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(11) | EP 0 792 804 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Method and device for supplying cigarettes on a cigarette packing machine |
| (57) A method and device for supplying cigarettes (2) on a packing machine, whereby the
cigarettes (2) are withdrawn successively from the output ends (12) of a number of
channels (8) by means of a number of pickup rollers (16) - one for each channel (8)
- located parallel to the cigarettes (2) and each having a rib (19) defining a suction
type pickup seat (20) for a respective cigarette (2); each pickup roller (16) rotating
variably about a respective axis (17) so that the respective rib (19) sweeps past
the output end (12) of the respective channel (8) at a relatively slow angular speed,
and the respective cigarette (2) is transferred at a relatively fast angular speed
to a device (5) for forming layers (6). |
[0001] The present invention relates to a method of supplying cigarettes on a cigarette packing machine.
[0002] More specifically, the present invention relates to a method of supplying cigarettes on a continuous cigarette packing machine.
[0003] On continuous packing machines, and as described for example in European Patent Application n. 667,286, the cigarettes are supplied to a group forming device - each group being defined by a number of cigarettes arranged in a number of superimposed layers - by a supply device comprising a feedbox with at least one outlet in turn comprising a number of substantially vertical, side by side channels. In use, each channel is engaged by a respective column of cigarettes, which are fed by force of gravity and crosswise to their longitudinal axis towards the open bottom end of the channel.
[0004] Again according to European Patent Application n. 667,286, provision is made at the outlet of each channel for a rotary pickup device defined by a pickup roller rotating at constant speed about its axis parallel to the axis of the cigarettes in the respective column, and located beneath the open end of the respective channel. Each pickup roller comprises at least one longitudinal rib defining, outwards of the periphery of the pickup roller, a respective suction type pickup seat for receiving and retaining a respective cigarette; and the side of each channel is open up to a height at least equal to the diameter of a cigarette to enable the pickup roller to be positioned tangent to the open end of the channel, so that the respective pickup seat sweeps past the end of the channel to withdraw the cigarettes one by one in a direction crosswise to both the channel and the longitudinal axis of the cigarettes, and feed them successively on to a conveyor for conveying layers of cigarettes and located substantially tangent to the pickup roller.
[0005] The substantially constant speed of the pickup seats of the supply device described above depends directly on the output capacity of the packing machine, and, at the speeds demanded of modern packing machines, is such as to easily damage the cigarettes as they are withdrawn from the bottom ends of the respective channels.
[0006] The above drawback is avoided, on the other hand, in the supply device described in European Patent Application n. 512,493, in which the pickup rollers rotate at relatively slow speed - so that the cigarettes withdrawn from the open ends of the respective channels are subjected to no more than acceptable stress - and feed the cigarettes successively on to a conveyor for forming layers of cigarettes and which is defined by a drum rotating variously about its axis. As such, the drum may be rotated at the same surface speed as the pickup rollers when transferring the cigarettes from the pickup rollers to respective seats arranged side by side on the drum and for receiving the cigarettes in a given layer of a group of cigarettes, and may be rotated at a much faster speed when transferring the layers of cigarettes on to a conveyor for forming groups of cigarettes.
[0007] The supply method of the above known device, however, is not without drawbacks of its own, in that the layer forming drum necessarily presents a relatively large diameter, and, being subjected to continual variations in speed, generates vibration resulting in a relatively high noise level and a relatively poor degree of reliability of the packing machine.
[0008] It is an object of the present invention to provide a method of continuously forming groups of cigarettes, designed to overcome the aforementioned drawbacks.
[0009] According to the present invention, there is provided a method of supplying cigarettes on a cigarette packing machine, the method comprising the steps of feeding at least one column of cigarettes in a first traveling direction crosswise to the cigarettes, and along a respective channel having an output end; successively engaging the cigarettes in said column at the output end of the channel by means of a pickup element facing the output end of the channel and having at least one pickup seat for receiving a cigarette from the output end of the channel; and moving the pickup element along a given path to successively withdraw the cigarettes from the channel in a second direction substantially crosswise to both the first direction and the cigarettes, and to transfer the cigarettes to group forming means for forming groups of cigarettes; each group comprising a number of superimposed layers of cigarettes; and said group forming means being located substantially tangent to said path; the method being characterized in that said pickup element is moved along said path at variable speed, so that said pickup seat travels past the output end of the channel at a first relatively slow speed, and each cigarette is transferred from said pickup seat to said group forming means at a second relatively fast speed.
