MXPA97003878A - Apparatus to remove and process thermoformed objects from a thermoforming machine - Google Patents

Abstract

The present invention relates to apparatus for extracting and processing thermoformed objects from a thermoforming machine, comprising at least one station for processing thermoformed objects produced in the thermoforming machine, the apparatus is arranged in sequence immediately below the thermoforming machine and upstream of a stacking station for the thermoformed objects, the apparatus includes at least one extraction plate, which moves synchronized with the thermoforming machine between a position in which it collects a multiplicity of thermoformed objects by the thermoforming machine , and the at least one processing station and holds them securely thereto during each processing operation, a rigid support arm with one end of at least one extraction plate, a carriage or sliding means, which is connected to another end of the support arm, c arro or sliding means, and driving means for the carriage or sliding means acting synchronized with an operation cycle of the thermoforming machine

Description

APPARATUS TO REMOVE AND PROCESS THERMOFORMED OBJECTS FROM A THERMOFORMING MACHINE DESCRIPTION This invention relates to an apparatus for removing or removing and processing thermoformed objects in a mold of a thermoforming machine from a sheet of thermoformable material. The extraction of groups of thermoformed objects from the female die of a thermoforming machine or press, through the use of a suction plate that is inserted between the male die and the female die during the step of opening the mold, removes the objects from the mold. mold, usually the female die, and transfers them away from the thermoforming machine, as described, for example, in Italian Patent Applications nos. 1 175 178 and 1 218 634, or supplies them to a template conveyor belt on which the objects are subjected to a number of processing steps or handling procedures, see Italian Patent Application VR 92A000092, has already been suggested. In the case of objects which are thermoformed from a fast cooling sheet material, the time required for the removal of the objects from the mold and for their transfer to a processing or handling station, such as a beading station, may be excessive , in the sense that it will allow the objects to cool down below a threshold above which the material can be easily and reliably worked. This applies, for example, to glass polystyrene, which becomes vitreous rapidly after thermoforming, and, therefore, it is important that any subsequent processing of tersoring, in particular beading of objects such as vessels, vessels , cups and the like, which involve the plastic formation of the edges of these objects, is quickly introduced, but this also applies to other types of processing such as perforation, labeling, sterilization and the like, with the exception of stacking. In addition to the aforementioned advantages for materials, which stabilize rapidly after thermoforming, working on thermoformed objects before they are cooled below the working threshold could also be advantageous for other thermoformable materials, such as co-extruded materials. , polypropylene, polyesters, polyethylene and others, which takes advantage of a great ease of processing, thus ensuring a longer life of the tools used.

