EP4284750B1

EP4284750B1 - System and method for capping containers

Info

Publication number: EP4284750B1
Application number: EP22708604.8A
Authority: EP
Inventors: Fabio PREGNO
Original assignee: Arol SpA
Current assignee: Arol SpA
Priority date: 2021-02-12
Filing date: 2022-02-11
Publication date: 2025-03-12
Anticipated expiration: 2042-02-11
Also published as: EP4284750A1; WO2022172207A1; EP4284750C0; ES3029859T3

Description

Technical Field

The present invention relates to plants for capping containers, especially bottles, and more particularly it relates to a system and method for capping such containers by means of caps with ring to be pulled for opening (so-called ring pull caps) and the like.
For ease and clearness of description, in the following reference will mainly be made to such ring pull caps, but this should not be understood as a limitation of the scope of protection of the invention.

Background Art

Ring pull caps are caps having a ring associated with the cap body, said ring allowing easy removal of the cap from the container, typically a bottle, by simply pulling said ring, without having to use appropriate devices. In plants for capping containers by means of such caps, the caps are taken and pulled away by the bottles, the top of each of said bottles engaging with a cap upon passage of said bottle under a dispenser in which the caps are arranged. As a result of the advancement of the bottle, the cap taken from the dispenser is placed onto the mouth of the bottle and the bottle with the cap then advances towards a capping head which clamps the cap onto the neck of the bottle. The same procedure is also applied to other types of caps without ring.
An example of a plant for applying ring pull caps that can be picked from a dispenser is described in Italian Patent IT 1048729 . Examples of such capping heads for plants of this type are described in patent documents CN 2656290 Y , CN 203269516 U , DE 3924120 A1 , GB 1185988 A , US 4621481 .
US 2647672 discloses a system for capping containers according to the preamble of claim 1 and a method for capping containers according to the preamble of claim 6.
Capping systems with pressing members are known from EP 3133027 and US 4295320 .
In these plants there is the problem that, during travel of the bottle between the dispenser and the capping head, the cap can move away from the mouth of the bottle due to vibrations of the plants or due to gases or foam, in the case of carbonated drinks or foamed drinks, such as beer, thus preventing proper capping. It is thus necessary to adopt measures for holding the cap in the correct position on the bottle until the end of the capping operation. In several known plants, this is achieved by means of a guide plate, which prevents the caps from moving during traveling of the bottle towards the capping head. It is clear that the guide plate must end at the capping zone in order to allow the capping head to perform axial movements necessary for clamping the cap, and therefore there is still some time left during which the cap can experience a movement relative to the bottle.

Summary of Invention

The object of the invention is to provide a system and a method that guarantee that the caps are held in the correction position until clamping is completed.
According to a first aspect of the invention, there is provided a system for capping containers according to claim 1, by means of ring pull caps that are taken from a dispenser by the containers themselves, wherein a guide plate is provided along the path of the containers between the cap-taking zone and the capping zone, which guide plate is arranged above the containers at a height such that the caps are held on the containers and ends at the capping zone. The guide plate has a longitudinal slot in an end part thereof adjacent to the capping zone, and the capping heads of the system are provided each with a pressing member shaped so as to be able to pass through the slot and associated with elastic control means that push said pressing member towards the cap on a container and keep the cap in contact with the container even beyond the end of the guide plate, until capping is completed.
The pressing member can be mounted inside a hollow guide rod integral for the axial movement with a pushing member intended to cooperate with the pressing member for keeping a cap pressed against the mouth of the container when the capping head has come into contact with the container.
Alternatively, the pressing member can be mounted directly inside the pushing member and be integral thereto for the axial movement.
Advantageously, the longitudinal slot begins slightly before a point in which the axis of a container becomes aligned with the axis of the corresponding capping head and ends at the end of the guide plate, where said longitudinal slot is open.
According to another aspect of the invention, there is provided a method for capping containers according to claim 6, by means of caps that can be taken and pulled away from a dispenser by the containers themselves, in which there is provided a step of guiding the containers, along their traveling between the cap-taking zone and the capping zone, by means of guide plate that is arranged above the containers at a height such that the caps are held on the containers and ends at the capping zone. In the method, the step of guiding the containers is performed by means of guide plate having a longitudinal slot in an end portion thereof adjacent to the capping zone, and there are further provided the following steps:

equipping each capping head with a pressing member arranged to engage the cap by passing through the slot; and
controlling the pressing member by means of elastic control means that push said pressing member through the slot and towards the cap applied to a container and keep the pressing member in contact with the cap even after the container has moved beyond the guide plate, until capping is completed.

