Patent Description:
More particularly, the invention relates to an apparatus for manufacturing containers for food use.

At present, machines are known which comprise a vacuum pump placed in communication with a chamber inside which a preformed bag, opened on three sides, is usually positioned inside which a food product or any other product is placed to be vacuum-packed.

In such machines of known type, the preformed bag is inserted into the vacuum chamber, after which the air contained in the chamber is sucked, thereby carrying out the vacuum and subsequently, the welding is carried out.

Such machines of known type entail the necessity of having to use preformed bags having a dimension comparable to that of the product.

From <CIT> it is known a packaging device which comprises a vacuum chamber which can be opened to receive a length of at least one single-fold film with the container to be packaged inserted therein, and to close it hermetically thereby producing the vacuum and / or creating an atmosphere with an appropriate gas. In this machine, welding means are provided in the vacuum chamber comprising a concentric arrangement of welding elements in the upper part which operate together with a plurality of lower moulds which alternate in a coaxial position with respect to the upper elements to perform welds in different formats.

From <CIT> it is disclosed a device having upper and lower bells that are vertically displaced between open and closed positions and the lower bell is horizontally displaceable between a welding position and a loading position into which a detachable support plate carrying a number of trays can be removed.

From <CIT> it is disclosed a device to heat seal a tray positioned in a matrix consisting of a frame defined by arms connected together by a movable slide to modify the dimensions of a single compartment delimited by the two longitudinal arms and use the device for sealing different formats of containers or trays.

From <CIT> it is disclosed a heat sealing device adaptable to various formats of containers to be sealed, which device has an upper and a lower bell that are vertically displaced between open and closed positions and a support plate provided with one or more openings for receiving containers which is capable of being removably mounted on the lower bell.

From <CIT> it is disclosed a sealing apparatus for sealing a laminate film onto a container including a bottom housing assembly having a container support for holding a container in place and a drawer which can be pulled out of the bottom assembly via rails to receive a container and then slid back into the bottom assembly to seal the container.

From <CIT> it is disclosed a manual heat-sealing device of containers capable of accommodating containers of different sizes.

Machines of the known type generally have the drawback of making the washing step of the tanks of the lower moulds difficult.

A further drawback has been found in the relative difficulty in varying in a simple and rapid way not only the size of the formats but also the geometric shape of the same.

Therefore, the need is felt to allow the operator who uses the machine to easily clean the moulds and the tank, and the maintenance technician who intervenes to adapt or modify the equipment, to easily replace and overhaul the moulds and the welding means / blades, so that the machine can work with different formats in terms of shape and size, and in greater number with respect to the solutions currently in use.

The present invention aims to overcome the drawbacks of the already known solutions and to propose a machine for manufacturing containers which allows the operator an easy access to cleaning and to the replacement of the lower moulds.

These objects have been achieved by realizing an apparatus for manufacturing containers according to at least one of the appended claims.

A first advantage consists of the fact that easy access to the lower tubs of the sealing station is allowed for the washing operations between processing cycles comprising the sealing of trays of different formats.

A second advantage consists of the possibility to easily change the format of the moulds, both in terms of size and shape.

These and other advantages will be better understood by anyone skilled in the art, from the description below and from the appended drawings, given as non-limiting example, in which:.

With reference to the accompanying drawings, an apparatus for manufacturing containers V with a film F is described.

Depending on the applications, the containers are fed automatically, for example by means of conveyor belts, or manually, to a sealing station <NUM> arranged to seal the containers with a portion of film transiting above the container V, the film being unwound and rewound, for example, by motorized coils <NUM>, <NUM> for feeding and recovery.

In the example described, the film F is a flat film which in use is superimposed on the containers V for the sealing, carried out preferably by thermal welding of the film on the upper outer edge of the container.

However, different films can be used, for example folded or tubular films, for the packaging of containers inserted into two opposing film flaps.