The main object of this invention is to provide an extraction or removal and processing apparatus through which a group of thermoformed objects can be removed from between the male and female dies of a thermoforming machine in order that they can be carried out one or more procedures on them during one or more operation cycles of the thermoforming machine immediately after these objects have been removed. Another object of this invention is that such extraction and processing apparatus must be designed to serve as a thermoforming machine with a female die, which is located either above or below the male die. A further object of this invention is to provide an extraction and processing apparatus of high reliability and productivity. These and other objects, which will be apparent below, are achieved through an extraction and processing apparatus for thermoformed objects of a thermoforming machine, such apparatus comprising an extraction plate designed to move synchronously with the thermoforming machine between a position of withdrawal, wherein a group of thermoformed objects are removed when the thermoforming machine is in the position where the dice are open and at least one station for processing or handling such objects during the remaining part of one or more of the complete cycles of the thermoforming machine. Advantageously, the station or each of the work stations, comprise a beading unit of any suitable type that is arranged to flange the objects, which continue to retain the heat when they are supported by the extraction plate. Other objects and advantages of this invention will be more apparent from the following detailed description of some of its modalities, which are given only by way of non-limiting examples with reference to the accompanying drawings, in which: Figure 1 is a Diagrammatic view in lateral elevation with parts in cross section of a thermoforming machine and a withdrawal apparatus for the extraction and processing of thermoformed objects that serve the thermoforming machine and which have in their extraction plate, which is moved to a unit for processing the group of thermoformed objects, which have just been removed from the thermoforming machine, Figure 2 shows a detail of Figure 1 at an enlarged scale, Figure 3 illustrates a view similar to that of Figure 1 , while the thermoforming machine carries out the remaining part of its work cycle, that is, the thermoforming of a group successively of objects, while the extraction and processing apparatus cooperates to perform the processing of the objects of the immediately preceding group of objects, FIG. 4 shows a detail of FIG. 3 in cross-section and on an enlarged scale, FIG. illustrates a diagrammatic side elevation view with cross-sectional portions of the start of a new work cycle, both of the thermoforming machine and of the extraction and processing apparatus it serves, Figure 6 is a diagrammatic side elevational view with cross-sectional parts illustrating another embodiment of the extraction and processing apparatus serving a thermoforming machine, comprising two successive stations for processing the groups of objects, while being supported and transported by an extraction plate that removes them of the thermoforming machine, Figures 7, 8 and 9 are views similar to here Fig. 6, which illustrate the various successive steps in processing a group of objects supported and transported by an extraction plate, which removes them from the thermoforming machine, Fig. 10 is a diagrammatic view from above of a thermoforming machine and the extraction and processing apparatus for groups of objects, which is provided with a pair of plates for removing, supporting and transporting objects, which are designed to operate in an alternating manner, Figure 11 shows a cross-sectional view and on an enlarged scale of a thermoformed object, coupled with a former on an extraction suction plate on which the object can be flanged, Figure 12 is a view similar to that of Figure 11, which illustrates a corresponding former provided with an elastic retaining ring acting on the inner surface of the object, Figure 13 is a similar view. Figure 12 illustrates a former provided with suction means for holding a thermoformed object, and Figure 14 shows a cross-sectional view of the thermoformed object holding an extraction plate in place by means of retention, which act on the external surface of the object so that a drilling operation can be performed on its base. In the Figures, of the accompanying drawings, the identical or similar parts or components have been identified through the same reference numbers. Referring first to the entire embodiment illustrated in Figures 1 to 5, it should be noted that an extraction and processing apparatus, generally indicated with 1, for objects 2 (generally hollow containers with a solid bottom such as containers, trays, cups, coffee cups and the like), which have been thermoformed in a thermoforming machine or press 3 comprising an extraction plate 4, which is arranged to move synchronously with the thermoforming machine 3 between a position of withdrawal, wherein it removes a group of thermoformed objects 2 when the thermoforming machine 3 is in the position where its dice are open (Figures 1 and 5) and a processing station 5, in which the whole group is processed or handled (Figures 1 and 2), during the remaining part of a complete cycle of the thermoforming machine 4 served by, or cooperating with the extraction plate 1. The thermoforming machine 3 is a press that has either an individual female die or double 6a, which is, for example, located in the lower position, as is well known in the art, and a corresponding upper male die 6b, at least one of which is supported so that it can move vertically so that the two dice can move together to a closed position and separate cyclically to a position where they remain open. The female die or dice 6a are provided with a plurality of depressions 7, which are axially aligned with a respective obturator 8, which is axially and movably supported within the male die 6b and designed to enter a depression 7, when the mold closes (Figure 3). The shutters 8, each one is supported by a respective vertical control bar 9, which is connected in the upper part to a control frame 10 through one or more drive units, each comprising, for example, a linear actuator. , such as a piston operated by fluid and a cylinder unit 11. Each depression 7 in the female die or dice 6a is also provided with a corresponding extractor / elevator 12, which is operated, for example together with the others through a frame 13 by a suitable linear actuator 14, which is designed to lift a thermoformed object 2, formed therein above the corresponding depression 7, while the mold is opening (Figure 1).

