WO2020108903A1

WO2020108903A1 - Process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit

Info

Publication number: WO2020108903A1
Application number: PCT/EP2019/079569
Authority: WO
Inventors: Vittorio BELLINI; Gianmaria RABOINI
Original assignee: Gea Procomac S.P.A.
Priority date: 2018-11-28
Filing date: 2019-10-29
Publication date: 2020-06-04
Also published as: IT201800010665A1

Abstract

Process for transferring a container (100) made of thermoplastic material having a rectangular or square bottom (100c) from a withdrawal point (A) of a first rotating unit (200) to a delivering point (B) of a second rotating unit (300), the withdrawal point (A) and the delivering point (B) lying on a same transfer pitch line (P1), comprising the following steps: picking up the container (100) in the withdrawal point (A) by means of a pliers (3) hinged onto a rotary carousel (2) of a transfer star-wheel (1) at a hinge axis (AA); after the container (100) has been picked up, while the rotary carousel (2) keeps on rotating and the pliers (3) moves away from the withdrawal point (A), rotating said pliers (3) relative to its hinge axis (AA) by a predefined angle (a); delivering the container (100) thus rotated to the delivering point (B).

Description

DESCRIPTION

PROCESS FOR TRANSFERRING A CONTAINER MADE OF THERMOPLASTIC MATERIAL HAVING A POLYGONAL BOTTOM, FOR EXAMPLE RECTANGULAR OR SQUARE, FROM A

WITHDRAWAL POINT OF A FIRST ROTATING UNIT TO A DELIVERING POINT OF A SECOND ROTATING UNIT

Technical field

The present invention relates to a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit.

Background art

As is well known, a bottling line is made up of several operating units that carry out a corresponding number of operations on the container, such as sterilization, forming, filling and capping.

In this context, attention is focused on transfer star-wheels for conveying containers positioned between one rotating unit and the other.

Notwithstanding the variants existing in the market, a transfer star-wheel comprises a rotary carousel with compartments spaced equally apart along the outer circumference thereof. Each compartment receives the neck of one of the containers, supporting it by means of a gripper.

In the case of containers with a square or rectangular bottom there arises the problem of the orientation with which incoming containers are received on the infeed side at the transfer star-wheel by the unit located upstream (for example the forming unit) and the orientation with which they are transferred on the outfeed side to the unit located downstream (for example the filling or sterilization unit).

In some known solutions, the transfer star-wheels do not allow the orientation of the containers to be kept under control. In other words, if the containers arrive at the transfer star-wheel with a certain orientation, for example 45°, they are transferred on the outfeed side with the same orientation, or else with an orientation modified in an uncontrolled manner. The orientation of the containers exiting the transfer star-wheel might not be compatible with the unit downstream of the transfer star-wheel. The main problem occurs at the capping or capsuling unit, which needs to receive the containers with a square bottom according to a precise spatial orientation.

Document WO 2017/140330 proposes a transfer star-wheel with collapsible grippers, i.e. grippers that can be released from their fixed position so as to swivel around a hinge axis. However, the jointed structure that allows the gripper to be released and swivel, made up of four levers, is very complex.

JP 2007 098792 A discloses a plurality of grippers, each having a variable direction and distance from the center of the rotary bottle dispenser. The opening/closing direction of each gripper and the distance from the center are controlled by cam grooves. The radial distance of the gripper from the center is also varied.

In this context, the technical task at the basis of the present invention is to propose a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a pick-up point of a first rotating unit to a delivery point of a second rotating unit, which overcomes the above-mentioned drawbacks of the prior art.

Disclosure of the invention

In particular, it is an object of the present invention to provide a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, which enables the orientation of the container on the infeed side to be modified according to the needs on the outfeed side.

Another object of the present invention is to propose a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, which is particularly suitable for transferring containers with a square or rectangular bottom, i.e. having corners.

Another object of the present invention is to propose a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, which can be implemented with a lower structural complexity than the known solutions.

The stated technical task and the specified objects are substantially achieved by a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, said withdrawal point and said delivering point lying on a same ideal circumference or transfer pitch line, comprising the following steps:

- arranging a transfer star-wheel with a rotary carousel between the first rotating unit and the second rotating unit, said transfer star-wheel bearing at least one pliers hinged onto the rotary carousel at a hinge axis, said pliers being provided with two jaws that define a gripping space for the neck of the container, the transfer pitch line being concentric to the rotary carousel;

- picking up the container in the withdrawal point by means of the pliers, the center of the corresponding gripping space defined by the jaws of the pliers lying substantially on the transfer pitch line during the picking up step;

- after having picked up the container, while the rotary carousel keeps on rotating and the pliers moves away from the withdrawal point, rotating said pliers relative to its hinge axis by a predefined angle;

- delivering the container rotated by the predefined angle to the delivering point, the center of the corresponding gripping space lying substantially on the transfer pitch line during the delivering step.

In particular, the rotation of the pliers about the hinge axis is determined by a fixed cam profile.

For example, if the bottom is rectangular or square, the predefined angle is set in such a way that the bottom arrives in the delivering point with two sides parallel to the tangent to the transfer pitch line in the delivering point.

Brief description of drawings

Additional features and advantages of the present invention will become more apparent from the approximate, and thus non-limiting, description of a process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, as illustrated in figure 1 , which shows a top view of a transfer star-wheel used in the process for transferring a container according to the present invention.

