APPARATUS FOR TRANSFERRING ORDERLY SEQUENCES OF BOTTLES MADE OF THERMOPLASTIC MATERIAL

Abstract: Apparatus for processing plastic hollow bodies, comprising a blow-moulding station (1), means for introducing thereinto a sequence of trains of preforms, an ejection station (8) adapted to separate the ejected hollow bodies, and means provided downstream of said ejection station (8) to handle said hollow bodies, said means comprising a conveyor belt (3) capable of being driven by a pulley (6) and provided with means (plugs) (4) adapted to pick up said hollow bodies. The pulley (6) is provided on its outer surface with a plurality of ejectors (10) that are arranged to sequentially engage and disengage said pick-up means (4) so as to release the blow-moulded hollow bodies therefrom. Beneath said ejectors (10) there is arranged a guide (11, 12) which is adapted to intercept said so released hollow bodies, and which is provided with two parallel rails (11, 12) adapted to retain said hollow bodies by their neck (5) portion and push them, preferably by means of jets of blown air (16, 17), towards their utilization apparatuses.

Description: APPARATUS FOR TRANSFERRING ORDERLY SEQUENCES OF BOTTLES MADE OF THERMOPLASTIC MATERIAL DESCRIPTION The present invention refers to an improved apparatus for handling on a large-scale basis, and m an orderly sequential manner, containers made of thermoplastic material, m particular polyethylene terephtalate (PET) and polypropylene (PP), by submitting appropriate semi-rinished moulded parts generally .known as "paπsons" or "preforms" to a so-called blow-moulding process. In particular, the present invention can be used in a most advantageous manner when the described apparatus is associated to a preform production plant, le. an plant that is also .known as a single-stage one, but can of course be effectively used also m connection with plants that are fed with previously produced preforms to only carry out the final blow-moulding phase (two-stage plants). As a matter of fact, these processes for the production of the above cited lands of containers are generally known to be able to be schemancally divided into two basic topologies, le single-stage and two-stage processes. In two-stage processes, a previously moulded preform or parison in a substantially amo hous state is heated up again to its preferred molecular orientation temperature, at which it is then blow-moulded to the desired shape. As used this particular context, the term "two-stage process", or simply "two-stage", is intended to mean any process that produces a preform or parison which must subsequently be heated up again from room temperature to the respective blow-moulding temperature. On the contrary, single-stage processes are so defined owing to the fact that they are capable of moulding said so-called preform or parison, transferring the same preform or parison from the injection or ej trusion mould (after it has cooled down to some appropriate temperature) to a conditioning station where said preform or parison is allowed to evenly balance down to a preferred molecular orientation temperature. Said preform or parison is then transferred to a blow-moulding mould, where it is moulded to the desired shape. The state of the ait concerning the techniques implemented for solving the various problems in connection with the processes of injection-moulding or extrusion and blow-moulding of the preforms, as well as the synchronization of all these processes with each other in view of increasing the productivity of the whole production plant, is exhaustively described in the European patent application EP 0 768 165, filed by the same Applicant, which describes also the most significant patent literature existing on the matter and to which reference should therefore be made. Both above cited types of production methods involve the use of a (per se .known) blow-moulding station and the therewith associated handling means for transferring and releasing the preforms and/or the blow-moulded containers after the blow-moulding phase. Largely k . nown in the art are also the problems connected to the start-up of a single-stage plant. In particular, when such kind of plants are being started, the need arises teclmic-illy for the plant to be brought to steady-state conditions, which means the need for the blow-moulding moulds, but in particular also the injection moulds in the stage where the preforms are e.xtruded/injection-moulded, to be brought to a pre-determined temperature, until preforms with the desired properties can be obtained As a result, after the plant has been started, a certain quantity of preforms are unavoidably produced for a certain period of time, or number of cycles, which, owing to them not having yet the desired properties, cannot be used and must therefore be discarded. To this purpose, such a type of plant is therefore started initially so as only the section thereof devoted to the production of preforms is actually operated, wherein said prefoπns, after having been removed from the moulds, are handled and transferred in the usual manner, and are eventually moved across the blow-moulding station Since such preforms are not yet capable to be used for blow forming, owing to the above cited leasons, the blow-moulding station is not yet operating and, as a consequence, said preforms move, without being actually processed, between the two blow-formmg mould halves which remain in their open position When they move out of said mould halves, the preforms, winch are usually oigamzed in groups that move in a synchronized manner, otherwise known as "prefoim trains" in the art, aie transported, with generally per se known means, towards an