EP1157764A1

EP1157764A1 - A flanging machine for metallic containers

Info

Publication number: EP1157764A1
Application number: EP00830378A
Authority: EP
Inventors: Carlo Bisacchi
Original assignee: ASA Italia SpA
Current assignee: ASA Italia SpA
Priority date: 2000-05-26
Filing date: 2000-05-26
Publication date: 2001-11-28

Abstract

A machine (1) for flanging metallic containers (2) comprises at least a pair of flanging plugs (7a, 7b) mutually opposite and coaxial, located downstream of a station (4) for feeding the containers (2) and upstream of a station (5) for offloading the containers (2). The plugs (7a, 7b) are movable relatively and alternatively along their own common axis (70) from a distance at least corresponding to the height of a container (2) to a distance whereat the plugs (7a, 7b) are forcibly inserted into openings (20a, 20b) of the container (2) holding it firmly and causing its flanging. In this phase, a punching die (8), integral with an outer lateral surface (71) of at least one of the plugs (7a or 7b) of the pair, cooperates with a punch (9) to produce tactile warnings on the lateral walls (20) of the container (2). The plugs (7a, 7b) are also movable according to a second common motion component along a trajectory lying in a plane perpendicular to the common axis (70) of the plugs (7a, 7b). The punch (9) participates in the motion of the pair of plugs (7a, 7b), thrust on the punching die (8) by the interaction with at least an element fixed to the support structure 3, comprised in actuator means (10) for actuating the punch (9) and located in a predetermined point of the trajectory of the second motion component of the plugs 7a, 7b).

Description

The present invention relates to a flanging machine for metallic containers.
Usually, flanging machines are inserted in automated lines for the production of metallic containers to shape the edge of the lateral walls of the containers, thereby allowing for the subsequent stable and secure application of bottom and lid to the container.
The aforesaid production lines generally comprise, downstream of a conveyor of plate sheets, a sheet folding or shaping station which makes the lateral walls of the containers. A subsequent welding station joins the extreme edges of the sheets thus folded or shaped. The container thereby obtained, still lacking bottom and lid, is then inserted into the flanging machine which performs the flanging operation.
Commonly, flanging machines have an inlet or station for feeding the metallic containers to be flanged. A conveyor transports the containers between one or more pairs of coaxial plugs, which approach each other and penetrate into the container through the openings corresponding to bottom and lid. The plugs are then forcibly inserted into the container, holding it tightly and causing its flanging. Once the flanging operation is complete, the plugs withdraw and the flanged container is carried by the conveyor to an outlet or off-loading station.
During manufacturing, it is often necessary to provide metallic containers with tactile warnings, which allow sight impaired persons to acquire, simply by handling the container, information about the type and quality of the product contained therein. This is particularly important if the product is hazardous, toxic, harmful or inedible. These tactile warnings are generally located in an appropriate position on the lateral walls of the container.
Usually a continuously operating applying machines is added to the line in order to apply adhesives bearing the raised tactile warnings onto the container. This solution has the drawback that the adhesive is degradable and may become detached over time.
Downstream of the welding station, the use is known of branching stations of the manufacturing line which draw the container from the line, generate the tactile warning by punching and then reinsert the container on the line itself. Such branches have the drawback of complicating the line with a specific apparatus, leading to problems with the operating times as well as problems with the synchrony and logistical flow of production.
If the welding operation takes place by the seaming of the plate and subsequent hot gluing with adhesive, the prior art provides for the insertion on the seamer of a punching machine, which works in phase with the seamer and exploits the stopping of the plate in the seamer itself. This solution has the drawback that it cannot be applied on lines that comprise a seaming station with continuously operating electric welder, except by paying the price of introducing a forced stop and, thus, of slowing production down. Moreover, the insertion of an independent punching device, immediately upstream or immediately downstream of the electric welder, leads to synchrony problems between punching machine and line, causing consequent risks of damaging the electric welder as a result of the prolonged safety stop of the line, if the punching machine fails to stop and continues to strike.
The aim of the present invention is to overcome the aforesaid drawbacks, making available a flanging machine for metallic containers, which comprises a device for obtaining tactile warnings on the walls of the containers that acts by punching when the plugs tightly hold the container causing its flanging.
Another aim of the present invention is to make available a flanging machine for metallic containers in which the device for manufacturing tactile warnings is synchronised with the action of the flanging plugs without any need for complicated independent control systems.
These aims and others besides, which shall become more readily apparent in the course of the description that follows, are achieved, in accordance with the present invention, by a flanging machine for metallic containers as described in the accompanying claims.
The invention is described more in detail below, with the aid of the drawings, which represent an embodiment provided purely by way of non limiting example.

