WO2018193485A1

WO2018193485A1 - A filling machine and a process for filling thermoplastic containers

Info

Publication number: WO2018193485A1
Application number: PCT/IT2018/000050
Authority: WO
Inventors: Franco CAPPELLI
Original assignee: Comas S.R.L.
Priority date: 2017-04-21
Filing date: 2018-04-12
Publication date: 2018-10-25
Also published as: IT201700044274A1

Abstract

Filling machine for filling thermoplastic containers united to each other in strips (SC) comprising a conveyor (1) that sequentially supplies the strips (SC) made by the containers (C) open at one side (OC) and oriented with the open side (OC) upward, a filling station (F) for filling said containers where each container (C) receives a predetermined quantity of a substance (M) to be packaged, a preheating station (PH) where the open side (OC) of each container (C) is brought to a predetermined temperature greater than ambient temperature, a welding station (S) where the open side of each container (C) is welded, wherein the strips (SC) are guided on a predetermined path along which the filling station (F) is downstream of the conveyor (1), the preheating station (PH) is downstream of the filling station (F) and the welding station (S) is downstream of the preheating station (PH). The preheating station (PH) comprises a preheating unit (5) connected to respective moving means adapted to move it on said path in such a way that the strips (SC) are subjected to preheating while they are moving between the filling station (F) and welding station (S).

Description

TITLE

A filling machine and a process for filling thermoplastic containers.

DESCRIPTION

The present invention relates to a machine and a process for filling containers made of thermoplastic material.

More particularly, the machine and the process of the present invention concern the filling of containers made of thermoplastic material with liquids, powders, pastes, creams or grains usable in the preparation of food, dietetic, pharmaceutical or cosmetic products, etc.

It is known that a machine for filling containers made of thermoplastic material generally comprises: a station for supplying the containers, which are closed on one side and opened on the opposite side to allow the introduction of pre-established amounts of the substance to be packaged, said containers being joined each other to form "strips", each of them being formed by a predefined number of containers; means for moving the strips along a predefined path between said supply station and a filling station for filling the containers where dispensing means are arranged, which are adapted for introducing simultaneously, in each container of a strip, a predetermined amount of the selected substance; a closing station for closing the containers, in which an operating head is provided which thermally welds the open ends of the containers of each strip; and a system for unloading the filled and welded containers.

The main object of the present invention is to provide a more efficient machine and process for filling containers made of thermoplastic material, both in terms of reduction of the overall cycle time and in terms of reducing the risk of contamination of the product during the phases that follow the filling step.

This result has been achieved, in accordance with the present invention, by adopting the idea of realizing a machine and carrying out a process having the characteristics indicated in the independent claims. Other characteristics of the present invention are the subject of the dependent claims.

Thanks to the present invention, the operations performed by the machine follow an optimized cycle which allows, as previously stated, to reduce both the risk of contamination of the product after filling the containers, and the overall cycle time, with obvious economic and qualitative benefits. Furthermore, a machine according to the present invention has a relatively simple and economical mechanical and functional structure in relation to the advantages it offers. These and further advantages and features of the present invention will be better understood by any person skilled in the art, thanks to the following description and to the attached drawings, provided as an example but not to be considered in a limiting sense, in which:

- Fig.l is a perspective view of a machine according to the present invention;

- Fig. 2 is a further perspective view of a machine according to the present invention;

- Fig.3 schematically represents a strip of empty containers, with an open side for the introduction of the selected substance;

- Fig.4 schematically represents the strip of Fig.3 with the containers filled and closed;

- Fig.5 schematically represents the path followed by the strips in the machine of Fig.l and Fig.2;

- Figs. 6A and 6B schematically represent two operating positions of a turret marked with (4) in the drawings;

- Fig.7 shows a schematic side view of the machine of Fig.l and Fig.2;

- Fig.8 is a schematic side view of a preheating station marked with (PH) in the drawings;

- Figs.9A and 9B show two views in vertical section of the preheating station with the turret (4) attached to a fixed part of the machine (Fig.9A) and respectively to the support arm of the preheating head (Fig.9B);

- Fig.10 is a simplified block diagram relating to a possible control system of the machine working phases.

