HEAT INSULATING SLEEVE

Abstract

 An object of the present invention is to provide a heat-insulating sleeve with reduced deformation possibility of short strips resulting from interference at lock-forming portions. Part of the heat-insulating sleeve 120 above or below a plurality of short strips 121 and 122 is slid to cause the short strips 121 and 122 to bend or curve and to project radially outward, thereby creating a heat-insulating grip. The short strips 121 and 122 include alternately arranged first short strips 121 and second short strips 122. At least one of slits 130 has a lock-forming portion 131 that is to form a projected portion 127 and a recessed portion 128 in the short strips 121 and 122. The short strips 121 and 122 each include a constricted portion having a left-to-right width set smaller than the widths of parts located above or below same. Mountain folds 124 and 126 are formed in the respective constricted portions of the short strips 121 and 122.

Description

[Technical Field]

[0001] The present invention relates to a heat-insulating sleeve attached to an body outer circumferential surface of a container main body.

[Background Art]

[0002] A heat-insulating container has been known, which is formed by a container main body having a body and a bottom, and a heat-insulating sleeve fitted on the body outer circumferential surface of the container main body. The heat-insulating sleeve includes a plurality of slits that form a plurality of short strips extending in an up-and-down direction in a predetermined area in the height direction. Part of the heat-insulating sleeve above or below the short strips is slid so as to cause the plurality of short strips to bend or curve and to project radially outward, thereby creating a heat-insulating grip. The applicant of the present invention has proposed, with notable results, such heat-insulating containers in Japanese Patent No. 4294579 (PTL 1) and Japanese Patent No. 4391908 (PTL 2) in which the short strips are transformed into a heat-insulating grip by manually pushing up or down the heat-insulating sleeve.

[0003] It is essential with these heat-insulating containers that, after the plurality of short strips have been bent or curved and projected radially outward to form the heat-insulating grip, these projected parts should be spaced apart from the container main body so that no heat is conducted to the hand holding the projected parts, i.e. the plurality of short strips must not return to their original shape. When the heat-insulating sleeve is slid and maintained in that state only with friction or gravity, the plurality of short strips could return to their original shape when the container is gripped hard, which would result in reduced heat-insulating effect. There is also a risk in that the projected parts of the short strips could be deformed when gripped, causing the container to drop from the hand. For these reasons, these known heat-insulating containers adopt various configurations to mitigate the shortcomings, such as an increase in the length of the short strips in the height direction such that the strips be folded in a non-reversible manner when the sleeve is slid, a complex crease pattern for maintaining the projection as much as possible when the container is gripped, and an additional retainer component provided for keeping the short strips projected.

[0004] However, as a result of these known heat-insulating containers incorporating the structures or mechanisms described above, larger movements are required for pushing up or down the heat-insulating sleeve, additional action is required, or other similar problems are created which make it impossible to form the heat-insulating grip in a simple manner. Besides, the provision of the structures or mechanisms described above also led to the problems of increased work and cost for manufacture and assembly.

[0005] As an invention for solving the problems described above, the applicant of the present invention has proposed WO 2012/160682 (PTL 3). The heat-insulating container 500 of PTL 3 includes a plurality of alternately arranged short strips 521 and 522 as shown in Fig. 10, the first short strips 521 having a valley fold 523 at the top end and a mountain fold 524 in an upper area, and the second short strips 522 having a valley fold 525 at the bottom end and a mountain fold 526 in a lower area. At least one of a plurality of slits 530 includes a lock-forming portion (bent portion) 531 that provides projected portions 527 and recessed portions 528 in the short strips 521 and 522. When part of the heat-insulating sleeve 520 above or below the short strips 521 and 522 is slid to create a heat-insulating grip on the heat-insulating sleeve 520, the opposing projected portions 527 of short strips 521 and 522 arranged side by side slide up and down and override each other to be locked in this state, so that the plurality of short strips 521 and 522 are kept projected even when the outer side of the container is gripped.