Figure 1 shows a schematic front view of a preferred embodiment of the invention, in which for the sake of greater clarity not all devices for the manufacture of tactile warnings associated to the flanging plugs are shown, and some parts are removed the better to highlight others;
Figure 1a shows a detail of Figure 1 with the punch located in its first rest position;
Figure 1b shows a detail of Figure 1, with the punch located in its second operative position;
Figure 2 is a schematic lateral view of a part of the device for the manufacture of tactile warnings comprised in the flanging machine of the present invention and associated to a flanging plug.
Figures 3 and 4 schematically show in detail some components of the device for manufacturing tactile warnings comprised in the flanging machine of the present invention, with some parts removed the better to identify others.

With reference to the figures, the reference number 1 indicates a flanging machine for metallic containers 2 of the kind comprising a support structure 3, merely sketched purely for illustrative purposes, a station 4 for feeding metallic containers 2 to be flanged, a station 5 for offloading the flanged metallic containers 2, also merely sketched purely for illustrative purposes, and means 6 for conveying the containers 2 from the feeding station 4 to the offloading station 5. The conveying means 6 are also shown in dashed lines in Figure 1 for purely illustrative purposes. When the metallic containers 2 are inside the flanging machine, they only have lateral walls 20 and openings 20a, 20b corresponding to bottom and lid. At least a pair of flanging plugs 7a, 7b, mutually opposite and coaxial, is located downstream of the feeding station 4 and upstream of the offloading station 5. The plugs 7a, 7b are movable, along their own common axis 70, according to a first relative motion component. This relative motion is alternated at least between a first configuration (shown in the upper part of Figure 1) in which the plugs 7a, 7b are separated by a distance at least corresponding to the height of a container 2 and in which the container 2 is coaxial with the plugs 7a, 7b, and a second configuration (shown in the lower part of Figure 1) in which the plugs 7a, 7b are forcibly inserted into the openings 20, 20b of the container 2 holding it tightly and causing its flanging. The flanging machine 1 also comprises a device for producing tactile warnings on the lateral walls 20 of the container 2, which comprises at least a punching die 8 and at least a punch 9. The punching die 8 bears the print of the tactile warning and it is integral with an external lateral surface 71 of at least one of the plugs 7a or 7b of the pair. As shown in Figure 2, the punch 9 has its head 90 counter-shaped relative to the punching die 8 and is movable between a first position distanced from the punching die 8, when the pair of plugs 7a, 7b is in the first configuration, and a second position of pressure on the punching die 8, when the pair of punches 7a, 7b is in the second configuration and the lateral walls 20 of the container are interposed between said die 8 and said punch 9 to obtain the tactile warning. The first position of the punch 9 is shown in the upper part of Figure 1, in Figure 1a and in Figure 2, whilst the second position is shown in the lower part of Figure 1 and in Figure 1b. Also provided are actuator means 10 for actuating the punch 9 between the first and the second position.
In this way, the plugs 7a, 7b, coaxial to the container 2, are inserted into the opening 20a, 20b of the container 2 itself and cause its flanging, whilst, as shown in the lower part of Figure 1 and in Figure 1b, the punch 9 is thrust by the actuator means 10 against the die 8 at the moment in which the container 2 is firmly held by the plugs 7a, 7b themselves to obtain the required tactile warning.
Advantageously, a head 73 of the plug 7a or 7b on whose outer lateral surface 71 is located the punching die 8 has, at least towards the punching die 8, a greater diameter than the diameter of the body of the plug 7a or 7b, to allow the insertion of the plug 7a or 7b into the opening 20a or 20b of the container 2 without sticking on the die 8 itself. This is useful when the punching die 8 is raised.
The plugs 7a, 7b are also movable according to a second common motion component along a trajectory lying in a plane perpendicular to the common axis 70 of the plugs 7a, 7b whilst the common axis 70 maintains its direction constant over time. This second common motion component is in phase with the motion of the containers 2 to be flanged determined by the conveyor means 6, so that the plugs 7a, 7b follow the motion of the containers 2 inside the flanging machine 1. The flanging machine 1 can thus also be obtained in an in-line configuration.