ejection station where they are separated from the plant and usually discharged into appropriate bins or containers Anyway, they are eliminated from the production piocess .After a certain penod of initial operation, the plant then reaches steady-state conditions, so that it can from now on be operated m all of its sections As a consequence, also the blow-moulding station is now running, so that the preforms are blow foimed there and converted into finished containers which are again transported, m the same manner as illustrated above, to the ejection station that dischaiges them into appiopnate baskets, bins or similar containers adapted to collect the finished product, from which they are then brought to the utilization plants, ie. usually the .filling plants. Therefore, it clearly emerges that the need for two groups of products to be separated, ie. the preforms or the blow-formed containers that are produced during the two subsequent phases of operation under start-up and steady-state conditions of the plant, practically involves the need for a phase to be provided of selective separation from the plant and, therefore, also of selective separation of the containers that are blow-moulded after the steady-state conditions of the plant have been reached. It clearly ensues that such a need for a selective separation phase to be included and operating even after the plant has reached steady-state conditions, causes the orderly and substantially continuous flow of containers from the blow-moulding station to the utilization plants thereof to be practically interrupted. As a result, such a separation phase generates a considerable diseconomy since it practically prevents the production flow of blow-moulded containers from being automatically synchronized with the utilization flow of the same containers in the plants, such as filling plants, provided downstream. As far as two-stage plants are concerned, ie. practically the preform temperature conditioning station and the blow-moulding station, the situation is substantially similar to the one that has been just described with reference to single-stage plants, owing to a persisting need for a start-up phase to be provided in order to bring all of the various sections of the plant up to steady-state temperature. Also in connection with two-stage plants, therefore, the need still arises for an initial run of preforms to be produced, which must then be "discarded" and separated selectively from the plant, so that the same drawbacks and diseconomies as the afore mentioned ones are encountered also in these kind of plants. In consideration of what has been stated above, it is therefore a main purpose of the present invention to provide an apparatus and a method applying to the phases that follow the actual blow-moulding phase of a plant for the production of blow-moulded containers, so as to eliminate all of the afore cited drawbacks and enable such plant to feed in a substantially continuous and automatic manner the utilization plants arranged downstream, without any interposition of phases that are non-automatic or such as to anyway cause the continuity of flow of blow-moulded containers feeding such utilization plants to be interrupted. Furthermore, such an apparatus must be easily implemented through the use of readily available techniques and, therefore, be a reasonably low-cost one. Such main aim of the present invention, along with further features thereof, is reached in an apparatus that is made and operates as recited in the appended claims. The present invention may take the form of a preferred embodiment such as the one that is described in detail below by way of non-limiting example with reference to the accompanying drawings, in which: - Figure 1 is a vertical side view of an apparatus according to the present invention; - Figure 2 is a view along the section identified as E-E section of Figure 1 ; - Figures 3 and 4 are views along the sections identified as B-B section and C-C section of Figure 1 , respectively; - Figure 5 is a view along the section identified as A-A section of Figure 1 ; - Figure 6 is an enlarged view of a detail of Figure 4. The basic peculiarity of the present invention lies in the use of particular methods and means for releasing and separating the blow-moulded containers from a conveyor belt to which they are applied by means of appropriate devices that are generally .known in the art as "pick-up plugs". Said release means, along with the thereto associated means for routing the blow-moulded, .finished containers towards the utilization lines thereof, are arranged downstream of the traditional ejection stations wliich in tum are provided downstream of the blow-moulding stations. Referring now to Figure 1 , which is a schematical view of a traditional blow-moulding plant with associated finished-container ejection station, the same plant can be noticed to include a blow-moulding station 1 (which is shown here only symbolically), a conveyor belt 3 adapted to feed said blow-moulding stations with synchronized groups or trains of preforms and provided with a plurality of pick-up plugs 4 adapted to engage the necks 5 of respective preforms to transport them along the direction of movement of said conveyor belt 3, a wheel 6 acting as a driving pulley for said conveyor belt. Downstream of the blow-moulding station there is arranged a part ejection station, of a per se .known type and therefore only shown here as generally indicated at 8, which is provided with means adapted to separate in a synchronized m.anner the various successive trains of preforms or blow-moulded containers from the related pick-up plugs provided on said conveyor belt 3. Once such a