The sealing station further comprising an upper section <NUM> and a lower section <NUM> which can be superimposed on command. The upper section <NUM> is provided with at least one upper sealing profile <NUM>, <NUM>, <NUM>, see <FIG>, and said lower section is provided with a plurality of moulds <NUM>, <NUM>, <NUM> arranged to accommodate at least one container having a selected format, as well as the cutting means of the film once the welding is completed.

Preferably, the superimposing of the upper and lower sections is obtained by means of movements <NUM>, <NUM>, for example actuating cylinders, capable of moving one or both of the sections between a detached position for loading the containers to be sealed and an operative sealing position. Preferably, the superimposing is obtained by means of vertical movement means <NUM>, <NUM> for superimposing at least one upper profile with one of the lower moulds, comprising lifting means <NUM> of a mould of a selected format corresponding to said upper sealing profile.

For example, the vertical movement means may comprise lower actuating cylinders <NUM> arranged to move individually the lower moulds and / or the upper actuating cylinders <NUM> arranged to move the upper section of the sealing station. According to the invention, the lower moulds can be extracted individually and / or collectively from said lower station by means of quick release means comprising, for example, retaining pins <NUM>, which can be inserted and extracted by manual forcing into and from corresponding seats <NUM> provided on said mould.

In the example shown in <FIG>, the retention is exerted by spring balls <NUM> which interfere with the corresponding seats <NUM> of the moulds.

It is however intended that the quick release means of the moulds may be made up of different solutions which do not however provide for the necessary use of mechanical tools. Preferably, the lower moulds are arranged concentrically in each other and the seats <NUM> are provided in respective peripheral rings <NUM> of the moulds, whereas the pins <NUM> are carried by stems <NUM>, possibly connected to a lifting ring <NUM> and operating on each mould independently one from the other being actuated by respective actuators.

<FIG> shows, by way of example, the connection between the stems <NUM> and the ring <NUM> of the inner lower mould <NUM>.

Advantageously, with this solution the operator can easily lift all the moulds and starting, for example, from the small one can extract them and then insert them all, once the lower section has been cleaned, without the need for mechanical tools.

This solution having extractable mobile mould also allows to change the format and type of trays, e.g. square, round or triangular trays.

For these formats it is simply necessary to arrange a mould with a suitable shape and the same must be done with the upper sealing plate.

In case of non-standard format change, that is with "optional" formats, for example round or triangular, the operator simply has to remove the moulds and replace them with the optional ones, remove the sealing plate and replace it with a suitable one.

For this purpose, the upper section <NUM> may be provided with a sealing plate <NUM> provided with a plurality of upper sealing profiles <NUM>, <NUM>, <NUM> corresponding to respective container V formats to be sealed.

In particular, with reference to <FIG>, the sealing plate may be composed of a first fixed plate <NUM> provided with at least one portion <NUM> of an outer sealing profile <NUM> and a second plate <NUM> removable from the fixed plate and provided with one or more internal sealing profiles <NUM>, <NUM>. In the example described, the removable plate comprises a portion <NUM> of the outer sealing profile <NUM> which, when the removable plate <NUM> is inserted inside the fixed plate <NUM>, matches the portion <NUM> and completes the outer profile <NUM>. Advantageously, with this solution it is possible to easily replace at least one welding profile of the upper plate according to the format of the moulds or of the movable mould present in the lower section of the sealing station. In operation, the film F and a container V of a selected format are fed to the sealing station <NUM> with the sections <NUM> and <NUM> in a displaced loading position. Once the container is in the sealing position, the movements <NUM> vertically actuate the lower section <NUM> to bring into a sealing position a container V with the peripheral edge resting on the upper edge <NUM> of the relevant mould preferably provided with a gasket <NUM>.

The movement may continue until the peripheral edge <NUM> of the mould <NUM>-<NUM> is overlapped with the corresponding upper profile <NUM>-<NUM>-<NUM>, with or without an intervention of the movement <NUM> of the upper section <NUM>.

In the example described, the profiles <NUM>-<NUM>-<NUM> are heated profiles which perform a heat-sealing of the film F on the edge <NUM> of the container carried by the mould.