Advantageously, the second component of common motion of the plugs 7a, 7b is a revolution motion about an axis 11 parallel to the common axis 70 of the plugs 7a, 7b. In particular, in a preferred embodiment of the invention shown in Figure 1, the flanging machine 1 comprises a plurality of pair of plugs 7a, 7b distributed at the periphery of two coaxial drums 12a, 12b rotating in phase with each other. To each pair of plugs 7a, 7b is associated a punching die 8 and a corresponding punch 9. The containers 2 can thus be fed to and off-loaded from the flanging machine 1 by gravity. The conveyor means 6 can be constituted by elements rotating integrally with the drums 12a, 12b and present, in correspondence with the plugs 7a, 7b, shapes able to receive the containers 2 and to determine the revolution of such containers 2 about the axis 11 in phase with the corresponding plugs 7a, 7b. In this particular embodiment of the invention, the motions of the drums 12a, 12b, of the conveyor means 6 and of the plugs 7a, 7b can be synchronised easily and actuated by a single motorised drive.
In a preferred embodiment of the invention, the punch 9 also participates in the motion of the pair of plugs 7a, 7b. In this way, the manufacture of the tactile warning does not bring about any interruptions in the operation of the flanging machine 1 which can thus be inserted in a continuously operating line for the production of containers 2. In this case, the actuator means 10 for actuating the punch 9 comprise at least an element fixed to the support structure 3, located in a predetermined point of the trajectory of the second motion component of the plug 7a or 7b and interacting with the punch 9 when the punch 9 is in correspondence with said predetermined point, to cause its motion from the first to the second position. In this way, a single fixed element interacts, on each occasion, with each of the punches 9 corresponding to the plugs 7a or 7b at the moment in which the punches 9 are in correspondence with the fixed element itself due to the common motion of the plugs 7a, 7b of the containers 2 and of the punches 9.
Advantageously, the punch 9 is rigidly connected to a lever 13 and the fixed element of the actuator means 10 interacts with the lever 13. Said lever 13 itself is also subject to elastic means 16 contrasting the motion of the punch 9 from the first to the second position, to return the punch 9 to the first position once the interaction between the fixed element and the lever 13 ceases.
The fixed element can, for instance, comprise an oleo-dynamic cylinder able to press on the punch 9 as a result of a signal received from proximity sensors.
In a preferred embodiment of the invention shown in the figures, the lever 13 has its fulcrum 14 associated to a support 72 of the plug 7a or 7b on whose outer lateral surface 71 is located the punching die 8. The punch 9 is rigidly connected to a first extremity 13a of the lever 13, a second extremity 13b of the lever 13 being opposite to the first extremity 13a relative to the fulcrum 14 and destined to interact with the fixed element of the actuator means 10. In this case, advantageously, said fixed element is constituted by a cam 15 located in a predetermined position of the trajectory of the second component of motion of the plug 7a or 7b. The cam 15 is also fixed to the support structure 3 of the flange machine 1 and, as shown in Figure 3, shaped in such a way as to cause the motion of the punch 9 between the first and the second position. In particular, the cam 15 comprises a shaped element 50, possibly provided with a bulge 51 to determine an impulsive pressure of the punch 9 on the punching die 8 when necessary. The cam also comprises an element 52 for guiding the motion of the second extremity 13b of the lever 13. Figure 3 also schematically shows the motion of the second extremity 13b in the cam 15.
This solution allows an automatic synchronisation of all movements and the actuation of the motion of the punch 9 with no need for complicated detection and actuation systems. The flanging machine is thus able to manufacture the tactile warnings on the side walls 20 of the containers 2 with no modification in its intervention times on the production line.
Conveniently, the position of the cam 15 can be adjusted in space.
Advantageously, moreover, the lever 13 has, in correspondence with the second extremity 13b, rolling friction means 19 to favour its sliding on the cam 15. The position of the rolling friction means 19 relative to the lever 13 is adjustable, to allow to regulate the pressure of the punch 9 on the punching die 8 and also to adjust for any modifications in the positioning of the cam 15. In particular, in the embodiment of the invention shown in Figure 2, the rolling friction means 19 are constituted by a simple roller 21 pivoted on the second extremity 13b of the lever 13. The position of the axis 22 of rotation of the roller 21 relative to the lever 13 is adjustable by means of an eccentric system: in particular, the roller 21 is pivoted eccentrically on the hexagonal head 23 of a threaded stem 24 inserted in a corresponding nut screw 240, obtained in the lever 13 on the second extremity 13b. In this way, when the threaded stem 24 is unscrewed or screwed, the roller 21 describes an eccentric motion which moves it away from the position corresponding to the cam 15 or approaches it to the position corresponding to the cam 15. Moreover, as Figure 4 shows, in correspondence with the second extremity 13b of the lever 13, and in correspondence with the said nut screw 240, the lever 13 is shaped as a clamp, said clamp being tightened or loosened by means of appropriate screws 25a, 25b. In this way it is simple to lock in position the eccentric system whereon the roller 21 is fastened, to prevent the roller 21 from drifting relative to the cam 15 and, hence, the punching pressure from varying.