Brief Description of Drawings

These and other features and advantages of the present invention will become apparent from the following description of a preferred embodiment given by way of non-liming example with reference of the annexed Figures, in which:

Fig.1 is an isometric partial view of a capping plant which is intended for ring pull caps and the like and to which the invention is applied;
Fig.2 is a view of the inlet star wheel and capping turret of the plant of Fig. 1, taken from a different viewpoint;
Fig.3 is a schematic lateral view showing the cooperation between a capping head and a guide plate according to the invention, in several steps of a capping operation;
Fig.4 is a further schematic lateral view showing the cooperation between a capping head and a guide plate according to the invention, in several steps of a capping operation;
Fig.5 is a further schematic lateral view showing the cooperation between a capping head and a guide plate according to the invention, in several steps of a capping operation;
Fig.6 is a sectional view of a capping head in which the invention is used, in several steps of a capping operation;
Fig.7 is a further sectional view of a capping head in which the invention is used, in several steps of a capping operation;
Fig.8 is a further sectional view of a capping head in which the invention is used, in several steps of a capping operation.

Description of Embodiments

Referring to Figs. 1 and 2, a capping plant has been indicated as a whole with reference numeral 1, said capping plant being intended for applying caps 3, which in the described embodiment as illustrated in the figures are caps with ring 3A to be pulled for opening, to containers 2, especially bottles. As mentioned, the invention, however, is not limited to caps of this type, but it applies also to other types of caps that do not have such ring.
The plant 1 comprises, in a conventional manner:

a capping turret 10, hereinafter simply referred to as "capper", which has a plurality of capping heads 13, evenly distributed along the circumference thereof and associated each with a drive assembly 19 controlling the axial movements thereof necessary for bringing said capping heads into contact with the caps 3 and clamp said caps onto the bottles 2;
an inlet star wheel 11, which feeds the capper 10 with the bottles 2 to be capped, which bottles, in the capper 10, will be received on appropriate holders 14 and centered relative to the capping heads by means of centering members 20; and
an outlet star wheel 12, which receives the capped bottles 2 from the capper 10 and delivers them to a subsequent working station.