[0010] The present invention also relates to a device for supplying cigarettes on a cigarette packing machine.
[0011] According to the present invention, there is provided a device for supplying cigarettes on a cigarette packing machine, the device comprising a number of channels, each having an output end and each housing a respective column of cigarettes to transversely feed the cigarettes in the respective column to the respective output end in a first traveling direction; a pickup element facing the output end of each channel; first drive means for moving each pickup element along a given path extending in a second direction crosswise to said first direction and the respective channel; group forming means for forming groups of cigarettes, each group comprising a number of superimposed layers of cigarettes, and said group forming means being located substantially tangent to said path; and at least one longitudinal peripheral pickup seat formed on each pickup element and for receiving a cigarette from the output end of the respective channel, and feeding the cigarette to said group forming means; the device being characterized in that said first drive means provide for moving said pickup elements at variable speed, so that said pickup seats travel past the output ends of the respective channels at a first relatively slow speed, and past said group forming means at a second relatively fast speed.
[0012] A non-limiting embodiment of the present invention will be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a schematic side view, with parts in section, parts in block form, and parts removed for clarity, of a preferred embodiment of the cigarette supply device according to the present invention and in a first operating position;
Figure 2 shows a detail of Figure 1 in a different operating position.
[0013] Number 1 in the accompanying drawings indicates a device for supplying cigarettes 2 on continuous packing machines. Device 1 comprises a feedbox 3 in which cigarettes 2 are stored; a pickup device 4 located beneath, and for successively withdrawing cigarettes 2 from, feedbox 3; and a group forming device 5 located beneath device 4 and for successively receiving cigarettes 2 from device 4 to form, firstly, a succession of layers 6, each defined by a given number of side by side cigarettes 2, and, secondly, a succession of groups 7 by superimposing two or more layers 6.
[0014] Feedbox 3 comprises a number of substantially vertical, side by side output channels 8 equal in number to the cigarettes 2 in each layer 6. Each channel 8 comprises a substantially vertical longitudinal axis 9, and is defined by two lateral walls 10 and 11 separated by a distance approximately equal to but no smaller than the diameter of cigarette 2. Each channel 8 also comprises a bottom opening 12; and respective wall 11 comprises, at the bottom end, a gap 13 of the dimensions specified later on.
[0015] In use, the cigarettes 2 inside each channel 8 define a column 14 in which cigarettes 2 are arranged substantially horizontally one on top of the other, and are fed by force of gravity, in a direction 15 crosswise to their longitudinal axes and parallel to axis 9, to respective opening 12 where pickup device 4 is located.
[0016] For each channel 8, device 4 comprises a respective pickup roller 16 located beneath respective channel 8 and rotating about a horizontal axis 17 parallel to walls 10 and 11 and perpendicular to axis 9 and direction 15. Each roller 16 is located with its peripheral surface 18 facing and closing opening 12 of respective channel 8, and comprises at least one longitudinal rib 19 (only one shown) extending outwards of surface 18 and defining a suction type pickup seat for a respective cigarette 2. More specifically, the distance between surface 18 of each roller 16 and the output end of respective channel 8 is such as to allow rib 19 to travel beneath channel 8 without touching it, and to define, at gap 13 of respective wall 11, a passage 21 of a width at least equal to the diameter of cigarette 2.
[0017] Each roller 16 is rotated (clockwise in Figure 1) about respective axis 17 and at variable angular speed by a respective drive unit 22, to withdraw cigarettes 2 successively from opening 12 of respective channel 8 in a direction crosswise to respective axis 9 and direction 15, and transfer them to device 5 through respective passage 21.
