Method and unit for applying labels

Abstract: A method and unit for applying labels to packets of cigarettes (3), traveling in a given direction (D1) along a first path (P1) with a given spacing (P) and arranged a given distance (I) apart, provide for feeding a gripping head (33) along a second path (P2), and applying each label (2) to a first face (9) of a respective packet (3) by inserting the gripping head (33) between one packet (3) and the adjacent following packet (3) to roll the gripping head (33) and apply the label (2) along the first face (9), which is perpendicular to the given direction (D1).

Description: The present invention relates to a method of applying labels. More specifically, the present invention relates to a method of applying labels to packets of cigarettes, to which the following description refers purely by way of example. Known methods of applying labels to packets of cigarettes comprise feeding the packets of cigarettes in a given direction along a first path; withdrawing the labels by means of a gripping head from the outlet of a store; feeding the gripping head and relative label along a given second path; and applying each label to a respective packet, on a face parallel to the traveling direction of the packet and/or a face perpendicular to the given traveling direction. For example, US 5,645,669 and US 1,693,965 disclose a method, according to which the gripping head is inserted between one packet and the adjacent following packet so as to apply a label to a face of the packet; the face being perpendicular to the given traveling direction. US 1,693,965 discloses a unit according to the preamble of claim 12. Units implementing the above methods require a relatively very good co-ordination of the movements of the gripping head and the packet in order to ensure precise application of the label itself. Controlling the movements of the gripping head and the speed of the packet, however, is extremely difficult, particularly when a high degree of precision is required. The accuracy with which the label is applied is extremely important in the case of revenue stamps applied to hinged-lid packets of cigarettes and having tear lines. Hinged-lid packets of cigarettes comprise a cup-shaped body and a lid separated from the cup-shaped body by a parting line; and labels with tear lines must be applied extremely accurately so that the tear line corresponds to the parting line. Otherwise, the tear line remains intact, and therefore serves no purpose, when the packet is unsealed. It is an object of the present invention to provide a method of applying labels, designed to eliminate the drawbacks of known methods. According to the present invention, there is provided a method of applying labels to packets as claimed in Claim 1. The present invention also relates to a unit for applying labels. According to the present invention, there is provided a unit for applying labels to packets as claimed in Claim 12. 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 plan view, with parts removed for clarity, of a unit for applying labels in accordance with the present invention; Figure 2 shows a view in perspective of a packet bearing a label applied using the method according to the present invention; Figures 3 to 5 show plan views, with parts removed for clarity, of details of the Figure 1 unit at successive steps in the method according to the present invention; Figure 6 shows a section of a detail of the Figure 1 unit along line VI-VI. Number 1 in Figure 1 indicates as a whole a unit for applying labels 2 to packets 3 of cigarettes traveling continuously along a path P1 extending in a direction D1. As shown more clearly in Figure 2, packets 3 are rigid hinged-lid types. Each packet 3 comprises a cup-shaped body 4 and a lid 5, and, once label 2 is applied, has a label 2 applied partly to lid 5 and partly to cup-shaped body 4. When lid 5 is in the closed position, packet 3 has a front face 6, a rear face 7, a bottom face 8, a top face 9, and two lateral faces 10 and 11. Lid 5 and cup-shaped body 4 are hinged along rear face 7 and are separated by a parting line 12 along front face 6 and by two parting lines 13 along respective lateral faces 10 and 11. Label 2 has a central portion 14 adhering to top face 9; an end portion 15 adhering to lateral face 10; and an end portion 16 adhering to lateral face 11. Central portion 14 and portion 16 adhere solely to lid 5, whereas portion 15 adheres partly to lid 5 and partly to cup-shaped body 4. Portion 15 is in turn divided into two parts 17 and 18 by a tear line 19 extending along parting line 