[Citation list]

[Patent Literature]

[0006] 

[PTL 1] Japanese Patent No. 4294579 (entire text, all drawings)

[PTL 2] Japanese Patent No. 4391908 (entire text, all drawings)

[PTL 3] WO 2012/160682

[Summary of Invention]

[Technical Problem]

[0007] However, with the heat-insulating container 500 of PTL 3, when the heat-insulating sleeve 520 is slid in the up-and-down direction to create a heat-insulating grip on the heat-insulating sleeve 520, there were problems associated with interference (unexpected catch) occurring at the lock-forming portions 531, such as folding or deformation of unintended portions (e.g., parts A in Fig. 10) other than the mountain folds 524 and 526 or valley folds 523 and 525, or folding of short strips in the opposite direction from the predetermined direction at the mountain folds 524 and 526 or valley folds 523 and 525, these being caused by forces that are generated when the heat-insulating sleeve 520 is slid and are applied to the short strips 521 and 522, with interference occurring at the lock-forming portions 531.

[0008] Accordingly, the present invention is directed to solve these problems, and an object thereof is to provide a heat-insulating sleeve with reduced possibility of short strips becoming deformed due to interference at lock-forming portions.

[Solution to Problem]

[0009] The present invention provides a heat-insulating sleeve attached to an body outer circumferential surface of a container main body, including a plurality of slits to form a plurality of short strips extending in an up-and-down direction in a predetermined area in a height direction, the plurality of short strips being bent or curved to project radially outward, thereby creating a heat-insulating grip. The plurality of short strips include a first short strip having a valley fold at a top end and a mountain fold in an upper area, and a second short strip having a valley fold at a bottom end and a mountain fold in a lower area, the first and second short strips being arranged alternately to each other. At least one of the slits has a lock-forming portion that is to form a projected portion and a recessed portion in the short strip in a middle part between the mountain folds of left and right short strips. The short strips each include a constricted portion having a left-to-right width set smaller than widths of upper and lower parts, and the mountain fold is formed in the constricted portion of each of the short strips. The problems described above are thereby solved.

[Advantageous Effects of Invention]

[0010] With the invention according to claim 1, the short strips each include a constricted portion having a left-to-right width set smaller than widths of upper and lower adjacent parts, and the mountain fold is formed in this constricted portion of the short strips, so that parts of the heat-insulating sleeve can easily bend at the mountain folds when the sleeve is slid in the up-and-down direction to create the heat-insulating grip. Also, because of the constricted portion, the short strips can readily twist (incline relative to the thickness direction of the sleeve), so that any interference that may occur at the lock-forming portion can easily be cancelled, and thus the possibility of the short strips becoming deformed due to interference at the lock-forming portion is reduced.

[0011] With the invention according to claim 2, by setting the left-right width of the mountain fold smaller than the distance between a left-side imaginary line and a right-side imaginary line in a direction in which the mountain fold extends, the short strips can readily bend and twist at the mountain fold.

[0012] With the invention according to claim 3, by forming a cut at least at one of left and right ends of the mountain fold, the connecting portion of the mountain fold can have an even smaller width. Moreover, the short strip can bend at the mountain fold even more reliably since forces applied to the heat-insulating sleeve when the heat-insulating sleeve is slid up and down can readily concentrate at the mountain fold where the cut has been formed.

[0013] With the invention according to claim 4, the connecting portion of the mountain fold has a width that is the smallest of all other widths of various parts of the short strip, so that the short strip can bend at the mountain fold more easily than in other parts of the short strip.

