BLOW MOULDING MACHINE WITH CHANGING ROBOT AND GRIPPING DEVICE AND METHOD FOR OPERATION THEREOF

Description

[0001] The present invention relates to a device for forming plastic preforms into plastic containers. Such devices have long been known in the art.

[0002] WO 2012 / 120031 A1 and EP 2 292 402 A2 basically disclose the features of the generic terms.

[0003] Heated plastic preforms are typically formed into plastic containers such as plastic bottles by applying air pressure. For this purpose, a plurality of forming stations or blow molding stations are typically arranged on a rotating support. These blow molding stations each have blow molds with a cavity within which the plastic preforms are formed into the plastic containers. These blow molds thus have a negative of the container to be produced. If the device needs to be converted to other containers, the individual blow molds must be replaced. In the prior art, these blow molds are removed individually from the respective forming stations. An operator removes the individual blow molding devices and replaces them with new blow molding devices, which are intended to form the corresponding new containers.Therefore, the changing process takes a relatively long time and an operator is also necessary.

[0004] The present invention is therefore based on the object of simplifying such a changeover of blow molding machines. In particular, the corresponding changeover processes are to be accelerated.

[0005] These objects are achieved according to the invention by the subject matter of the independent claims. Advantageous embodiments and further developments are the subject matter of the dependent claims.

[0006] A device according to the invention for forming plastic preforms into plastic containers comprises a transport device that transports the plastic preforms along a predetermined transport path. The transport device comprises a movable station support arranged at least indirectly on a stationary base support, on which a plurality of forming stations are arranged. These forming stations each have blow molding devices that form cavities within which the plastic preforms can be formed into the plastic containers. These blow molding devices are each arranged on blow mold supports. These blow mold supports are preferably part of the individual forming stations and are thus preferably also arranged indirectly on the station support.

[0007] According to the invention, the device comprises a changing device which is suitable and intended to remove at least the blow-molding devices from their blow-molding carriers and / or to arrange blow-molding devices on the blow-molding carriers, wherein this changing device comprises a gripping device for gripping the blow-molding device, wherein this gripping device is movable in at least two different directions.

[0008] Therefore, within the scope of the invention, it is proposed that a gripping device be provided, which also serves, in particular, to grip the blow molding devices. This gripping device can be movable in two different directions, particularly in directions that are neither parallel nor opposite to each other.

[0009] Furthermore, according to the invention, the gripping device can be pivoted about at least three different axes.

[0010] Advantageously, the gripping device can be pivotable about more than three, preferably about at least four, preferably about at least five and particularly preferably about at least six pivot axes.

[0011] In a further advantageous embodiment, the gripping device is arranged on an arm pivotable about a predetermined first pivot axis. This arm is also referred to below as the second arm due to its arrangement in the changing device. The gripping device itself can also be pivotably or rotatably arranged on this arm.

[0012] In a further advantageous embodiment, the pivotable (second) arm is arranged on a further arm which can pivot about a predetermined second pivot axis. This further arm is also referred to below as the first arm due to its arrangement in the changing device. The first pivot axis is advantageously not parallel to the second pivot axis and particularly preferably skewed in the mathematical sense. Two degrees of freedom of movement of the gripping device can be achieved using these two axes alone. The gripping device is advantageously arranged pivotably on the second arm. This pivotable arrangement enables a further degree of freedom in movement. The gripping device can advantageously be pivoted about two axes relative to the second arm, for example about an axis which runs in the direction of this arm and also about an axis perpendicular to it.

[0013] Advantageously, the gripping device is arranged on the first arm so as to be pivotable with respect to at least two mutually perpendicular axes.

[0014] Preferably, at least one of these (geometric) pivot axes is stationary. This stationary pivot axis is preferably vertically oriented. Preferably, at least one axis is always arranged in a spatially fixed plane, i.e., regardless of the position of the changing device and / or the gripping device. This spatially fixed plane is preferably a horizontal plane. Preferably, at least two (pivot) axes are always arranged in a spatially fixed plane, i.e., regardless of the position of the changing device and / or the gripping device.

[0015] Preferably, at least one pair of (pivoting) axes is present, which are always perpendicular to each other, i.e., regardless of the position of the changing device and / or the gripping device. Preferably, the first arm is movable relative to a (particularly stationary) support with respect to these two pivoting axes.

[0016] Preferably, at least one further pair of (pivoting) axes is present, which are always perpendicular to each other, i.e., regardless of the position of the changing device and / or the gripping device. Preferably, the second arm is movable relative to the first arm with respect to these two pivoting axes.

