DE102019108698A1 - Valve blow molding machine with rotatable valve body and process - Google Patents

Abstract

Reshaping device (1) for reshaping plastic preforms (10) into plastic containers (20) with a blow mold which forms a cavity within which the plastic preforms (10) can be expanded by being exposed to a flowable medium, with an impacting device (6) which is attached to a mouth of the plastic preforms (10) can be placed in order to apply the flowable medium to them and with a valve device (4) which controls the application of the plastic preforms (10) with the flowable medium, characterized in that the valve device (4) has a has a first tubular body (42) through which the flowable medium can be guided in a predetermined flow direction (S), and a carrier (50) which is movable with respect to this tubular body, a direction of movement in which the carrier (50) is opposite the tubular body is movable with the predetermined flow direction encloses an angle different from 0 ° and wherein the carrier has at least one first opening (52) and wherein the carrier (50) can be positioned in at least two positions relative to the tubular body (42), in one position the tubular body (42) is closed by the carrier and in the other position the flowable medium can be guided through the first opening (52).

Description

The present invention relates to a device and a method for reshaping plastic preforms into plastic containers. It has long been known from the prior art to heat plastic preforms and to expand them to form plastic containers by exposure to a flowable medium, in particular compressed air. More recently it has also become known to expand and fill the plastic preforms directly with a liquid and in particular with a product to be filled. The present invention relates to both of the above-mentioned procedures or to both the expansion of the containers with compressed air and with a liquid.

When expanding with liquid, it is common for the plastic preforms to be subjected to different pressures, for example a pre-blowing pressure of about 10 bar, an intermediate blowing pressure which can be, for example, 20 bar and also a final blowing pressure of, for example, up to 40 bar. Furthermore, it is also known that the already blown plastic containers are relieved again or an overpressure escapes from them.

In order to accomplish this supply with the different pressures, valve blocks are usually provided which have a multiplicity of valves which control the supply of pressure at different pressure levels. Several reservoirs can also be provided which are suitable and intended to hold the blown air at different pressures.

In such blow molding machines, the blown air is thus switched with an in particular pneumatically switching piston valve (seat valve).

It is known in the prior art that a small piston area seals the valve set and a large piston area is acted upon by the control air. The control air is switched with an electrically switching pilot valve. The volume flow of the pre-blow air must be adapted to the application. This can be achieved with a throttle, which in turn can be exchanged (throttles of different diameters can be used).

There are also solutions for proportional valves to regulate the volume flow during the blowing process. The blow piston with the blow nozzle is arranged in the center of a valve block. The blow piston is raised with a stretching rod, which also acts as a driver. As soon as a plastic preform has been entered, the blow piston lowers and the blow nozzle seals the mouth of the plastic preform.

The downward movement is preferably guided by the stretching rod. The force can be applied by a spring and optionally or additionally by a pneumatic spring (low pressure).

The blow piston also has an annular piston surface to which blow air is applied. This resulting force prevents the blowing piston from lifting off under the blowing nozzle during the blowing process.

As a rule, more than three, preferably four to seven, blowing valves are provided in the prior art and also within the scope of the invention (pre-blowing, intermediate blowing, for air recycling, finished blowing).

The pneumatically holding piston valves have a hysteresis behavior and a limited switching time repeat accuracy. With increasing machine performance, the requirement for precise switching times increases. The annular piston surface on the blow piston creates a dead space. The poppet valve design causes deflections and cross-sectional constrictions that are unfavorable to the flow, which restrict the flow. An optionally used pre-blow proportional valve is technically very complex and also cost-intensive.

The valve blocks used in the prior art are thus in some cases relatively complex to operate and, in principle, have a large number of valves.

The present invention is therefore based on the object of simplifying the operation of such a forming machine and in particular the design of the valve block. According to the invention, this is achieved by the subjects of the independent patent claims. Advantageous embodiments and developments are the subject of the dependent claims.

A reshaping device according to the invention for reshaping plastic preforms into plastic containers has a blow mold which forms a cavity within which the plastic preforms can be expanded by being exposed to a flowable medium, and an exposure device which can be applied to an opening of the plastic preforms in order to fill them with the flowable medium to apply. Furthermore, a valve device is provided which controls the application of the flowable medium to the plastic preforms.