[0018] In Figure 1, rollers 16 are preferably, but not necessarily, divided into two separate supply assemblies 23, and group forming device 5 comprises a main conveyor roller 24 located beneath feedbox 3 and for forming layers 6, and a further two intermediate conveyor rollers 25, each of which has a relatively small diameter as compared with main roller 24 but a much larger diameter than rollers 16, and is interposed between main roller 24 and a respective assembly 23 to receive cigarettes 2 from assembly 23 and feed them on to main roller 24.
[0019] Each intermediate roller 25 is mounted for rotation about a respective axis 26 parallel to axes 17, is substantially tangent to main roller 24 and each of rollers 16 forming part of respective assembly 23, and comprises a number of peripheral longitudinal suction seats 27 arranged in groups 28 equally spaced about axis 26 and each comprising a number of seats 27 equal to the number of cigarettes 2 defining layer 6. Each group 28 on one of intermediate rollers 25 corresponds with a group 28 on the other intermediate roller 25; and, within each group 28 on each intermediate roller 25, the seats 27 - hereinafter indicated 27a - for successively receiving cigarettes 2 from relative rollers 16 are equal in number to relative rollers 16, alternate with dead seats 27b, i.e. having no suction, and each correspond with a dead seat 27b in the corresponding group 28 on the other intermediate roller 25.
[0020] Each roller 25 is connected to a respective drive unit 29 by which it is rotated (anticlockwise in Figure 1) about respective axis 26 at an angular speed which, as explained later on, is preferably constant but which may also be varied in a given manner.
[0021] Main roller 24 is mounted for rotation about a respective axis 30 parallel to axes 17, is substantially tangent to intermediate rollers 25 at respective transfer stations 31, and comprises a number of peripheral longitudinal suction seats 32 formed into groups 33 identical to groups 28 and equally spaced about axis 30.
[0022] Main roller 24 is connected to a respective drive unit 34 by which it is rotated about axis 30 at constant angular speed to feed each group 33 of seats 32 through the two stations 31 in time with two corresponding groups 28.
[0023] Device 5 also comprises a known wheel 35 for forming groups 7 from the layers 6 formed on at least three main rollers 24 - only one of which is shown - and is located beneath and tangent to main roller 24 at a transfer station 36. Wheel 35 is mounted for rotation (anticlockwise in Figure 1) about an axis (not shown) parallel to axes 17 and at the same surface speed as main roller 24, and comprises a number of known pockets 37 equally spaced about the periphery of wheel 35 with the same spacing as groups 32, and which provide for receiving respective groups 7 and are fed by wheel 35 through station 36 in time with groups 32. Each pocket 37 receives a respective layer 6 of cigarettes 2 from main roller 24 at station 36, and comprises a known push device 38, which is movable in a radial direction to successively receive layers 6 and to expel group 7 of cigarettes 2 at an unloading station (not shown). Finally, each pocket 37 comprises a pair of known movable lateral inserts 39 for maintaining the intermediate layer 6 of group 7 in position during the formation of group 7.
[0024] In actual use, at the end of its travel along relative channel 8 in direction 15, each cigarette 2 is arrested at relative opening 12 and rests on peripheral surface 18 of relative pickup roller 16 - which provides for closing channel 8 - pending the arrival of relative rib 19 and corresponding pickup seat 20. Drive unit 22 of roller 16 is controlled by a known central control unit (not shown), so that the angular speed of roller 16 is gradually reduced as seat 20 approaches opening 12, and so that seat 20 contacts cigarette 2, and cigarette 2 is removed, crosswise to direction 15, from the output end of channel 8 at the slowest possible speed. Once cigarette 2 is firmly engaged inside pickup seat 20, the angular speed of roller 16 is gradually increased to reach a maximum substantially at a transfer station where cigarette 2 is transferred into a respective seat 27a on relative intermediate roller 25.
[0025] As such, no severe stress is imparted to cigarettes 2 as they are removed from openings 12 of respective channels 8.