The capper 10 and the inlet and outlet star wheels 11, 12 rotate in a mutually synchronous manner, for example in the directions shown by arrows A, B, C in Fig. 1.
During rotation of the inlet star wheel 11 carrying the bottles 2 towards the capper 10, the bottles 2 pass by a dispenser or dispensing channel 15 containing the caps 3 coming from a feeder (not shown) provided on the turret 10, and take and pull away the caps 3 by engaging with the inner rim thereof, so that each cap becomes arranged onto the mouth of a respective bottle, onto which it will then by clamped by the corresponding head 13.
Still in a conventional manner, the plant 1 further comprises a guide plate 16 extending over the bottles 2 and being substantially parallel to a platform 11A that carries the bottles 2 into the inlet star wheel 11. The vertical position of the guide plate 16 must be such as not to hinder advancement of the bottles 2, taking into account that a certain height tolerance is provided for them, while at the same time preventing the caps 3 from slipping off the bottles as a result of vibrations of the plant and/or as a result of gases or foam, in the case of carbonated drinks or foamed drinks such as beer and the like. For example, if the height tolerance is in the order of ± 1,5 mm, the guide plate 16 will be arranged about 2 mm above the nominal height of the bottles. The guide plate 16 essentially begins at the dispenser 15 and ends in the capping zone, in a point such as to allow the capping heads 13 to complete their downward axial movement necessary for capping.
Referring also to Figs. 3-5, according to the invention, in order to guarantee that the caps 3 are held in position also after the bottles have moved beyond the end of the guide plate 16, said guide plate has, in its end portion adjacent to the capper 10, a longitudinal slot 17 open at the end of the guide plate, and the capping heads 13 have each a pressing member 18 formed so as to be able to pass through the slot 17. The slot 17 begins in a region of the guide plate where a capping head 13, during the capping operation, has moved downward essentially to the height of the guide plate (see Fig. 3): more particularly, the initial point of the slot 17 is preferably located slightly before the point of tangency between the inlet star wheel 11 and the turret 10, i.e. the point in which the axis of a bottle 2 becomes aligned with the axis of the capping head 13 and said head starts moving axially downwards in order to perform capping. The pressing member 18 is associated with elastic control means, described below, which hold it in a position of downward thrust, in which its lower portion protrudes from the capping head 13, so that, when the rotation of the turret 10 brings the capping head 13 to the slot 17, said pressing member passes through said slot and comes into contact with the cap 3, as can be seen in Fig. 4. Subsequently, when the capping head 13 goes beyond the end of the guide plate 16 (see Fig. 5), a further downward movement of the capping head 13 causes lifting of the pressing member 18 upwards, as will be better described in connection with the operation of the system.
Referring to Figs. 6-8, there is shown the structure of the capping head 13 in several steps of a capping operation. In particular, the position shown in Fig. 6 corresponds to the one shown in Fig. 4, with the pressing member 18 in contact with the cap 3 but not biased upwards, and Fig. 8 shows the capping head 13 essentially at the end of its axial travel, in its position where it starts clamping the cap 3 onto the bottle 2. Fig. 7 is an intermediate position between the positions of Figs. 6 and 8. For the sake of simplicity, the guide plate 16 is not shown in said figures.
The capping head 13 comprises a substantially cylindrical hollow body 100 housing a clamping bell 101 mounted in a guide sleeve 102. The assembly bell 101 - sleeve 102 is kept pressed downwards by a spring 103 arranged between the upper face of the sleeve 102 and the ceiling of the body 100, and can be moved axially upwards within the body 100 against the action of the spring 103 during the downward movement of the capping head 13, after the pressing member 18 has reached the cap 3. The clamping bell 101 advantageously comprises a plurality of arms arranged circumferentially, as described, for example, in document US 4621481 A , said arms having a lower end portion 121 which is flared outwards and intended to cooperate with a cam 104 having a complementary shape. In the lower end portion of each arm there is further provided a tooth 105 which radially projects inwards and is intended to engage the outer lateral surface of the cap 3 in order to deform it and clamp the cap against the bottle 2 when the flared portion 121 of the clamping bell 101, as a result of the upward movement thereof, engages the cam 104.
