FR3035650A1 - "TREATMENT STATION EQUIPPED WITH HOLLOW BODY CONVEYOR HAVING A BIFURCATION CONNECTION" - Google Patents

Abstract

The invention relates to a station (14) for treating hollow bodies (12) for an installation (10) for manufacturing containers made of thermoplastic material, comprising a conveyor (20) for conveying the hollow bodies, comprising a circuit formed by at least one a guide rail (22) along which shuttles (24) are able to circulate by boarding at least one hollow body (12), each shuttle (24) being controlled individually, characterized in that the circuit comprises at least one branch Secondary branch (26) via at least one upstream bifurcation branch (54).

Description

TECHNICAL FIELD OF THE INVENTION The invention relates to a hollow-body treatment station for an installation for manufacturing containers made of thermoplastic material, comprising a conveyor for transporting the hollow bodies, the conveyor comprising a circuit formed by at least one guide rail along which shuttles are able to circulate by boarding at least one hollow body, each shuttle being individually controlled in displacement, the circuit comprising at least one first main path having at least one treatment section along which the transported hollow bodies undergo a treatment, a hollow body loading section upstream of the treatment section and an unloading section downstream of the treatment section.

TECHNICAL BACKGROUND OF THE INVENTION The manufacture of thermoplastic containers, such as bottles, flasks, etc. is generally made from preforms, sometimes called blanks, which are introduced into a molding device with which are associated forming means, for example blowing or stretch-blow molding. In the remainder of the description and in the claims, the preforms and the finished containers will be referred to generically as "hollow bodies". Traditionally in this technical field, the preform and the finished container have an identical neck or neck. As a result, the same support member 3035650 2 of a preform by its neck is also adapted to support a finished container. Before being shaped into a final container, the preforms undergo several treatments along a running path. The preforms can thus undergo a heating treatment, a decontamination treatment and a forming. In the following description. The container manufacturing facility is fed with preforms that are not able to be directly formed. Prior to blow molding or stretch-blow molding, the preforms are heated in a heating station so as to give them a sufficiently malleable structure for the blowing operation. Such large-scale manufacturing facilities for 15 containers are equipped with a heating station comprising a heating tunnel provided with means for heating the preforms. This heating tunnel determines a heating path along which the preforms are generally conveyed by a high speed conveyor without stopping. The tunnel has a length sufficient to allow the heating of the preforms during their crossing. The conveyor comprises individual preform support members which run along a loop path, a section of which conveys the preforms along the heating path 25 which passes through the heating tunnel. The support members are generally formed by mandrels which are capable of driving the preform transported in rotation about its axis to ensure a homogeneous heating of the preform. Furthermore, the preforms to be heated are fed one after the other by an input device to an input area in the heating station. On this input device, two successive preforms are spaced apart by a first predetermined spacing.

Likewise, at the outlet of the heating station, the hot preforms are transferred to an outlet device on which two successive preforms are spaced apart by a determined second spacing. The second gap is generally equal to the first gap. When the preforms run in the heating tunnel with too large a gap between two preforms, a portion of the heating radiation is spent in a loss by passing between the preforms.

According to another disadvantage of the known conveyors, when a shuttle has a malfunction, or when a shuttle requires a preventive maintenance action or a cleaning, it is necessary to interrupt the operation of the conveyor so that an operator can realize A maintenance operation, such as repair or replacement of the shuttle. Such an interruption causes a standby of the entire manufacturing facility, and therefore a temporary stop of the production of containers. This can have negative financial consequences for the container manufacturer. BRIEF SUMMARY OF THE INVENTION The invention proposes a heating station of the type described above, characterized in that the circuit comprises at least one secondary branch connected in shunt with the main path via at least one upstream branch. bifurcation. According to other characteristics of the heating station: the at least one secondary branch is connected to the main path downstream of the upstream bifurcation branch, via a junction downstream branch; - the treatment station is formed by a preform heating station which comprises a heating tunnel, the treatment section carrying the preforms through the heating tunnel so that the preforms loaded on the shuttles are heated; the at least one secondary branch forms a siding; the secondary branch makes it possible to store a plurality of shuttles; The main path forms a closed loop, the unloading section being connected to the loading section to ensure the return of the empty shuttle to the loading section; - The bifurcation branch is arranged downstream of the processing section and the junction branch is arranged upstream of the loading section; the at least one secondary branch forms a secondary treatment section which extends parallel to the main path treatment section inside the heating tunnel; The bifurcation branch is arranged downstream of the loading section and upstream of the main path processing section, while the junction branch is arranged downstream of the main path processing section and upstream of the main section unloading.