According to the invention, the valve device has a first tubular body through which the flowable medium - in particular under a predetermined pressure - can be guided in a predetermined direction of movement, as well as a carrier which is movable with respect to this tubular body, a direction of movement in which the carrier is movable relative to the tubular body, encloses an angle different from 0 degrees with the predetermined flow direction and wherein the carrier has at least one first opening and wherein the carrier can be positioned in at least two positions relative to the tubular body, the tubular body in one position is (essentially) closed by the carrier and in the other position the flowable medium can be guided through the first opening.

Essentially closed is understood to mean that the tubular body is closed in particular apart from possible leakages.

In contrast to the prior art, a valve device is therefore proposed in which the valve is not closed and opened by the usual pistons or valve tappets, but by a carrier which is movable with respect to an outlet opening of the valve and which is in particular in a direction perpendicular to the flow direction of the gaseous or flowable medium standing direction is movable.

The carrier thus serves to switch the at least one valve device. The carrier is preferably used to switch several valve devices, as will be described in more detail below.

In a further advantageous embodiment, the blow mold has a plurality of parts which can be moved relative to one another for opening and closing the blow mold. The blow mold particularly preferably has two side parts and a bottom part, which can be moved relative to one another for opening and closing the blow mold.

The side parts are particularly preferably arranged at least indirectly on a blow mold carrier. A first side part can be arranged on a first blow mold carrier and a second side part on a second blow mold carrier. By moving these blow mold carriers relative to one another, the blow mold can be opened and closed. It is possible here for the side parts to be arranged directly on the blow mold carrier, but it would also be possible for the side parts to be arranged on the blow mold carrier parts via carrier shells.

The side part supports (with the blow molded parts arranged thereon) are particularly preferably pivotable with respect to an axis which is parallel to a longitudinal direction of the plastic preforms to be expanded.

In a further advantageous embodiment, the flowable medium is a gas and in particular compressed air. However, the use of a liquid would also be conceivable, as stated above.

In a further advantageous embodiment, the reshaping device has a rod-like body which can be inserted into the interior of the plastic preforms in order to stretch them in their longitudinal direction. This can in particular be a so-called stretching rod.

In a further advantageous embodiment, the application device is a blow nozzle. It is particularly preferable for this application device to be able to be advanced onto the plastic preform to be expanded. More precisely, the impingement device can be placed against an opening of the plastic preform in a particularly sealing manner.

The plastic preform is particularly preferably subjected to at least two pressures. For example, pre-blowing and final blowing can take place. In addition, it is also possible for the plastic preforms to be relieved and, in particular, for the compressed air to be released from them again.

In a further advantageous embodiment, the shaping device has a valve housing in which the valve device is arranged. The tubular body is particularly preferably movable with respect to this valve housing and, in particular, can be moved along a straight direction. This is explained in more detail below.

In a further advantageous embodiment, the device has a locking device in order to lock the blow piston in one position and, in particular, in a position applied to the plastic preform. This lock can also have a spring load.

In a further advantageous embodiment, the tubular body is a valve insert and, in particular, a valve insert which is introduced into the valve housing.

Particularly preferably, these tubular bodies and in particular these valve inserts have a wear-free material and / or they consist of a low-wear material. The valve inserts or the tubular bodies are particularly preferably made of a plastic.

These tubular bodies preferably contact the movable support. It is conceivable that these tubular bodies contact the movable carrier and / or at least one surface of this movable carrier over the entire circumference, that is to say over the entire circumference with regard to a tubular cross section.

As mentioned above, the direction of movement of the carrier is particularly preferably formed at an angle different from 0 degrees with respect to the tubular body or the direction of flow of the flowable medium through the tubular body. This angle is preferably greater than 30 degrees, preferably greater than 45 degrees, preferably greater than 50 degrees, preferably greater than 60 degrees, preferably greater than 70 degrees and particularly preferably greater than 80 degrees.

As mentioned above, this angle is particularly preferably approximately 90 degrees.

In a preferred embodiment, the carrier is rotatable with respect to a rotatable axis of rotation. It is therefore proposed that the carrier, which is used to open and close the valves, is rotatable about an axis of rotation.

The carrier is therefore preferably also rotatable with respect to the at least one tubular body. Both the tubular body and the carrier preferably form part of the valve device. Preferably, the tubular body and the support cooperate to achieve a closed position and an open position of the valve device.

The invention is also based on the consideration that when a plurality of valves are used here, only exactly one valve is open and the others are closed during a forming process. This enables the use of the rotatable valve body which, depending on the position, opens individual valves and closes others at the same time.