Inside the clamping bell 101 there is provided an ejector or pushing member 106 mounted in a guide sleeve 107 and intended to cooperate with the pressing member 18 in order to keep the cap 3 pressed against the mouth of the bottle 2 when the capping head 13 has come into contact therewith (Fig. 7). To this aim, the ejector 106 is axially biased by a spring 108 arranged between the inner face of a shoulder 109 of the sleeve 107 and an annular flange 110A of the outer surface of a hollow rod 100, described below. The ejector 106, too, is kept pressed downwards by the spring 108 until the pressing member 18 comes into contact with the cap 3, and it can move axially upwards against the action of the spring 18 during further downward movement of the capping head 13. The sleeve 107 in turn is kept pushed downwards by Belleville spring washers 115 arranged between an upper portion, substantially bent inwards at a right angle, of the arms of the clamping bell 101 and the upper face of the shoulder 109. As with known capping heads, the Belleville spring washers 115, which have a load higher than that of the spring 103, intervene only in case of irregularities in the shape of the bottle.
The hollow rod 110 is attached, for example screwed, inside the ejector 106 and in arranged to act as a guide for the pressing member 18 housed within its cavity. A longitudinal slot 113 formed in the lateral surface of the rod 110 acts as a guide for a peg 111 of the ejector 106, which peg can be selectively inserted into one of a plurality of holes 112 vertically aligned on the lateral surface of the guide sleeve 107. The peg 111 has the purpose of preventing the assembly rod 110 - ejector 106 - pressing member 18 to slip off the capping head 13 and, by cooperating with the slot 113, limits the travel of the ejector 106. The selection of the hole 112 determines the extent by which the ejector 106 can protrude downwards from the capping head 13, and thus allows adapting the capping head 13 to various heights of the bottles 2 to be capped. A helical spring 114 arranged inside the cavity of the rod 110, between the ceiling thereof and a shoulder of the outer surface of the pressing member 18, is adapted to keep the pressing member pushed downwards until it comes into contact with the cap 3.
Finally, inside the body 100 and around the guide sleeve 102 for guiding the clamping bell 101, there is provided a further spring 120 intended to remove the load from the clamping bell 101 in order to prevent breakage of the bottle 2 in the event that the capping head moves downward beyond the nominal height of the mouth of the bottle.
The operation of the system is as follows.
When the coordinated rotational movement of the inlet star wheel 11 and the capper 10 brings a bottle 2 and the capping head 13 intended for capping thereof to the slot 17 of the guide plate 16, the capping head 13 starts moving downwards so that the pressing member 18 penetrates through the slot 17 and comes into contact with the cap 3 (Figs. 4, 6). The capping head 13, once it has gone beyond the end of the guide plate 16, can go on moving downwards until it is arranged around the mouth of the bottle 2, and by doing so it causes compression of the spring 114 of the pressing member 18 until said pressing member by moving upwards becomes flush with the ejector 106. A further downward movement of the capping head 13 now causes compression of the spring 108 of the ejector until the ejector comes into contact with the guiding surface provided at the mouth of its guide sleeve 109. In this condition, the ejector 106 and the guide sleeve 109, too, are essentially in contact with the bottle (Fig. 7), and the lower flared portion 121 of the clamping bell 101 interferes with the cam 104 which pushes inwards the arms of the clamping bell, thereby making the teeth 105 push laterally against the cap, thus causing deformation thereof and effecting closure (Fig. 8). It should be noted that, in the condition of Fig. 7, the teeth 105 do not push against the cap 3 yet, although this cannot be appreciated from the drawing.
It should be noted that, because of the height tolerance for the bottles, the travel of the capping head 13 is usually adjusted so as to allow capping also of bottles having a height lower than the nominal height, and it is therefore possible that the head moves further downwards beyond the level required for capping a specific bottle. It is then necessary to prevent the capping head 13 from causing the bottles 2 to explode or break during such further downward movement: this is achieved by the spring 120, which pushes downwards the assembly clamping bell 101 - ejector 106 - pressing member 18, thus relieving the load applied by the springs 103 - 115 - 108 - 114 and consequently reducing the effort exerted by the head 13 on the bottle 2.
It is apparent that the above description has been provided solely by way of nonlimiting example and that variations and modifications are possible without departing from the scope of protection of the invention as defined in the appended claims.
In particular, the guide rod 110 for the pressing member 18 can be omitted and the pressing member can be connected directly to the ejector 106. In this variant, too, one or more pegs can be provided, equivalent to the peg 111, and associated directly with the ejector 106, in order to prevent the assembly ejector 106 - pressing member 18 from slipping off the capping head 13 and limit the travel of the ejector 106. The operation is substantially unchanged with respect to the embodiment shown in Figs. 6-8.