Reduced to its essential structure and with reference to the figures of the attached drawings, a machine according to the present invention comprises:

- a conveyor or loader (1) that supplies, in sequence, the strips (SC) of the containers (C) open and oriented with the open side (OC) upwards, said conveyor (1) being located between a strips (SC) loading station and a station located downstream where each strip (SC) is introduced into a guide (2) oriented orthogonally to the conveyor (1) with respect to the direction (Dl) from which the strips (SC) come;

- a filling station (F) for filling the containers of each strip (SC) provided with a battery of dispensers, such as syringe dispensers or drop dispensers for powders or grains dispensers, wherein each dispenser introduces a predetermined amount of the selected substance (M) into a corresponding container (C), the filling station (F) being located at a predetermined point above the aforesaid guide (2);

- means for moving the strips (SC) between the conveyor (1) and the filling station (F) acting along said guide (2) to move each strip (SC) along the guide (2) between the exit point of the loader (1) and the filling station (F);

- a preheating station (PH), downstream of the filling station (F), in which the open side (OC) of each strip container (SC) is preheated to a predetermined preheating temperature by means of respective preheating means which are activated at the arrival of each strip (SC) in the preheating station (PH);

- a welding station (S), downstream of the preheating station (PH), in which welding clamps are arranged and acting, wherein said welding clamps, when in contact with the open and preheated side of the containers (C) of each strip (SC), bring said open side to a second predetermined temperature, higher than the preheating temperature, and close said sides determining their welding;

- means for moving the strips (SC) between the preheating station (PH) and the welding station (S);

- means for moving the filled and welded strips, acting along a respective exit guide (3).

The conveyor or loader (1) for feeding the strips (SC), the means for moving the strips (SC) between the end point of the loader (1) and the filling station (F), the clamps of the welding station (S) and the respective control mechanisms, the means for moving the strips (SC) between the preheating station (PH) and the welding station (S), and the means for removing the welded strips from the welding station (S) are known to skilled in the art and therefore will not be described in greater detail. The aforementioned means are positioned on a base structure (BA) which also houses actuators and service systems for actuating and controlling these known means. The containers (C) are made of thermoplastic material known per se.

With reference to the embodiment shown in the accompanying drawings, the path followed by each strip (SC) comprises a first section (Dl) corresponding to the loader (1), a second section (D2) orthogonal to the first one and comprised between the end point of the loader (1) and the filling station (F), a third section (D3) which is the continuation of the second section and is defined on the turret (4) described below, and a fourth section (D4), placed between turret (4) and the discharge of the welded strips downstream of the welding station (S), orthogonal to the third section (D3). In this example, therefore, the path of the strips (SC) is in the shape of a "U", with the section (Dl) forming a first branch of the "U", the sections (D2) and (D3) that together form a second branch, and the section (D3) forming the third branch. According to the present invention, in the preheating station (SH) a turret (4) is arranged with a vertical axis on which a cross-shaped guide is formed with two orthogonal guide arms (4A, 4B) each of which is suitable for housing a strip (SC) coming from the filling station (F). Each arm (4A, 4B) is delimited by two opposite vertical walls between which a strip (SC) coming from the filling station (F) can translate. The rotation of the turret (4) determines the corresponding rotation of the anus (4A, 4B) which, consequently, can be positioned in line with the aforesaid guide (2) along which the strips (SC) moving from the filling station (F) and respectively orthogonally to the same guide (2).

In the schematic diagram of Fig.6A, the arm (4A) is aligned with the guide (2), while the arm (4B) is orthogonal to the latter. In Fig.6B the turret (4) has been rotated by 90°, so that the arm (4B) is aligned with the guide (2), while the arm (4A) is orthogonal to the latter. In this way, each time the turret (4) rotates 90°, one of its arms (4A, 4B) is aligned with the guide (2) while the other arm is oriented towards the welding station (S).

The following describes a possible mode of implementation of the aforesaid rotary movement of the turret (4) around the relative axis (y).