In addition, the invention preferably makes use of the fact that the same sequences of pressures are always used during the expansion process and / or the individual valves are always switched in the same sequence.

Thus, the carrier can preferably be rotated further in a specific direction of rotation during the blow molding process in order to reach the desired valves one after the other.

Storage devices are particularly preferably provided which rotatably support said carrier. These bearings can be roller bearings, for example. In a further advantageous embodiment, the carrier can also have a coating and be designed to be wear-resistant.

In a further preferred embodiment, a volume flow of the flowable medium can be influenced and in particular throttled by a movement of the support relative to the tubular body and / or depending on a position of the support relative to the tubular body. In particular, a flow cross-section of the flowable medium can be changed by a relative position between the carrier and the tubular body.

In a further advantageous embodiment, the axis of rotation extends parallel to a longitudinal direction of the plastic preforms to be expanded. Particularly preferably, the axis of rotation also extends parallel to a stretching rod which can be inserted into the plastic preform. It is possible that the axis of rotation of the carrier coincides with an axis of symmetry of this stretching rod.

The axis of rotation of the rotatable carrier is preferably also parallel to a longitudinal direction of the tubular body or a tube axis.

Therefore, as will be explained in more detail below, a valve block with a disk-shaped valve rotor is provided.

In a further advantageous embodiment, the carrier is therefore designed in the form of a disk. The carrier is particularly preferably designed as a circular disk. This disk can be rotated with respect to the valve inserts or the tubular body described in more detail below in order to close, open or even partially open them.

In a further advantageous embodiment, the carrier has at least one channel for guiding the flowable medium. This channel can preferably be implemented in the interior of said carrier. This channel preferably also extends in a radial direction of the carrier. This channel can also extend in the longitudinal direction of the plastic preforms to be expanded.

Furthermore, this channel can have a cross section that changes along its direction of extension.

This channel can lead the flowable medium, for example, to an annular channel or ultimately also to the application device or the blow nozzle.

In a further advantageous embodiment, the carrier extends around the longitudinal direction of the plastic preforms and / or an axis of symmetry of the stretching rod.

In a further advantageous embodiment, the shaping device has a second tubular body through which the flowable medium can be guided in the predetermined flow direction. Particularly preferably, the flowable medium can also be guided through this second tubular body in a direction which is parallel to the longitudinal direction of the plastic preforms.

This second tubular body is also particularly preferably designed as a valve insert which is arranged — preferably movably — in the valve housing.

In a further advantageous embodiment, the second tubular body is offset from the first tubular body. This can be arranged in the carrier at a different position. It is also possible that, depending on the rotational position or movement position of the carrier, this second tubular body is also closed, opened or also partially opened.

The rotatable carrier thus preferably cooperates both with the first tubular body and with the second tubular body. The rotatable carrier preferably forms a first valve device with the first tubular body and a second valve device with the second tubular body.

The device preferably also has a third tubular body which can also either be closed or opened by the carrier. In a further advantageous embodiment, the device also has a fourth such tubular body. The carrier thus also forms a valve device with the third tubular body and / or with the fourth tubular body.

Particularly preferably, the plurality of tubular bodies are arranged one after the other in a circumferential direction such that the predetermined pressures can be applied to the plastic preform by moving the carrier in a specific direction of movement and in particular a specific direction of rotation.

It is preferably possible here for at least two tubular bodies to have different flow cross-sections. These tubular bodies can be used to act on the plastic preforms at the different pressure levels (pre-blow pressure, intermediate blow pressure, finish blow pressure). Relief of the plastic preform is also possible with such a tubular body.

It is also possible and preferred that not only the respective valve devices can be switched between a closed position and an open position by a relative movement between the carrier and the tubular body, but that partially open positions of the valve devices are also possible, for example when the Cross section of the tubular body is only partially covered by carrier.

In a further advantageous embodiment, the device has reservoirs or the storage devices for the flowable medium. In this case, for example, annular channels can be provided which are suitable and intended for applying compressed air and a suitable pressure to the plastic preforms. The flowable medium can be stored in these reservoirs, in particular under different pressures.

In a further advantageous embodiment, the shaping device has a drive device and in particular an electromotive drive device for moving the carrier and in particular for rotating the carrier. This can in particular be a direct drive, that is to say the rotatable carrier can be arranged directly on the rotor of an electric motor.