The invention also relates to a method for controlling the shuttles of the heating station produced according to the teachings of the invention, characterized in that it comprises: a distribution step during which the shuttles are switched one by one alternatively to the treatment section of the main path or to the secondary branch so that the shuttles run on two lines in the heating tunnel; - a circulation step on the treatment section during which the shuttles circulating in the heating tunnel on the main road treatment section are spaced apart by a determined step in the direction of movement, the 5 shuttles running on the secondary branch flowing with the same determined step and at the same speed as the shuttles of the main path processing section, with a shift of half a step compared to the shuttles of said section of treatment. According to a characteristic of the method, the determined pitch between the shuttles running on the same line is less than twice the length of a shuttle. BRIEF DESCRIPTION OF THE FIGURES Other characteristics and advantages of the invention will appear during the reading of the following detailed description for the understanding of which reference will be made to the appended drawings in which: FIG. above which schematically represents a container manufacturing installation comprising a heating station made according to a first variant of a first embodiment of the invention; FIG. 2 is a view similar to that of FIG. 1 which schematically shows a container manufacturing installation comprising a heating station made according to a second variant of the first embodiment of the invention; - Figure 3 is a top view which schematically shows a portion of a heating station made according to a second embodiment of the invention.

DETAILED DESCRIPTION OF THE FIGURES In the rest of the description, elements having identical structure or similar functions will be designated by the same references. In the remainder of the description, a longitudinal direction, directed from back to front according to the direction of movement of the preforms, will be adopted in a nonlimiting manner, a vertical direction, directed from bottom to top orthogonal to the plane of displacement of the preforms, and a transverse direction which is perpendicular to the two preceding directions. In the remainder of the description, the terms "upstream" and "downstream" will be used with reference to the direction of movement of the preforms 12 in an installation 10.

FIG. 1 shows a part of the installation 10 for producing large quantities of thermoplastic containers such as polyethylene terephthalate or PET. The manufacturing installation 10 is here intended to form containers from preforms 12 to be heated.

The manufacturing facility 10 has several processing stations. FIGS include in particular a station 14 for heating the preforms 12 and a station 16 for forming, here by blow-molding or stretch-blow molding, preforms 12 previously heated by said heating station 14. It will be appreciated that the plant may also include preform decontamination stations, or other processing stations well known to those skilled in the art for this type of application. The heating station 14 comprises a heating tunnel 18, which is here produced in three successive portions 18A, 18B, 18C. The heating tunnel 18 has been shown diagrammatically in FIG. 1. The two end portions 18A, 18C are arranged parallel to each other, while the second central portion 18B is arranged perpendicular to both of them. other portions 18A, 18C, in an end turn. The heating tunnel 18 defines a heating path, here in the form of a "U", which is intended to be traversed by each preform 12. Conventionally, such a heating tunnel 18 is delimited by two lateral walls (not shown) which form a tunnel. At least one of the walls is provided with heating means (not shown) emitting radiations heating the preforms, such as infrared lamps. The heating tunnel 18 may also be equipped with ventilation means making it possible to promote homogeneous heating of the preforms and making it possible to prevent overheating of certain components of the heating station 14. The heating station 14 also comprises a conveyor 20 which is intended to transport each preform 12 through the heating tunnel 18. In normal operation of the manufacturing installation 10, the conveyor 20 is here intended to transport the preforms 12 in a continuous manner, that is to say without interruption of the displacement 20 of the preforms 12. The length of the heating tunnel 18 and the power of the heating means are adapted so that the preforms 12 are heated to a temperature sufficient for their forming by the station 16 forming. The conveyor 20 comprises a circuit formed by at least one guide rail 22. Shuttle buses 24 are able to circulate along the guide rail 22. Each shuttle 24 is controlled in displacement individually, that is to say independently of the other shuttles 24. The circuit here extends in the same horizontal plane.

