Abstract: Methods and apparatus for introducing a modified atmosphere into a package and sealing that package with a film are disclosed. Cooperating upper and lower bell members having internal volumes in fluid communication with one another via a duct configured to cause sequential pressure differentials between the volumes permit the sealing film to be controllably retracted from and applied to outflow holes so as to allow evacuation of ambient air using a single constant vacuum source, rather than requiring precision timing controls and/or multiple vacuum sources. Another dedicate circuit introduces the modified atmosphere into the package, and a sealing unit such as a heat welder subsequently seals the film against the package.

Abstract: Apparatus with facing bell members for modified-atmosphere packaging of products contained in trays, comprising at least three circuits: a first circuit and a second circuit (24, 25) which are connected to the main chamber (P) enclosing the internal volume of the trays and open out in different positions (23, 23?) of this volume and a third circuit (17) connected to the internal chambers (2, 9) of the bell members (1, 8) and these circuits are intercepted by respective valve means (28, 128, 18, 118) so as to be initially all connected to the vacuum means (21, 121) and then the said first circuit (24) is closed, while the said second circuit (25) is connected to the means (26) for introducing the service gases which, entering into the tray, force the remaining air out so as to occupy a small buffer formed by the said second closed circuit (24, 28).

Abstract: A device for spreading the tray sealing film in so-called tray sealers, in order to avoid the formation of folds in said film which, with the trays, is inserted in a sealing and cutting station, between a pair of opposing bells provided with a relative reciprocal approaching and distancing movement, where downstream of said station means are provided to subject the off-cut of film which exits to a transversal stretching action which ensures correct spreading of said film between said bells, characterized by comprising means for braking the film upstream of said station and comprising pincer means with a jaw mounted on the side of the upper bell from which the film exits, turned downwards and vertically opposing a corresponding jaw mounted on the lower bell, all being envisaged to ensure that in the reciprocal approach and closure step of the two bells, before the film is gripped and blocked between them, longitudinal and lateral portions of the film which are close to the bells are pincered between said oppos

Abstract: Machine for packaging products with stretch film the flaps of which are stretched, folded and mutually superimposed on the bottom of the product usually arranged in a tray, comprising a final station with a motorized heat-sealing conveyor to mutually secure said flaps with a heat-sealing operation, characterised in that this final heat-sealing station is provided with an upper protective chamber for the operator, and which limits the loss into the work environment of heat produced by said heat-sealing conveyor, now incorporated in this protective chamber, which has a shape and size such as to allow the packaged products to be conveyed therethrough without interference, this protective chamber being provided with an inlet opening usually communicating with the casing of the packaging machine and being provided with an outlet opening for conveying the packaged products, wherein at least this last outlet opening is closed by a swinging barrier that prevents loss of heat towards the outside and that is arranged t

Abstract: When the opposing housings (1, 8) of the apparatus are closed, they form between them a small main chamber (P) delimited above by the film (H) for covering the tray and below by the tray (V) itself containing the product (M), and laterally by any suitable mechanical interface structure which surrounds the perimeter of said film and connects it to the perimeter of the upper edge (B) of the tray, this interface structure having holes (22) which are suitably distributed, are located outside the perimeter of the tray, and communicate with said main chamber (P). One or more of these holes (22) open(s) on at least one side of the tray and is/are connected to a first circuit (23, 24), while another one or more of said holes (22?) open(s) on at least one opposing side of the tray and is/are connected to a second circuit (17) which in turn is connected to the inner chambers of the two housings (1, 8).

Abstract: The external conveyor supplying the trays coming from the filling machine is connected to a conveyor formed of parallel straps or belts, which has a greater length than the length of the group of trays of larger dimensions to be grouped together and which is provided in the end part with components inserted between the belts, a comb lifter of a length correlated with the length of said tray group to be formed, connected to lifting and lowering means with suitable acceleration and deceleration ramps. Upstream of the lifter, sensors are provided which detect the position in space of the trays arriving from the external conveyor in succession. A processing and control unit is provided to process the information arriving from said sensors.

Abstract: Apparatus for the mechanized replacement of the sealing and cutting modules in the sealing station of machines for the packaging of products in trays, with said station comprising a lower mold with seats for the support of the edges of the trays with product and that by way of motion means is cyclically raised and lowered vertically with respect to an upper mold which supports in the lower part said modules by way of hooking and releasing means so that said modules can be removed and replaced in a selective manner, characterized in that said hooking and releasing means of the modules are provided between the upper plate of each module and the respective hooking plate of the upper mold, with complementary mechanical engaging means of such a kind and oriented so as to be coupled and uncoupled individually and/or simultaneously, imparting to each said module an approaching and separating vertical movement with respect to said hooking plate of the upper mold.