This drive device can particularly preferably have a cooling device. The drive device particularly preferably has a liquid-based cooling device, for example in the form of one or more coolant channels which extend through a section of a housing of this electric motor.

The valve housing preferably has cooling bores.

In a further advantageous embodiment, the drive device is a servomotor. This can then move to specific positions in a targeted manner in order to determine the pressure level in the interior of the plastic preform relatively precisely.

In a further advantageous embodiment, the shaping device has an annular channel for receiving the flowable medium. In this way, this ring channel can extend around the stretching rod and receive the air thereof regardless of a rotational position of the rotatable carrier.

This annular channel can in turn be in flow connection with the loading device.

In a further advantageous embodiment, the device has a detection device for detecting a rotational position of the carrier. This detection device is particularly preferably a contactless detection system and in particular a contactless transmitter system. For example, a magnetic tape can be attached to the rotor and a sensor device can detect the position of these magnets.

A mechanical connection between the stretching rod and the actual blow piston, on which the valve device is also arranged, is particularly preferably provided. In particular, a surface and in particular a conical surface on which the stretching rod can engage can be attached to an inner diameter of the blow piston. Thus, the lowering stretching rod can also urge the blow piston (which is driven in particular by a spring device, such as a pneumatic spring) downwards. A stop is particularly preferably provided, which defines a lower position of the blow piston.

In a further advantageous embodiment, at least one tubular body or one of the valve inserts mentioned is pretensioned with respect to the carrier by means of a spring device. Preferably, several of the tubular bodies are prestressed with respect to the carrier, particularly preferably around all tubular bodies. This suspension device can in particular, but not exclusively, be a spiral spring or the like. In this way, a seal between the tubular body and the carrier is promoted.

In a further advantageous embodiment, the device has a locking device in order to lock the blow piston or the impingement device in a position in which it is advanced towards the plastic preform. It is possible, for example, for this locking mechanism to have a pawl which can be inserted into a corresponding groove on the blow piston. A mechanical entrainment element is particularly preferably provided, which brings about this locking in particular as a function of a position of the rotor.

In a preferred embodiment, the carrier is movable in a longitudinal direction with respect to the plastic preform to be expanded.

The present invention is further directed to a device for shaping plastic preforms into plastic containers with a movable and in particular rotatable main carrier on which a plurality of shaping devices of the type described above are arranged. This is advantageously a so-called blowing wheel, in which the individual forming stations are arranged. This rotatable carrier thus functions as a transport device that transports the plastic preforms along a specified transport path.

In a preferred embodiment, the device has at least one reservoir for storing a flowable medium and in particular for storing compressed air. This reservoir can preferably be designed in the form of an annular channel. Furthermore, this reservoir can be able to supply all of the shaping devices with the flowable medium.

The device preferably has at least two and preferably a multiplicity of such reservoirs. These reservoirs are particularly suitable and intended for holding the flowable medium under different pressures.

In a particularly preferred embodiment, these reservoirs are at least temporarily in flow connection with the tubular bodies or valve inserts with regard to the flowable medium.

The present invention is further directed to a method for reshaping plastic preforms into plastic containers. The plastic preforms are expanded within a blow mold, which forms a cavity, by being exposed to a flowable medium, whereby an impacting device is applied to an opening of the plastic preforms to apply the flowable medium to them, and a valve device is used to apply the plastic preforms to the fluid medium controls.

According to the invention, the valve device has a first tubular body, through which the flowable medium is guided in a predetermined flow direction, as well as a carrier which is moved with respect to this tubular body, a direction of movement in which the carrier is moved relative to the tubular body includes an angle different from 0 degrees with the predetermined flow direction, and wherein the carrier has at least one first opening, and wherein the carrier is moved in at least two positions relative to the tubular body, wherein in one position the tubular body is closed by the carrier (so that the flowable medium is prevented from flowing further) and in the other position the flowable medium is guided through the first opening.

The application device is preferably a blow nozzle or the application device has a blow nozzle.

In terms of the method, a procedure is therefore also proposed in which a movable carrier is moved in a direction of movement which includes an angle different from 0 degrees with the direction of flow of the flowable medium, in relation to the tubular body, in order to convert the valve formed in its entirety into a bring closed or open position.

