Can lid manufacturing device, can lid manufacturing method, can lid, and can container with contents

Abstract

To provide a can lid manufacturing device, a can lid manufacturing method, a can lid, and a can container containing contents, which improve the opening property and pressure resistance of a can lid with a simple configuration. [Solution] A can lid manufacturing apparatus 10 that produces can lids L, comprising a rolling direction detection unit 50 having a rotation drive unit 51 that rotates the can lids L and a reflected light detection unit 52, and a control unit, wherein the reflected light detection unit 52 has a light emitting unit 52a and a light receiving unit 52b, and the control unit is configured to detect the rolling direction of the can lids L based on information on changes in the light intensity of the reflected light reflected by the rotating can lids L obtained by the rolling direction detection unit 50.

Description

[Technical field]

[0001] The present invention relates to a can end manufacturing apparatus, a can end manufacturing method, a can end, and a can container containing a content. [Background technology]

[0002] Conventionally, it has been generally known to use metal can containers as containers for holding contents such as beverages (see, for example, Patent Document 1), and it is also well known that the can lids constituting such can containers are formed from rolled metal plates formed by rolling processing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4239039 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it has been found that in can lids formed from such rolled metal sheets, the relationship between the rolling direction of the can lid (i.e., the direction in which the roll marks formed in the rolled metal sheet extend) and the direction in which the scores or the like are formed on the can lid affects the openability of the can lid (i.e., the force required to break the score) and pressure resistance.

[0005] Therefore, an object of the present invention is to provide a can lid manufacturing device, a can lid manufacturing method, a can lid, and a can container containing contents, which have a simple configuration and improve the openability and pressure resistance of can lids. [Means for solving the problem]

[0006] The can lid manufacturing apparatus of the present invention is a can lid manufacturing apparatus that manufactures can lids, and is equipped with a rolling direction detection unit having a rotation drive unit that rotates the can lids and a reflected light detection unit, and a control unit. The reflected light detection unit has an emitter that irradiates light onto the can lids, and a light receiver that receives reflected light from the irradiated light reflected by the can lids. The control unit is configured to detect the rolling direction of the can lids based on information on changes in the light intensity of the reflected light reflected by the rotating can lids, obtained by the rolling direction detection unit, thereby solving the above problem. The can lid manufacturing method of the present invention is a can lid manufacturing method for manufacturing can lids, and includes a rolling direction detection unit having a rotation drive unit for rotating the can lid and a reflected light detection unit, and a control unit. The reflected light detection unit has an emitter for irradiating light onto the can lid and a light receiver for receiving reflected light of the irradiated light reflected by the can lid. The control unit detects the rolling direction of the can lid based on information on changes in the light intensity of the reflected light reflected by the rotating can lid, obtained by the rolling direction detection unit, thereby solving the above problem. In the above can lid manufacturing apparatus (or can lid manufacturing method), the rolling direction detection unit may further include a rotational position adjustment unit that adjusts the rotational position of the can lid based on rolling direction information of the can lid obtained by the control unit. In any of the above can end manufacturing devices (or can end manufacturing methods), the rotation drive unit and the rotation position adjustment unit may be configured from the same equipment that rotates the can ends. Any of the above can lid manufacturing devices (or can lid manufacturing methods) may further include a can lid supplying machine that supplies can lids onto a conveying conveyor, the can lid supplying machine having a can lid storage section that stores multiple can lids in a stacked state, a can lid temporary storage section formed below the can lid storage section that stores one can lid, an upper side feed section that feeds the can lids stored in the can lid storage section to the can lid temporary storage section, and a lower side feed section that feeds the can lids that have been stored in the can lid temporary storage section toward the conveying conveyor, and the rolling direction detection unit may be installed to detect reflected light from the can lids that have been stored in the can lid temporary storage section. In any of the above can lid manufacturing devices (or can lid manufacturing methods), the can lid supplying machine includes a transfer rotor that can rotate around a vertical axis, and the transfer rotor has an upper engagement portion that can engage with the can lid and a lower engagement portion that is formed below the upper engagement portion and can engage with the can lid on its outer surface, and the upper engagement portion functions as the upper feed portion that feeds can lids stored in the can lid storage portion to the can lid temporary retention portion as the transfer rotor rotates, and the lower engagement portion functions as the lower feed portion that feeds can lids that have been retained in the can lid temporary retention portion toward the conveying conveyor as the transfer rotor rotates. In any of the above-mentioned can lid manufacturing apparatuses (or can lid manufacturing methods), the can lid temporary retention portion may be composed of an outer peripheral recess recessed into the outer peripheral surface of the transfer rotor in the area between the upper side engagement portion and the lower side engagement portion. In any of the above-mentioned can lid manufacturing apparatuses (or can lid manufacturing methods), the rolling direction detection unit may further include a rotational position adjustment unit that adjusts the rotational position of the can lid based on the rolling direction information of the can lid obtained by the control unit, and the rotational position adjustment unit may be configured to start adjusting the rotational position of the can lid at least in the can lid temporary retention section. In any of the above can lid manufacturing devices (or can lid manufacturing methods), the rotational position adjustment unit may be configured to adjust the rotational position of the can lid to a predetermined rotational position with an accuracy of within ±10°. In any of the above can end manufacturing devices (or can end manufacturing methods), the light emitting section of the reflected light detecting section may be disposed so as to irradiate light onto the chuck wall section of the can end from the outer periphery side. Any of the above can end manufacturing devices (or can end manufacturing methods) may further include an inspection machine that is installed downstream of the rolling direction detection unit and detects the orientation of the rolling direction of the can ends relative to the conveying direction of the can ends. The can end of the present invention is manufactured by any one of the above-mentioned can end manufacturing devices (or can end manufacturing methods), thereby solving the above-mentioned problems. In the can lid of the present invention, the can lid has a center panel portion, in which at least one sheet material deformation portion is formed by deforming a sheet material in the thickness direction, and the center panel portion has a narrow width portion which is the portion between the at least one sheet material deformation portion and the outer edge of the center panel portion where the distance between the sheet material deformation portion and the outer edge of the center panel portion is the narrowest, and the can lid may be formed such that a virtual line passing through the narrow width portion and the center of the center panel portion is parallel or approximately parallel to the rolling direction. The can container containing contents of the present invention solves the above-mentioned problem by being composed of the can lid and a can body filled with contents and around which the can lid is seamed. Effect of the Invention