[0014] With the invention according to claim 5, the slits without the lock-forming portion include a curved portion at least in part, so that a constricted portion where the left-right width is reduced can readily be formed in each short strip. Moreover, a lateral force is generated between short strips on both left and right sides of a slit at the curved portion of the slit when the heat-insulating sleeve is slid up and down to form the heat-insulating grip, which lateral force facilitates the opposing projected portions of the short strips on both sides of the slit to slide in the up-and-down direction and override each other, so that favorable interlocking is achieved at the lock-forming portion. Furthermore, the curved portion, by its contour, allows for finer adjustment of how much the short strips will be inclined when they project out, or how much side faces of adjacent short strips approach or separate from each other, so that the material, thickness, short strip shape, etc. of the heat-insulating sleeve can be designed more freely in accordance with the forms and purposes of containers as required.

[0015] With the invention according to claim 6, a crease is made at least at one of the mountain fold and valley fold, so that, in forming the heat-insulating grip, respective parts can easily bend in predetermined directions at the mountain folds and valley folds.

[Brief Description of Drawings]

[0016] 

[Fig. 1]
Fig. 1 is a side view illustrating a heat-insulating container that is one embodiment of the present invention.

[Fig. 2]
Fig. 2 is a side view illustrating a heat-insulating sleeve.

[Fig. 3]
Fig. 3 is an illustrative diagram for explaining the width of an upper mountain fold of a first short strip.

[Fig. 4]
Fig. 4 is an illustrative diagram for explaining the width of a lower mountain fold of a second short strip.

[Fig. 5]
Fig. 5 is a plan view illustrating a blank sheet of the heat-insulating sleeve in a developed state.

[Fig. 6]
Fig. 6 is an illustrative diagram showing a first step of making a crease in the heat-insulating sleeve.

[Fig. 7]
Fig. 7 is an illustrative diagram showing a second step of making a crease in the heat-insulating sleeve.

[Fig. 8]
Fig. 8 is an illustrative diagram showing a third step of making a crease in the heat-insulating sleeve.

[Fig. 9]
Fig. 9 is a schematic diagram illustrating the heat-insulating sleeve after creases have been made.

[Fig. 10]
Fig. 10 is a side view illustrating a conventional heat-insulating container.

[Reference Signs List]

[0017] 

100

Heat-insulating container

110

Container main body

111

Body

113

Opening

112

Bottom

120

Heat-insulating sleeve

121

First short strip

122

Second short strip

123

Upper valley fold

124

Upper mountain fold

125

Lower valley fold

126

Lower mountain fold

127

Projected portion

128

Recessed portion

130

Slit

131

Lock forming portion

132

Side seam

133a

First left-side slit portion

133b

First right-side slit portion

134a

First left-side connecting portion

134b

First right-side connecting portion

135a

Second left-side slit portion

135b

Second right-side slit portion

136a

Second left-side connecting portion

136b

Second right-side connecting portion

140

Receiver

141

Tapered inner circumferential surface

142

Mold surface

150

Inner core

151

Tapered outer circumferential surface

152

Raised part

160

Push-up member

LL

Left-side imaginary line

RL

Right-side imaginary line

[Description of Embodiments]

[0018] Hereinafter, a heat-insulating container 100 that is one embodiment of the present invention will be described with reference to the drawings.

[0019] The heat-insulating container 100 is formed by a container main body 110 including a body 111 and a bottom 112, and a heat-insulating sleeve 120 attached to an outer circumferential surface of the body 111 of the container main body 110, as shown in Fig. 1.

[0020] The heat-insulating sleeve 120 is made of paper or plastic and fixed (more specifically, bonded) to the outer circumferential surface of the body 111 only at the opening 113 at the top of the container. As shown in Fig. 1, a plurality of slits 130 are provided in the heat-insulating sleeve 120 to form a plurality of short strips 121 and 122 extending in the up-and-down direction in a predetermined area in the height direction.

[0021] The lowermost end of the heat-insulating sleeve 120 projects over a predetermined height relative to the lowermost end of the container main body 110 as shown in Fig. 1, and the heat-insulating sleeve 120 is configured to be able to slide such as to allow the short strips 121 and 122 to bend or curve by the amount equal to this height.