Along the dies 6a and 6b there is a pair of longitudinal members 15 of a feeder / conveyor, for example, of the chain type, which is designed to feed a sheet of the thermoformable material 16, from which the waste 17 after each molding, it is moved upwardly for removal from the press 3. The extraction plate 4 can be of any suitable type, for example, as described in the Italian patent application VR94A000082, filed on 14/09 1994, in the name of the applicant, using either a negative pressure retention effect on objects 2 of each molding or mechanical securing means. More particularly, the extraction plate 4 is supported, for example, in a cantilever shape, at one end of a support arm or arms 18, the other end of which is connected to, or integral with, a carriage or slide 19 mounted with the purpose of sliding or rolling on guide means, generally indicated by 20, for example, of the frame type controlled by a motor / reduction gear unit 21, which is designed to impart a cyclic movement from back to front, synchronously with the operation cycle of the press 3, between the withdrawal position, when the dice 6a and 6b are opened, and a work station 5, which is located in a position adjacent to the press. The work station 5 comprises a beading unit of any type suitable for flanging objects 2 of a mold, which remain hot from the press, while they are still supported by the extraction plate 4. At this point, the work 4 has a plurality of seats 22, which receive and support the bottom of each object 2 of a mold, which are picked up by the extraction plate 4. Each receiving seat 22 is supported at one end by a respective bar 23 , the various bars 23 in seats 22 have their other ends fixed to a common frame 24 controlled by a linear actuator, such as, for example, a piston operated through fluid and a cylinder unit 25, which is designed to move them. between an extended position and a retirement position. An annular member 26, one of its front ends has an annular curly shape or contour 27 (Figure 4), is longitudinally movable coaxially about the axis of each receiving seat 22 and the other end of the annular member 26 is fixed to a plate of support 28, which has, in a position corresponding to each receiving seat, a through hole 29 of diameter so as to allow free passage through the respective seat 22. The face of the support plate 28, which gives in front of frame 24, it is connected to one or more suitable linear actuators, for example, a pair of fluid operated pistons and cylinder units 30 supported by a support structure indicated generally by 31, which also mounts a fluid operated unit 25. The support structure 31 can be, at the same time, rotated 90 ° about an axis 32 perpendicular to the direction of the axes of the bars 23 through the action of a unit 33. of motor gear / reduction (Figure 5). The appropriate flange formers 34, each of which is inserted into an annular rim forming or forming 27, which is provided on the face of the extraction plate 4, which faces the female die 6a and therefore the work station 5 These are first designed so that all are engaged to the inner surface of the rim of a respective object 2 removed from the female die 6a when the plate 4 is in the extraction position and subsequently cooperates with a corresponding annular member 26, which is pushed against these units operated with fluid 30 to form the flanged rim or edge of the object in the work station 5. To counter the thrust of the units operated with fluid 30, the extraction plate 4 lies along the entire length, for example, of a carriage 35 in the work station 5, and this carriage, although overcoming the thrust during the step of flanging or edges, does not constitute any obstacle in the path of the extraction plate 4 between the position of ex traction and work station 5. The operation sequence of the extraction means described above is quite simple. During the stage, when the dice 6a and 6b are opened, the extractors 12 release the objects 2 from a mold of the corresponding depressions 7 in the female die, while the extraction plate 4 starts its trajectory towards the extraction position (Fig. 5) . When the press is fully open, the objects 2 have already been inserted on a corresponding edge former 34, and are transported to the work station 5, while at the same time, the waste 17 is removed and the press begins to close ( Figure 1) . The units operated with fluid 25 and 30 are driven in the work station 5 to move the seats 22 against the bases of the objects 2, so that each object is seated deep on its corresponding former 34 and for pushing annular members 26 along the objects, in such a way that the formers 27 meet and lie around the outer edge of the objects 2, which are secured through the corresponding formers 34 to act together with the latter in order to flange the edge by deformation of plastic with heat, making use of the heat work of the thermoplastic material from which the objects are made and taking advantage of the heat of residual thermoforming that remains retained in an appreciable amount (and in any case well above the thermal work threshold) in the objects 2, while the same objects are safely held to the extraction plate 4 in the same space or mutual arrangement as in the female die 6a (Figure 3). Once the flange operation is completed, the objects 2 are released from the extraction plate 4, for example through a respective jet of air or through any other suitable release means, and are picked up by the reception seats. 22, and then through the action of the unit operated with fluid 25 are removed from the extraction plate together with the annular members 26, through the actuation of the units operated with fluid 30 and following the rotation of structure 31 through 90 ° as a result of the action of the motor / reduction gear unit 32 are supplied to a stacker, generally indicated at 36 in Figure 5, in order to be stacked, as is usual in the art.