[0026] Once cigarettes 2 are fed from rollers 16 of relative assembly 23 into respective seats 27a, each intermediate roller 25 supplies cigarettes 2 to respective transfer station 31. If the variation in the angular speed of rollers 16 - between the minimum value as respective seats 20 travel beneath openings 12 of respective channels 8, and the maximum value as respective seats 20 travel past relative group 28 of seats 27 on relative intermediate roller 25 - is such as to allow wheel 35 to rotate at a sufficiently high surface speed, rollers 25 may be rotated by respective drive units 29 at a constant surface speed equal to the maximum surface speed of relative rollers 16, and to the surface speed of roller 24 and wheel 35. Conversely, if a faster surface speed is required of roller 24 and wheel 35, the speed of rollers 25 is also varied between a minimum as cigarettes 2 are picked up off relative rollers 16, and a maximum as groups 28 travel through stations 31.
[0027] In connection with the above, it should be pointed out that dividing channels 8 and respective rollers 16 into two assemblies 23 - and hence using two rollers 25 - provides not only for using rollers 25 of a much smaller diameter as compared with the corresponding rollers of similar known packing machines, and for easily varying the speed of rollers 25 if necessary, but also for using rollers 16 slightly larger in diameter than the pickup rollers of similar known packing machines, thus enabling the necessary variation in angular speed to be effected more smoothly.
1. A method of supplying cigarettes (2) on a machine for packing cigarettes (2), the
method comprising the steps of feeding at least one column (14) of cigarettes (2)
in a first traveling direction (15) crosswise to the cigarettes (2), and along a respective
channel (8) having an output end (12); successively engaging the cigarettes (2) in
said column (14) at the output end (12) of the channel (8) by means of a pickup element
(16) facing the output end (12) of the channel (8) and having at least one pickup
seat (20) for receiving a cigarette (2) from the output end (12) of the channel (8);
and moving the pickup element (16) along a given path to successively withdraw the
cigarettes (2) from the channel (8) in a second direction substantially crosswise
to both the first direction (15) and the cigarettes (2), and to transfer the cigarettes
(2) to group forming means (5) for forming groups (7) of cigarettes (2); each group
(7) comprising a number of superimposed layers (6) of cigarettes (2); and said group
forming means (5) being located substantially tangent to said path; the method being
characterized in that said pickup element (16) is moved along said path at variable
speed, so that said pickup seat (20) travels past the output end (12) of the channel
(8) at a first relatively slow speed, and each cigarette (2) is transferred from said
pickup seat (20) to said group forming means (5) at a second relatively fast speed.
2. A method as claimed in Claim 1, characterized in that the cigarettes (2) are withdrawn
from a number of said channels (8) equal to the number of cigarettes (2) in each said
layer (6); each channel (8) having a respective said pickup element (16).
3. A method as claimed in Claim 1 or 2, characterized in that each said pickup element
(16) is defined by a pickup roller (16) having a longitudinal axis (17) crosswise
to said first (15) and said second direction and rotated at variable speed about the
respective longitudinal axis (17) by respective drive means (22); each pickup roller
(16) having an outer periphery (18) substantially tangent to both the output end (12)
of the respective channel (8) and to said group forming means (5); and each said pickup
seat (20) being formed on the outer periphery (18) of the respective pickup roller
(16).
4. A method as claimed in Claim 3, characterized in that said layers (6) of cigarettes
(2) are formed on the periphery of a main roller (24), which comprises at least one
group (33) of peripheral seats (32), each for receiving a respective cigarette (2)
of a said layer (6), and is rotated about a respective axis (30) at a third substantially
constant surface speed; each cigarette (2) picked up by the relative pickup roller
(16) being transferred to the respective seat (32) on the main roller (24) via an
intermediate roller (25) substantially tangent to both the pickup roller (16) and
the main roller (24).
5. A method as claimed in Claim 4, characterized in that, of the cigarettes (2) of each
said layer (6), a first number are fed by the relative said pickup rollers (16) to
a first said intermediate roller (25), and a second number are fed to a second said
intermediate roller (25), both tangent to said main roller (24) at respective transfer
stations (31); said first and said second numbers being fed successively into respective
portions of the same group (33) of peripheral seats (32) on the main roller (24).
6. A method as claimed in Claim 5, characterized in that said third speed is equal to
said second speed; said intermediate rollers (25) being rotated at a constant surface
speed equal to said second and said third speed.