Detailed description of preferred embodiments of the invention

With reference to the figure, number 1 indicates a transfer star-wheel for transferring containers 100 made of thermoplastic material, for example PET.

Each container 100 has a tubular body, a threaded neck and a polygonal bottom 100c, for example square or rectangular, or more in general a bottom with corners. In the embodiments described and illustrated herein, the bottom is 100c is square.

The transfer star-wheel 1 is interposed between a first rotating unit 200 (for example a forming unit) and a second rotating unit 300 (for example a filling or sterilization unit).

The transfer star-wheel 1 comprises a rotary carousel 2 bearing a plurality of support stations S for supporting the containers 100 by the neck.

In each support station S there is a pliers 3, which is hinged onto the rotary carousel 2 at a hinge axis AA in such a way as to take on at least: - a first configuration wherein the pliers 3 is fixed, that is, it cannot rotate about its hinge axis AA,

- and a second configuration wherein the pliers 3 can swivel about its hinge axis AA, i.e. it moves freely relative to said hinge axis AA.

Therefore, each pliers 3 is rotatably pivoted to the rotary carousel 2 at its hinge axis AA.

As may be seen from the figure, every pliers 3 comprises two elastically coupled jaws 3a, 3b which define a gripping space for gripping the neck of the container 100 along the outer circumference of the transfer star-wheel 1 .

The process for transferring the container 100 from a withdrawal point A of the first rotating unit 200 to a delivering point B of the second rotating unit 300, according to the present invention, is described below.

First of all, an ideal circumference passing through the withdrawal point A and the delivering point B is defined as the transfer pitch line, indicated as P1. The transfer pitch line P1 is concentric to the rotary carousel 2.

The container 100 is picked up at the withdrawal point A by means of one of the pliers 3 of the rotary carousel 2. During the picking up step, the center of the gripping space of the pliers 3 substantially lies on the transfer pitch line P1.

In particular, the center of the gripping space coincides with the withdrawal point A.

At the withdrawal point A, the container 100 has a random, i.e., uncontrolled, orientation.

After the picking up step, the rotary carousel 2 keeps on rotating, so the pliers 3 with the picked-up container 100 moves away from the withdrawal point A.

In an original manner, the pliers 3 can rotate relative to its hinge axis AA. In particular, the pliers 3 is rotated by a predefined angle a. Said angle is set according to the needs of the second rotating unit 300.

If the bottom 100c is rectangular or square, the predefined angle a is preferably set in such a way that the bottom 100c of the container 100 arrives in the delivering point B with two sides parallel to the tangent to the transfer pitch line P1 in the delivering point B.

On reaching the delivering point B, the container 100 is transferred to the second rotating unit 300, maintaining the orientation that was imposed on it thanks to the rotation of the pliers 3 by the predefined angle a.

During delivery, the center of the gripping space lies substantially on the transfer pitch line P1.

In particular, the center of the gripping space coincides with the delivering point B.

The rotation of the pliers 3 about its hinge axis AA is determined by a fixed cam profile 70.

In the preferred embodiments, the pliers 3 is of the collapsible or bi- collapsible type. Already known configurations of pliers can be used.

The features of the process for transferring a container made of thermoplastic material having a polygonal bottom, for example rectangular or square, from a withdrawal point of a first rotating unit to a delivering point of a second rotating unit, according to the present invention, are clear from the description given, as are the advantages thereof.

In particular, by rotating the pliers during the rotation of the transfer carousel thanks to the cam profile, the orientation of the picked-up container is modified in a controlled manner, and the container is delivered to the downstream unit with the required orientation.

In this manner, no guides are required downstream of the transfer star- wheel, as is instead the case in the prior art solutions.

Claims

1. Process for transferring a container (100) of thermoplastic material having a polygonal bottom (100c), for example rectangular or square, from a withdrawal point (A) of a first rotating unit (200) to a delivering point (B) of a second rotating unit (300), said withdrawal point (A) and said delivering point (B) lying on the same circumference or transfer pitch line (P1 ), comprising the following steps:

arranging a transfer star-wheel (1 ) with a rotary carousel (2) between said first rotating unit (200) and said second rotating unit (300), said transfer star-wheel (1 ) bearing at least one pliers (3) hinged on the rotary carousel (2) at a hinge axis (AA), said pliers (3) being provided with two jaws (3a, 3b) that define a gripping space for the neck of the container (100), the transfer pitch line (P1 ) being concentric to the rotary carousel (2);

picking up the container (100) in the withdrawal point (A) by means of the pliers (3), the center of the corresponding gripping space defined by the jaws (3a, 3b) of the pliers (3) lying substantially on the transfer pitch line (P1 ) during the picking up step;

after having picked up the container (100), while the rotary carousel (2) keeps on rotating and the pliers (3) move away from the withdrawal point (A), rotating said pliers (3) with respect to its hinge axis (AA) of a predefined angle (a);

delivering the container (100) rotated of said predefined angle (a) to said delivering point (B), the center of the corresponding gripping space lying substantially on the transfer pitch line (P1 ) during the delivering step.

2. Process according to claim 1 , wherein said predefined angle (a) is set in such a way that the bottom (100c) of the container (100) arrives in the delivering point (B) with two sides parallel to the tangent to the transfer pitch line (P1 ) in said delivering point (B).

3. Process according to claims 1 or 2, wherein the rotation of the pliers (3) about the hinge axis (AA) is determined by a fixed cam profile (70).