separation has so taken place, said preforms or blow-moulded containers fall by gravity into appropriate bins or similar containers (not shown) that are then sent to appropriate utilization lines (or recovery/recycling lines in the case of rejects). As this has already been pointed out earlier in this description, both non-blown prefoπns produced during the plant start-up period before steady-state conditions are reached and, after said steady-state conditions are eventually reached, blow-moulded containers ready for further use, ie. usually for filling. The present invention essentially consists in providing said .kind of plant with means which, when arranged downstream of said ejection station 8, are capable of separating solely the blow-moulded containers from said conveyor belt, as well as transferring the same containers, in an orderly sequence and at a continuous, constant rate, onto a special transport line adapted to route said containers towards their final utilization, ie. filling apparatuses. It clearly emerges that, if said means are arranged downstream of said ejection station 8, the latter must be provided with selectively actuatable devices adapted not to eject, but rather to retain the blow-moulded containers in order to enable such containers to travel on until they reach the zone where they are orderly separated therefrom and sent in a continuous manner to said transport line for conveyance towards said utilization apparatuses. Said actuation means shall of course be such as to also enable non-blown preforms to be ejected during the plant start-up period before steady-state conditions are reached. With reference to the Figures, said means arranged downstream of the ejection station 8 can be noticed to include: - a wheel 6 acting as a driving pulley and provided with ejection elements 10 adapted to successively engage and disengageinside said pick-up plugs 4 so as to eject the blow-moulded hollow bodies that are applied thereto; - a guide comprising two rails 11 and 12 arranged at a distance D that is slightly smaller than the diameter C of the neck 13 of said hollow bodies, but larger that the diameter B of the blown portion 14 of said hollow body situated immediately beneath said respective neck portion, as illustrated in Figure 6; from the illustration in Figure 4 it can be noticed that said guide is arranged in a substantially horizontal position and is aligned with the vertical projection of said conveyor belt and said pulley. At the side of said rails, and parallelly with respect thereto, there are provided respective hollow conduits 16, 17 which are provided with a plurality of slits 18 and 19, respectively, facing the interior of the guide at the same height as the one at which the necks of said hollow bodies come to situate themselves; said slits are aligned according to and oriented in the direction of movement of the blow-moulded hollow bodies. Said hollow conduits are connected, via appropriate conduits 20, to air-flow generators (blowers) 21 adapted to generate such air flows at an appropriate rate and pressure. The operations of the above cited means is as follows: As best shown in Figures 1 , 2 and 3, the pick-up plugs 4 are caused to move forwards by said conveyor belt 3 until they reach a position in which said respective necks 13 engage with their upper portion said rails 11 and 12 (Figure 4) without actually touching them. As they move further on along their travel path, respective ejection elements 10 provided on the outer side of the pulley penetrate the interior of said pick-up plugs and push off the respective hollow bodies therefrom, as this is best shown in Figure 3. Since they are no longer supported by the respective pick-up plugs, said blow-moulded bodies tend to fall, but are immediately retained by their respective neck portion by said rails 11 and 12. The physical arrangement of the various above described elements is such that the position in which said pick-up plugs enter said rails comes before the position in which said ejection elements engage the necks of the respective hollow bodies, so that all said hollow bodies are separate in a sequence from the respective pick-up plugs and sent, again in a sequence, along said guide. .After the hollow bodies are so ejected by the respective ejection means and then so retained by said rails, the movement thereof along said rails may be ensured by any of a plurality of means, provided that these are adapted to automatically and sequentially transportsaid hollow bodies towards their utilization plants, wherein said means may be driven in any of various .known methods, eg. electrically, mechanically, pneumatically or the like. In a preferred manner, according to an improved embodiment of the present invention said means are based on an air jet that, owing to its being suitably oriented and coming from said plurality of subsequent slits 18 and 19 provided along the travel path of said hollow bodies, takes the foπn of an air jet blowing in a substantially continuous manner onto the various necks 5 of the hollow bodies and so pushes them in -an orderly manner along said rails up to the utilization plants. .Although the invention has been described here based on the example of preferred embodiments thereof and using a generally .known teπninology, it shall not be intended as being limited thereby, since it is well within the ability of anyone slalled in the art to develop a number of variants from the teachings thereof. The appended claims shall therefore be understood as covering all such possible obvious modifications that are within the ability of those skilled in the art and do not depart from the actual scope of the present invention.

