder 20 , and the other end is connected to the skirt 43 of the lid 13 .

[0043] 3, 4, and 8, a breakable second weakened portion 59 is formed in the detachment portion 57 of the outer tube 20. The second weakened portion 59 runs vertically through the detachment portion 57 in the up-down direction 15 (the direction of the axis 14), is disposed beside the hinge 37 in the circumferential direction 17, and is connected to the first weakened portion 56 at one point. The cap 1 is manufactured by injection molding. Next, a method for manufacturing the cap 1 will be described.

[0044] As shown in Fig. 9, reference numeral 71 denotes a mold used when injection-molding cap 1 in the open state shown in Fig. 2. Mold 71 has a lower mold 72 that forms the lower side of cap body 11 and the outer side of lid 13, and an upper mold 73 that forms the upper side of cap body 11 and the inner side of lid 13.

[0045] The lower mold 72 has a first core 75 that is arc-shaped in a plan view and forms the first lightening groove 51, a second core 76 that is cylindrical in a plan view and forms the mounting groove 22, a third core 77 that forms the finger hook recess 49, a fourth core 78 that is arc-shaped in a plan view and forms the second lightening groove 52, a fifth core 79 that forms the underside of the top wall 19, the inside of the inner cylinder 21, the introduction portion 25, etc., and a sixth core 80 that forms the outside of the lid 13, etc. These first to sixth cores 75 to 80 are each movable in the vertical direction 15.

[0046] The upper mold 73 has a seventh core 81 that forms the inner surface of the pouring tube 24, an eighth core 82 that forms the outer surface of the pouring tube 24 and the upper surface of the top wall 19, a ninth core 83 that forms the inner surface of the lid 13, a tenth core 93 that forms the outer surface of the locking member 31, and an eleventh core 94 adjacent to a part of the tenth core 93. These seventh to eleventh cores 81 to 83, 93, and 94 are each movable in the vertical direction 15.

[0047] The manufacturing method of the cap 1 includes a filling step of filling a molded product space 84 (see Figure 9) inside the mold 71 with molten synthetic resin material 85 (see Figure 10), a cooling step of cooling and solidifying the filled synthetic resin material 85, and a demolding step of releasing the synthetic resin material 85 that has been cooled and solidified inside the mold 71 from the mold 71.

[0048] According to this method, first, the filling process is performed, then the cooling process is performed, and then the demolding process is performed. In the demolding process, first, as shown in Fig. 10, the first core 75, the fourth core 78, the fifth core 79, and the sixth core 80 are each moved downward 8 and demolded. This forms the first and second lightening grooves 51 and 52, the lower surface of the top wall 19, the inside of the inner cylinder 21, the introduction portion 25, the outside of the lid 13, etc.

[0049] Next, as shown in Fig. 11 , the second core 76 is moved downward 8 and released from the mold, thereby forming the mounting groove 22. At this time, as shown in Fig. 12 , the engaging protrusion 47 of the outer tube 20 is pressed toward the outer side A in the radial direction 16, but because the first lightening groove 51 is formed in the outer tube 20, the region 87 between the inner periphery of the outer tube 20 and the first lightening groove 51 easily deforms toward the outer side A in the radial direction 16 and can be retracted from the second core 76 moving downward 8.

[0050] At this time, as shown in Fig. 5, the width W1 of the first lightening groove 51 is larger than the height H of the engaging protrusion 47, so that a sufficient amount of deformation can be ensured for the portion 87. This allows the portion 87 to reliably escape from the second core 76, as shown in Fig. 12.

[0051] Similarly, since the second lightening groove 52 is formed in the outer tube 20, the area 88 between the inner circumference of the outer tube 20 and the second lightening groove 52 can easily deform toward the outside A in the radial direction 16 and move away from the second core 76 moving downward 8. This makes it possible to prevent the engaging protrusion 47 of the outer cylinder 20 from being damaged when the mold is released.

[0052] Thereafter, the seventh core 81, the eighth core 82, the ninth core 83, and the tenth core 93 are sequentially moved upward 9 (see Figure 11) and released from the mold, thereby forming the dispensing tube 24, the upper surface of the top wall 19, the inside of the lid 13, the locking member 31, etc., as shown by the solid lines in Figure 13. 13, the third core 77 and the eleventh core 94 are simultaneously moved upward 9 and released from the mold, thereby forming the finger-hanging recess 49. This completes the production of the cap 1 as shown in FIG.

[0053] After producing the cap 1 as described above, the cap 1 is attached to the container 2 with the lid 13 closed (closed state) as shown by the solid line in Fig. 1. As a result, the opening 3 of the container 2 is fitted into the attachment groove 22 from below as shown by the imaginary line in Fig. 1, and the cap 1 is attached to the container 2.

[0054] At this time, the engaging protrusion 47 of the outer cylinder 20 engages with the protrusion 5 of the mouth 3 in the vertical direction 15, so that the cap body 11 can be prevented from accidentally coming off the mouth 3 of the container 2.

[0055] As shown by the imaginary lines in Figure 1, by pressing fingertip 91 against finger-hook recess 49 of closed cap 1, fingertip 91 can be easily hooked onto flange 45 of lid 13. In this state, by pressing flange 45 in opening direction 38 with fingertip 91, lid 13 can be easily opened.