[0017] Preferably, at least one further pair of (pivoting) axes is present, which are always perpendicular to each other, i.e., regardless of the position of the changing device and / or the gripping device. Preferably, the gripping device is movable relative to the second arm with respect to these two pivoting axes.

[0018] The arrangement of the (geometric) swivel axes described here is particularly suitable for enabling a high degree of freedom of movement of the gripping device.

[0019] Preferably, at least two pivot axes are always parallel to each other, ie independent of a position of the changing device and / or the gripping device

[0020] In a further advantageous embodiment, the gripping device has an engagement means for gripping at least one projection arranged on the blow molding device. Advantageously, the gripping device has two engagement means for gripping two projections arranged on the blow molding device. Such a projection can be arranged on each of two blow mold parts, and the gripping device can engage behind this projection during transport in order to hold the blow molding device together as a whole.

[0021] In a further advantageous embodiment, the second arm is pivotable relative to the first arm about at least two pivot axes. These pivot axes are advantageously perpendicular to each other.

[0022] In a further advantageous embodiment, the gripping device can be connected to the blow molding device in a form-fitting and / or force-fitting manner. This enables secure gripping and transport of the blow molding devices by means of the changing device, while also allowing transport at higher speeds.

[0023] In a further advantageous embodiment, the gripping device has a passive gripping element. This means, in particular, that the blow molding device is not held by an active gripping movement of the gripping element, such as a clamping movement, but rather solely by correctly positioning the gripping element or gripping device relative to the blow molding devices to be transported. In particular, an element of the gripping device can engage behind a section of the blow molding device.

[0024] It is also possible for the gripping device to have a magnetic or magnetizable element to hold the blow molding device. For example, the gripping device could have an electromagnet that can be activated as soon as the gripping device is in a predetermined position relative to the blow molding device. The gripping device could also trigger a magnetic hold between parts of the blow molding device.

[0025] According to the invention, the changing device comprises a control device that carries out the removal of the blow molding device from the blow mold carriers and / or the arrangement of the blow molding device on the blow mold carriers in a force- and displacement-controlled manner. Detection devices can be provided that detect movement, in particular of the gripping device, and detection devices for measuring forces can also be provided.

[0026] This control system defines one or more reference points on the blow molding station and / or the magazine that can be moved to. This also allows the precise geometric position of the blow molding device to be determined at any time during transport. Furthermore, it is preferred that the gripping device be deflectable in several degrees of freedom, for example, in the X, Y, and Z directions, particularly to compensate for positioning inaccuracies. However, it would also be possible for one or more of these degrees of freedom to be blocked electromechanically. This allows for faster operation of the device.

[0027] Advantageously, a detection device is provided which can detect the position or a deflection with respect to these degrees of freedom, preferably by querying them electrically, for example.

[0028] In a further advantageous embodiment, the gripping device comprises active elements that establish a positive and frictional connection with the blow molding device. It is possible for the gripping device to establish a positive connection between the two side parts of the blow molding device, and furthermore, preferably, a frictional connection is established between said blow mold halves and the base mold. This second connection with the base mold can be achieved via corresponding engagement elements of the side parts and / or the base mold.

[0029] In a further advantageous embodiment, the device, in particular the gripping device, has centering elements to enable precise positioning of the gripping device on the blow molding device or on the forming station. These centering elements can have insertion bevels, for example conical insertion bevels, with which the gripping device engages with corresponding elements on the forming station during the changeover process or contacts these corresponding elements. These corresponding elements are advantageously arranged on a mold carrier holder. In this way, the gripping device can be positioned relative to the blow molding device to be transported.

[0030] In a further preferred embodiment, the changing device is suitable and / or intended to change either a complete blow molding device or only (individual) parts of this blow molding device.

[0031] The embodiment proposed here is intended, on the one hand, to create the option of exchanging a complete blow molding device, which in particular has two side parts and a base part and is in particular composed of these parts. In this case, it is possible for the changing robot to grip the entire blow molding device and replace it with a blow molding device that is also complete and in particular also composed of these parts. In some cases, however, customers require different side parts to be used with an identical base part. In these cases, it can be helpful to only change the side parts or components of the blow molding device and not the base part, which is retained. If the entire blow molding device is changed in each case - as is normally the case - then the customers would also have to replace any (unnecessary orredundant) floor parts, which is sometimes not accepted.

[0032] In the embodiment proposed here, it is therefore suggested that, for example, only the side parts are exchanged by the exchange robot. Thus, the device is preferably designed in such a way that it is possible to either exchange the entire blow molding device (including its base part) or just the two side parts. Conversely, it would also be possible to exchange only the base part and retain one or two side parts.