In the embodiment shown in the figures, the circuit forms a closed loop which serves only the heating station 14.

In a variant not shown of the invention, the circuit serves several processing stations, the heating station being traversed by an open section of the circuit. Such an architecture is called "sequential" because the same shuttle 5 is likely to serve sequentially several processing stations before returning to its starting point. The shuttles 24 and the circuit formed by the guide rails 22 are part of a linear synchronous motor. In such a motor, each guide rail 22 comprises a stator formed of a series of coils (not shown) which are distributed along the guide rail 22. Each winding is individually controlled to locally induce a magnetic field independently of the other windings. The coils are, for example, controlled by an electronic control unit (not shown) which is appropriately programmed. Each shuttle 24 is equipped with at least one permanent magnet which reacts with the magnetic field induced by each winding of the guide rail 22 to cause the displacement of the shuttle 24. In addition, each shuttle 24 is guided in displacement along the rail 22 guide. The pitch between two windings is sufficiently small to allow the windings of the guide rail 22 to be controlled so as to cause the displacement of each shuttle 24 independently of the other shuttles 24. Such a linear motor is for example sold by Beckhoff under the name "XTS". For further details concerning this technology, reference may be made to US-A1-2013 / 0.119.897, US-A1-2013 / 0.035.784, WO-A1-2013 / 143.783 or WO-A1-2013. /143.950. In general, this technology implemented in the context of the invention makes it possible to move all shuttles 24 in a queue in the same direction of movement along the circuit, here a counterclockwise direction. The speed of movement of each shuttle 18 can be controlled individually by an electronic control unit (not shown).

Each shuttle 24 comprises at least one member (not shown) for individually supporting a preform 12. Each shuttle 24 here comprises a single individual support member for a preform 12. This is for example a mandrel which is inserted vertically into a neck of the preform 12. Thus, each 10 shuttle 24 is able to transport a preform 12. The mandrel is for example mounted vertically sliding on the shuttle 24 between a low position preform preform and a high position ejection of the preform. The sliding is for example controlled by an electric motor 15 or by a cam system. In the embodiment shown in FIG. 1, the guide rail circuit 22 comprises a first main path 26 in a loop. The preforms 12 are transported in a queue along this main path 26. There are several sections in this main path in loop. Thus, the main path 26 has at least one section called "processing section 26B" which allows the shuttles 24 to transport the preforms 12 along a treatment path along which said preforms 12 undergo a treatment such as heating. , decontamination or forming. In the case of a heating station 14, the treatment path is formed by a heating path. The treatment section 26B extends from an inlet 28 of the heating tunnel 18 to an outlet 30 of the heating tunnel 18. The preforms are thus heated during their run on the treatment section 26B. A section called "section 26A loading" of the main path 26 is arranged upstream of the inlet 28 of the heating tunnel 18, according to the direction of circulation of the shuttles 24. The preforms 12 to be heated are loaded on the shuttles 24 traveling on this section 26A loading. Thus, the shuttles 24 arrive on this section 26A loading "empty" and they come out loaded with a preform 12 to heat.

