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

Abstract

[Problem] To provide a can lid manufacturing device, a can lid manufacturing method, a can lid, and a can container containing contents, in which can lid openability and pressure resistance are improved through a simple configuration. [Solution] A can lid manufacturing device 10 for manufacturing a can lid L, wherein: the can lid manufacturing device 10 comprises a control unit and a rolling direction detection unit 50 having a reflection light detection part 52 and a rotation drive part 51 for rotating the can lid L; the reflection light detection part 52 has a light emission part 52a and a light reception part 52b; and the control unit is configured to detect the rolling direction of the can lid L on the basis of information representing a change in light intensity of reflected light reflected by the rotating can lid L, the information being obtained by the rolling direction detection unit 50.

Description

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

[0001] The present invention relates to a can lid manufacturing device, a can lid manufacturing method, a can lid, and a can container containing a content.

[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 that make up such can containers are formed from rolled metal plates formed by rolling processing.

[0003] Patent No. 4239039

[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 on the rolled metal sheet extend) and the direction in which scores, etc., are formed on the can lid affects the openability of the can lid (i.e., the force required to break the scores) 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 that have a simple configuration and improve the openability and pressure resistance of can lids.

[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, wherein the reflected light detection unit has an emitting unit that irradiates light onto the can lids and a light receiving unit that receives reflected light from the irradiated light reflected by the can lids, and 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 that manufactures can lids, and includes a rolling direction detection unit having a rotation drive unit that rotates the can lids and a reflected light detector, and a control unit. The reflected light detector has a light emitter that irradiates the can lids with light and a light receiver that receives reflected light reflected by the can lids. The control unit detects 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. 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 lids based on information on the rolling direction of the can lids obtained by the control unit. In any of the above can lid manufacturing apparatus (or can lid manufacturing method), the rotation drive unit and the rotational position adjustment unit may be composed of the same equipment that rotates the can lids. Any of the above can lid manufacturing devices (or can lid manufacturing methods) may further include a can lid supply machine that supplies can lids onto the conveying conveyor, and the can lid supply machine may have 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 a single can lid, an upper feed section that sends the can lids stored in the can lid storage section to the can lid temporary storage section, and a lower feed section that sends the can lids that have 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 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 supply device may include a transfer rotor rotatable about a vertical axis, the transfer rotor having an upper engagement portion engageable with the can lid and a lower engagement portion formed below the upper engagement portion and engageable with the can lid on its outer surface, the upper engagement portion functioning as the upper feed portion to feed 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 functioning as the lower feed portion to feed can lids retained in the can lid temporary retention portion toward the conveyor as the transfer rotor rotates.In any of the above can lid manufacturing devices (or can lid manufacturing methods), the can lid temporary retention portion may be composed of an outer peripheral recess recessed in the outer peripheral surface of the transfer rotor in a region between the upper engagement portion and the lower engagement portion. In any of the above 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 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 area. In any of the above can lid manufacturing apparatuses (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 lid manufacturing apparatuses (or can lid manufacturing methods), the light-emitting unit of the reflected light detection unit may be installed to irradiate light onto a chuck wall portion of the can lid from the outer periphery. In any of the above can lid manufacturing apparatuses (or can lid manufacturing methods), the above can lid manufacturing apparatuses (or can lid manufacturing methods) may further include an inspection machine installed downstream of the rolling direction detection unit that detects the orientation of the rolling direction of the can lid relative to the conveying direction of the can lid. The can lid of the present invention solves the above problem by being manufactured by any of the above can lid manufacturing apparatuses (or can lid manufacturing methods).In the can lid of the present invention, the can lid may have a center panel portion, and at least one sheet material deformation portion is formed in the center panel portion by deforming a sheet material in a thickness direction, and the center panel portion may have a narrow width portion between the at least one sheet material deformation portion and an 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 narrowest, and the can lid may be formed so that an imaginary line passing through the narrow width portion and a center of the center panel portion is parallel or approximately parallel to the rolling direction. The can container containing content of the present invention solves the above problem by comprising the can lid and a can body portion filled with content and around which the can lid is seamed.