Claims: CLAIMS 1. Apparatus for processing hollow bodies of plastic material, winch may be both blow-moulded containers and not yet blow-moulded prefo.rms, and transferring said hollow bodies into collecting means or towards utilization lines, comprising at least a blow-moulding station (1), means arranged downstream of said blow-moulding station and including: - an ejection station (8) adapted to separate said hollow bodies removed from or coming out of said blow-moulding station and corresponding to the trains of preforms that are fed in a sequence to said blow-moulding station, and - means that are arranged downstream of said ejection station for handling said hollow bodies, these means comprising a conveyor belt (3) adapted to be driven by a pulley (6) and provided with members or pick-up plugs (4) for picking up and releasing said hollow bodies, - a pulley (6) arranged vertically and adapted to drive said conveyor belt, characterized in that downstream of said ejection station there are provided separation and transfer means adapted to separate said hollow bodies from the respective pick-up plugs (4) in the form of blow-moulded containers and send them in a substantially continuous sequence towards their utilization apparatuses. 2. Apparatus according to claim 1 , characterized in that said separation means are adapted to separate the hollow bodies from the respective pick-up plugs (4) sequentially. 3. Apparatus according to claim 2, characterized in that: - said separation means comprise said pulley which is provided on its outer surface with a plurality of ejecting elements (10) arranged at a pre-established distance and adapted to orderly and sequentially engage the interior of said pick-up plugs (4) so as to separate said blow-moulded hollow bodies therefrom, - beneath said ejecting elements (10) there is arranged a guide that is adapted to intercept and retain said so separated blow-moulded hollow bodies, said guide comprising two parallel rails (11 , 12). 4. Apparatus according to claim 3, characterized in that said parallel rails are arranged at a distance (D) that is smaller than the diameter (C) of the neck (13) of the hollow bodies, but larger than the diameter (B) of the blown pomon (14) of the respective hollow body. 5. Apparatus according to claim 4, characterized in that said parallel rails are provided with handling means adapted to automatically and sequentially transport said hollow bodies towards their utilization apparatuses. 6. Apparatus according to claim 4 or 5, characterized in that said handling means comprise two hollow conduits (16, 17), which are aligned along said two respective rails (11 , 12) and in which there is provided a respective plurality of slits (18, 19) facing the interior of the respective rail and oriented in the direction of movement of the blow-moulded hollow bodies. 7. Apparatus according to claim 6, characterized in that said hollow conduits are connected to one or more blowing means (21) generating an air flow that is conveyed into said conduits. 8. Apparatus according to claim 7, characterized in that air-flow pressure, distance, width and orientation of the slits, as well as configuration of the rails are adapted to enable said blow-moulded hollow bodies to be pushed in an orderly sequence towards their utilization apparatuses. 9. Apparatus according to any of the preceding claims, characterized in that it is provided with means for actuating and controlling the operation of said blow-moulding station and said ejection station in such a manner as to selectively bring about following operational modes: - blow-moulding station non-operating, ejection station operating; - blow-moulding station operating, ejection station non-operating, under actuation of said air-flow generating means ( 1). 10. Method for producing and transferring hollow blow-moulded plastic bodies, including the phases in which said hollow bodies are blow-moulded, separated from a conveyor belt, and transferred to their utilization apparatuses, characterized in that said separation phase is carried out in a sequential manner by successively and orderly releasing at a pre-determined rate said hollow bodies from said conveyor belt and placing them in an orderly row along a transfer means. 11. Method according to claim 10, characterized in that said transfer means supports and guides said hollow bodies by means of a pair of rails that are adapted to retain said hollow bodies by their respective neck portion. 12. Method according to claim 11, characterized in that said hollow bodies, so arranged in said pair of supporting rails, are caused to move along by a plurality of air jets blown at an appropriate angle that is preferably symmetrical with respect to the direction of movement of said hollow bodies. 