DEVICE FOR GRIPPING AND CENTRING BOTTLES FOR CAPPING INSTALLATIONS

Abstract

A device for gripping and centring containers, in particular bottles of which the neck is provided with a rigid collar, in a capping and/or control station of a capping installation is provided and includes a centring ring, intended for being inserted onto a container and for resting on an upper portion of the body of the container, and a plurality of jaws, distributed along the circumference of the centring ring and arranged to receive, in an operating condition, the region of the neck of the container located immediately below the rigid collar. The centring ring is associated with moving members arranged to control a displacement thereof in vertical direction, and the jaws are associated with moving members arranged to control a displacement thereof in vertical direction, simultaneously with or independently of the vertical displacement of the centring ring, and a displacement in horizontal direction. A capping installation is also disclosed.

Claims

1. A device for gripping and centring containers (2) in a capping and/or control station of a capping installation, characterised in that it includes: a centring ring (10), which is intended for being inserted onto a container (2) and for resting on an upper portion of the body (2b) of the container (2) and is associated with moving members arranged to control a displacement thereof in vertical direction, parallel to an axis (A) of the container (2); and a plurality of jaws (12), distributed along the circumference of the centring ring (10) and arranged to engage, in an operating condition, a region of the neck (2a) of the container (2), the jaws (12) being associated with moving members arranged to control a displacement thereof in radial direction, in order to move the jaws from an idle condition, in which they are spaced apart from the neck (2a), to the operating condition, and vice versa.

2. The device as claimed in claim 1, wherein the centring ring (10) and the jaws (12) are associated with moving members arranged to control a simultaneous vertical displacement of the centring ring (10) and the jaws (12).

3. The device as claimed in claim 1, wherein the jaws (12) are uniformly distributed along the circumference of the centring ring (10).

4. The device as claimed in claim 1, wherein the containers (2) have a neck (2a) provided with a rigid collar (3) and wherein, in the operating condition, the jaws (12) are arranged to engage a region of the neck (2a) of the container (2) located immediately below the rigid collar (3).

5. The device as claimed in claim 4, wherein the jaws (12) are equipped with teeth (24) or rubber elements (26) in order to retain the container (2) in the operating condition of the jaws (12).

6. The device as claimed in claim 4, wherein the jaws (12) are equipped with vertical teeth (24) arranged to penetrate into a lower surface of the rigid collar (3) in the operating condition of the jaws (12), or, in the alternative, the jaws are equipped with horizontal teeth (24) or rubber elements (26) arranged to engage, in the operating condition of the jaws (12), the region of the neck (2a) of the container (2) located immediately below the rigid collar (3).

7. An installation for capping containers (2), including at least one capping station having a working head (4) for capping containers (2) and carrying out measurements and/or controls on same and a gripping and centring device (1) as claimed in claim 1.

8. A method of centring containers (2) relative to a working head (4) provided in a capping and/or control station of a capping installation, which station is associated with a gripping and centring device (1) as claimed in claim 1, the method being characterised in that it comprises the steps of: bringing the containers (2), resting onto a supporting plane (30) and arranged with vertical axis (A), to the capping station; lowering the device (1) onto a container (2) to be capped and/or controlled, as far as the centring ring (10) rests on an upper portion of the body (2b) of the container (2); simultaneously moving the jaws (12) in radial direction towards the neck (2a) of the container (2) and bringing them into a first operating position, in which the jaws are in contact with the neck (2a); spacing apart the container (2) from the supporting plane (30) and making the container properly rest against surfaces of the jaws (12); carrying out the operations provided for in the capping and/or control station on the container (2) properly resting against the jaw surfaces, while keeping the container spaced apart from the supporting plane (30).

9. The method as claimed in claim 8, wherein the containers (2) have a neck (2a) provided with a rigid collar (3), and wherein the step of bringing the jaws into a first operating position brings the jaws (12) into engagement with a region of the neck (2a) of a container (2) located immediately below the rigid collar (3) and such that the latter rests onto an upper surface of each jaw (12).