[0022] The plurality of short strips 121 and 122 include first short strips 121 and second short strips 122 alternately arranged adjacent each other in the circumferential direction, the first short strips 121 having a lower valley fold 125 at the bottom and a lower mountain fold 126 in a lower area, and the second short strips 122 having an upper valley fold 123 at the top and an upper mountain fold 124 in an upper area as shown in Fig. 2. The valley folds 123 and 125 and mountain folds 124 and 126 are each formed straight. The short strips 121 and 122 each include a constricted portion where the left-right width is smaller than those of the upper and lower adjacent parts, and the mountain folds 124 and 126 are provided in the constricted portions of the short strips 121 and 122.

[0023] The mountain folds 124 and 126 each include, as shown in Fig. 2, a connecting portion 124a or 126a that connects upper and lower portions, and cuts 124b or 126b formed at left and right edges of each of the mountain folds 124 and 126. Taking into consideration both aspects of the bendability at the mountain folds 124 and 126 and the strength of the mountain folds 124 and 126, the width of the connecting portions 124a and 126a should preferably be set about 10 to 20% of the width of the mountain folds 124 and 126. The connecting portions 124a and 126a should preferably be positioned at the center of the mountain folds 124 and 126. The cuts 124b and 126b may be formed only at one of the left and right edges of the mountain folds 124 and 126. Alternatively, additional cuts may be provided midway of the connecting portions 124a and 126a.

[0024] As shown in Fig. 3 and Fig. 4, the width W1 of each mountain fold 124 or 126 is set shorter than the distance W2 between a left-side imaginary line LL and a right-side imaginary line RL in the direction in which each mountain fold 124 or 126 extends.

[0025] The left-side imaginary line LL and right-side imaginary line RL are defined as follows:

First, the left-side slit 130 of the short strip 121 or 122 includes: a first left-side slit portion 133a formed near the valley fold 123 or 125 of the short strip 121 or 122; a first left-side connecting portion 134a connecting the valley fold 123 or 125 of the short strip 121 or 122 and the first left-side slit portion 133a; a second left-side slit portion 135a formed near the valley fold 123 or 125 of a short strip 121 or 122 positioned on the left side of the short strip in question; and a second left-side connecting portion 136a connecting the valley fold 123 or 125 of the short strip 121 or 122 on the left side of the short strip in question and the second left-side slit portion 135a.

[0026] Similarly, the right-side slit of the short strip 121 or 122 includes: a first right-side slit portion 133b formed near the valley fold 123 or 125 of the short strip 121 or 122; a first right-side connecting portion 134b connecting the valley fold 123 or 125 of the short strip 121 or 122 and the first right-side slit portion 133b; a second right-side slit portion 135b formed near the valley fold 123 or 125 of a short strip 121 or 122 positioned on the right side of the short strip in question; and a second right-side connecting portion 136b connecting the valley fold 123 or 125 of the short strip 121 or 122 on the right side of the short strip in question and the second right-side slit portion 135b.

[0027] As shown in Fig. 3 and Fig. 4, these portions of slits 133a, 133b, 135a, and 135b are each formed by a curve of a predetermined curvature or a straight line extending substantially in the up-and-down direction, and connected to the valley folds 123 and 125 extending substantially in the left-to-right direction via the curved connecting portions 134a, 134b, 136a, and 136b. Note, the connecting portions 134a, 134b, 136a, and 136b may be formed by straight lines, or by a combination of straight and curved lines.

[0028] As shown in Fig. 3 and Fig. 4, the left-side imaginary line LL refers to a line connecting: an intersection between an imaginary extension line of the first left-side slit portion 133a and an imaginary extension line of the valley folds 123 and 125 of the short strips 121 and 122; and an intersection between an imaginary extension line of the second left-side slit portion 135a and an imaginary extension line of the valley folds 123 and 125 of short strips 121 and 122 that are located on the left side of the short strip in question.