[0007] According to the present invention, the openability and pressure resistance of a can lid can be improved with a simple structure. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram showing a can lid manufacturing apparatus according to an embodiment of the present invention. [Diagram 2] 1 is an explanatory diagram showing a can lid manufacturing apparatus according to an embodiment of the present invention, as viewed from the side; [Diagram 3] FIG. 4 is an explanatory diagram showing the peripheral configuration of a can lid temporary retention section. [Figure 4] FIG. 4 is an explanatory diagram showing the peripheral configuration of the can lid temporary retention portion as viewed from the side. [Diagram 5] FIG. [Figure 6] FIG. 2 is an explanatory diagram showing an example of a can lid. [Figure 7] 6 is a graph showing changes in the light intensity of detected reflected light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A can end manufacturing apparatus 10 and a can end manufacturing method according to an embodiment of the present invention will be described below with reference to the drawings. [Can lid]

[0010] First, the can lid L manufactured by the can lid manufacturing apparatus 10 and the can lid manufacturing method is made of a rolled metal plate formed by rolling processing of an aluminum alloy or the like, and is wrapped around the mouth of a metal can body (not shown) filled with contents when manufacturing a can container containing contents.

[0011] 6, the can lid L has an outer peripheral curled portion L1, a chuck wall portion L2 formed on the inner peripheral side of the outer peripheral curled portion L1, a center panel portion L4 located on the inner peripheral side of the chuck wall portion L2 and above the inner peripheral edge of the chuck wall portion L2, and a panel wall portion L3 connecting the chuck wall portion L2 and the center panel portion L4. Each portion L1, L2, and L3 of the can lid L is formed in an annular (circular ring) shape.

[0012] In addition, as shown in Figures 1 and 6(c), the center panel portion L4 is formed with a groove-shaped score (not shown) that functions as a weakened portion when the can lid L is opened, a rivet (not shown) for fixing a tab to the center panel portion L4, and an outer peripheral step portion L6 formed to surround the score (not shown). The outer peripheral step portion L6 is a portion where the plate material of the center panel portion L4 is deformed in the thickness direction so that the inner peripheral portion (recess panel) is one step lower than the outer peripheral portion, as shown in Figure 6(c). Note that Figures 6(a) and (b) show a can lid L in a state in which the above-mentioned scores (not shown), rivets (not shown), and outer peripheral step portion L6 have not been formed, and Figure 6(c) shows a can lid L in a state in which the scores (not shown) and rivets (not shown) have not been formed, and the outer peripheral step portion L6 has been formed.

[0013] Furthermore, with regard to the outer surface of the can lid L, the irradiated surface (in this embodiment, the chuck wall portion L2) onto which the irradiated light from the light-emitting portion 52a described below is applied, the metallic gloss surface of the rolled metal plate is exposed (or is coated with a coating that does not block light, such as transparent paint, ink or transparent resin) so as to reflect at least a portion of the irradiated light (at least at the time when the process of detecting the rolling direction of the can lid L using the irradiated light is performed).