In a preferred embodiment, the application device is pressed against an opening of the plastic preforms in order to apply compressed air to them. This pressing is preferably carried out under a certain force, this force being able to be generated, for example, by a pretensioning device, by a drive or also by the compressed air itself.

In a further preferred method, the plastic preform is subjected to different pressure levels, these different pressure levels being caused by different movements of the carrier (in particular by the fluidic connection of different tubular bodies with the opening in the carrier.

In a further preferred method, the movement of the carrier is a rotary movement. However, it would also be possible for the movable body to be moved other than by a rotary movement, for example by a linear movement.

The flowable medium is preferably passed through a plurality of tubular bodies, the individual tubular bodies being closed in particular sequentially by the carrier. Preferably, for a certain period of time, the flowable medium ultimately only passes through one of the tubular bodies into the plastic preform.

Particularly preferably, the rotatable carrier is rotated in only one direction of rotation at least temporarily during the process. The rotatable carrier is particularly preferably then rotated in the opposite direction in order to continue the process.

In a further preferred method, the plastic preforms are stretched in a longitudinal direction by means of a stretching rod. The movement of the valve device (in particular in the longitudinal direction of the plastic preforms) is advantageously coupled at least temporarily to the movement of this stretching rod.

Further advantages and embodiments emerge from the accompanying drawings.

• 1 eine schematische Darstellung einer Vorrichtung zum Umformen von Kunststoffvorformlingen zu Kunststoffbehältnissen;
• 2 eine Schnittdarstellung eines Details einer erfindungsgemäßen Umformungseinrichtung;
• 3 eine Detaildarstellung der in 2 gezeigten Schnittdarstellung;
• 4 a, 4 b zwei weitere Schnittdarstellungen in zwei verschiedenen Positionen der Beaufschlagungseinrichtung;
• 5 a, 5 b zwei Darstellungen eines Verschließzustandes des Blaskolbens für die erfindungsgemäße Vorrichtung;
• 6 eine Darstellung der einzelnen rohrförmigen Körper;
• 7 a bis 7 i Positionen des Trägers in verschiedenen Verfahrensstadien;
• 8 a bis 8 f weitere Positionen des Trägers in einem weiteren Verfahrensabschnitt.

Show in it:

• 1 a schematic representation of a device for reshaping plastic preforms to plastic containers;
• 2 a sectional view of a detail of a forming device according to the invention;
• 3 a detailed representation of the in 2 sectional view shown;
• 4 a , 4 b two further sectional views in two different positions of the loading device;
• 5 a , 5 b two representations of a closed state of the blow piston for the device according to the invention;
• 6th a representation of the individual tubular body;
• 7 a to 7 i Positions of the carrier in different process stages;
• 8 a to 8 f further positions of the carrier in a further process section.

1 shows a schematic representation of a device 60 for forming plastic preforms into plastic containers. The device has a rotatable main carrier 5 on which a variety of conversion equipment 1 are arranged. Plastic preforms are attached to this carrier or to the individual shaping devices 10 fed. These become plastic containers and especially plastic bottles for the forming devices 20th reshaped and from the device 60 discharged.

2 shows a detailed view of a forming device according to the invention 1 . This has in particular a valve device 4th , such as a so-called valve block in particular 4th . The valve block has a valve rotor executed carrier 50 on, which is the above-mentioned movable, in particular, rotatable carrier. This carrier 50 is driven by a direct drive.

For this purpose is a stator 24 provided, as well as a rotor 26th , which is rotatable with respect to the stator. It is preferred here that an axis of this motor and also an axis of rotation of the carrier 50 coincide.

It can also be seen that in the valve housing 30th Coolant holes 32 are provided. This direct drive can optionally be water-cooled, which leads to higher performance with a compact design.

There is a pneumatic spring on the top of the valve block 66 arranged which the blow piston or the valve of this housing 30th moved downwards in its entirety. A conical surface on which the stretching rod or a stretching rod section can engage is attached to the inner diameter of the blow piston. In this way it can be achieved that the lowering stretching rod is affected by the pneumatic spring 66 driven blow piston drives down until a stop 68 prevents further movement.

In this position the loading device lies down 6th to the plastic preform. In this in 2 situation or position shown (this is the covering position or contact position on the plastic preform 10 ) the blow piston is locked.

The reference signs 42 and 44 characterize the tubular body or the valve inserts which are provided within the housing. By means of these tubular bodies, the flowable medium can pass through the carrier 50 or a channel 56 that is inside the carrier 50 is arranged in the direction of an annular channel 62 be transported. Starting from this ring channel, the flowable medium can turn to the loading device 6th to get redirected.