13. Method according to any of the claims 10 to 12, characterized in that said phases in which said hollow bodies are separated and then transferred are adapted to be excluded selectively. AMENDED CLAIMS [received by the International Bureau on 28 June 1999 (28.06.99); original claims 1-13 replaced by new claims 1-7 (3 pages)] 1. Apparatus for processing hollow bodies of plastic material, which may be both blow-moulded containers and not yet blow-moulded preforms, and transferring said hollow bodies into collecting mems or towards utilization lines, comprising at least a blow-moulding station (1), means arranged downstream of said blow-moulding station and including: - an ejection .station (8) adapted to separate said hollow bodies removed from or coming out of said blow-moulding .station and corresponding to the trains of preforms that are fed in a sequence to said blow-moulding station, and - means that are arr.anged downstream of said ejection station for handling said hollow bodies, these means comprising a conveyor belt (3) adapted to be driven by a pulley (6) and provided with members or pick-up plugs (4) for picking up and releasing said hollow bodies, - a pulley (6) arranged vertically and adapted to drive said conveyor belt, - separation and transfer means downstream of said ejection station adapted to separate said hollow bodies from the reispective pick-up plugs (4) in the form of blow-moulded contc-iners and send them in a substantially continuous sequence towards their utilization apparatuses, characterized in that: - said separation means comprise said pulley which is provided on its outer surface with a plurality of ejecting elements (10) arranged at a pre-established cListance and adapted to orderly and sequentially engage the interior of said pick-up plugs (4) so as to separate said blow-moulded hollow bodies therefrom, - beneath said ejecting elements (10) there is arranged a guide that is adapted to intercept and retain said so separated blow-moulded hollow bodies, said guide comprising two p-arallel rails (11, 12). 2. Apparatus according to claim 1 , characterized in that said handling means comprise two hollow conduits (16, 17), which are aligned along said two respective rails (11 , 12) and in which there is provided a respective plurality of slits (18, 19) facing the interior of the respective rail and oriented in the direction of movement of the blow-moulded hollow bodies. 3 Apparatus according to claim 2, characterized in that said hollow conduits are connected to one or more blowing means ( 1) generating an air flow that is conveyed into said conduits. 4. Apparatus according to claim 3, characterized in that air-flow pressure, distance, width and orientation of the slits, as well as configuration of the rails are adapted to enable said blow-moulded hollow bodies to be pushed in an orderly sequence towards their utilization apparatuses. 5. Apparatus according to any of the preceding claims, characterized in that it is provided with means for actuating and controlling the operation of said blow-moulding station and said ejection station in such a manner as to selectively bring about following operational modes: - blow-moulding station non-operating, ejection station operating; - blow-moulding station operating, ejection station non-operating, under actuation of said air-flow generating means (21) . 6. Method for producing and transferring hollow blow-moulded plastic bodies, including the phases in wliich said hollow bodies are blow-moulded, separated from a conveyor belt, and transferred to their utilization apparatuses, said separation phase being carried out in a sequential manner by successively and orderly releasing at a pre-determined rate said hollow bodies from said conveyor belt and placing them in an orderly row along a transfer means, characterized in that said transfer means supports and guides said hollow bodies by means of a pair of rails that are adapted to retain said hollow bodies by their respective neck portion. 7. Method according to claim 6, characterized in that said hollow bodies, so arranged in said pair of supporting rails, are caused to move along by a plurality of air jets blown at an appropriate angle that is preferably symmetrical with respect to the direction of movement of said hollow bodies.

Inventors: DE MARCHI ELIGIO, DE MARCHI, ELIGIO
Applicants: MARCHI ELIGIO DE, SIPA SPA, DE MARCHI, ELIGIO, SIPA S.P.A.
Application year: 1998
Main classification: B65G51
IPC codes: B29C49, B65G17, B65G47, B65G51