10. The method as claimed in claim 9, wherein: the jaws (12) are equipped with vertical teeth (24) and the step of making the container properly rest against the surfaces of the jaws (12) causes the teeth (24) to penetrate into a lower surface of the rigid collar (3), thereby preventing rotation of the container (2) during the operations carried out in the capping and/or control station; or, in the alternative, the jaws (12) are equipped with horizontal teeth (24) or rubber elements (26) arranged to engage said region of the neck (2a) of the container (2) located immediately below the rigid collar (3) and, after the step of making the container properly rest against the surfaces of the jaws (12), the method includes the step of applying a grasping pressure to the neck (2a) suitable to block the container (2) during the operations carried out in the capping and/or control station.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0029] The above and other features and advantages of the invention will become apparent from the following description of preferred embodiments made by way of non-limiting example with reference to the accompanying drawings, in which:

[0030] FIG. 1 is a top perspective view of the gripping and centring device according to the invention applied onto a bottle;

[0031] FIG. 2 is a view similar to FIG. 1, showing the centring ring only, without the jaws;

[0032] FIG. 3 is an exploded view of the device according to the invention;

[0033] FIGS. 4 and 5 are top views of the device according to the invention, in idle position and in operating position, respectively;

[0034] FIGS. 6a to 6c are top perspective views of some exemplary embodiments of the jaws; and

[0035] FIGS. 7 to 11 are schematic views illustrating some steps of the centring method according to the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0036] Referring to FIGS. 1 to 6, there is shown a device 1 according to the invention for gripping and centring bottles 2, more particularly bottles having a rigid collar (ledge) 3 in the area of neck 2a. Device 1 is associated with a working head 4, shown in FIG. 11, located in a capping and control station of a capping installation for applying for instance screw caps 5 (FIG. 11) to bottles 2.

[0037] Device 1 essentially consists of a centring ring 10 intended to rest against a bottle 2 in the region between neck 2a and body 2b, where bottle 2 widens out and forms an abutment, and of a plurality of jaws 12 (three in the example illustrated), located above ring 10 and preferably equally spaced along the circumference of ring 10.

[0038] The whole device 1 can be vertically displaced, as shown by arrows X, parallel to an axis A (FIGS. 7 to 11) of bottles 2 (axial translation). Moreover, ring 10 and jaws 12 can perform independent axial translational movements and jaws 12 can be horizontally translated relative to ring 10 (radial translation), as shown by arrows Y, from an idle position, shown in FIG. 4, where the jaws are spaced apart from neck 2a of bottle 2, and an operating position, in which jaws 12 engage a region of neck 2a located immediately below rigid collar 3 and the latter rests on the jaws. As it will be better disclosed below, depending on the structure of jaws 12, in the working position, at least in a first step, jaws 12 can engage neck 2a without however applying a grasping pressure.

[0039] Ring 10 has a central hole 14 for the insertion of device 1 onto bottle 2 and is provided with radial arms 16 for connection to suitable members (not shown) controlling the vertical displacement of ring 10.

[0040] Jaws 12 in turn have a body 18 connected to suitable members (not shown) controlling the vertical displacement, which are arranged to enable an axial displacement of jaws 12 jointly with or independently of the displacement of ring 10. Body 18 is mounted on guiding and/or supporting rods 20, in turn connected to members, they too not shown, controlling the horizontal translation.

[0041] The vertical displacement of the whole device 1, the vertical independent displacement of ring 10 and jaws 12 and the horizontal displacement of the jaws can be obtained by means of mechanical, hydraulic or pneumatic devices. Devices of such kind suitable for the purpose are well known to those skilled in the art and are not part of the invention, so that a further description thereof is not necessary.

[0042] Body 18 of each jaw 12 has, in its front part, a recess 22 for receiving neck 2a of bottle 2 during the centring operation. Three jaws ensure the concentricity between neck 2a and head 4. Recess 2 can have different cross-sectional shapes, for instance a triangular shape (as shown in FIG. 6a or 6b) or a circular shape (FIG. 6c).