The elastic means 16 for contrasting the motion of the punch 9 from the first to the second position bring the punch 9 back to the first position once the interaction between the cam 15 and the second extremity 13b of the lever 13 ceases. In the embodiment of the invention shown in the figures, the elastic means 16 contrasting the motion of the punch 9 from the first to the second position comprise at least a spring 17 connected to lever 13, from the side of the punch 9 relative to the fulcrum 14 of the lever 13. The spring 17 is also inserted at least partially in appropriate seats obtained on the lever 13 and on the support 72 of the plug 7a or 7b. Alternatively, the spring 17 can be connected to the support 72 of the plug 7a or 7b.
To limit the distance of the punch 9 from the punching die 8 when the punch 9 is in the first position, the flanging machine 1 further comprises at least an element 18 for arresting the lever 13. In this way the movements of the device for manufacturing the tactile warnings are minimised. The element 18 for arresting the lever 13 comprises adjustments for modifying the first position of the punch 9. In a preferred embodiment of the invention, as shown in Figure 1, 1a, 1b and 2, an arresting element 18 is provided for each lever 13. The arresting element 18 is made with a threaded pivot pin 180, inserted in a corresponding through nut screw 181 obtained in the lever 13 between the second extremity 13b and the fulcrum 14. The threaded pivot pin 180 presents towards the support 72 of the plug 7a or 7b a checking surface 182 on the support 72 itself, whose distance from the lever 13 can be adjusted by means of the screw-nut screw engagement.
Alternatively and equivalently, the threaded pivot pin 180 can be inserted in a corresponding nut screw obtained on the support 72 of the plug 7a or 7b and present a surface for checking the lever 13 between the second extremity 13b and the fulcrum 14, whose distance from the support 72 can be adjusted by means of the screw-nut screw engagement.
In general in the preferred embodiment of the invention, during use, the containers 2 are carried by the feeding station 4 to the conveyor means 6 and actuated in revolution about the axis 11 in phase both with the drums 12a, 12b and with the pairs of plugs 7a, 7b. The plugs, while moving in revolution motion about the axis 11, translate coaxially towards one another and are inserted in the openings 20a, 20b of the containers 2 to hold the containers 2 tightly and cause their flanging. When the containers 2 are still firmly held by the plugs 7a, 7b and upstream of the off-loading station 5, the plug 7a or 7b and the punch 9 associated thereto meet the cam 15. The second extremity 13b of the lever 13 interacts, through the rolling friction means 19, with the cam 15 itself and causes the motion of the punch 9 from the first to the second position. The punch 9 thus presses on the punching die 8, producing the tactile warning. As soon as the motion of the plug 7a or 7b causes the second extremity 13b of the lever 13 to disengage from the cam 15, the contrasting elastic means 16 cause the punch 9 to move away from the punching die 8 and the punch 9 to return to its first resting position. The punches 7a, 7b, continuing their revolution about the axis 11, at this point move away from each other, freeing the container 2 which can be released by the conveyor means 6 at the off-loading station and sent, already provided with flanging and tactile warnings, to other parts of the line for subsequent work processes.
The invention achieves important advantages.
First of all, the tactile warning is produced together with the flanging so as not to cause any delay on the work times of the flanging machine and, hence of the container production line. In the second place, the various parts of the flanging machine are mutually synchronised automatically by means of the simple mechanical relationship between the parts, so as to eliminate sophisticated independent detecting, timing and synchronising systems. Given its simplicity, the flanging machine of the present invention is also particularly compact and requires relatively little maintenance.
The invention thus conceived can be subject to numerous modifications and variations, without thereby departing from the scope of the inventive concept.
Moreover, all components can be replaced by technically equivalent elements.
In practice all materials employed, as well as the dimensions, can be any, depending on requirements.