[0033] It should be noted that this embodiment is also applicable without the invention described above, i.e., in particular, without the above-described features, according to which the gripping device is movable in at least two different directions and pivotable about at least three different pivot axes. The applicant therefore reserves the right to claim protection for a device according to the preamble of claim 1 and the additional feature mentioned here, according to which the changing device is suitable and / or intended to change either a complete blow molding device or only individual parts of this blow molding device.

[0034] In this case, the changing device should particularly preferably be designed to first remove the blow molding device in its entirety from the device and / or subsequently enable the separation of individual parts of the blow molding device. For example, it would be possible to remove the two side parts with a base part attached to them and then separate the base part from the side parts.

[0035] However, it would also be conceivable for the changing device to be designed in such a way that it only removes individual parts of the blow molding device from the respective blow molding station or forming station. This would make it possible for only one or two side parts of the blow molding devices to be removed from the respective blow molding station. For example, the side parts could be removed as a package, leaving a base part in the blow molding station during the changing process.

[0036] In a further advantageous embodiment, it is possible for the fastening mechanisms of the blow molding devices to be separated from those of a base part and / or activated or deactivated during a changeover process. For example, it would be possible for a fastening between one or both side parts and the base part to be activated and deactivated, allowing the side parts to be removed individually, for example.

[0037] In a further advantageous embodiment, it is possible for the base part to be held in the side parts during a changeover process by means of projections and, in particular, prisms, particularly preferably complementary prisms. These complementary projections or prisms can preferably also absorb the blowing force acting on the base part during the blowing process.

[0038] In a further advantageous embodiment, the gripping device itself enables the establishment and / or release of a mechanical connection existing between components of the blow molding device. In particular, the gripping device itself enables the establishment and / or release of a connection, in particular a mechanical one, existing between side parts of the blow mold and a base part of the blow mold. Thus, the changing device and / or the gripping device can have a first holding element for holding a first side part of the blow molding device and a second holding element for holding a second part of the blow molding device, and these two holding elements can be movable relative to one another, in particular for releasing a connection between the side parts and the base part. These two holding elements are advantageously movable relative to one another relative to a straight line.

[0039] Preferably, the gripping device can have at least one drive that causes a movement of at least one of these holding elements. This drive can be an electric, hydraulic, or pneumatic drive.

[0040] In an advantageous embodiment, the gripping element can move the two side parts of the blow-molding device essentially perpendicular to a longitudinal axis of the blow-molding device. This movement can separate the connection between the side parts and the base part.

[0041] In a further advantageous embodiment, the gripping device is designed such that it can move the two side parts of the blow molds apart and / or together relative to each other.

[0042] When changing only a few elements of the blow molding equipment, it is possible that a base part of the blow molding equipment is placed in one position and then reconnected or inserted with it when new side parts are inserted.

[0043] The present invention is further directed to a method for operating a forming device for forming plastic preforms into plastic containers. During operation of the device, the plastic preforms are transported along a predetermined transport path by means of a plurality of forming stations and expanded into the plastic containers by exposure to a flowable and, in particular, a gaseous medium. Furthermore, blow molding devices are used to expand the plastic preforms, within which the plastic preforms are expanded into the plastic containers. Furthermore, in an alternating operation, at least one of the blow molding devices is removed from the device and / or one of the blow molding devices is arranged on a blow mold carrier of the device.

[0044] According to the invention, a preferably automatically operating changing device is used to change the blow molding devices. This changing device has a gripping device for gripping the blow molding device, wherein this gripping device is movable in at least two different directions. The gripping device is preferably pivotable with respect to at least three, preferably with respect to at least four, pivot axes.

[0045] Preferably, a changing device of the type described above is used.

[0046] This changing device preferably has at least one pivotable changing arm and is arranged at least indirectly on the base support. It is therefore proposed to arrange a changing device, in particular in the form of a changing robot, directly in the area of the forming device. This device therefore advantageously has a base support, such as a machine frame, on which the station support is also arranged. The changing robot is, in turn, also arranged on this base support, so that it can be integrated into the machine as a whole.

[0047] A substantially indirect arrangement means that the changing device can be arranged directly on the base support, but it is also conceivable for the changing device to be arranged on another element, such as an intermediate support, which in turn is arranged on the base support. In principle, however, it would also be conceivable to arrange the changing device outside the support. For example, it would be conceivable to position the changing device outside the blow molding machine.