[0043] In order to engage bottle 2, jaws 12 can be equipped with teeth 24 (FIG. 6a or 6b) or rubber elements 26 (FIG. 6c). Teeth 24 may be horizontal (i.e. radially arranged relative to collar 3), as illustrated in FIG. 6a, in which case they engage the region of neck 2a located immediately below rigid collar 3 (underledge region). In the alternative, teeth 24 may be vertical (axially arranged relative to collar 3), as illustrated in FIG. 6b, in which case they engage the bottom horizontal portion of collar 3. The vertical teeth are used for instance when the plastic in the underledge region is soft: indeed, in such case, horizontal teeth could leave marks that would be tolerated in destructive test, but not in non-destructive tests.

[0044] FIGS. 7 to 11 illustrate various steps of the method according to the invention, in case the jaws are equipped with horizontal teeth or rubber elements.

[0045] FIG. 7 shows that bottle 2 is brought in correspondence of working head 4 (FIG. 11) in a capping station by a conveying unit having a supporting plane, the trace of which is denoted 30, on which bottle 2 rests by means of its base. Of course, in an industrial installation, the conveying unit will successively convey a plurality of bottles 2 to the capping station.

[0046] When the bottle is in position under the working head, the whole device 1 is lowered (FIG. 8), thereby causing ring 10 to rest on the abutment formed by the region connecting neck 2a and body 2b of bottle 2.

[0047] At this point, jaws 12, which until that moment were spaced apart from bottle 2, are radially moved towards neck 2a and are brought to a pre-grasping configuration (FIG. 9), in which they support collar 3 and receive neck 2a in their recess 22, yet still without grasping the neck. In such a pre-grasping configuration, situations in which jaws 12 possibly do not uniformly adhere to bottle 2 can be obviated: indeed, the bottle could be not exactly vertical on supporting plane 30, or off-axis situations could occur due for instance to non-uniform jaws 12 (a jaw is more worn than another one) or to non-uniform radial movements of the jaws.

[0048] Bottle 2 is spaced apart from supporting plane 30 by lifting device 1, as shown in FIG. 10, and an axial force is applied to bottle 2, for instance through a relative translational movement of ring 10 and jaws 12, in order to achieve a correct abutment against the walls of recesses 22 and the top planar surfaces of jaws 12.

[0049] Subsequently, by means of the control systems of jaws 12, a further pressure can be applied against neck 2a in order to tightly grasp it and prevent any rotation of the bottle. At this point, as shown in FIG. 11, working head 4 is brought in contact with the mouth of bottle 2 by means of a roto-translational movement, and the cap application and the other operations required on capped bottle 2 can be performed.

[0050] It is to be appreciated that the grasping step above is not provided for in case of jaws having vertical teeth 24, since the teeth penetrate into the material of collar 3 due to the force applied to achieve the correct abutment of the bottles against the jaw surfaces, and hence the rotation of bottle 2 is already prevented at the end of the pre-grasping step.

[0051] In accordance with a variant embodiment of the invention, the step in which the bottle is spaced apart from the supporting plane can be performed by keeping device 1 stationary and by lowering supporting plane 30.

[0052] The above description shows that the invention enables blocking bottle 2 by means of a grasp applying a force orthogonal to the bottle itself and uniformly distributed around neck 2a, in a manner ensuring concentricity between bottle 2 and working head 4. Blocking therefore takes place without using vertical top loads and without using techniques that could cause torsion of bottle body 2b.

[0053] In this way, it is possible to achieve a same friction level on the bottle region located below collar 3; yet, unlike the known solutions, torsion of cap 5 on the thread during both cap application and cap removal is no longer affected by the top load.

[0054] Of course, during capping, it is necessary to apply to cap 5 the axial load required to bring the warranty band guaranteeing the cap integrity beyond the security references: yet, the force applied by such a load is lower by one order of magnitude than the force applied by the top loads (typically 0.5 to 1 kg instead of 15 to 25 kg), so that the above mentioned drawbacks do not exist.

[0055] Anyway, should the bottle have to be blocked by means of an axial top load, the latter can be applied below the centring device, and hence it does not affect the capping and/or measurement conditions.

[0056] It is clear that the above description is given only by way of non-limiting example and that the construction details and the embodiments can be widely changed with respect to what has been described and shown, without thereby departing from the scope of the invention as defined by the following claims.