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

[0008] An explanatory diagram showing a can lid manufacturing device according to one embodiment of the present invention. An explanatory diagram showing a can lid manufacturing device according to one embodiment of the present invention as seen from the side. An explanatory diagram showing the peripheral configuration of a can lid temporary retention section. An explanatory diagram showing the peripheral configuration of a can lid temporary retention section as seen from the side. An explanatory diagram showing a modified example. An explanatory diagram showing an example of a can lid. A graph showing changes in light intensity of detected reflected light.

[0009] A can lid manufacturing apparatus 10 and a can lid 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 of the portions L1, L2, and L3 of the can lid L is formed in an annular (circular ring) shape.

[0012] 1 and 6(c), the center panel portion L4 is formed with groove-shaped scores (not shown) that function as weakened portions when the can lid L is opened, rivets (not shown) for securing tabs to the center panel portion L4, and an outer peripheral step L6 formed to surround the scores (not shown). As shown in Fig. 6(c), the outer peripheral step L6 is a portion formed by deforming the sheet material of the center panel portion L4 in the thickness direction so that the inner peripheral portion (recess panel) is one step lower than the outer peripheral portion. Figs. 6(a) and 6(b) show the can lid L without the scores (not shown), rivets (not shown), or outer peripheral step L6, while Fig. 6(c) shows the can lid L without the scores (not shown), rivets (not shown), or outer peripheral step L6.

[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 directed is in a state in which the metallic gloss surface of the rolled metal plate is exposed (or is coated with a coating such as transparent paint, ink, or transparent resin that does not block light) so as to reflect at least a portion of the irradiated light (at least at the time of performing the process of detecting the rolling direction of the can lid L using the irradiated light).

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

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

[0016] First, the can lid manufacturing device 10 manufactures can lids L, and as shown in Figures 1 and 2, is equipped with a can lid supply machine 20 that supplies can lids L (in the process of being manufactured) one by one onto a conveyor 30, the conveyor 30 that conveys the can lids L supplied from the can lid supply machine 20, a can lid processing machine 40 that is installed downstream of the conveyor 30 and performs various processes such as scoring on the can lids L, a rolling direction detection unit 50 that detects the rolling direction of the can lids 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 lids relative to the conveying direction of the can lids, 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 can lid temporary storage section 22 formed below the can lid storage section 21, a plurality of transfer rotors 23 that feed 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 that guide 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 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 Fig. 4, the can lid temporary retention section 22 is composed of an outer peripheral recess 23c recessed into the outer peripheral surface of the transfer rotor 23 in the region between (the portion where) an upper side engagement section 23a (described later) and (the portion where) a lower side engagement section 23b (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 feeds (moves) the can lids L downward as it rotates. As shown in Figure 4, the transfer rotor 23 has an upper engaging portion 23a that can engage with the can lid L (its outer peripheral curled portion L1), and a lower engaging portion 23b that is formed below the upper engaging portion 23a with a gap therebelow and is also able to engage with the can lid L (its outer peripheral curled portion L1). The upper engaging portion 23a functions as an upper feeding portion 23a that feeds the lowest can lid L among the can lids stored in the can lid storage section 21 downward toward the can lid temporary retention section 22 as the transfer rotor 23 rotates. In addition, the lower engagement portion 23b functions as a lower feeding portion 23b that feeds a single can lid L that has accumulated in the can lid temporary accumulation portion 22 downward toward the transport conveyor 30 as the transfer rotor 23 rotates.

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

[0022] In addition, in this embodiment, the upper side engagement portion 23a and the lower side engagement portion 23b are composed of 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 can be any form that can send the can lid L downward as the transfer rotor 23 rotates.

[0023] The rotational position maintaining unit 24 maintains the rotational position of the can lid L when the can lid L is sent from the can lid temporary storage unit 22 onto the transport conveyor 30, i.e., prevents the can lid L from rotating. In this embodiment, the rotational position maintaining unit 24 is made of an elastic material 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] As shown in Figures 1 and 2, the transfer conveyor 30 transfers the can lids L supplied from the can lid supply device 20. In this embodiment, the transfer conveyor 30 is configured using a conveyor belt, but the specific form of the transfer conveyor 30 may be any form that can transfer the can lids L, such as a roller conveyor or a vacuum conveyor. In this embodiment, the transfer conveyor 30 is configured to pitch-feed (intermittently move) the can lids L, but the specific form of the transfer conveyor 30 may be any form that continuously feeds the can lids L, for example.