A section called "unloading section 26C" of the main path 26 is interposed between the outlet 30 of the heating tunnel 18 and the loading section 26A, according to the direction of circulation of the shuttles 24. The hot preforms 12 are unloaded from the shuttles 24 traveling on this unloading section 26C. Thus, the shuttles 24 arrive on this unloading section 26C loaded with a hot preform 12 after passing through the heating tunnel 18 and they come out "empty". The manufacturing installation 10 also comprises a device 32 for entering the preforms 12 to be heated, causing the preforms 12 to heat in a queue to the section 26A for loading the main path 26 for loading onto the shuttles 24. 32 input is able to lead to the loading section 26A each preform 12 successively, two successive preforms 12 12 spaced apart from a first determined spacing input according to their direction of travel. In the example shown in Figure 1, the input device 32 is formed by a wheel 34 with notches 36. The wheel 34 is rotatably mounted about a vertical axis. The wheel 34 has at its periphery notches 36, each of which is capable of carrying a preform 12. Two neighboring notches 36 are circumferentially spaced apart from said first determined entry gap. In the embodiment shown in FIG. 1, the installation 10 also comprises a device 38 for outputting the hot preforms 12 which is capable of transporting the preforms 12 from the unloading section 26C of the guide rail 22 to the forming station 16. The output device 38 is 3035650 11 designed to embed the preforms 12 one after the other, two successive preforms 12 spaced apart by a determined second output gap according to their direction of movement.

In the example shown in FIG. 1, the output device 38 is formed by a wheel 40 equipped at its periphery with a plurality of arms 42. Each arm 42 has at its free end a support member such as a clamp 44 able to grasp a preform 12 by its neck.

The forming station 16 is here formed by a carousel 46 (only part of which is shown) which carries a plurality of molding units 48 at its periphery. The carousel 46 is rotatably mounted to move the preforms 12 during forming. Such a forming station is well known and will therefore not be described in more detail later. Generally, the circumferential gap between two neighboring molding units 48 is greater than the determined exit distance of the hot preforms 12. In this respect, the arms 42 are generally pivotally mounted and / or slidable on the wheel 40 to allow the gap between two successive preforms 12 to be changed during their transport to the forming station 16. Thus, the preforms 12 are spaced apart by a spacing adapted to the spacing between two molding units 48 during their transfer to the forming station 16.

As shown in the figures, the rail circuit 22 includes at least one secondary branch 50 connected in branch with a determined main branch 52 of the main path 26. This secondary branch 50 extends from an upstream end which is connected with the main path 26 via a first upstream branch branch 54 to a downstream end which is connected to the main path 26 by the intermediate of a junction 56 downstream junction with the main path 26.

As a variant not shown of the invention, the secondary branch 50 is a dead end which is connected to the main path 26 by only one of its ends via a one-way or two-way branch.

Of course, the secondary branch 50 is itself formed of at least one guide rail 22 for guiding and moving the shuttles 24. The branching branch 54 is designed to selectively switch a shuttle 24 to the main branch 52 or to the secondary 50 branch. Without limitation, examples of such a branch are described in WO-A1-2014 / 047104. The junction branch 56 is designed to allow a shuttle 24 traveling on the secondary branch 50 to engage the main path 26. According to a first embodiment of the invention which is represented in FIGS. 1 and 2, the secondary branch 50 forms a siding which makes it possible to exit at least one shuttle 24 from the main path without stopping the other shuttles 24.

This is particularly useful when a shuttle 24 is defective. The defective shuttle 24 is then selectively directed to the secondary branch 50 as it passes through the bifurcation branch 54, while all other functional shuttles 24 are oriented toward the main branch 52 to continue their course along the main road 26. Thus, it is not necessary to interrupt the production of containers to perform a specific maintenance operation on a particular shuttle 24. According to a very advantageous embodiment of the invention, the secondary branch 50 siding is long enough to store several shuttles 24. Thus, it is possible to replace a defective shuttle 24 running on the main path 26 by a shuttle 3035650 13 24 of functional replacement which is stored on the secondary branch 50. To do this, the defective shuttle 24 is routed to the secondary branch 50 as previously described via the bifurcation branch 54. The replacement shuttle 24 is moved on the secondary branch 50 so as to replace the defective shuttle 24 on the main path 26 through the junction 56.

