Patent Application
20210261290
The present invention relates to a tab for opening a can lid.
A can lid having an opening tab of stay-on type is commonly known. Such a can lid has a tab fixed to a panel of a can lid body, and the tab includes: a fixed part fixed to the can lid body by a rivet; a pulling-up part separated from the fixed part due to a slit and pulled up by a finger; and a pressing-down part pressed down in accordance with pulling up of the pulling-up part, with the fixed part serving as a fulcrum, and moreover the can lid opens as a score formed at the panel is ruptured by the pressing-down part of the tab so that an opening piece demarcated by the score sinks into the can.
In such a tab for opening a can lid, force that is exerted on a finger during opening operation is reduced by making use of principle of leverage, according to which the fixed part serves as a fulcrum, the pulling-up part serves as a point of lever, and the pressing-down part serves as a point of action. The length from the fixed part to the pulling-up part is greater than the length from the fixed part to the pressing-down part. Moreover, a curl part is formed for increasing rigidity at a peripheral edge of the tab, which connects the pulling-up part and the pressing-down part, so that the pressing-down part is pressed down synchronously with pulling up of the pulling-up part.
In general, a hole, which is called a finger hole, is formed between the fixed part and the pulling-up part of the tab. Meanwhile, a tab with no finger hole between the pulling-up part and the fixed part is also known (see PTL 1). Such a tab may be provided with a tab panel between the fixed part and the pulling-up part, whereby information or a picture is indicated at a part thereof to be able to enhance decorativeness.
The abovementioned tab is produced from a strip-shaped coil on which a plurality of tabs are continuously arranged. At the time of producing the same, the tabs are shaped by blanking from the strip-shaped coil through multiple steps, in which the coil is, first, subjected to necessary hole machining, then, the contour shape of each tab is blanked along an annular cut line excluding a connected-piece, which is to be a so-called carry-point, and, thereafter, necessary tab shape processing, such as irregularity shaping or curl shaping that is implemented to peripheral edges, is performed in a state where the plurality of tabs are continuously arranged on the coil, and eventually the connected-piece is severed so that the tab is attached to a can lid body.
In this case, if the connected-piece, which is to be the carry point is present both on the left and right sides of the fixed part, the curl part provided at the peripheral edge is interrupted in the position of the connected-piece, and the rigidity of the tab is reduced in the interrupted position. Therefore, in the abovementioned conventional case with no finger hole between the fixed part and the pulling-up part, when the pulling-up part is pulled up during opening operation, the interrupted part of the curl part in the position of the connected-piece becomes a bending point, which causes the tab to be easily bent, whereby the tab may not have enough rigidity necessary for opening.
The opening tab of stay-on tab-type is a part to which a person holding a can pays particular attention during opening operation, and the tab is not severed from a can lid body after opening, hence, by providing to a part of the tab an indication of information or a picture, it is possible to enhance decorativeness as described above and provide information or advertisement effectively.
The indication at the tab may be implemented effectively in a case where a finger hole between the fixed part and the pulling-up part is removed. However, when indication is implemented between the fixed part and the pulling-up part by, for example, laser marking or ink jet printing and a tab panel is shaped to have a downwardly convex surface as in the conventional case, the tool surface of a shaping tool contacts a surface that is provided with the indication, and dust generated during laser marking or ink from ink jet printing is transferred onto the tool surface, and this may disturb the indication on the tab itself or, during processing on other tabs arranged continuously on the strip-shaped coil, dust or ink transferred onto the tool surface of the shaping tool may be transferred to the other tabs, which results in disturbing the indication on the other tabs.
Moreover, in tab production, the peripheral edge of the tab is subjected to curl shaping as described above, and during this processing, a curve may be created in the fixed part of the tab and the pulling-up part of the tab, hence the curve needs to be subjected to reform shaping to flatten the same. At that time, when there is an indication made by laser marking or ink jet printing between the curved fixed part and the curved pulling-up part, the dust or ink is transferred to the tool surface of a shaping tool that performs reform shaping, and this may cause a problem same as described above.
In a case where no finger hole is provided, and the upper surface is formed having a downwardly convex shape, a finger contacts the tab panel when pulling up the pulling-up part during opening operation, hence favorable operational feeling cannot be obtained.
The present invention has been proposed to address such problem. More specifically, it is an object of the present invention that, in a case where an indication is provided between a fixed part and a pulling-up part of a tab, the tab is provided with necessary rigidity, indication disturbance is reduced, and favorable operational feeling is provided during opening.
In order to solve the problems, a tab for opening a can lid according to the present invention includes the following configuration.
A tab for opening a can lid, the tab including a pulling-up part provided on one end side in a longitudinal direction of the tab, a pressing-down part provided on another end side in the longitudinal direction, a fixed part provided between the pulling-up part and the pressing-down part and formed by being demarcated by a U-shaped slot and fixed to a can lid body, and a curl part formed continuously at a peripheral edge excluding a connected-piece-cutting trace at the pressing-down part, wherein a surface between the fixed part and the pulling-up part is a display surface, and a back surface side of the display surface is an abutted surface against which a shaping tool is abutted.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference characters among different figures indicate portions having the same functions, and their description in connection with the drawings will not be repeated as appropriate. The direction of the arrow X in
As shown in
A person engaged in opening operation puts a finger on the pulling-up part 2, and the opening operation is performed by pulling up the part in the Z direction in illustrations. As the pulling-up part 2 is pulled up, the pressing-down part 3 is pressed down in the opposite direction, and when the pressing-down part is pressed down in abutment against the panel of the can lid body, the score of the can lid is ruptured.