The reference signs S. mark the direction of flow of the flowable medium within the tubular body. This direction of flow is here preferably parallel to the longitudinal direction L. the plastic preforms. The direction of movement of the carrier is here a rotational movement perpendicular to the plane of the figure and thus this movement is also perpendicular to the direction of flow S

The reference signs 64 identify optional radial seals. The reference number 22nd identifies a stretching rod which is inserted into the plastic preforms 10 is insertable.

3 shows a detailed representation of the in 2 device shown. Here are the tubular bodies again 42 and 44 recognizable. It can be seen in particular that these are valve inserts which, with respect to the valve housing, are provided by a spring device 43 and 45 downwards, i.e. in the direction of the wearer 50 are biased.

The reference number 74 identifies a magnetic strip, which is here on an outer circumference of the carrier 50 is arranged. The reference number 72 identifies a sensor device which is used here as a detection device or as a rotary encoder. These elements are thus components of a detection device for detecting a rotational position of the carrier 50 here

The 4a and 4b identify the device according to the invention or the valve device once in a raised position ( 4 a) and once in one on the plastic preform 10 created lower position. The reference signs 82 , 84 , 86 and 85 identify the components of a locking system 80 . This locking system 80 serves to lock the blow piston or the valve device in a position in which it rests against the plastic preform. There is a locking element in the form of a pawl 82 provided, which in a locked state in a circumferential recess 86 can intervene.

This is done by the rotation of the motor of the locking element 82 activated that in said recess or groove 86 engages on the blow piston. As mentioned above, the locking element is a pawl that can be moved linearly here or rotated around a pivot point. The pawl is by a driver 85 operated on the rotor 26th is appropriate.

As mentioned above, there are cylindrical valve inserts in the valve housing 42 , 44 attached that on the carrier 50 or seal its surface and, in particular, seal it flat. These valve cores 42 and 44 are preferably in turn sealed radially to the valve housing. These valve inserts are preferably circular around the valve rotor and / or around the stretching rod 22nd arranged around. The orientations of the central axes of these valve inserts or of the tubular bodies are preferably parallel to a central axis of the carrier 50 .

These valve inserts are preferably made from a wear-resistant plastic with good sliding properties. This could be PTFE or graphite, for example. The valve rotor or carrier 50 is preferably designed with a low-friction wear layer.

The valve rotor also has an opening 52 on, which is preferably separated into two areas by a web. The cross-sectional opening of one of the two areas is arrow-shaped or conical so that a flow cross-section (which results from the overlap of this opening with the respective valve insert and the arrow-shaped opening) and thus also the volume flow can be set through the angular position of the valve rotor. This way the wearer can 50 act together with the tubular bodies as a proportional valve.

The axial through-opening is then guided radially inwards (cf. 3 ). Ultimately, as mentioned above, this channel goes into the ring channel 62 (compare 2 ) about.

The channel is preferred 56 designed aerodynamically. About the ring channel 62 the blown air flows into the openings of the blower piston. However, it would also be possible for the ring channel to be omitted. The radially inwardly guided channel can be used here 56 open directly into the openings of the blow piston.

For this purpose, it is advantageous if the blow piston is installed in the correct position, that is, in particular, secured against rotation. The openings on the blow piston are advantageously made in accordance with the angular position of the individual valve inserts (and thus the pressure levels).

In this way, a further reduction in dead space can be achieved. The valve inserts or tubular bodies are preferably with the two springs 43 and 45 biased. The ring surface facing away from the sealing surface can act as a piston surface. When the pressure increases, the contact pressure and sealing force can also increase.

The side facing the sealing surface is preferably provided with a shoulder. The force on this piston surface counteracts the attack force.

The ratio of these two areas is preferably selected such that the required application and / or sealing force is achieved and an excessively large frictional force (a resulting drive torque) is avoided. The valve insert or the tubular body for the pre-blowing pressure is preferably designed to be smaller with regard to its diameter and without the shoulder on the side facing the sealing surface. In cooperation with the arrow-shaped opening on the carrier 50 the proportional valve function can be implemented during pre-blowing. The valve block can optionally also be designed with several intermediate blowing stages (one, two or more). All valve functions are preferred exclusively with the drive motor 24 , 26th controlled.