13 along wall 10. With reference to Figure 1, unit 1 comprises a transfer wheel 20; a store 21 of labels 2; a conveyor 22 for packets 3; a cutting device 23; and a gumming device 24. Store 21 comprises guides 25 for maintaining labels 2 in a pack and for guiding each label 2 to an outlet of store 21 in a given pickup position in which label 2 lies and is maintained by two teeth of guides 25 in a vertical plane. The store comprises a pusher S for feeding the pack of labels 2 towards the outlet. Conveyor 22 comprises a support 26, shown by the dash lines in Figure 1, on which packets 3 are equally spaced with top faces 9 perpendicular to direction D1 and front faces 6 facing support 26. Along path P1 of conveyor 22, two fixed folding devices 27 and 28 are provided on opposite sides of conveyor 22 so as to contact respective lateral faces 10 and 11 of each packet 3. Wheel 20 comprises a central hub 29 rotating continuously clockwise, in Figure 1, about a respective vertical axis 30; and a number of arms 31 rotating, with respect to hub 29, about respective axes 32 parallel to and equally spaced about axis 30. Each arm 31 is fitted on the end with a gripping head 33, which rotates about an axis 34 parallel to axis 30 and is fed along a path P2. With reference to Figure 6, each arm 31 comprises a hollow body 35 integral with a sleeve 36, which rotates about axis 32 and is integral with a lever 37 having a roller 38 which engages a cam (not shown) to position arm 31 according to the angular position assumed by axis 32 of respective arm 31 about axis 30. Gripping head 33 has a gripping wall 39 in the form of a cylindrical sector extending about axis 34, and which has a number of suction holes 40 for retaining label 2 on gripping wall 39. Gripping head 33 is integral with a shaft 41 mounted for rotation about axis 34 and in turn integral with a pulley 42. Sleeve 36 is fitted inside with a shaft 43, which rotates about axis 32 and is fitted, on the top end, with a pulley 44 larger in diameter than pulley 42, and, on the bottom end, with a rocker arm 45 having two rollers 46 which engage respective cams (not shown) for rotating pulley 44 about axis 32 according to the angular position assumed by axis 32 about axis 30. A belt 47 is looped about pulleys 44 and 42 to transmit rotation from pulley 44 to pulley 42; and a suction channel 48 is formed inside hub 29, sleeve 36, hollow body 35, shaft 41 and gripping head 33 to selectively activate suction holes 40. With reference to Figure 1, cutting device 23 comprises a supporting member 49 supporting a blade 50 in a fixed position with respect to path P2; and gumming device 24 comprises a gumming spray nozzle 51 also in a fixed position along path P2. In actual use, unit 1 for applying labels 2 feeds packets 3 along path P1 in direction D1, with top faces 9 perpendicular to and at the front with respect to traveling direction D1, and with packets 3 equally spaced along support 26 with a given spacing P and a gap I between each packet 3 and the adjacent following packet 3. Hub 29 is rotated continuously about axis 30, arms 31 are oriented about axes 32 according to the angular position assumed by axes 32 about axis 30, and gripping heads 33 are rotated about axes 34 also according to the angular position assumed by axes 32 about axis 30. Each gripping head 33 is fed along endless path P2, which intersects path P1 at two points A and B; and, along path P2, each gripping head 33 travels past store 21, cutting device 23 and gumming device 24. As gripping head 33 nears store 21, arm 31 is rotated clockwise about axis 32 so that gripping wall 39 contacts the label 2 in the pickup position inside store 21. Once wall 39 contacts label 2, arm 31 is rotated anticlockwise in Figure 1, so that the combined rotations about axis 30 and axis 32 arrest gripping head 33 at the point of contact between wall 39 and label 2. And, while gripping head 33 is stationary, suction holes 40 are activated, and gripping head 33 then moved along a straight portion T1 of path P2. As shown more clearly in Figure 3, along portion T1, the suction through holes 40 is maintained, and gripping head 33 is rotated about axis 34 by rocker arm 45 and the mechanical transmission defined by pulleys 42 and 44 and belt 47, which transmits rotation to gripping head 33. As gripping head 33 rotates about axis 34 and is moved along straight portion T1, gripping wall 39 rolls along label 2, which, by virtue of the suction through holes 40, adheres to gripping wall 39 and is gradually withdrawn from the outlet of store 21. Gripping head 33 is then fed, together