7. A method as claimed in Claim 5, characterized in that said intermediate rollers (25)
have a diameter smaller than that of the main roller (24); said third speed being
greater than said second speed; and said intermediate rollers (25) being rotated at
a variable surface speed so as to each receive a respective said number of cigarettes
(2) from the relative pickup rollers (16) at said second speed, and transfer the respective
said number of cigarettes (2) to said main roller (24) at said third speed.
8. A device for supplying cigarettes (2) on a machine for packing cigarettes (2), the
device (1) comprising a number of channels (8), each having an output end (12) and
each housing a respective column (14) of cigarettes (2) to transversely feed the cigarettes
(2) in the respective column (14) to the respective output end (12) in a first traveling
direction (15); a pickup element (16) facing the output end (12) of each channel (8);
first drive means (22) for moving each pickup element (16) along a given path extending
in a second direction crosswise to said first direction (15) and the respective channel
(8); group forming means (5) for forming groups (7) of cigarettes (2), each group
(7) comprising a number of superimposed layers (6) of cigarettes (2), and said group
forming means (5) being located substantially tangent to said path; and at least one
longitudinal peripheral pickup seat (20) formed on each pickup element (16) and for
receiving a cigarette (2) from the output end (12) of the respective channel (8),
and feeding the cigarette (2) to said group forming means (5); the device (1) being
characterized in that said first drive means (22) provide for moving said pickup elements
(16) at variable speed, so that said pickup seats (20) travel past the output ends
(12) of the respective channels (8) at a first relatively slow speed, and past said
group forming means (5) at a second relatively fast speed.
9. A device as claimed in Claim 8, characterized in that said channels (8) are equal
in number to the cigarettes (2) forming a said layer (6).
10. A device as claimed in Claim 8 or 9, characterized in that each said pickup element
(16) comprises a pickup roller (16) having a longitudinal axis (17) crosswise to said
first (15) and said second direction, and connected to the respective said first drive
means (22) so as to rotate at variable angular speed about the respective longitudinal
axis (17); each pickup roller (16) having an outer periphery (18) substantially tangent
to both the output end (12) of the respective channel (8) and said group forming means
(5); and each said pickup seat (20) being formed on the outer periphery of the respective
pickup roller (16).
11. A device as claimed in Claim 10, characterized in that said group forming means (5)
comprise a main roller (24) having at least one group (33) of peripheral seats (32),
each for receiving a respective cigarette (2) of a said layer (6); second drive means
(34) for rotating the main roller (24) about a respective axis (30) at a third substantially
constant surface speed; and at least one intermediate roller (25) for transferring
the cigarettes (2) picked up by at least some of the pickup rollers (16) to the respective
seats (32) on the main roller (24); the intermediate roller (25) being substantially
tangent to the relative pickup rollers (16) and to the main roller (24).
12. A device as claimed in Claim 11, characterized by comprising a first and a second
said intermediate roller (25) for respectively feeding a first and a second number
of the cigarettes (2) of each said layer (6) into respective portions of the same
group (33) of peripheral seats (32) on the main roller (24); said first and said second
intermediate roller (25) being tangent to said main roller (24) at respective transfer
stations (31).
13. A device as claimed in Claim 12, characterized in that said third speed is equal to
said second speed; third drive means (29) being provided to rotate said intermediate
rollers (25) at a constant surface speed equal to said second and said third speed.
14. A device as claimed in Claim 12, characterized in that said intermediate rollers (25)
have a diameter smaller than that of the main roller (24); said third speed being
greater than said second speed; and said third drive means (29) imparting to the respective
intermediate rollers (25) a variable surface speed to enable each intermediate roller
(25) to receive the respective said number of cigarettes (2) from the relative pickup
rollers (16) at said second speed, and to transfer the respective said number of cigarettes
(2) to said main roller (24) at said third speed.
15. A device as claimed in any one of the foregoing Claims from 11 to 14, characterized
in that said group forming means (5) also comprise a conveyor (35) substantially tangent
to said main roller (24) at a third transfer station (36), and having a succession
of conveying pockets (37), each for receiving a respective group (7) of cigarettes
(2); each pocket (37) receiving, at said third transfer station (36), a respective
layer (6) of cigarettes (2) from the main roller (24).