The motor is preferably designed as a servomotor, so that the movement profile can be implemented variably. The individual valve opening times can thus be controlled via the speed profile. In particular, a pre-blow proportional valve function can be controlled via a speed profile and the resulting variable throttle cross-section.

The 5a and 5b show two representations of the locking mechanism. Here is the latch 82 shown which in the recess 86 engages in the locked state. Next to it is a groove 84 shown, which cooperates with the projection so as to also the feed movement of the pawl element into the recess during a rotary movement of the rotor 86 to reach. 5b accordingly shows an open position and 5a a closed or locked position of the blow piston.

6th shows a schematic representation of a plurality of tubular bodies or valve inserts. Here is a valve core 44 intended for the pre-blow pressure. Two tubular bodies 46 and 48 are for an intermediate blowing pressure level PI ( 1 ) and PI ( 2 ). The reference number 42 indicates a valve insert or a tubular body for the blowing pressure or final blowing pressure P2 . The reference number 41 identifies a valve insert or tubular body for an outlet or to release the air from the manufactured container.

The reference number 47 identifies a central opening through which, for example, the stretching rod (not shown) can be passed.

The 7a to 7i show a first sequence for a method according to the invention. The position of the valve inserts or tubular body is off again 6th shown and next to it the opening 52 in the carrier 50 , where in the 7a to 7i this carrier is rotated clockwise.

At the in 7a In the position shown, the blow piston is unlocked, but the blow nozzle may already have been placed on the plastic preform. At the in 7b The situation shown, the blow piston is locked, and that is in particular locked in a position in which the blow nozzle is seated on the plastic preform. The reference number 52 again indicates the opening in the carrier.

At the in 7c The situation shown is the opening in the relief position, that is, the plastic preform could be relieved.

The 7d to 7f show a pre-blowing of the plastic preform. The opening moves 52 about the in 6th tubular body shown 44 . Due to the relative movement, which in the 7d to 7f is shown, the function of the valve as a proportional valve can also be illustrated.

The rotational movement of the carrier 50 can be done intermittently. It is possible that the opening 52 briefly stops at the individual switching positions (or the individual tubular bodies) and then starts moving again. Preferably, however, the speed of rotation is only decelerated at the switching positions, so that the acceleration torque is reduced.

The 7g shows the situation of a first intermediate blowing. Here is the opening 52 above or adjacent to the tubular body 46 arranged so that over the tubular body 46 through the opening 52 the blown air can be guided. The 7h Fig. 13 shows a state of a second intermediate blowing in which the opening 52 on the tubular body 48 is arranged.

7i finally shows the state of finish blowing in which the opening 52 on the tubular body 42 is arranged, and in this way the compressed air for the finish blowing is supplied to the container.

The 8a to 8f show the opposite path that occurs after the container is expanded. These configurations also serve in particular to recycle blown air. At the in 8a The situation shown is the opening again at the tubular body 48 arranged so that a recycling of blown air can take place in the intermediate blower duct.

In this context, it should be stated that the pressures change and become greater in the individual stages for expansion of the plastic preform. In this way, it is possible for the higher pressures to be recycled into the ring channels provided for the lower pressure levels.

In 8a the higher pressure levels are recycled into the ring channel for the intermediate blowing. At the in 8b The situation shown is in the channel for the intermediate blowing 1 recycled and at the in 8c The situation shown is recycled into the ring channel for the pre-blowing process. At the in 8d The situation shown is relieved because this is the opening 52 on the tubular device or the valve insert 43 is applied. The direction of flow of the air is in the opposite direction.

At the in 8e The blow piston remains locked. At the in 8f the situation shown, the blow piston is unlocked again, and the process here is complete. In addition, the finished container can be removed from the forming device.

The applicant reserves the right to claim all features disclosed in the application documents as essential to the invention, provided that they are new to the state of the art, individually or in combination. It is further pointed out that features have also been described in the individual figures, which can be advantageous in themselves. The person skilled in the art immediately recognizes that a certain feature described in a figure can also be advantageous without the adoption of further features from this figure. Furthermore, the person skilled in the art recognizes that advantages can also result from a combination of several features shown in individual or in different figures.