Claims

A system for capping containers (2) by means of caps (3) that can be taken and pulled away from a dispenser (15) by the containers themselves, wherein the containers (2) with the caps (3) applied thereon are conveyed from a cap-taking zone to a capping zone where the caps are clamped onto the containers by corresponding capping heads (13), and wherein, along the path of the containers (2) between the cap-taking zone and the capping zone, a guide plate (16) is provided that is located above the containers (2) at such a height that the caps (3) are kept on the containers (2), said guide plate ending at the capping zone in order to allow the capping heads (13) to perform downward axial movements necessary for capping, wherein said guide plate (16) has a longitudinal slot (17) in an end portion thereof adjacent to the capping zone, characterized in that each capping head (13) is equipped with a pressing member (18) shaped so as to be able to pass through the slot (17) and associated with elastic control means (114) that push said pressing member towards the cap (3) on a container (2) through the slot (17) and keep the pressing member in contact with the cap even beyond the end of the guide plate (16), until capping is completed.
The capping system according to claim 1, wherein the pressing member (18) is mounted inside a hollow guide rod (110) integral for the axial movement with a pushing member (106) intended to cooperate with the pressing member (18) in order to keep a cap (3) pressed against the mouth of the container (2) when the capping head (13) has come into contact with the container, the mounting being such that, because of a downward axial movement of the capping head (13), the pressing member (18), after having come into contact with the cap (3), can axially move upwards in said guiding rod (110) against the action of the control means (114), thereby pushing upwards the guide rod (110) and the pushing member (106).
The capping system according to claim 1, wherein the pressing member (18) is mounted inside an axial cavity of a pushing member (106) intended to cooperate with the pressing member (18) in order to keep a cap (3) pressed against the mouth of the container (2) when the capping head (13) has come into contact with the container, and is integral with said pushing member (106) for an upward axial movement caused by a downward axial movement of the capping head (13) after the pressing member (18) has come into contact with the cap (3).
The capping system according to any of the preceding claims, wherein said longitudinal slot (17) begins before a point where the axis of a container (2) becomes aligned with the axis of the capping head (13) and the capping head (13) starts moving downwards, and ends at the end of the plate (16), where it is open.
The capping system according to any of the preceding claims, wherein the caps (3) preferably are caps with ring (3A) to be pulled for opening.
A method for capping containers (2) by means of caps (3) that can be taken and pulled away from a dispenser (15) by the containers themselves, comprising the steps of:
- conveying the containers (2), after they have taken the caps, from the cap-taking zone to a capping zone where the caps (3) are clamped onto the containers by respective capping heads (13); and

- guiding the containers (2), along the path of the containers (2) between the cap-taking zone and the capping zone, by means of a guide plate (16) that is located above the containers (2) at such a height that the caps (3) are kept on the containers themselves, the guide plate (16) ending at the capping zone in order to allow the capping heads (13) to perform downward axial movements necessary for capping,
wherein the step of guiding the containers (2) is performed by means of a guide plate (16) having a longitudinal slot (17) in an end portion thereof adjacent to the capping zone, characterized in that the method further includes the steps of:
- equipping each capping head (13) with a pressing member (18) intended to engage the cap (3) by passing through the slot (17); and

- controlling the pressing member (18) by means of elastic control means (114) that push the pressing member towards the cap (3) on a container (2) through the slot (17) and keep the pressing member in contact with the cap (3) even after the container has moved beyond the guide plate (16), until capping is completed.
The method according to claim 6, wherein the step of equipping each capping head (13) with a pressing member (18) comprises mounting the pressing member (18) inside a hollow guide rod (110) integral for the axial movement with a pushing member (106) intended to cooperate with the pressing member (18) in order to keep a cap (3) pressed against the mouth of the container (2) when the capping head (13) has come into contact with the container, the mounting being such that the pressing member (18), after having come into contact with the cap (3), can axially move upwards in said guide rod (110) against the action of the control means (114) because of a downward axial movement of the capping head (13).
The method according to claim 6, wherein the step of equipping each capping head (13) with a pressing member (18) comprises mounting the pressing member (18) inside an axial cavity of a pushing member (106) intended to cooperate with the pressing member (18) in order to keep a cap (3) pressed against the mouth of the container (2) when the capping head (13) has come into contact with the container, the mounting being such that the pressing member (18) is integral with said pushing member (106) for the upward axial movement caused by a downward axial movement of the capping head (13), after the pressing member (18) has come into contact with the cap (3).
The method according to any of claims 6 to 8, for capping containers (2) preferably by means of caps (3) with ring (3A) to be pulled for opening.