The location left free by the defective shuttle 24 in the shuttle line 24 traveling on the main branch 52 moves in unison with the other shuttle 24 in the queue. The displacement of the replacement shuttle 24 is synchronized with the movement of the shuttles 24 traveling on the main branch 52 so that this replacement shuttle 24 engages the main path 26 when the space left free by the shuttle 24 defective passes at junction 56 junction. Such a secondary siding branch 50 is also capable of being used to modulate the amount of shuttles 24 traveling on the main path 26. This is particularly useful when the preform heating method and / or the preform dimensions are likely to change between two sets of containers.

In a first variant of the first embodiment shown in FIG. 1, the main branch 52 is formed by a portion of the heating section 26B which passes into the second turning portion 18B of the heating tunnel 18. The secondary branch 50 siding is arranged behind the turn, outside the loop formed by the main path 26. More particularly, this secondary branch 50 extends outside the heating tunnel 18. Thus, the bifurcation branch 54 is interposed between the first portion 18A and the second portion 18B of the heating tunnel 18, while the junction branch 56 is interposed between the second portion 18B and the third tunnel portion 18C This arrangement is particularly compact since it makes it possible to arrange this siding in the extension of the heating station portion 14 comprising the heating tunnel 18. This arrangement is quite satisfactory for modulating the amount of shuttles 24 traveling on the main path 26.

Nevertheless, for occasional use of the shuttles, this arrangement implies that the defective shuttles 24 are directed towards the secondary branch 50 after having embarked a preform 12. Moreover, in case of replacement, the replacement shuttle 24 is introduced without 15 preform in the shuttle line boarding a preform. This arrangement is also particularly suitable for purposefully ejecting defective preforms. Indeed, when a defective preform or poorly grasped by the mandrel is detected, it is easy to switch the shuttles which door to the secondary branch 50 to proceed to the ejection of this preform. This avoids having to eject valid preforms at the same time as the defective preform as is the case for ejection devices of the state of the art. FIG. 2 shows a second variant embodiment of this first embodiment in which the main branch 52 is interposed between the unloading section 26C and the loading section 26A of the main path 26. In this case, the bifurcation branch 54 is arranged downstream of the unloading section 26c and the junction branch 56 is arranged upstream of the loading section 26A. The main branch 52 and positioned in the main path 26 is traversed exclusively by shuttles 24 circulating "empty", that is to say, not embarking any preform. This configuration thus makes it possible to route shuttles 24 traveling in a vacuum to the secondary branch 50. If a faulty shuttle 24 is replaced by a replacement shuttle 24, there is no disturbance in the flow of the preforms 12. Furthermore, the shuttles 24 traveling on the heating section 26B are fully used. A second embodiment of the invention will now be described with reference to FIG. 3. The conveyor 20 described above advantageously allows to modulate at will the "P" pitch of circulation between two successive shuttles 24 by varying the speed of travel. circulation of each shuttle 24. The "circulation pitch P" is defined as being the longitudinal distance along the direction of movement between the same point 15 of two successive shuttles 24. Thus, two shuttles 24 in longitudinal contact with each other have a pitch "P" of circulation equal to the length of a shuttle 24. Thus, the pitch "P" minimum circulation is equal to the length of a shuttle 24. Such a modularity is very interesting to allow 20 to adapt the pitch "P" of circulation of the shuttles 24 flowing on the loading section 26A, respectively on the unloading section 26C, to the spacing of the preforms 12 onboard on the input device 32, respectively on the output device 38.

In the remainder of the description, the linear density of preforms circulating in the heating tunnel 18 is defined as being the ratio between the quantity of preform circulating in the heating tunnel and the length of the heating tunnel.

It is very advantageous to reduce the "P" passage of circulation of the shuttles 24 flowing in the heating tunnel 18. Indeed, this has the consequence that the spacing between the embedded preforms also decreases. In other words, the linear density of preforms 12 flowing in the heating tunnel increases. As a result, the radiation "R" heating emitted transversely by the heating means is better exploited.