[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 transport 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 area 22 around a vertical axis. In this embodiment, the rotation drive unit 51 is configured as a drive roller driven by a drive source such as a servo motor and capable of rotating (spinning) around a vertical axis. At least the portion of the rotation drive unit 51 that contacts the can lids L is made of an elastic material such as urethane. As will be described in detail later, the rotation drive unit 51 functions as a unit that rotates the can lids L when detecting the rolling direction of the can lids L. It also functions as a rotation position adjustment unit 51 that adjusts the rotation position of the can lids L by positioning and stopping the can lids L at an appropriate rotation position based on rolling direction information of the can lids 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 lids L. In addition, the specific aspects of the rotation drive unit 51 and the rotation position adjustment unit 51 are 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 separate equipment.

[0029] As shown in Figure 3, the reflected light detection unit 52 has an emitter 52a that emits 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 light.

[0030] 3(b), the light-emitting unit 52a is installed so as to irradiate light from the outer periphery of the chuck wall portion L2 (which is inclined so as to increase in diameter as it goes upward) of the can lid L. The part of the can lid L that is irradiated with light from the light-emitting unit 52a is not limited to the chuck wall portion L2, and may be, for example, the outer periphery curl portion L1.

[0031] 3(b), the light-emitting unit 52a is disposed above the light-receiving unit 52b, but the relative positions of the light-emitting unit 52a and the light-receiving unit 52b are not limited to this, and any arrangement 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. The light-receiving unit 52b may be any arrangement that receives the light reflected by the can lid L and detects the intensity of the reflected light, such as a light-receiving element such as a laser sensor or 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 can rotate around a vertical axis.

[0033] 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 lids relative to the conveyance direction. It includes a light irradiator that irradiates a portion of the can lids L (in this embodiment, a portion of the center panel portion L4) conveyed by the conveyor 30 with light such as a laser beam obliquely from above, and a camera such as a CCD camera with an image sensor that captures an image of the area including the portion illuminated by the light irradiated by the light irradiator. The inspection machine 60 detects the orientation of the rolling direction of the can lids L relative to the conveyance direction of the can lids L based on image information indicating the intensity distribution of the reflected light captured by the camera (via a diffuser or the like disposed between the can lids L and the image sensor). In this embodiment, the inspection target of the can lids L (i.e., the portion irradiated with light from the light irradiator) 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 form 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), or the like, and is connected to each part of the can lid manufacturing apparatus 10 to control the operation of each part of the can lid 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 accumulation 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 and adjusted by the rolling direction detection unit 50 and a control unit (not shown). Specifically, first, in the can lid temporary retention section 22, while the can lid L is rotated by the rotation drive unit 51, as shown in FIG. 3( b), the light-emitting unit 52a irradiates the irradiated surface of the can lid L (the chuck wall portion L2 in this embodiment) with light at a predetermined angle Θ, and the light-receiving unit 52b receives the reflected light reflected by the irradiated surface of the can lid L, thereby detecting the light intensity of the reflected light. Here, when the irradiated light is irradiated onto the can lid L at the 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 portion 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 changes in the state of the irradiated surface of the can lid L (the orientation of the roll marks L5 on the irradiated surface) as the can lid L rotates. 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 appear every half rotation (180° rotation) of the can lid L. As shown in Fig. 6(b), the intensity of the reflected light reaches its peaks when the irradiated light hits points P1, P2, and P3 perpendicular to the rolling direction (the direction in which the roll marks L5 extend). Here, P1 to P3 shown in Fig. 6(b) correspond to P1 to P3 shown in Fig. 7, that is, the light intensity when irradiated with light is directed at 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 (change information shown in Fig. 7) of the intensity of the reflected light read by the light receiving unit 52b, the rolling direction of the can lid L (the direction in which the rolling mark L5 extends) 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 relative to the irradiated surface of the can lid L so that the incident angle Θ of the optical axis of the irradiated light relative 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 (light-receiving element) may be set arbitrarily depending on the embodiment, for example, from 20 mm to 900 mm.