[0014] In addition, since the can lid L is formed from a rolled metal plate, as shown in Fig. 6(b), countless roll marks L5, which are fine irregularities (rolling lines) extending in the rolling direction, are formed on the entire surface, including the irradiated surface, of the can lid L. Note that in Fig. 6(b), the irregularities of the roll marks L5 are greatly exaggerated. [Can lid manufacturing equipment]

[0015] Next, the can end manufacturing apparatus 10 of this embodiment will be described below.

[0016] First, the can end manufacturing apparatus 10 manufactures can ends L, and as shown in Figures 1 and 2, is equipped with a can end supplying machine 20 that supplies can ends L (in the process of being manufactured) one by one onto a conveying conveyor 30, the conveying conveyor 30 that conveys the can ends L supplied from the can end supplying machine 20, a can end processing machine 40 that is installed downstream of the conveying conveyor 30 and performs various processes such as scoring on the can ends L, a rolling direction detection unit 50 for detecting the rolling direction of the can ends L, an inspection machine 60 that is installed downstream of the rolling direction detection unit 50 and detects the orientation of the rolling direction of the can ends relative to the conveying direction of the can ends, and a control unit (not shown).

[0017] The can lid supplying machine 20 supplies can lids L onto the transport conveyor 30, and as shown in Figures 1 to 4, is equipped with a can lid storage section 21, a temporary can lid storage section 22 formed below the can lid storage section 21, a plurality of transport rotating bodies 23 that transport the can lids L downward, a plurality of rotational position maintaining sections 24 for maintaining the rotational position of the can lids L, and a plurality of guide poles 25 for guiding the can lids L.

[0018] As shown in Figs. 2 and 4, the can lid storage section 21 is a section for storing a plurality of can lids L in a piled up state (stacked state).

[0019] As shown in FIG. 4, the can lid temporary retention section 22 is a section below the can lid storage section 21 where one can lid L sent downward from the can lid storage section 21 is temporarily retained (placed). In this embodiment, as shown in Figure 4, the can lid temporary retention portion 22 is composed of an outer peripheral recess 23c recessed into the outer peripheral surface of the transfer rotor 23 in the area between the upper engagement portion 23a (the portion where the upper engagement portion 23a is formed) and the lower engagement portion 23b (the portion where the lower engagement portion 23b is formed) described later in the vertical direction.

[0020] The transfer rotor 23 is arranged to rotate (spin) about a vertical axis by a drive source such as a motor, and sends (moves) the can lid L downward as it rotates.As shown in Figure 4, the transfer rotor 23 has an upper engagement portion 23a that can engage with the can lid L (its outer peripheral curled portion L1), a lower engagement portion 23b that is formed below the upper engagement portion 23a with a gap therebelow and is capable of engaging with the can lid L (its outer peripheral curled portion L1), and its outer surface. The upper engagement portion 23a functions as an upper feed portion 23a that feeds the lowest can lid L among the can lids stored in the can lid storage portion 21 downward toward the can lid temporary retention portion 22 as the transfer rotor 23 rotates. In addition, the lower engagement portion 23b functions as a lower sending portion 23b that sends one can lid L retained in the can lid temporary retention portion 22 downward toward the transfer conveyor 30 as the transfer rotor 23 rotates.

[0021] In this embodiment, the upper side feed section 23a has been described as being composed of the upper side engagement section 23a, but the specific form of the upper side feed section 23a is not limited to this, and any form is acceptable as long as it is capable of cutting out a single can lid L from the can lid storage section 21 toward the can lid temporary retention section 22 and feeding it downward. Similarly, in this embodiment, the lower side feed portion 23b has been described as being composed of the lower side engagement portion 23b, but the specific form of the lower side feed portion 23b is not limited to this, and any form capable of feeding one can lid L downward from the can lid temporary storage portion 22 toward the conveying conveyor 30 is acceptable.

[0022] In addition, in this embodiment, the upper side engagement portion 23a and the lower side engagement portion 23b are configured as screw-shaped (spiral) grooves formed on the outer peripheral surface of the transfer rotor 23, but the specific form of the upper side engagement portion 23a and the lower side engagement portion 23b is not limited to this and may be any that is capable of sending the can lid L downward as the transfer rotor 23 rotates.

[0023] The rotational position maintaining section 24 maintains the rotational position of the can lid L when the can lid L is sent from the can lid temporary storage section 22 onto the transport conveyor 30, i.e., prevents the can lid L from rotating. In this embodiment, the rotational position maintaining section 24 is made of an elastic body such as synthetic resin or synthetic rubber, and as shown in Figure 4, it contacts the can lid L (its outer peripheral curled portion L1) to maintain the rotational position of the can lid L.

[0024] As shown in FIG. 4, the guide pole 25 extends in the vertical direction and guides the can lid L when the can lid L is moved in the vertical direction by the transfer rotor 23.