Abstract: Between the two housings each having a recess and below and parallel to the film, there is provided a frame having openings greater in plain view than the underlying trays to be packaged, supported such that, during the closure of the housings the frame interacts with seal and contributes to the formation of a main chamber delimited by the upper edge of the tray and by the film above this edge. Air is removed from these recesses to form the desired level of vacuum therein, while, in the main chamber is isolated from the recesses of the two housings, so that the process gases can be injected directly into the main chamber, while a corresponding quantity of atmospheric air is directed into the recesses to balance the pressures on the opposite faces of the film When the process gases have been fed in, the film is welded to the edge of the tray and is cut outside this edge.

Abstract: Apparatus with facing bell members, for modified-atmosphere packaging of products placed in trays, which comprises means for the cyclic positioning of an extended portion of bather film between the said two open bell members and over trays housed with gasket means in the seats of the bottom bell member, which comprises means for moving the said bell members towards each other so as to close between them the said film and to close under and at a suitable distance from this latter the edge of the tray, apparatus of the type that when the bell members are closed, they form therein two volumes not directly communicating, one of which is formed by the internal chambers of the same bell members that communicate with each other via circuits, for example peripheral, while the other volume is formed by the main chambers of the trays with the product, wherein the said chambers are connected with a portion of their perimeter to holes and to a dedicated circuit for the controlled introduction of process gases and are con

Abstract: A device for spreading the tray sealing film in so-called tray sealers, in order to avoid the formation of folds in said film (F) which, with the trays, is inserted in a sealing and cutting station (S), between a pair of opposing bells (T1, T2) provided with a relative reciprocal approaching and distancing movement, where downstream of said station (S) means are provided to subject the off-cut of film which exits to a transversal stretching action which ensures correct spreading of said film between said bells, characterized by comprising means for braking the film upstream of said station (S) and comprising pincer means (P, P?) with a jaw (1, 1?) mounted on the side of the upper bell (T2) from which the film exits, turned downwards and vertically opposing a corresponding jaw (2, 2?) mounted on the lower bell (T1), all being envisaged to ensure that in the reciprocal approach and closure step of the two bells (T1, T2), before the film is gripped and blocked between them, longitudinal and lateral portions of t

Abstract: The external conveyor supplying the trays coming from the filling machine is connected to a conveyor (1) formed of parallel straps or belts (101), which has a greater length than the length of the group of trays of larger dimensions to be grouped together and which is provided in the end part with components inserted between the belts (101), a comb lifter (9) of a length correlated with the length of said tray group to be formed, connected to lifting and lowering means with suitable acceleration and deceleration ramps.

Abstract: Apparatus with facing bell members for modified-atmosphere packaging of products contained in trays, comprising at least three circuits: a first circuit and a second circuit (24, 25) which are connected to the main chamber (P) enclosing the internal volume of the trays and open out in different positions (23, 23?) of this volume and a third circuit (17) connected to the internal chambers (2, 9) of the bell members (1, 8) and these circuits are intercepted by respective valve means (28, 128, 18, 118) so as to be initially all connected to the vacuum means (21, 121) and then the said first circuit (24) is closed, while the said second circuit (25) is connected to the means (26) for introducing the service gases which, entering into the tray, force the remaining air out so as to occupy a small buffer formed by the said second closed circuit (24, 28).

Abstract: When the opposing housings (1, 8) of the apparatus are closed, they form between them a small main chamber (P) delimited above by the film (H) for covering the tray and below by the tray (V) itself containing the product (M), and laterally by any suitable mechanical interface structure which surrounds the perimeter of said film and connects it to the perimeter of the upper edge (B) of the tray, this interface structure having holes (22) which are suitably distributed, are located outside the perimeter of the tray, and communicate with said main chamber (P). One or more of these holes (22) open(s) on at least one side of the tray and is/are connected to a first circuit (23, 24), while another one or more of said holes (22?) open(s) on at least one opposing side of the tray and is/are connected to a second circuit (17) which in turn is connected to the inner chambers of the two housings (1, 8).

Abstract: Between the two housings (1, 18), and below and parallel to the film (F), there is provided a frame (7) having openings (8) with shapes and dimensions suitably greater than the shapes and dimensions in plan view of the underlying trays (V) to be packaged, supported by any means such that, during the closure of the housings (1, 18), this frame (7) interacts with sealing means and contributes to the formation of a main chamber (29) delimited by the upper edge of the tray and by the film above this edge, which is initially connected to the inner chambers (19, 2, 102) of the two housings (1, 18), to enable the air to be removed from these chambers and to form the desired level of vacuum therein, while, in the next step, said main chamber (29) is isolated from the inner chambers of the two housings, so that the process gases for preserving the product can be injected directly into this main chamber, while a corresponding quantity of atmospheric air is directed into said inner chambers of the housings (1, 18) to co