[0039] Next, the rolling direction information of the can lids L obtained by a control unit (not shown) is fed back to the rotation drive unit 51 functioning as the rotation position adjuster 51, and the rotation drive unit (rotation position adjuster) 51 adjusts the rotation position of the can lids L by positioning and stopping (stopping rotation) the can lids L at an appropriate rotation position. In this embodiment, as shown in FIG. 1 , the rotation position of the can lids L is adjusted so that the rolling direction of the can lids L is perpendicular to the conveying direction of the can lids L by the conveyor 30. However, any manner of adjusting the rotation position of the can lids L may be used, such as adjusting so that the rolling direction of the can lids L is along the conveying direction. Furthermore, the rotation drive unit (rotation position adjuster) 51 is configured to adjust the rotation position of the can lids L to a predetermined rotation 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 by the lower feed section 23b toward the transfer conveyor 30. At this time, the rotational position of the can lids L sent downward is maintained by the rotational position maintaining section 24 (i.e., in this embodiment, a state in which the rolling direction is perpendicular to the conveying direction of the can lids L). In this embodiment, since the upper feed section 23a and the lower feed section 23b are formed on the same transfer rotor 23, at the same time that the can lids L are sent downward by the lower feed section 23b, the lowest can lid L stored in the can lid storage section 21 is sent out by the upper feed section 23a and sent to the can lid temporary retention section 22.

[0041] In the above description, it has been 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 retention unit 22, the rotational position of the can lid L is maintained by the rotational position maintenance unit 24, and the can lid L is sent out toward the transfer conveyor 30. 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 and the like is not limited to the above. At least in the can lid temporary retention unit 22, it is sufficient to start adjusting the rotational position after the rolling direction of the can lid L is detected by the rolling direction detection unit 50, and the adjustment of the rotational position may be completed in time with the moment when the can lid L is sent out (cut out) by the lower feed unit 23b. 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 the can lid L is positioned in the can lid temporary retention unit 22 until the moment the can lid L is fed (cut out) by the lower 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 feed unit 23b feeds the can lid L downward, it is preferable to make the direction in which the rotational drive unit (rotational position adjustment unit) 51 rotates the can lid L the same as the direction in which the lower 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 and the speed at which the lower feed unit 23b rotates the can lid L to be as similar as possible.

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

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

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

[0045] The can lid manufacturing apparatus 10 of this embodiment obtained in this manner includes 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 reflected light reflected by the rotating can lid L, which information is obtained by the rolling direction detection unit 50. This makes it possible to detect the rolling direction of the can lid L without attaching a mark such as a print or a sticker to the can lid L, adjust the rotational position (orientation of the rolling direction) of the can lid L based on the rolling direction information, and perform various processes such as scoring and forming an outer peripheral step portion L6 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, there will be variation 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 can lids L with their rotational position adjusted, so the quality of the can lids L can be improved in terms of the opening force, etc.

[0047] Furthermore, in this embodiment, the can lid L, whose rotational position has been adjusted, is processed to form a plate material deformation portion (in this embodiment, an 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), by processing such as forming a plate material deformation portion (in this embodiment, an outer peripheral step portion L6) so that an imaginary line X passing through a narrow width portion L4a (described later) (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) and the center of the center panel portion L4 is parallel or approximately parallel (specifically, within ±10°) to the rolling direction, the pressure resistance of the can lid L can be improved. 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 sheet material deformation portion (in this embodiment, the outer peripheral step portion L6), and the portion Y shown in FIG. 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 region where the pressure resistance is lower due to the formation of the sheet material deformation portion (in this embodiment, the outer peripheral step portion L6) (near the narrow width portion L4a) and the portion Y where the pressure resistance is lower due to the rolling direction are not overlapped, thereby suppressing a decrease in the pressure resistance of the can lid L (improving the pressure resistance of the can lid L). Here, the narrow width portion L4a refers to the portion between at least one sheet 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 FIG. 6( c). In the above description, 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, and refers to a portion of the center panel portion L4 where the plate material is deformed in the thickness direction, such as a portion where the plate material of the center panel portion L4 is recessed downward or upward in the thickness direction, as shown in Fig. 6(d), such as a so-called "finger-hold 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 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 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 feed section 23b that sends the can lids L stored in the can lid storage section 21 to the can lid temporary storage section 22 toward the transfer conveyor 30, and the rolling direction detection unit 50 is installed to rotate the can lids L stored in the can lid temporary storage section 22 and detect reflected light. Thus, by using the can lid temporary storage section 22 formed below the can lid storage section 21 of the can lid supplying machine 20 as a place to detect the rolling direction of the can lids L and perform rotational positioning (adjustment of the rotational position), the can lid manufacturing apparatus 10 can be prevented from having a complex configuration.