Claims

A flanging machine (1) for metallic containers (2) of the type comprising:

a support structure (3);

a station (4) for feeding metallic containers (2) to be flanged, said metallic containers (2) having only lateral walls (20) and openings (20a, 20b) corresponding to bottom and lid;

a station (5) for off loading the flanged metallic containers (2);

means (6) for conveying the containers (2) from the feeding station (4) to the off loading station (5);

at least a pair of flanging plugs (7a, 7b) mutually opposite and coaxial, located downstream of the feeding station (4) and upstream of the offloading station (5), said plugs (7a, 7b) being movable, along their own common axis (70), according to a first component of relative and alternating motion at least between a first configuration, in which the plugs (7a, 7b), are separated by a distance at least corresponding to the height of a container (2) and in which the container (2) is coaxial with the plugs (7a, 7b), and a second configuration in which the plugs (7a, 7b) are inserted forcibly into the openings (20a, 20b) of the container (2) holding it firmly and causing its flanging;

characterised in that it comprises a device for producing tactile warnings on the lateral walls (20) of the container (2) comprising:

at least a punching die (8) bearing the print of the tactile warning and integral with an outer lateral surface (71) of at least one of the plugs (7a or 7b) of the pair;

at least a punch (9) having its head (90) counter-shaped relative to the punching die (8) and movable between a first position distanced from the punching die (8), when the pair of plugs (7a, 7b) is in the first configuration, and a second position of pressure on the punching die (8), when the pair of plugs (7a, 7b) is in the second configuration and the lateral walls (20) of the container are interposed between said die (8) and said punch (9) to produce the tactile warning;

actuator means (10) for actuating the punch (9) between the first and the second position.
A flanging machine (1) as claimed in claim 1, characterised in that the plugs (7a, 7b) are also movable according to a second component of common motion along a trajectory lying in a plane perpendicular to the common axis (70) of the plugs (7a, 7b), the common axis (70) maintaining its own direction constant over time, said second common motion component being in phase with the motion of the containers (2) to be flanged determined by the conveyor means (6).
A flanging machine (1) as claimed in claim 2, characterised in that the second common motion component of the plugs (7a, 7b) is a revolution motion about an axis (11) parallel to the common axis (70) of the plugs (7a, 7b).
A flanging machine (1) as claimed in claim 2 or 3, characterised in that the punch (9) participates in the motion of the pair of plugs (7a, 7b).
A flanging machine (1) as claimed in claim 4, characterised in that the actuator means (10) for actuating the punch (9) comprise at least an element fixed to the support structure (3), located in a predetermined point of the trajectory of the second motion component of the plug (7a or 7b) and interacting with the punch (9) when the punch (9) is in correspondence with said predetermined point, to cause the punch (9) itself to move from the first to the second position.
A flanging machine (1) as claimed in claim 5, characterised in that the punch (9) is rigidly connected to a lever (13), the fixed element of the actuator means (10) interacting with the lever (13), said lever (13) being subject to elastic means (16) contrasting the motion of the punch (9) from the first to the second position, to return the punch (9) to the first position once the interaction between the fixed element and the lever (13) ceases.
A flanging machine (1) as claimed in claim 6, characterised in that the lever (13) has its fulcrum (14) associated to a support (72) of the plug (7a or 7b) on whose outer lateral surface (71) is located the punching die (8), the punch (9) being rigidly connected to a first extremity (13a) of the lever (13), a second extremity (13b) of the lever (13) being opposite to the first extremity (13a) relative to the pivot (14) and being destined to interact with the fixed element of the actuator means (10), said fixed element being constituted by a cam (15) shaped in such a way as to determine the motion of the punch (9) between the first and the second position.
A flanging machine (1) as claimed in claim 7, characterised in that the position of the cam (15) is adjustable in space.
A flanging machine (1) as claimed in claim 7 or 8, characterised in that it further comprises at least an element (18) for arresting the lever (13) to limit the distance of the punch (9) from the punching die (8) when the punch (9) is in the first position.
A flanging machine (1) as claimed in claim 9, characterised in that the element (18) for arresting the lever (13) is provided with adjustment capabilities to modify the first position of the punch (9).
A flanging machine (1) as claimed in any claim from 7 to 10, characterised in that the lever (13) presents, in correspondence with the second extremity (13b), rolling friction means (19) to favour its sliding on the cam (15).
A flanging machine (1) as claimed in claim 11, characterised in that the position of the rolling friction means (19) relative to the lever (13) is adjustable, to allow the adjustment of the pressure of the punch (9) on the punching die (8).
A flanging machine (1) as claimed in any of the previous claims, characterised in that a head (73) of the plug (7a or 7b) on whose outer lateral surface (71) is located the punching die (8) presents, at least towards the punching die (8), a diameter greater than the diameter of the body of the plug (7a or 7b), to allow the insertion of the plug (7a or 7b) into the opening (20a or 20b) of the container (2) without sticking on the die (8) itself.