However, the maximum diameter of a preform 12 is generally less than the length of a shuttle 24, the length being measured in the direction of movement of the shuttle 24. Therefore, even when the pitch "P" of circulation shuttles 24 is minimal, there remains a substantial spacing between two successive preforms 12 circulating on the heating section 26B. This second embodiment proposes an arrangement which makes it possible to increase the linear density of preforms 12 circulating in the heating tunnel 18 by moving the preforms 12 over two longitudinally offset rows so that the preforms 12 of each file are totally exposed to radiation "R" heating emitted transversely by the heating means. As shown in FIG. 3, a secondary branch 50 forming a secondary treatment section extends parallel to the section 26B for processing the main path 26 inside the heating tunnel 18. The branch 50 extends at the same height as the processing section 26B. The term "parallel" is used geometrically and not "derivation". In the example shown, the secondary branch 50 forming secondary treatment section extends over the entire heating path. The main branch 52 is thus formed by the entire section 26B of treatment of the main path 26. More specifically, the bifurcation branch 54 is arranged downstream of the loading section 26A and upstream of the main path 26B treatment section 26, while the junction branch 56 is arranged downstream of the processing section 26B. of the main path 26 and upstream of the unloading section 26C. During the operation of the heating station 14 carried out according to this second embodiment, the shuttles 24 5 traveling at the bifurcation branch 54 are pointed, during a distribution step, one by one alternately to the section 26B treatment of the main path 26 or to the secondary treatment section formed by the secondary branch 50.

The shuttles 24 are controlled to circulate on the section 26B treatment with a pitch "P" of traffic determined in the direction of travel. Similarly, the shuttles 24 traveling on the secondary branch 50 are spaced apart from said determined pitch "P".

The shuttles 24 traveling on the section 26B processing the main path 26 travel at the same speed as the shuttles 24 flowing on the secondary branch 50 treatment. However, the shuttles 24 travel on the secondary branch 50 with a shift of a half-step "1 / 2P" relative to the section 26 26B treatment of the main path 26. Thus, as shown in FIG. 3, each preform 12 carried by a shuttle 24 traveling on the secondary branch 50 is interposed longitudinally, depending on the direction of movement of the shuttles 24, between two preforms 12 carried by two consecutive shuttle buses 24 of the 26B path 26 main processing section. This allows each preform to receive the same amount of heating radiation "R" emitted transversely to the direction of movement of the shuttles 24. According to a particular case of the method, the pitch "P" determined between the shuttles 24 traveling on the same section of treatment is less than twice the length of a shuttle 24 taken in the direction of travel. More particularly, the shuttles 24 of the same section 26B, 50 of treatment are spaced a pitch "P" 3035650 18 determined so that the spacing between two successive preforms 12 is only slightly greater than the diameter of the body of a preform . This method thus makes it possible to use the "R" radiation emitted by the heating means optimally.

The two embodiments of the invention may of course be combined to simultaneously achieve the particular advantages of each of these modes. The presence of a secondary branch 50 towards which shuttles 24 can be selectively wired and from which shuttles can be selectively introduced on the main path 26 very advantageously makes it possible to improve the overall efficiency of the manufacturing facility 10. container. The invention has been described in application to a heating station 14. It will be understood that it is also applicable to other preform processing stations of the manufacturing facility. According to a variant of the invention shown in Figure 4, the main path 26 is likely to serve several processing stations 14, 16, 58 as part of a "sequential" architecture of the installation. In this case, the secondary branch 50A can be arranged at the output of a first processing station, here the heating station 14, to divide the stream of preforms 12 into two secondary streams. The preforms 12 are directed on each stream through a first branching branch 54A. A first portion of the preform stream 12 along the main path 26 thus feeds a second processing station, here a first forming station 16A, and a second part of the preform stream following the secondary branch 50A feeds a third processing station 16B. here, a second forming station 16B identical to said first forming station 16A.

Such an architecture makes it possible to increase the flow of preforms when the processing time of the second and third processing stations 16A, 16B is greater than the processing time of the first heating station 14.