[0029] As shown in Fig. 3 and Fig. 4, the right-side imaginary line RL refers to a line connecting: an intersection between an imaginary extension line of the first right-side slit portion 133b and an imaginary extension line of the valley folds 123 and 125 of the short strips 121 and 122; and an intersection between an imaginary extension line of the second right-side slit portion 135b and an imaginary extension line of the valley folds 123 and 125 of short strips 121 and 122 that are located on the right side of the short strip in question.

[0030] The connecting portions 124a and 126a of the mountain folds 124 and 126 are formed to have a smallest of the widths of various parts of the short strips 121 and 122 having those mountain folds 124 and 126.

[0031] The plurality of slits 130 include those with a lock-forming portion 131 and those without the lock-forming portion 131, these being alternately arranged in the circumferential direction. The lock-forming portion 131 of the slit 130 forms projected portions 127 and recessed portions 128 in the short strips 121 and 122 on both left and right sides in a middle part between the upper mountain folds 124 and lower mountain folds 126 of the left and right short strips 121 and 122. In this embodiment, the slit 130 formed between the left side of the first short strip 121 and the right side of the second short strip 122, when the container is set up and viewed from the front, is defined as the slit 130 having the lock-forming portion 131.

[0032] As shown in Fig. 2, two each projected portions 127 and recessed portions 128 are formed alternately up and down, e.g., the second short strip 122 has, from the top, the projected portion 127 (recessed portion 128 of the first short strip 121), recessed portion 128 (projected portion 127 of the first short strip 121), projected portion 127 (recessed portion 128 of the first short strip 121), and recessed portion 128 (projected portion 127 of the first short strip 121).

[0033] The slits 130 without the lock-forming portion 131 are formed by curves, as shown in Fig. 2. The slits 130 without the lock-forming portion 131 may be formed by a combination of straight and curved lines.

[0034] Next, the method of producing the heat-insulating sleeve 120 will be described below.

[0035] First, glue is applied to the side seam 132 of a blank sheet 120' that is obtained by punching as shown in Fig. 5, and the blank sheet 120' is rolled into a tube and the side seam 132 is compressed to bond the ends together, to thereby form the tubular heat-insulating sleeve 120 shown in Fig. 2.

[0036] Next, as shown in Fig. 6, the heat-insulating sleeve 120 is set on a receiver 140 that has a tapered inner circumferential surface 141 with its diameter increasing upward, and an inner core 150 that has a tapered outer circumferential surface 151 with its diameter increasing upward is inserted into the heat-insulating sleeve 120 from above the heat-insulating sleeve 120 as shown in Fig. 7, so as to fix the heat-insulating sleeve 120 in the receiver 140.

[0037] Next, as shown in Fig. 8, the heat-insulating sleeve 120 is pushed up with a push-up member 160 so as to make the lower part of the heat-insulating sleeve 120 slide upward, whereby respective parts of the heat-insulating sleeve 120 are bent in predetermined directions at the valley folds 123 and 125 and mountain folds 124 and 126, as shown in Fig. 9. The tapered inner circumferential surface 141 of the receiver 140 includes a mold surface 142 in the shape corresponding to the heat-insulating grip projecting radially outward of the heat-insulating sleeve 120 as shown in Fig. 6, while the tapered outer circumferential surface 151 of the inner core 150 includes a raised part 152 slightly bulged radially outward, so that the respective parts are prevented from bending oppositely from the predetermined directions at the valley folds 123 and 125 and mountain folds 124 and 126. In the embodiment described above, creases are made in advance both at the valley folds 123 and 125 and mountain folds 124 and 126, but creases may be made only at the valley folds 123 and 125 or at the mountain folds 124 and 126.