with label 2, along a straight portion T2 of path P2 past cutting device 23, as shown more clearly in Figure 4, and is rotated about axis 34 so that label 2 contacts fixed blade 50 to form tear line 19. With reference to Figure 1, at gumming device 24, arm 31 is first rotated clockwise in Figure 1 and then anticlockwise to form a pointed portion T3 of path P2; and gripping head 33 is rotated about axis 34 along portion T3 to position the whole surface of label 2 in front of nozzle 51 which gums label 2. Gripping head 33 is then fed along a portion T4, along which gripping head 33 is positioned inside the gap I between one packet 3 and the adjacent following packet 3, and wall 39 is brought into contact with and rolled along top face 9 of the following packet 3. In other words, with reference to Figure 5, gripping head 33 and respective label 2 are brought into a position of interference with respect to a packet 3 traveling in direction D1, and in which label 2 is brought into contact with top face 9 of packet 3. At this stage, suction holes 40 are deactivated, and wall 39 rolls along top face 9 to lay label 2 gradually on top face 9. Portion 15 projects with respect to lateral face 10 and is folded onto face 10 by fixed folding device 27. In the meantime, gripping head 33 lays the whole of central portion 14 of label 2 on top face 9 so that portion 16 projects with respect to lateral face 11; and gripping head 33 is then fed along path P2 between fixed folding devices 27 and 28, and packet 3 is brought into contact with fixed folding device 28 to fold portion 16 onto lateral face 11. The present invention is particularly advantageous by preventing relative slippage of the packet and label as the label is applied, thus ensuring a high degree of precision; by enabling the free portions to be folded by fixed folding devices; and by the highly maneuverable gripping head greatly simplifying the cutting and gumming devices.

Claims: A method of applying labels (2) to packets (3), in particular packets of cigarettes, travelling in a given direction (D1) along a first path (P1) with a given spacing (P) and arranged a given distance (I) apart; the method comprising feeding a gripping head (33) along a second path (P2), applying a said label (2) to a first face (9) of a relevant said packet (3) perpendicular to said given direction (D1), and inserting said gripping head (33) between one packet (3) and the adjacent following packet (3) to apply said label (2) along said first face (9); wherein said gripping head (33) comprises a gripping wall (39) in the form of a cylindrical sector having gripping means (40), and wherein a central hub (29) is rotating about a first axis (30), an arm (31) is rotating with respect to said hub (29) about a second axis (32) parallel to said first axis (30), and said gripping head (33) is fitted on the arm end and is rotating with respect to the arm (31) about a third axis (34) parallel to said first and second axis (30, 32). A method as claimed in Claim 1, characterized in that said second path (P2) is an annular path intersecting the first path (P1) at two points (A, B). A method as claimed in Claim 1 or 2, characterized in that said gripping head (33) is fed along a straight first portion (T1) of the second path (P2). A method as claimed in one of Claims 1 to 3, characterized in that said label (2) comprises a central portion (14) which is positioned contacting said first face (9); and at least a first portion (15) which is positioned contacting a second face (10) of the packet (3); said second face (10) being parallel to said given direction (D1); and the method providing for folding said first portion (15) by means of a fixed first folding device (27) located along the first path (P1). A method as claimed in Claim 4, characterized in that said label (2) comprises a second portion (16) which is positioned contacting a third face (11) of the packet (3); said third face (11) being parallel to said given direction (D1); and the method providing for folding said second portion (16) by means of a fixed second folding device (28) located along the first path (P1). A method as claimed in one of Claims 1 to 5, characterized in comprising rolling the gripping head (33) on said first face (9). A method as claimed in anyone of the preceding Claims, characterized in comprising feeding said gripping head (33) along a straight first portion (T1) of the second path (P2), and rolling said gripping wall (39) on a label (2) located at an output of a store (21) of labels (2). A method as claimed in Claim 7, characterized in that said gripping