[0025] The transfer conveyor 30, as shown in FIGS. 1 and 2, transports the can lids L supplied from the can lid supplying machine 20. As shown in FIG. In this embodiment, the transport conveyor 30 is configured using a conveyor belt, but the specific form of the transport conveyor 30 may be any form capable of transporting the can lids L, such as a roller conveyor or a vacuum conveyor. In addition, in this embodiment, the transfer conveyor 30 is configured to pitch feed (intermittently move) the can lids L, but the specific embodiment of the transfer conveyor 30 may be any, such as one that continuously feeds the can lids L.

[0026] The can lid processing machine 40 is installed downstream of the can lid supply machine 20 and performs various processes on the can lids L transported by the conveyor 30, such as score processing to form scores (not shown), rivet processing to form rivets (not shown), and processing to form the outer peripheral step portion L6.

[0027] The rolling direction detection unit 50 detects the rolling direction of the can lid L and adjusts the rotation direction of the can lid L, and as shown in Figures 3 and 4, has a rotation drive unit 51 that rotates the can lid L, a reflected light detection unit 52, and multiple support rollers 53.

[0028] The rotation drive unit 51 rotates (spins) the can lids L retained in the can lid temporary retention unit 22 around an up-down axis, and in this embodiment is configured as a drive roller that is driven by a drive source such as a servo motor and can rotate (spin) around an up-down axis. At least the portion of the rotation drive part 51 that comes into contact with the can lid L is made of an elastic material such as urethane. As will be described in more detail later, the rotation drive unit 51 functions as a part that rotates the can lid L when detecting the rolling direction of the can lid L, and also functions as a rotation position adjustment unit 51 that adjusts the rotational position of the can lid L by positioning and stopping the can lid L at an appropriate rotational position based on rolling direction information of the can lid L obtained by a control unit (not shown). In other words, in this embodiment, the rotation drive unit 51 and the rotation position adjustment unit 51 are configured from the same equipment (drive roller, drive source) that rotates the can lid L. The specific embodiment of the rotation drive unit 51 and the rotation position adjustment unit 51 is not limited to being configured from the same equipment, and the rotation drive unit 51 and the rotation position adjustment unit 51 may be configured from different equipment.

[0029] As shown in Figure 3, the reflected light detection unit 52 has an emitter 52a that irradiates irradiation light (laser light in this embodiment) onto the can lids L retained in the can lid temporary retention section 22, and a light receiver 52b that receives and detects the reflected light reflected by the can lids L from the irradiated irradiation light.

[0030] As shown in FIG. 3(b), the light emitting unit 52a is disposed so as to irradiate light onto the chuck wall portion L2 (inclined so as to increase in diameter as it goes upward) of the can lid L from the outer periphery side. The portion of the can lid L onto which the light from the light emitting portion 52a is irradiated is not limited to the chuck wall portion L2, and may be, for example, the outer circumferential curled portion L1 or the like.

[0031] In this embodiment, as shown in FIG. 3(b), the light-emitting unit 52a is positioned above the light-receiving unit 52b; however, the relative positions of the light-emitting unit 52a and the light-receiving unit 52b are not limited to this, and any positional relationship may be used as long as at least a portion of the light emitted from the light-emitting unit 52a is reflected by the can lid L and at least a portion of the reflected light is received by the light-receiving unit 52b. Furthermore, as for the specific embodiment of the light receiving unit 52b, any embodiment may be used as long as it is capable of receiving the reflected light reflected by the can lid L and detecting the light intensity of the reflected light, such as, for example, one equipped with a light receiving element such as a laser sensor, or one equipped with an imaging element such as a CCD image sensor.

[0032] As shown in FIG. 3, the support roller 53 guides the rotation of the can lid L in the can lid temporary retention section 22, and in this embodiment, is configured as a driven roller that is rotatable about a vertical axis.

[0033] As shown in Figures 1 and 2, the inspection machine 60 is installed downstream of the rolling direction detection unit 50 and detects the orientation of the rolling direction of the can lid relative to the conveying direction. It is equipped with a light irradiation unit that irradiates light such as laser light obliquely from above onto a part of the can lid L (in this embodiment, a part of the center panel portion L4) transported by the conveyor 30, and a camera such as a CCD camera having an imaging element that images an area including the part illuminated by the light irradiated by the light irradiation unit. The inspection machine 60 detects the orientation of the rolling direction of the can lid L relative to the conveying direction of the can lid L based on image information showing the intensity distribution of the reflected light imaged by the camera (via a diffuser plate or the like arranged between the can lid L and the imaging element). In this embodiment, the inspection object of the can lid L (i.e., the portion onto which the light irradiated by the light irradiation unit described above is applied) for detecting the orientation of the rolling direction by the inspection machine 60 is the center panel portion L4, but other portions may also be inspected. As for the specific embodiment of the inspection machine 60, any type may be used as long as it is equipped with the above-mentioned light irradiation unit and detection elements such as the above-mentioned imaging element and light receiving element, and is capable of detecting the rolling direction of the can lid L based on the intensity distribution of the detected reflected light.