In this case, once heat sealing has been performed, there are therefore provided peripheral blades <NUM>, of known type, which cut the film F along the edge of the mould, which can thus be wound in the recovery coil <NUM> while the sealed container V is moved to an outlet <NUM>, for example a conveyor belt.

In greater detail, and in the embodiment example of the moulds illustrated in <FIG>, due to the superimposing with the profiles <NUM>/<NUM>/<NUM>, the mould <NUM>/<NUM>/<NUM> is lowered with respect to the blade <NUM> against the action of compression springs <NUM> driven by pins <NUM> and interposed between the side wall of the mould and the lower ring <NUM>, until the peripheral cut of the film is performed.

In different embodiments, it is provided that the sealed container V is extracted from the mould by lowering the mould itself or lifting an inner support plate <NUM>, and then removed manually or by mechanical pushers <NUM> which carry the container on an output belt <NUM>.

When the user intends to clean the lower section <NUM>, it will be sufficient to move the sections <NUM> and <NUM> to a displaced position and manually extract the moulds <NUM>-<NUM>, forcing the mechanical resistance of the retaining pins <NUM>.

Moreover, if the format of the moulds is to be changed, by size or shape, it will be sufficient to insert in the section <NUM> moulds of the desired shape and dimensions, remove the upper plate <NUM>, and insert a selected one having the profiles corresponding to the selected formats. <FIG> show in detail, respectively, a top view and a bottom view of a preferred embodiment of the quick release means for the lower moulds.

In this embodiment, the retaining pins are pins <NUM>' which can be inserted and extracted by quick release by means of retaining tabs <NUM> which can be operated, for example manually, between an open release position and a closed engaging position wherein a slot <NUM> of the tab <NUM> engages with a corresponding groove <NUM> integral to the mould and made, for example, by a pin having a T-shaped profile fixed to the mould itself.

With reference to <FIG>, it is disclosed a detail, respectively, in side view in an extracted configuration, in side view in an operative configuration and in perspective view of a preferred embodiment of the means for engaging and extracting the upper welding plate.

In this embodiment, the plate <NUM> is provided with two welding profiles <NUM>/<NUM> and can be extracted from an upper fixed plate <NUM> provided with heating means <NUM>, for example electric resistors, thanks to movement means <NUM> which can be actuated to move the removable plate <NUM> approaching and moving away from the fixed plate <NUM> between a locked operating position and in thermal contact with the fixed plate (<FIG>), for example inside a bell <NUM>' carrying the gasket <NUM>, and a extraction position which is free with respect to the fixed plate (<FIG>) and outside the bell <NUM>'.

Preferably, the movement means comprise stems <NUM> provided with engaging profiles <NUM>, for example T-shaped profiles which can be inserted slidingly into corresponding guides <NUM> of the removable plate <NUM> and which can be actuated by actuators <NUM> (for example oil hydraulic cylinders) to pass between a retracted position corresponding to said operating position of the removable plate <NUM>, preferably with the aid of centring means <NUM>, for example a conical geometric coupling, and a position corresponding to said extraction position of the removable plate, wherein the plate can be easily gripped by an operator and extracted by sliding the profiles <NUM> in the guides <NUM>.

Claim 1:
Apparatus for manufacturing containers (V) with a film (F), comprising:
a sealing station (<NUM>) arranged to seal the containers with a portion of said film and comprising an upper section (<NUM>) and a lower section (<NUM>) which can be superimposed on command, wherein said upper section (<NUM>) is provided with at least one upper sealing profile (<NUM>, <NUM>, <NUM>) and said lower section is provided with at least one mould (<NUM>, <NUM>, <NUM>) removably disposed in said lower sealing station for accommodating at least one container having a selected format of a plurality of formats,
means (<NUM>, <NUM>) for superimposing said at least one upper profile with said at least one lower mould, characterized in that said upper section (<NUM>) is provided with a sealing plate (<NUM>) consisting of a first fixed plate (<NUM>) and a second plate (<NUM>) removable from the fixed plate and provided with at least one upper sealing profile (<NUM>, <NUM>, <NUM>).