[0049] Furthermore, the transfer rotor 23 integrally includes an upper feed section 23a that 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 feed section 23b that feeds the can lids L that have accumulated in the can lid temporary retention section 22 toward the transfer conveyor 30 as the transfer rotor 23 rotates. This makes it 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 transfer conveyor 30 by rotating the transfer rotor 23, thereby avoiding a complex device configuration.

[0050] In addition, since the can lid temporary storage 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, the device configuration can be prevented from becoming complicated.

[0051] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design modifications can be made without departing from the present invention as defined in the claims, such as by arbitrarily combining the configurations of the above or below embodiments and modified examples to form a can lid manufacturing apparatus 10 or a can lid manufacturing method.

[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.

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

Claims

1. A can lid manufacturing device for manufacturing can lids, comprising: a rolling direction detection unit having a rotation drive unit for rotating the can lids and a reflected light detection unit; and a control unit, wherein the reflected light detection unit has a light emitting unit for irradiating light onto the can lids and a light receiving unit for receiving reflected light of the irradiated light reflected by the can lids, and the control unit is configured to detect the rolling direction of the can lids based on information on changes in light intensity of the reflected light reflected by the rotating can lids, obtained by the rolling direction detection unit.

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

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 manufacturing apparatus as described in claim 1, further comprising a can lid supplying machine that supplies can lids onto the 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 retention section formed below the can lid storage section for retaining 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 retention section, and a lower side feed section that feeds the can lids retained in the can lid temporary retention section towards the conveyor, and the rolling direction detection unit is installed to detect reflected light from the can lids retained in the can lid temporary retention section.

5. The can lid supplying machine is equipped with a transfer rotor that can rotate around a vertical axis, and the transfer rotor has an upper engagement portion on its outer surface that can engage with the can lids and a lower engagement portion formed below the upper engagement portion and that can engage with the can lids, 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 retained in the can lid temporary retention portion toward the conveying conveyor as the transfer rotor rotates.

6. A can lid manufacturing apparatus as described in claim 5, characterized in that the can lid temporary retention portion is composed of an outer peripheral recess recessed into the outer peripheral surface of the transfer rotor in the area between the upper engagement portion and the lower engagement portion.

7. The can lid manufacturing apparatus described in claim 4, characterized in that the rolling direction detection unit further comprises 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, and the rotational position adjustment unit is configured to start adjusting the rotational position of the can lid at least in the can lid temporary retention area.

8. The can lid manufacturing method according to claim 7, characterized in that the rotational position adjustment unit is configured to adjust the rotational position of the can lid to a predetermined rotational position with an accuracy of within ±10°.

9. The can lid manufacturing apparatus according to claim 1, wherein the light emitting section of the reflected light detecting section is installed so as to irradiate light onto the chuck wall section of the can lid from the outer periphery side.

10. The can end manufacturing apparatus according to claim 1, further comprising an inspection device installed downstream of the rolling direction detection unit for detecting the orientation of the rolling direction of the can ends relative to the conveying direction of the can ends.

11. A can lid manufacturing method for manufacturing can lids, comprising: 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, wherein 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, and the control unit detects the rolling direction of the can lid based on information on changes in light intensity of the reflected light reflected by the rotating can lid, obtained by the rolling direction detection unit.

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

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

14. A can container containing contents, comprising the can lid according to claim 12, and a can body filled with contents and around which the can lid is seamed.

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