In the embodiment illustrated in Figures 6 to 9, the work station 5 is replaced by a double work station, or a bead station 40 comprising a plurality of annular flange members 26, controlled, for example through a unit operated with fluid 30 and, for example, a station 41 for piercing the bases of the objects 2. In this way, after collecting the objects, the extraction plate 4 makes a first stop with the objects 2 attached thereto in the workstation 40, wherein all the groups of objects are flanged, while still attached to the extraction plate 4 (Figure 6 and 7) and a second stop in the drill station 41, where a plurality of tools 42 ( one for each object 2 in the stamped group) pierces the bases of the objects as a result of the thrust of a linear actuator, such as a unit operated with fluid 43 (Figures 8 and 9). After drilling, the extraction plate 4, releases the objects 2 and returns to the extraction position to start another work cycle. The perforated objects 2 are, in turn, removed from the work station 41 in a suitable manner in order to be stacked or otherwise handled. Figure 10 illustrates an embodiment in which a press 3 is driven by two extraction plates 4a and 4b, which move alternately towards the extraction position and hold the objects 2 of a mold secured thereto, so that three successive handling or processing of the objects is carried out immediately after they are removed from the mold, while remaining secured through all three operations. At this point, the extraction plate 4a and 4b is carried on the end of a corresponding support arm 45, the other end of which is fixed on a fork member 46, whose longitudinal axis is perpendicular to the plane where the extraction plate lies. correspondent. The fork member 46 is controlled by a drive unit, for example of a motor / reduction gear unit 47, in order to perform angular movements to move the corresponding extraction plate between an extraction position and a first extraction station. work, for example, an edge or beading station 40. Each motor / reduction gear unit 47 with the corresponding member 46 is movably mounted so as to move on a guide 48 and cause movement therethrough. through a linear actuator comprising, for example, a chain section 49 driven by a motor / reduction gear unit 50.

With this arrangement, each extraction plate 4a, 4b is arranged to move towards the extraction position to pick up a group or mold objects 2 of the female die 6a, to transfer the objects towards a first work station 40 through the rotation of its respective arm 45, and then, moving along the respective guide 48, is subsequently moved towards a second work station, for example, a drill station 43, while the other station plate is moved to the position of extraction, and to a third workstation, for example, an external labeling or marking station 51. Figures 11 to 14 illustrate different embodiments of the extraction plate 4. Figure 11 shows an extraction plate 4 equipped with formers or shutters 34, each of which has a peripheral shoulder 52 against which the edge of a thermoformed object 2 can abut. Each former 34 has one or more axial holes 53a in communication with the main holes 53b, for example, provided in the body of the extraction plate 4, which can be placed in communication with a suction pump 56 operated by an electric motor 57, through a duct 54, which can be deactivated through, for example, an electrically operated valve 55.

When, during the extraction step, the plate 4 moves towards the objects 2, the formers 34 are placed in communication with the suction pump 56 to promote partial insertion of each object, seating it against the shoulder 52 of its respective former. Once the objects 2 have been transferred to each work station, the electric valve 55 is controlled, for example, through a programmed control unit, which is not shown in the drawings, which places the duct 54 in communication with the surrounding atmosphere and in this way gives an end to the retention action exerted by the negative pressure previously created within each object, as a result of which, the objects can be released and removed from the support plate 4. In the As illustrated in Figure 12, the shoulder 52 of each obturator or former 34 is provided with an annular groove 58, which acts as a seat for an elastic flange seal 59, which is designed to removably couple the internal surface of the seals. objects 2. In this case, it is not necessary to create a negative pressure inside the objects 2 in order to retain them on their respective obturators, and the pump 56 will be of the pressure type for send an air jet to the end of the object processing operation, in order to remove them from the extraction plate 4.