The preheating station (PH) is in correspondence of the turret (4). With reference to the example shown in the attached drawings, the preheating station (PH) comprises a heating head (5) mounted on a support controlled by a vertical axis actuator (50). In this way, the heating head (5) can be moved vertically from and towards the turret (4) and can rotate integrally with the latter under the control of the rotary actuator (40). For example, the heating head (5) comprises a battery of nozzles (56) for supplying air at a predetermined preheating temperature to the containers forming the strips (SC). The reference (57) in the drawings indicates the pipes that supply hot air to the nozzles (56). Alternatively, for example, the heating head may be an infrared radiant head. It is understood, however, that the heating head (5) can generate heat in any suitable manner.

In accordance with a possible embodiment of the present invention and with reference to the attached drawings, the preheating head (5) is controlled by a vertical actuator (50) which, as previously said, allows its movement (5M) to and from the underlying turret (4). The actuator (50) is mounted on an arm (51) that is rotatably connected to a fixed part of the machine so that it can rotate about a corresponding vertical axis (51V) coinciding with the axis (y) of the turret (4). The rotation of the arm (51) around the axis (51V), and consequently the rotation of the preheating head (5) around the same axis, is controlled by a pneumatic actuator with horizontal axis (52) located in the structure (BA) under its upper plane (P). The actuator (52) is connected to the arm (51) by means of a lever (53) which, in turn, is connected to a vertical shaft (54) whose axis coincides with the rotation axis (51V) and on which it is fixed the arm (51). Therefore, by actuating the actuator (52), the arm (51) is rotated, and, consequently, the heating head (5) rotates around the vertical axis (51V). The shaft (54) passes inside a fixed tubular body (55) positioned under the turret (4) in the base of the machine. The turret

(4) is alternately linked to the fixed structure of the machine or to the preheating head

(5) . For example, this can be achieved by providing two pneumatic shutters (40, 41) designed to engage two corresponding cavities (40C, 41C) provided on the lower side of the turret (4). The first shutter (40) is integral with the upper base of the tubular body (55). The second shutter (41) is integral with the arm (51) on which is mounted the actuator (50) that vertically moves the preheating head (5). The shutters (40, 41) constrain the turret (4) alternatively to the fixed structure of the machine and to the preheating head (5).

A possible work cycle of the machine described above is as follows.

Once filled, a strip (SC) coming from the filling station (F) is moved into the arm (4A) of the turret (4), after which the heating head (5) is lowered towards the strip (SC) thus preheating the open side (CO) of the respective containers (C). During this preheating, the turret (4) is made integral with the heating head (5) by actuating the shutter (41) which engages the lower cavity (41C) of the turret. Then, the head (5)/turret (4) assembly is rotated by 90° so that the arm (4A) and the strip (SC) are aligned along the direction (D4). Thereafter, the turret (4) is released from the arm (51) of the heating head (5) and is constrained to the fixed structure of the machine by actuating the shutter (40) which engages the lower cavity (40C) of the turret. The heating head (5) is raised and brought back to the starting position, while the preheated strip is transferred to the welding station (S) where the edges of the open side (CO) of each container of the strip are welded thus providing the final closure of the containers themselves. When the strip leaves the preheating station (PH), the turret (4) has the other arm (4B) already in a position suitable to receive another strip (SC) coming from the filling station (F). It goes without saying that following the rotation of the turret (4) the aforementioned cavities (40C, 41C) exchange their places. Fig.4 schematically shows the strip formed by the filled containers and with the welded upper side indicated by the reference "CC".

Characteristically, the preheating of the containers takes place during the phase of moving them from the filling station (F) to the welding station (S).

The provision of a rotating turret (4) for keeping the strips (SC) in position in the preheating station and the provision of a rotating preheating head (5) also allows, in particular, to carry out the process described above in a machine which involves the movement of the strips along a path in which the filling station (F) and the welding station (S) are on two different branches of the path, i.e. on two branches not aligned along the same direction.

In the example described above, the preheating station (PH) is a mobile station and, more particularly, is a station rotating about a vertical axis (y; 51V) to allow a reduction of the overall cycle time and a lower exposure of the substance (M) to the risk of contamination.