[0034] The control unit (not shown) is composed of a personal computer, a PLC (programmable logic controller), etc., and is connected to each part of the can end manufacturing apparatus 10 to control the operation of each part of the can end manufacturing apparatus 10 and perform various arithmetic processing. [Can lid manufacturing method]

[0035] Next, a can lid manufacturing method using the can lid manufacturing apparatus 10 of this embodiment will be described below.

[0036] First, the lowest one of the can lids L stored in the can lid storage section 21 is sent to the can lid temporary retention section 22 by the upper-side sending section 23a.

[0037] Next, in the can lid temporary retention section 22, the rolling direction of the can lid L is detected by the rolling direction detection unit 50 and a control unit (not shown), and the rolling direction of the can lid L is adjusted. Specifically, first, in the can lid temporary retention section 22, the can lid L is rotated by the rotation drive unit 51, and light is irradiated from the light emitting unit 52a at a predetermined angle Θ toward the irradiated surface of the can lid L (in this embodiment, the chuck wall portion L2) as shown in Figure 3 (b), and the reflected light reflected by the irradiated surface of the can lid L is received by the light receiving unit 52b, thereby detecting the light intensity of the reflected light. Here, when the can lid L is irradiated with irradiation light at a predetermined angle Θ, the reflected light is diffused depending on the state of the irradiated surface of the can lid L, and the light-receiving unit 52b receives only a part of the reflected light. The amount of light received by the light-receiving unit 52b changes continuously with the rotation of the can lid L due to the change in the state of the irradiated surface of the can lid L (the direction of the rolling marks L5 on the irradiated surface) with the rotation of the can lid L. Specifically, as can be seen from the graph in Fig. 7 and Fig. 6(b), the amount of light received by the light-receiving unit 52b changes continuously so that peaks P1, P2, and P3 of the intensity of the reflected light occur every half rotation (180° rotation) of the can lid L. As shown in FIG. 6(b), the intensity of the reflected light reaches a peak when the irradiated light is applied to points P1, P2, and P3 perpendicular to the rolling direction (the direction in which the rolling grain L5 extends). Here, P1 to P3 shown in FIG. 6(b) correspond to P1 to P3 shown in FIG. 7; that is, the light intensity when irradiating light is applied to the point P1 (or P2, P3) shown in FIG. 6(b) is represented by the symbol P1 (or P2, P3) in FIG. 7. Then, based on the continuous change information of the intensity of the reflected light read by the light receiving unit 52b (the change information shown in Figure 7), the rolling direction of the can lid L (the direction in which the rolling marks L5 extend) is detected by a control unit (not shown).

[0038] In order to ensure sufficient intensity of the reflected light received by the light-receiving unit 52b, it is preferable to install the light-emitting unit 52a with respect to the irradiated surface of the can lid L so that the incident angle Θ of the optical axis of the irradiated light with respect to the irradiated surface of the can lid L (i.e., the angle Θ with respect to a perpendicular line perpendicular to the irradiated surface of the can lid L as shown in Figure 3(b)) is 5 degrees or more and 15 degrees or less, and the distance between the irradiated surface of the can lid L and the light-receiving unit 52b (its light-receiving element) may be set arbitrarily depending on the embodiment, for example, to 20 mm to 900 mm.

[0039] Next, rolling direction information of the can lid L obtained by a control unit (not shown) is fed back to a rotational drive unit 51 functioning as a rotational position adjustment unit 51, and the rotational drive unit (rotational position adjustment unit) 51 adjusts the rotational position of the can lid L by positioning and stopping (stopping rotation) the can lid L at an appropriate rotational position. In this embodiment, as shown in FIG. 1, the rotational position of the can lid L is adjusted so that the rolling direction of the can lid L is perpendicular to the conveying direction of the can lid L by the conveying conveyor 30. However, the adjustment manner of the rotational position of the can lid L may be any, such as adjusting the rolling direction of the can lid L so that it is along the conveying direction. Further, the rotation drive unit (rotational position adjustment unit) 51 is configured to adjust the rotational position of the can lid L to a predetermined rotational position with an accuracy of within ±10° based on the rolling direction information.

[0040] Next, the can lids L whose rotational positions have been adjusted in the can lid temporary retention section 22 are sent out onto the transfer conveyor 30 by the lower-side sending section 23b. At this time, the can lids L sent downward are maintained in their rotational position by the rotational position maintaining unit 24 (that is, in this embodiment, a state in which the rolling direction is perpendicular to the conveying direction of the can lids L). In addition, in this embodiment, since the upper side feed section 23a and the lower side feed section 23b are formed on the same transfer rotor 23, at the timing when the can lids L are fed downward by the lower side feed section 23b, the lowest can lid L stored in the can lid storage section 21 is fed out by the upper side feed section 23a and sent to the can lid temporary retention section 22.