This "sequential" architecture may extend according to the same principle to subsequent stations, for example filling stations, capping stations or labeling stations. Thus, at the exit of the first forming station 16A, the main path 26 is subdivided again into two distinct streams via a second secondary branch 50B. The second secondary branch 50B and the main path 26 each supply a processing station 58A, 58B, for example a labeling station. Containers 12 now 15 formed are directed on each stream through a second bifurcation branch 54B. Likewise, at the exit of the second forming station 16B, the first secondary branch 50A is subdivided again into two distinct streams via a tertiary branch 50C. The first secondary branch 50A and the tertiary branch 50C each supply a processing station 58C, 58D, for example a labeling station. Containers 12 now formed are directed on each stream through a third bifurcation branch 54C.

Such an architecture may be branched as many times as necessary to feed subsequent stations. It is also possible to join multiple branches to merge multiple streams through junction branches. 30

Claims (11)

REVENDICATIONS1. A hollow body treatment station (14) for a thermoplastic material container plant (10) comprising a conveyor (20) for conveying the hollow bodies, the conveyor comprising a circuit formed by at least one rail (22) along which shuttles (24) are able to circulate by boarding at least one hollow body (12), each shuttle (24) being individually controlled in displacement, to the circuit comprising at least a first path (26). ) having at least one treatment section (26B) along which the transported hollow bodies (12) undergo a treatment, a hollow body loading section (26A) upstream of the treatment section (26B) and a unloading section (26C) downstream of the treatment section (26B), characterized in that the circuit comprises at least one secondary branch (50) connected in shunt with the main path (26) via at least one a branch (54) upstream bifurcation. 20 2. Station (14) according to the preceding claim, characterized in that the at least one branch (50) secondary is connected to the main path (26) downstream of the branch (54) upstream bifurcation, through a junction (56) downstream junction. 25 3. Station (14) according to any one of the preceding claims, characterized in that it is formed by a station (14) for heating the preforms (12) which comprises a tunnel (18) for heating, the section (26B ) carrying the preforms through the heating tunnel (18) so that the preforms (12) loaded on the shuttles (24) are heated. 3035650 21 4. Station (14) according to any one of the preceding claims, characterized in that the at least one branch (50) secondary forms a siding. 5. Station (14) according to the preceding claim, 5 characterized in that the branch (50) secondary can store a plurality of shuttles (24). 6. Station (14) according to any one of the preceding claims, characterized in that the main path (26) forms a closed loop, the unloading section (26C) being connected to the loading section (26A) to ensure the return of the shuttles (24) empty to the section (26A) loading. 7. Station (14) according to the preceding claim, characterized in that the junction (54) bifurcation is arranged downstream of the section (26B) treatment and junction (56) junction is arranged upstream of the section (26A) loading. 8. Station (14) according to claim 3 taken alone or in combination with any one of claims 4 to 6, characterized in that the at least one branch (50) secondary 20 forms a secondary section of treatment which s' extends parallel to the section (26B) for processing the main path (26) inside the heating tunnel (18). 9. Station (14) according to the preceding claim, characterized in that the bifurcation branch (54) is arranged downstream of the loading section (26A) and upstream of the path processing section (26B) (26). main, while the junction (56) junction is arranged downstream of the section (26B) treatment of the main path (26) and upstream of the section (26C) unloading. 30 10. A method of controlling the shuttles (24) of the station (14) made according to any one of claims 8 or 9, characterized in that it comprises: 3035650 22 - a dispensing step during which the shuttles ( 24) are switched one by one alternately to the section (26B) of treatment of the main path (26) or to the secondary branch (50) so that the shuttles (24) run on two lines in the tunnel (18) of heating; - A circulation step on the section (26B) treatment during which the shuttles (24) flowing in the tunnel (18) for heating on the section (26B) treatment of the main path (26) are spaced apart from one another. not (P) determined according to the direction of movement, the shuttles (24) traveling on the secondary branch (50) flowing with the same pitch (P) determined and at the same speed as the shuttles (24) of the section (26B) of treatment of the main path (26), with a shift of half a step compared to the shuttles (24) of said section (26B) of treatment. 11. Method according to the preceding claim, characterized in that the determined pitch between the shuttles (24) traveling on the same file is less than twice the length of a shuttle (24),