[0056] As shown in Figure 5, the depth D1 of the first lightening groove 51 is set shallower than the depth D2 of the mounting groove 22, and the finger hook recess 49 is located outside the mounting groove 22 in the radial direction 16 and above the inner end of the first lightening groove 51, so that the depth D3 of the finger hook recess 49 in the radial direction 16 can be secured large.

[0057] 4, the first lightening groove 51 is formed in the outer tube 20, so that when the cap 1 is attached to the container 2 as described above, the outer tubes 20 are pulled in opposite directions B, as shown in FIG. 3, and as a result, the finger hook recesses 49 are pressed against the inner side C in the radial direction 16. This allows the fingertips 91 to be reliably pressed against the finger hook recesses 49 and easily hooked onto the flange 45 of the lid 13.

[0058] When disposing of the cap 1 and the container 2, by pulling the lid 13 in the open state, the second weakened portion 59 breaks first, and then the first weakened portion 56 breaks, and the detachable portion 57 of the outer tube 20 detaches from the fixed portion 55. This allows the cap body 11 to be easily removed from the mouth portion 3 of the container 2, and the cap 1 and the container 2 can be easily disposed of separately.

[0059] In the above embodiment, the engaging protrusion 47 is formed around the entire inner periphery of the lower end of the outer cylinder 20, but it may not be around the entire periphery and may be partially missing.

[0060] In the above embodiment, as shown in Figure 10, the first core 75, the fourth core 78, the fifth core 79, and the sixth core 80 are each released from the mold, then the second core 76 is released from the mold as shown in Figure 11, and then the seventh to tenth cores 81, 82, 83, and 93 are each released from the mold, and then the third core 77 and the eleventh core 94 are released from the mold as shown by the imaginary lines in Figure 13. However, it is sufficient to release the first core 75, the second core 76, and the third core 77 sequentially in this order, and the order in which cores other than the first to third cores 75 to 77 are released from the mold may be arbitrary. [Explanation of symbols]

[0061] 1 cap 2 containers 3 Mouth 11 Cap body 12 spout 13 Lid 14 axis 16 Radial 17 Circumferential direction 19 Top Wall 20 outer cylinder 20a Outer surface of outer cylinder 21 Inner cylinder 22 Mounting groove 37 Hinge 38 Opening direction 39 Close direction 47 Engagement protrusion 49 Finger recess 51 First recess 52 Second recess 55 Fixed part 56 First weakened section 57 Detachment section 71 Mold 75~77 1st~3rd Core 87 The area between the inner circumference of the outer cylinder and the first recessed groove A Outer side in the radial direction D1: Depth from the bottom end of the outer cylinder to the inner end of the first recess D2 Depth from the bottom end of the outer cylinder to the inner end of the mounting groove H Height of engaging protrusion W1 Width of first recess

Claims

1. A cap having a cap body that can be attached to the mouth of a container, a pouring outlet provided in the cap body, and a lid that opens and closes the pouring outlet, The lid is connected to the cap body via a hinge so as to be rotatable in the opening and closing directions, The cap body has an outer cylinder that can be fitted onto the outer periphery of the mouth of the container, An engaging protrusion that protrudes radially inward is formed on the inner periphery of the outer cylinder, the engaging protrusion is capable of engaging with the opening of the container in the axial direction of the cap; A finger-hook recess is formed on the outer periphery of the outer cylinder, recessed radially inward from the outer periphery of the outer cylinder, The finger recess is disposed on the opposite side of the hinge with respect to the axis of the cap, and faces the lower end of the outer periphery of the closed lid; A first lightening groove having an open bottom is formed in the outer cylinder, the first lightening groove is located radially outward of the engaging protrusion and is formed in a range corresponding to the finger hook recess in the circumferential direction; A cap characterized in that, when released from the mold, the engaging protrusion is pushed radially outward, causing the area between the inner circumference of the outer tube and the first lightening groove to retreat radially outward from the mold.

2. The cap body has an inner cylinder that can be fitted onto the inner periphery of the mouth of the container, A mounting groove is formed between the inner and outer cylinders, The cap body can be attached to the container by inserting the opening of the container into the attachment groove; the depth from the lower end of the outer cylinder to the innermost end of the first recessed groove is shallower than the depth from the lower end of the outer cylinder to the innermost end of the mounting groove; 2. The cap according to claim 1, wherein the finger-hanging recess is located radially outward of the mounting groove and above the innermost end of the first recess.

3. 2. The cap according to claim 1, wherein the width of the first lightening groove in the radial direction is greater than the height from the inner periphery of the outer cylinder to the inner tip of the engaging protrusion in the radial direction.

4. A second lightening groove having an open bottom is formed in the outer cylinder, the first lightening groove is disposed on the opposite side of the hinge with respect to the axis of the cap; 2. The cap according to claim 1, wherein the second recessed groove is disposed on a side closer to the hinge with respect to an axis of the cap.

5. The cap body has a top wall that covers the mouth of the container, The outer cylinder has a fixed portion provided on the outer peripheral edge of the top wall and a detachable portion connected to the fixed portion via a breakable weakened portion, 2. The cap according to claim 1, wherein the detachable portion is provided with a hinge.

6. A manufacturing method for manufacturing the cap according to any one of claims 1 to 5 by injection molding, comprising: In a demolding process, the synthetic resin material solidified in the mold is released from the mold. The first core having the first lightening groove formed therein is released from the mold; Next, the second core forming the inner periphery of the outer cylinder is released from the mold. The method for manufacturing a cap is characterized in that the third core forming the finger-hanging recess is then released from the mold.

Images