[0041] In the above, it was explained that after the rotational position of the can lid L is adjusted by the rotational drive unit (rotational position adjustment unit) 51 in the can lid temporary storage unit 22, the can lid L is sent out toward the conveying conveyor 30 while maintaining the rotational position of the can lid L by the rotational position maintenance unit 24. However, the manner in which the rotational position of the can lid L is adjusted by the rotational drive unit (rotational position adjustment unit) 51, etc. is not limited to the above, and at least in the can lid temporary storage unit 22, adjustment of the rotational position can be started after the rolling direction of the can lid L is detected by the rolling direction detection unit 50, and adjustment of the rotational position can be completed in time with the moment when the can lid L is sent out (cut out) by the lower side feed unit 23b. That is, as in the modified example shown in Fig. 5, the rotational position of the can lid L may be adjusted by bringing the rotational drive unit (rotational position adjustment unit) 51 into contact with the can lid L from the time when the can lid L is located in the can lid temporary retention unit 22 until the moment when the can lid L is fed (cut out) by the lower-side feed unit 23b, without providing the rotational position maintaining unit 24. In this case, from the viewpoint of suppressing damage to the contact portion (made of an elastic body) of the rotational drive unit (rotational position adjustment unit) 51 that contacts the can lid L, in the region (time period) in which the lower-side feed unit 23b feeds the can lid L downward, it is preferable to set the direction in which the rotational drive unit (rotational position adjustment unit) 51 rotates the can lid L to the same direction as the direction in which the lower-side feed unit 23b rotates the can lid L, and to set the speed at which the rotational drive unit (rotational position adjustment unit) 51 rotates the can lid L to be as similar as possible to the speed at which the can lid L is rotated by the lower-side feed unit 23b.

[0042] Next, the can lids L sent onto the conveying conveyor 30 are transported downstream by the conveying conveyor 30, and as shown in Figures 1 and 2, the orientation of the rolling direction of the can lids relative to the conveying direction is inspected by an inspection machine 60 installed midway along the conveying path. Here, when the inspection machine 60 detects a can lid L whose rolling direction is not correctly oriented relative to the conveying direction, the can lid L is rejected from the conveying path of the conveying conveyor 30 by a rejection machine (not shown) upstream or downstream (downstream in this embodiment) of the can lid processing machine 40.

[0043] Next, the can lids L are sent by the transport conveyor 30 to the can lid processing machine 40, which performs various processes on the can lids L, such as scoring, riveting, and forming the outer circumferential step portion L6.

[0044] Finally, the can lids L processed by the can lid processing machine 40 are sent to a process downstream of the can lid processing machine 40 by the transfer conveyor 30.

[0045] The can lid manufacturing apparatus 10 of this embodiment obtained in this manner is equipped with a rolling direction detection unit 50 and a control unit (not shown), and the control unit (not shown) is configured to detect the rolling direction of the can lid L based on information on changes in the light intensity of the reflected light reflected by the rotating can lid L obtained by the rolling direction detection unit 50. This makes it possible to detect the rolling direction of the can lid L without marking the can lid L with printing or a sticker, etc., and adjust the rotational position (direction of the rolling direction) of the can lid L based on the rolling direction information. Various processes such as score processing and processing for forming the outer stepped portion L6 can be performed on the can lid L in a state where the rotational position has been adjusted, thereby improving the quality of the can lid L.

[0046] In other words, if a score (not shown) is formed when there is variation in the rotational position (rolling direction) of the can lid L, variation will occur in the force required to open the can lid L (break the score).However, in this embodiment, it is possible to perform score processing, etc. on the can lid L in a state where the rotational position has been adjusted, so that the quality of the can lid L in terms of the opening force, etc. of the can lid L can be improved.