head (33) is stopped at a point along the straight said first portion (T1); said gripping means (40) being activated at said stop point of the gripping head (33) when said gripping wall (39) contacts a label (2). A method as claimed in Claim 7 or 8, characterized in comprising feeding said gripping head (33) along a straight second portion (T2) of the second path (P2), the straight said second portion (T2) being located opposite a fixed blade (50); and by rotating said gripping head (33) about said third axis (34) to bring different parts of the label (2) into contact with the fixed blade (50) and form a tear line (19) on said label (2). A method as claimed in any one of Claims 7 to 9, characterized in comprising feeding said gripping head (33) along a third portion (T3) of the second path (P2), and rotating the gripping head (33) about the third axis (34) along the third portion (T3); said third portion (T3) being pointed and located opposite a gumming spray nozzle (51) for gumming the label (2) retained by the gripping wall (39). A method as claimed in any one of the preceding Claims, characterized in that said first, said second and said third axis (30, 32, 34) are vertical. A unit for applying labels (2) to packets (3), in particular packets of cigarettes, travelling in a given direction (D1) along a first path (P1) with a given spacing (P) and arranged a given distance (I) apart; the unit comprising at least one gripping head (33) movable along a second path (P2) to apply a said label (2) to a first face (9) of a relevant said packet (3) perpendicular to said given direction (D1), and at least one movable arm (31) for inserting said gripping head (33) between one packet (3) and the adjacent following packet (3) to apply said label (2) along said first face (9); the unit (1) being characterized in that said gripping head (33) comprises a gripping wall (39) in the form of a cylindrical sector having gripping means (40), and in that a central hub (29) is rotating about a first axis (30), an arm (31) is rotating with respect to said hub (29) about a second axis (32) parallel to said first axis (30), and said gripping head (33) is fitted on the arm end and is rotating with respect to the arm (31) about a third axis (34) parallel to said first and second axis (30, 32). A unit as claimed in Claim 12, characterized in that said second path (P2) is an endless annular path intersecting the first path at two points (A, B). A unit as claimed in Claim 12 or 13, characterized in that said second path (P2) has at least a straight first portion (T1). A unit as claimed in one of Claims 12 to 14, characterized in that said label (2) comprises a central portion (14) which adheres to said first face (9); and at least a first portion (15) which adheres to a second face (10) of the packet (3); said second face (10) being parallel to said given direction (D1); and the unit comprising a fixed first folding device (27) located along said first path (P1) to fold said first portion (15) onto the second face (10). A unit as claimed in Claim 15, characterized in that said label (2) comprises a second portion (16) opposite the first portion (15); the second portion (16) adhering to a third face (11) parallel to the second face (10); and the unit comprising a fixed second folding device (28) located along said first path (P1) to fold said second portion (16) onto said third face (11). A unit as claimed in Claim 16, characterized in that said second folding device (28) is located downstream from said first folding device (27). A unit as claimed in one of Claims 12 to 17, characterized in comprising a mechanical transmission (42, 44, 47) housed in said arm (31) to rotate said gripping head (33) about said third axis (34). A unit as claimed in Claim 18, characterized in that said mechanical transmission (42, 44, 47) comprises a first pulley (42) rotating about the third axis (34), and a second pulley (44) rotating about the second axis (32). A unit as claimed in one of Claims 12 to 19, characterized in comprising a store (21) of labels (2), a cutting blade (50) and a gumming nozzle (51), which are located in succession along said second path (P2). A unit as claimed in Claim 20, characterized in that said blade (50) and said nozzle (51) are fixed with respect to said second path (P2). A unit as claimed in one of Claims 12 to 21, wherein said gripping means (40) comprises suction holes.

Inventors: SPATAFORA MARIO, TALE FABRIZIO, SPATAFORA, MARIO, TALE', FABRIZIO
Applicants: GD SPA, G.D SOCIETA' PER AZIONI
Application year: 2001
Main classification: B65C1
IPC codes: B65C9, B65C1