[0038] While every other one of the circumferentially arranged slits 130 has the lock-forming portion 131 in this embodiment, every two (or even more) slits may have a lock-forming portion, as long as the heat-insulating sleeve 120 can slide upward and remain in the state where the first short strips 121 and second short strips 122 project outward. Alternatively, all the slits 130 may have the lock-forming portion 131.

[0039] In the description described above, to create the heat-insulating grip on the heat-insulating sleeve, the lower part of the heat-insulating sleeve is made to slide upward from the initial state. Instead, the heat-insulating sleeve may be set such as to have its bottom end resting on a horizontal surface, and the upper part of the heat-insulating sleeve or the container main body 110 may be pushed down and made to slide.

[Industrial Applicability]

[0040] The heat-insulating container of the present invention is manufactured and assembled easily with reduced cost and allows formation of a heat-insulating grip with a simple operation. The short strips remain projected even when gripped from the outer side so as to reliably maintain the heat-insulating effect and allow for secure grip without the worry of deformation. The container can therefore favorably be used as a cup-shaped container for containing instant food that is heated with a microwave or hot water when consumed. Moreover, because of its ability to transform to acquire a uniquely designed look with a simple operation, the sleeve is not only limited to heat-insulating applications but can be used for various cup-shaped containers.

Claims

1. A heat-insulating sleeve attached to an body outer circumferential surface of a container main body, comprising:

a plurality of slits to form a plurality of short strips extending in an up-and-down direction in a predetermined area in a height direction, said plurality of short strips being bent or curved to project radially outward, thereby creating a heat-insulating grip, said plurality of short strips including a first short strip having a valley fold at a top end and a mountain fold in an upper area, and a second short strip having a valley fold at a bottom end and a mountain fold in a lower area, the first and second short strips being arranged alternately to each other,

at least one of said slits having a lock-forming portion that is to form a projected portion and a recessed portion in said short strip in a middle part between the mountain folds of left and right short strips,

said short strips each including a constricted portion having a left-to-right width set smaller than widths of upper and lower adjacent parts, and

said mountain fold being formed in the constricted portion of each of said short strips.

2. The heat-insulating sleeve according to claim 1, wherein a left-side slit of said short strip includes a first left-side slit portion formed near the valley fold of said short strip and a second left-side slit portion formed near the valley fold of a short strip located on the left side of said short strip,
a right-side slit of said short strip includes a first right-side slit portion formed near the valley fold of said short strip and a second right-side slit portion formed near the valley fold of a short strip located on the right side of said short strip, and when
a line connecting an intersection between an imaginary extension line of said first left-side slit portion and an imaginary extension line of the valley fold of said short strip, and an intersection between an imaginary extension line of said second left-side slit portion and an imaginary extension line of the valley fold of the short strip located on the left side of said short strip is defined as a left-side imaginary line, and
a line connecting an intersection between an imaginary extension line of said first right-side slit portion and an imaginary extension line of the valley fold of said short strip, and an intersection between an imaginary extension line of said second right-side slit portion and an imaginary extension line of the valley fold of the short strip located on the right side of said short strip is defined as a right-side imaginary line,
said mountain fold has a left-right width that is set shorter than a distance between said left-side imaginary line and said right-side imaginary line in a direction in which said mountain fold extends.

3. The heat-insulating sleeve according to claim 1 or 2, wherein said mountain fold includes a connecting portion that connects upper and lower parts, and a cut formed at least at one of left and right ends of said mountain fold.

4. The heat-insulating sleeve according to any one of claims 1 to 3, wherein a connecting portion of said mountain fold has a width that is smallest of all other widths of various parts of the short strip in which this mountain fold is formed.

5. The heat-insulating sleeve according to any one of claims 1 to 4, wherein said plurality of slits include slits having said lock-forming portion and slits without said lock-forming portion,
said slits without said lock-forming portion including a curved portion at least in part.

6. The heat-insulating sleeve according to any one of claims 1 to 5, wherein a crease is made at least at one of said mountain fold and said valley fold.

Drawing