[0047] In addition, in this embodiment, the can lid L in a state in which the rotational position has been adjusted is processed to form a plate material deformed portion (in this embodiment, the outer peripheral step portion L6) by deforming the plate material of the center panel portion L4 in the thickness direction. Specifically, as shown in Figure 6(c), a virtual line X passing through a narrow width portion L4a (if the narrow width portion L4a has a width in the can lid circumferential direction, the center of the narrow width portion L4a in the can lid circumferential direction) described later and the center of the center panel portion L4 is formed so that it is parallel to or approximately parallel to the rolling direction (specifically, within ±10°), thereby improving the pressure resistance of the can lid L. That is, in the can lid L of this embodiment, the vicinity of the narrow width portion L4a is a region where the pressure resistance is lower (than other regions) due to the formation of the plate material deformation portion (in this embodiment, the outer peripheral step portion L6), and the portion Y shown in Figure 6(c) is a region where the pressure resistance is lower (than other regions) due to the rolling direction. However, in the can lid L of this embodiment, the portion (near the narrow width portion L4a) where the pressure resistance is lower due to the formation of the plate material deformation portion (in this embodiment, the outer peripheral step portion L6) and the portion Y where the pressure resistance is lower due to the rolling direction are not overlapped, so that the decrease in the pressure resistance of the can lid L can be suppressed (the pressure resistance of the can lid L can be improved). Here, the narrow width portion L4a mentioned above refers to the portion between at least one plate material deformation portion (in this embodiment, the outer peripheral step portion L6) and the outer edge of the center panel portion L4, as shown in Figure 6(c), where the distance between the plate material deformation portion (in this embodiment, the outer peripheral step portion L6) and the outer edge of the center panel portion L4 is the narrowest. In the above, the plate deformation portion is described as being the outer peripheral step portion L6, but the plate deformation portion is not limited to the outer peripheral step portion L6, but refers to a portion where the plate material of center panel portion L4 is deformed in the thickness direction, such as a portion where the plate material of center panel portion L4 is recessed downward or upward in the thickness direction as shown in Figure 6(d), like a so-called "finger grip embossment" or "bead." When multiple plate deformation portions are formed in the center panel portion L4, the narrow width portion L4a is the portion between each plate deformation portion and the outer edge of the center panel portion L4 where the distance between the plate deformation portion and the outer edge of the center panel portion L4 is narrowest.

[0048] The can lid supplying machine 20 also has a can lid storage section 21, a can lid temporary storage section 22 formed below the can lid storage section 21 and storing one can lid L, an upper side feed section 23a that sends the can lids L stored in the can lid storage section 21 to the can lid temporary storage section 22, and a lower side feed section 23b that sends the can lids L stored in the can lid temporary storage section 22 toward the conveying conveyor 30, and a rolling direction detection unit 50 is installed so as to perform rotational drive and detection of reflected light for the can lids L stored in the can lid temporary storage section 22. This allows the can lid manufacturing equipment 10 to have a complex configuration by utilizing the can lid temporary storage area 22 formed below the can lid storage area 21 of the can lid supplying machine 20 as a place to detect the rolling direction of the can lid L and perform rotational positioning (adjustment of the rotational position).

[0049] In addition, the transfer rotor 23 integrally has an upper side feed section 23a which feeds the can lids L stored in the can lid storage section 21 to the can lid temporary retention section 22 as the transfer rotor 23 rotates, and a lower side feed section 23b which feeds the can lids L retained in the can lid temporary retention section 22 toward the conveying conveyor 30 as the transfer rotor 23 rotates. As a result, by rotating the transfer rotor 23, it is possible to both move the can lids L from the can lid storage section 21 to the can lid temporary retention section 22, and move the can lids L from the can lid temporary retention section 22 to the conveying conveyor 30, thereby avoiding a complex device configuration.

[0050] In addition, since the can lid temporary retention section 22 is composed of an outer peripheral recess 23c formed by recessing the outer peripheral surface of the transfer rotor 23 in the area between the upper engagement section 23a and the lower engagement section 23b, it is possible to avoid the device configuration becoming complicated.

[0051] Although an embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various design modifications can be made without departing from the present invention described in the claims, such as configuring a can end manufacturing apparatus 10 or a can end manufacturing method by arbitrarily combining each configuration of the above or below embodiments and modified examples.

[0052] For example, in the above-described embodiment, the can lid L is described as having a chuck wall portion L2 and a center panel portion L4, but the specific form of the can lid L is not limited to the above-described embodiment and may be any. [Explanation of symbols]

[0053] 10...Can lid manufacturing equipment 20 · · Can lid feeding machine 21 Can lid storage section 22 Can lid temporary retention section 23 Transfer rotor 23a: Upper engagement portion (upper feed portion) 23b Lower engagement portion (lower feed portion) 23c: Outer circumferential recess 24 Rotational position maintaining section 25 ··· Guide pole 30 ..... Transport conveyor 40 ... Can lid processing machine 50 ··· Rolling direction detection unit 51 Rotation drive unit (rotation position adjustment unit) 52 Reflected light detection section 52a Light emitting part 52b: Light receiving section 53 Support roller 60 ··· Inspection machine L...Can lid L1: Curled part on outer periphery L2: Chuck wall part L3: Panel wall section L4 Center panel section L4a... Narrow part L5: Rolling marks L6: Step on outer periphery (deformed part of plate material)