The embodiment illustrated in Figure 13 provides means to maintain the objects 2 on respective shutters 34, which comprise one or more suction cups 60 seated in the frontal depression 61 in each respective shutter or former 34, and which can move against the loading force of a spring 62. Each suction cup is in communication with a pump 56 in a manner completely similar to the embodiment in Figure 11. Below the object 2 held on the extraction plate 4, a plate 70 is shown. , which can be moved towards, and away from an object 2, which is designed to place a label, generically indicated at 71, on the outside of the base. Figure 14 illustrates a mode of means for retaining objects 2 on respective formers 34 comprising at least two cantilevered projections 63 of a respective control member 64, which is rotatably mounted on the extraction plate 40, and which can be controlled (for example, through a rack mechanism, which can be operated through a suitable linear actuator, as generally indicated at 66) in order to make partial angular movements in both directions, thus moving the projections corresponding either to the shoulder 52 of a former to a coupling position or away from the shoulder 52 in an uncoupled position. This arrangement is particularly advantageous for holding objects 2 on the extraction plate 4 from the outside. The drawing diagrammatically illustrates a unit 41 for piercing the base of the objects, wherein each former also supports a corresponding head 65 provided with axial holes corresponding to each hole, which has to be made in the bases of the objects which, is designed To lean against the bases of the objects to act as a push plate in order to avoid deformation of the bases of the objects and to act as a guide for the drill bits. It will be noted that the extraction and processing apparatus described above makes it possible to perform one or more procedures in a group of molded or thermoformed objects easily and reliably during one or more thermoforming cycles of a thermoforming machine immediately subsequent to the removal of the thermoforming machine. press The extraction and processing apparatus described above can be subjected to many modifications and variations within the scope of the protection defined by the claims. In this way, for example, the same apparatus can also serve as a press where the female die is mounted at the top and the male die is mounted at the bottom, where both dice move along a horizontal plane.

Claims (11)

1. An apparatus for extracting and processing thermoformed objects from a thermoforming machine, characterized in that it comprises one, or a sequence of units or stations for processing or processing thermoformed objects produced in the thermoforming machine, arranged in sequence immediately downstream of the thermoforming machine and at least one extraction plate, which is desigto move synchronously with the thermoforming machine between a position where it collects a group of thermoformed molded objects through the thermoforming machine, and at least one processing station. handling for the group of thermoformed objects thus removed and keeping them secured thereto during the respective procedures or operation.

2. The apparatus according to claim 1, characterized in that the extraction plate has a former or seat for each object that is to be removed and processed or handled on its side facing the objects.

3. The apparatus in accordance with the claim 2, characterized in that it comprises a support arm for each extraction plate, which at one end thereof, supports the respective support plate, a carriage or slide, which is connected to, or is integral with, the other end of the arm. support, in order to move the respective extraction plate, slide or roller guide means for the carriage or slide, and drive means for the carriage or slide that act synchronously with the cycle of operation of the thermoforming machine.

4. The apparatus in accordance with the claim 3, characterized in that the carriage or slide comprises a hinge fork for the support arm of its respective extraction plate and drive means for causing the support arm to perform angular movements.

5. The apparatus according to any of claims 2 to 4, characterized in that the extraction plate is arranged along the carriage or slide of at least one work station at opposite lateral processing thrusts applied to the objects.

6. The apparatus according to any of the preceding claims, characterized in that the, or a work station includes an edge or flanging unit arranged to flange the still hot objects attached to the extraction plate in cooperation with the corresponding formers or seats on the elimination plate.

7. The apparatus according to claim 6, characterized in that the flange unit has a plurality of reception and support seats for the base or bottom of each object, in a group or objects of molding, a support arm for each seat of reception, a connection and stiffening frame between the various support arms, an actuator desigto move the frame between a position close to the extraction plate and a distance away from it, an annular member, which can move coaxially and around each receiving seat and having a front end that is supported by an annular bead former or former, which is arranged to act together with a respective former on the extraction plate, a support plate to which the other end is fixed of each ring member or is integral with, and has a corresponding opening for each receiving seat to allow a corresponding receipt seat to pass through through it, and actuating means for the support plate.

8. The apparatus according to claim 7, characterized in that the flanging unit is mounted on a support and has actuating means for causing angular movement thereof around an axis.

9. The apparatus according to any of the preceding claims, characterized in that the, or a work station comprises a unit for piercing the bases of the objects.

10. The apparatus according to any of the preceding claims, characterized in that the, or a work station includes a unit for labeling or marking the objects.

11. The apparatus according to any of the preceding claims, characterized in that the, or a work station incorporates a unit for sterilizing the objects.