Preferably, the preheating temperature is lower than the welding temperature.

The various work steps of the machine are controlled by a programmable unit (UE) known per se to the industrial automation technicians and that controls the actuators (50) and (52), the activation of the heating head (5), the activation of the dispensers provided in the filling station (F), the conveyor or loader (1), the shutters (40) and (41), the clamps (PS) of the welding station (S) and the sensors (D) that detect the presence of strips (SC) along the path followed by the strips, as schematically shown in Fig.10.

In practice, the details of execution may in any case vary in an equivalent manner as regards the elements described and illustrated without departing from the scope of the solution idea adopted and therefore remaining within the limits of the protection granted by the present patent.

Claims

1) A filling machine for filling thermoplastic containers united to each other in strips (SC) comprising a conveyor (1) that sequentially supplies the strips (SC) made by the containers (C) open at one side (OC) and oriented with the open side (OC) upward, a filling station (F) for filling said containers where each container (C) receives a predetermined quantity of a substance (M) to be packaged, a preheating station (PH) where the open side (OC) of each container (C) is brought to a predetermined temperature greater than ambient temperature, a welding station (S) where the open side of each container (C) is welded, wherein the strips (SC) are guided on a predetermined path along which the filling station (F) is downstream of the conveyor (1), the preheating station (PH) is downstream of the filling station (F) and the welding station (S) is downstream of the preheating station (PH), characterized in that said preheating station (PH) comprises a preheating unit (5) connected to respective moving means adapted to move it on said path in such a way that the strips (SC) are subjected to preheating while they are moving between the filling station (F) and welding station (S).

2) Machine according to claim 1 , characterized in that said preheating unit (5) is mounted on a respective supporting arm (51) that, in tum, is secured to a shaft (54) controlled by a corresponding actuator (52) that determines its rotation around a vertical axis (51V).

3) Machine according to claim 1 characterized in that said preheating unit (5) is connected to an actuator (50) that provokes the vertical movement thereof from and to the path followed by the strips (SC).

4) Machine according to claims 1-3, characterized in that the actuator (50) that moves vertically the preheating unit (5) is mounted on said supporting arm (51).

5) Machine according to claim 1 characterized in that in said preheating station is arranged a rotatable turret (4) that is rotatable about a respective vertical axis (y), on which turret two orthogonal guides (4A, 4B) are formed to keep the strips (SC) in a suitable preheating position.

6) Machine according to claims 1 -5 characterized in that the axis (y) of the turret (4) coincides with the rotation axis (51V) of the arm (51) supporting the preheating unit (5).

7) Machine according to claims 1-6 characterized in that the turret (4) is alternatively constrained to the heating unit (5) or to a fixed structure of the machine. 8) A process for filling thermoplastic containers grouped in strips (SC), comprising sequential feeding of the strips (SC) of containers (C) having an open side (OC) and oriented with the open side (OC) upward by means of a conveyer (1), the passage of the strips (SC) through a filling station (F) where each container (C) receives a predetermined amount of a substance (M) to be packaged, the passage of the strips ( SC) through a preheating station (PH) where the open side (OC) of each container (C) is brought to a predetermined temperature higher than the ambient temperature and the passage of the strips (SC) through a welding station (S) where the open side of each container (C) is welded, wherein the strips (SC) are guided on a predetermined path along which the filling station (F) is downstream of the conveyer (1), the preheating station (PH) comprises a preheating unit (5) and is downstream of the filling station ( F) and the welding station (S) is downstream of the preheating station (PH), characterized in that in said preheating station (PH) the strips (SC) are subjected to preheating while they move between the filling station (F) and the welding station (S), and the preheating station (PH) is moved along the path followed by the strips (SC) between the filling station (F) and the welding station (S).

9) Process according to claim 8, characterized in that the preheating station (PH) rotates about a vertical axis along with the strips (SC) and the preheating unit (5).

10) Process according to claims 8-9 characterized in that in said preheating station (PH) the strips (SC) are on a rotatable supporting turret (4).