List of reference symbols

1

Forming device

4th

Valve device

5

Main carrier

6th

Loading device

10

Plastic preform

20th

Plastic container

22nd

Horizontal bar

24

stator

26th

rotor

30th

Valve body

32

Coolant holes

42

first tubular body, valve insert

41

tubular body for exhaust

44

second tubular body

46.48

tubular body for intermediate blow pressure

43.45

Suspension device

47

central opening

50

carrier

52

Opening in the carrier

56

channel

60

Device for reshaping plastic preforms into plastic containers

62

Ring channel

64

radial seal

66

pneumatic spring

68

attack

72

Sensor device

74

Magnetic stripe

80

Locking system

82

Locking element, latch

84

Groove

85

Carrier

86

Recess

S.

Direction of flow

L.

Longitudinal direction of the plastic preform

P1

Pre-blow pressure

P2

Final blow molding

Pi (1)

first intermediate blowing pressure

Pi (2)

second intermediate blowing pressure

Ex

Exhaust, outlet

Claims (13)

Reshaping device (1) for reshaping plastic preforms (10) into plastic containers (20) with a blow mold which forms a cavity within which the plastic preforms (10) can be expanded by being exposed to a flowable medium, with an impacting device (6) which is attached to a mouth of the plastic preforms (10) can be placed in order to apply the flowable medium to them and with a valve device (4) which controls the application of the plastic preforms (10) with the flowable medium, characterized in that the valve device (4) has a has a first tubular body (42) through which the flowable medium can be guided in a predetermined flow direction (S), and a carrier (50) which is movable with respect to this tubular body, a direction of movement in which the carrier (50) is opposite the tubular body is movable with the predetermined flow direction encloses an angle different from 0 ° and wherein the carrier has at least one first opening (52) and wherein the carrier (50) can be positioned in at least two positions relative to the tubular body (42), in one position the tubular body (42) is closed by the carrier and in the other position the flowable medium can be guided through the first opening (52). Forming device (1) according to Claim 1 , characterized in that the carrier (50) is rotatable with respect to a predetermined axis of rotation (D). Forming device (1) according to Claim 2 , characterized in that the axis of rotation (D) extends parallel to a longitudinal direction of the plastic preforms (10) to be expanded. Reshaping device (1) according to at least one of the preceding claims, characterized in that a movement of the carrier (50) relative to the tubular body (42) and / or depending on a position of the carrier (50) relative to the tubular body, a volume flow of the flowable medium can be influenced and in particular throttled. Forming device (1) according to at least one of the preceding claims, characterized in that the carrier (50) is disc-shaped. Forming device (1) according to at least one of the preceding claims, characterized in that the carrier has at least one channel (56) for guiding the flowable medium. Forming device (1) according to at least one of the preceding claims, characterized in that the carrier (50) extends around the longitudinal direction of the plastic preforms (10). The shaping device (1) according to at least one of the preceding claims, characterized in that the shaping device (2) has a second tubular body (44) through which the flowable medium can be guided in a predetermined flow direction (S). The forming device (1) according to at least one of the preceding claims, characterized in that the forming device (2) has a drive device (24, 26) and in particular an electromotive drive device (40) for moving the carrier (50). The shaping device (1) according to at least one of the preceding claims, characterized in that the shaping device (1) has an annular channel (62) for receiving the flowable medium. Forming device (1) according to at least one of the preceding claims, characterized in that at least one tubular body (42, 44) is pretensioned with respect to the carrier (50) by means of a spring device (43, 45). Device for reshaping plastic preforms (10) into plastic containers (20) with a movable and, in particular, rotatable main carrier (5) on which a plurality of reshaping devices (1) according to at least one of the preceding claims is arranged. A method for reshaping plastic preforms (10) into plastic containers, the plastic preforms (10) being expanded within a blow mold which forms a cavity by being exposed to a flowable medium, wherein an impacting device (6) which is attached to an opening of the plastic preforms (10 ) is placed in order to apply the flowable medium to it and wherein a valve device (4) which controls the application of the flowable medium to the plastic preforms (10), characterized in that the valve device (4) has a first tubular body (42) through which the flowable medium is guided in a predetermined flow direction (S), as well as a carrier (50) which is moved relative to this tubular body, a movement direction in which the carrier (50) moves relative to the tubular body (42) is different from 0 ° with the specified flow direction encloses an angle and wherein the carrier has at least one first opening (52) and wherein the carrier (50) is moved in at least two positions relative to the tubular body (42), wherein in one position the tubular body (42) through the carrier ( 50) is closed and in the other position the flowable medium is guided through the first opening (52).

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