The fixed part 4 is formed by being demarcated by a U-shaped slot 5 and includes a rivet hole 6 through which a rivet to be provided on the panel of the can lid body is inserted, and the fixed part 4 is fixed to the can lid body as the rivet is inserted into the rivet hole 6 and crimped.
A connected-piece-cutting trace 7 is provided in the center of the pressing-down part 3. Then, a curl part 8 is formed on the outer peripheral edge of the tab 1 excluding the connected-piece-cutting trace 7. The curl part 8 increases the flexural rigidity of the tab 1 because the tab 1 serves as a lever having the pulling-up part 2 as a point of effort, the fixed part 4 as a fulcrum point, and the pressing-down part 3 as a point of load. Here, the connected-piece-cutting trace 7 is provided at the pressing-down part 3, so that the interrupted part of the curl part 8 is in a position free from bending force caused when the pulling-up part 2 is pulled up during opening operation, and the tab 1 has rigidity necessary for opening the can lid.
The tab 1 (1A, 1B, or 1C) is shaped. In one case, a shaped part 10 having a convex shape in the direction opposite to the Z direction is provided on the periphery of the fixed part 4, and the region between the pulling-up part 2 and the fixed part 4 is shaped. The tab 1 (1A) shown in
Tab 1 (1A, 1B, or 1C) includes a display surface 20. Although not shown, the display surface 20 is the surface between the pulling-up part 2 and the fixed part 4 which is formed with a display part for example for a two-dimensional code, a logo, a picture, letters, and numbers drawn by laser marking or ink jet printing. The back surface side of the display surface 20 is an abutted surface 21 for performing the shaping processing as described above. A shaping tool for shaping the shaped parts 11 and 12 or reform shaping in
The can lid to which the tab 1 is attached is produced as shown in
As shown in
The shaping tool 41 is made to abut against the abutted surface 21 of the tab material T, and the shaping tool 41 is pressed into the die hole 40A, so that the shaped part 11 is shaped inside the die hole 40A as shown in
The tab material T passed through the tab shaping machine 31 is sent to a conversion press 32 shown in
Table 1 gives a sensory evaluation result about opening operation according to the embodiment illustrated in
The sensory evaluation test about opening operation was performed, and in the test, a can lid provided with a tab 1 according to the embodiment was designated as example 1 (the can lid provided with the tab 1 having the display surface 20 on the surface side, the abutted surface 21 on the back surface side, and the upwardly convex shaped part 11 formed), a can lid identical to example 1 except for the flat shaped part 11 was designated as example 2, and a can lid identical to example 1 except for the downwardly convex shaped part 11 was designated as example 3.
During opening operation in the sensory evaluation test, the finger is first inserted into the gap between the tab 1 and the lid surface while the finger tip touches the tab 1, then the finger is guided toward the abutted surface 21 of the tab 1 while, at the same time, the tab 1 is lifted by the finger to initially open the can. Then, the inside of the finger is firmly pressed against the abutted surface 21 of the tab 1 and the tab 1 is lifted by the inside of the finger, so that the opening piece defined by the score of the can lid body is pressed down.
In the sensory evaluation test, the tab 1 was lifted up by the inside of the finger in each of examples 1 to 3, and awkward feeling experienced when pressing down the opening piece defined by the score of the can lid body was relatively evaluated. In example 1 with the tab formed with the upwardly convex shaped part 11 or example 2 with the tab formed with the flat shaped part 11, the distance S1 (see
In the sensory evaluation test the evaluation indexes with reference to example 3 include “⊚” which represents very good operational feeling in pulling up the tab with less awkwardness than example 3, “◯” which represents good operational feeling in pulling up the tab with less awkwardness than example 3, and “Δ” which represents feeling with a little more awkwardness than example 3.
As can be clearly understood from Table 1, in example 1 (with the upwardly convex shaped part 11) and example 2 (with the flat shaped part 11), generally good operational feeling with less awkwardness resulted than that in example 3 (with the downward convex shaped part 11). More specifically, when the display part T1 is provided on the surface side in the tab 1 and the upwardly convex shaped part 11 is shaped while the shaping tool is abutted thereupon from the back surface side or when the part between the pulling-up part and the fixed part is shaped to be flat, the display part T1 with no disturbance as well as good operational feeling in opening operation can be obtained. The connected-piece T4 is positioned at the pressing-down part, and necessary rigidity for the tab 1 can be obtained.
The embodiments of the present invention have been described in detail with reference to the drawings, while specific configurations are not limited by these embodiments and design changes not departing from the gist of the present invention are encompassed by the present invention. These embodiments can divert and combine their features with one another if there is no particular inconsistency or problem in relation to the purposes and structures of the features.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-119888 | Jun 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/023529 | 6/13/2019 | WO | 00 |