Claims

1. A can end manufacturing apparatus for manufacturing can ends, The rolling direction detection unit includes a rotation drive unit for rotating the can lids and a reflected light detection unit, a control unit, and a can lid supplying device for supplying the can lids onto a transport conveyor, The reflected light detection unit has a light emitting unit that irradiates irradiation light onto the can lid and a light receiving unit that receives reflected light of the irradiation light reflected by the can lid, The control unit is configured to detect a rolling direction of the can lid based on information on a change in light intensity of the reflected light reflected by the rotating can lid, the information being obtained by the rolling direction detection unit; The can lid supplying machine includes a can lid storage section for storing a plurality of can lids in a stacked state, a can lid temporary retention section formed below the can lid storage section for retaining one can lid, an upper side feed section for feeding the can lids stored in the can lid storage section to the can lid temporary retention section, and a lower side feed section for feeding the can lids retained in the can lid temporary retention section toward the transfer conveyor, The can end manufacturing apparatus is characterized in that the rolling direction detection unit is installed so as to detect reflected light from the can ends retained in the can end temporary retention section.

2. 2. The can end manufacturing apparatus according to claim 1, wherein the rolling direction detection unit further comprises a rotational position adjustment unit that adjusts a rotational position of the can end based on the rolling direction information of the can end obtained by the control unit.

3. 3. The can end manufacturing apparatus according to claim 2, wherein the rotation drive unit and the rotation position adjustment unit are configured from the same equipment that rotates the can ends.

4. The can lid supplying machine includes a transfer rotor that can rotate around a vertical axis, The transfer rotor has an upper engaging portion that can engage with the can lid and a lower engaging portion that is formed below the upper engaging portion and can engage with the can lid on its outer circumferential surface, the upper engaging portion functions as the upper feeding portion that feeds the can lids stored in the can lid storage portion to the can lid temporary retention portion in accordance with the rotation of the transfer rotor, The can end manufacturing apparatus according to claim 1, characterized in that the lower engagement portion functions as the lower feed portion which feeds the can ends retained in the can end temporary retention portion toward the conveying conveyor as the transfer rotating body rotates.

5. 5. The can end manufacturing apparatus according to claim 4, wherein the can end temporary retention portion is constituted by an outer peripheral recess provided in the outer peripheral surface of the transfer rotor in the region between the upper engagement portion and the lower engagement portion.

6. The rolling direction detection unit further includes a rotational position adjustment unit that adjusts a rotational position of the can lid based on the rolling direction information of the can lid obtained by the control unit, 2. The can end manufacturing apparatus according to claim 1, wherein the rotational position adjustment unit is configured to start adjusting the rotational position of the can ends at least in the can end temporary retention unit.

7. 7. The can lid manufacturing method according to claim 6, wherein the rotational position adjusting unit is configured to adjust the rotational position of the can lid to a predetermined rotational position with an accuracy of within ±10°.

8. 2. The can end manufacturing apparatus according to claim 1, wherein the light emitting portion of the reflected light detecting portion is disposed so as to irradiate light onto the chuck wall portion of the can end from the outer periphery side.

9. 2. The can end manufacturing apparatus according to claim 1, further comprising an inspection machine disposed downstream of the rolling direction detection unit for detecting an orientation of the rolling direction of the can ends relative to a conveying direction of the can ends.

10. A can lid manufacturing method for manufacturing a can lid, comprising the steps of: The rolling direction detection unit includes a rotation drive unit for rotating the can lids and a reflected light detection unit, a control unit, and a can lid supplying device for supplying the can lids onto a transport conveyor, The reflected light detection unit has a light emitting unit that irradiates irradiation light onto the can lid and a light receiving unit that receives reflected light of the irradiation light reflected by the can lid, The control unit detects the rolling direction of the can lid based on information on a change in light intensity of the reflected light from the rotating can lid, the information being obtained by the rolling direction detection unit; The can lid supplying machine includes a can lid storage section for storing a plurality of can lids in a stacked state, a can lid temporary retention section formed below the can lid storage section for retaining one can lid, an upper side feed section for feeding the can lids stored in the can lid storage section to the can lid temporary retention section, and a lower side feed section for feeding the can lids retained in the can lid temporary retention section toward the transfer conveyor, The can end manufacturing method, wherein the rolling direction detection unit detects reflected light from the can ends retained in the can end temporary retention section.

11. A can lid manufactured by the can lid manufacturing method according to claim 10.

12. The can lid has a center panel portion, At least one plate material deformation portion is formed in the center panel portion by deforming a plate material in a thickness direction, the center panel portion has a narrow portion, which is a portion between at least one of the plate material deformation portions and an outer edge of the center panel portion, where the distance between the plate material deformation portion and the outer edge of the center panel portion is narrowest, The can lid according to claim 11, wherein the can lid is formed such that an imaginary line passing through the narrow width portion and a center of the center panel portion is parallel or substantially parallel to the rolling direction.

13. A can container containing a content, comprising the can lid according to claim 11, and a can body filled with a content and seamed around the can lid.

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