[0048] The invention thus proposes integrating the changing device or robot into the machine. Advantageously, the blow molding device is constructed in multiple parts and comprises at least two side parts and a base part. During operation, these three parts form the cavity for expanding the plastic preforms. Advantageously, at least two parts, and particularly preferably all three parts, of this blow molding device are interlockable with one another, so that the blow mold can be removed in its entirety from the machine or from the blow mold carrier. The blow mold carrier is thus suitable for accommodating different blow molding devices. It would be possible for the blow molding device itself to be attached to the blow mold carrier by means of carrier shells.

[0049] Advantageously, the blow mold carriers are movable and, in particular, pivotable relative to one another. During operation, the blow mold carriers can be pivoted apart by a predetermined angle to insert plastic preforms and / or remove finished containers. Larger opening angles are possible, preferably for alternating operation.

[0050] In a further advantageous embodiment, the forming stations each have stretching rods that can be inserted into the plastic preforms during operation to stretch them longitudinally. Advantageously, the individual forming devices also have pressurizing devices, which in particular have blowing nozzles, which, during operation, pressurize the plastic preforms with a flowable, and in particular a gaseous, medium. It would also be possible to replace other parts of the forming stations, such as, in particular, the pressurizing device or blowing nozzles and / or the stretching rods.

[0051] Advantageously, the station support is a rotatable support, such as a blowing wheel. The individual forming stations are preferably arranged on an outer circumference of this rotatable support. This allows the forming stations to move along a circular path during operation.

[0052] Advantageously, the device comprises a drive device for moving the station carrier. This drive device preferably enables both continuous movement of the station carrier and cyclic movement of the station carrier, which thus has rest phases between movements. This type of movement is advantageously adjustable depending on an operating mode. In a working mode, the station carrier is preferably moved continuously, and in an alternating mode, it is preferably moved cyclic. The movement of this station carrier can also be coordinated with the movements of the changing devices. The station carrier is advantageously a blowing wheel.

[0053] The procedure according to the invention enables a fully automatic changing process, in particular by means of an industrial robot. Advantageously, the blow molding device can be locked fully automatically, in particular in alternating operation, or the individual elements of the blow molding devices can be fastened to one another. The changing device is thus preferably suitable for gripping or removing the complete blow molding device, i.e. its at least three components as a whole. Advantageously, after gripping the blow molding device, a corresponding mold locking mechanism can be deactivated. In a further step, the changing device can deposit the mold assembly in a storage device, such as a magazine. The changing device can then insert a new mold assembly or a new blow molding device into a blow mold carrier and (preferably) lock the new blow molding device to the blow mold carrier.

[0054] The station carrier can then be moved one position further to exchange another blow molding device. This allows for a fully automated process without the need for a human operator.

[0055] In a further advantageous embodiment, the device comprises a housing that surrounds at least the station support in its circumferential direction. In principle, the entire blow molding device and / or the changing device can be arranged within a housing, whereby this housing can also have a protective function.

[0056] The changing device is preferably integrated directly into the machine and can, for example, be attached to a base frame. In a further advantageous embodiment, the changing device can be moved in its entirety within a space enclosed by the housing. In this case, it is possible for the changing device to be fully integrated into the machine during operation and thus, for example, not even be visible from the outside and, in particular, not to interfere with the operation of the forming device. It is possible for a casing of the housing to also serve as a protective device for the changing device or the robot. During operation, the said changing device is therefore preferably arranged within the housing.

[0057] In a further advantageous embodiment, the changing device comprises a first control device for controlling a removal movement of the blow molding devices and / or a feeding or arrangement movement for arranging the blow molding devices on the blow mold carriers, and the device preferably also comprises a second control device for controlling a blow molding process, wherein the first control device and the second control device interact at least partially and / or at least temporarily. In particular, these two control devices interact during a blow mold changing process. Thus, during a changing process, the same movements that are also necessary during operation can also be used for the changing process, such as, for example, the transport movement of the forming stations, the opening and closing of the blow mold carriers, and the like.

[0058] During the changeover process, the blow mold carriers can also be opened to allow the blow molding device to be removed. For example, the second control device can cause the blow mold carriers to open, and depending on this, the first control device can cause the blow molding devices to be removed. This also enables a fully automatic change of the blow molds. The control of the changeover device preferably interacts with the control device of the forming machine or blow molding machine.

[0059] In a further preferred embodiment, the changing device comprises a first control device for controlling a removal movement of the blow molding devices and / or the arrangement movement for arranging the blow molding device on the blow mold carriers and the device also comprises a second control device for controlling a blowing process, wherein one control device is integrated into the other control device.

[0060] In particular, the control of the changing device is integrated into the control system of the device or blow molding machine. This would make it possible for the changing device to be designed as a module, which can also be integrated into the blow molding machine in terms of control technology, for example after being plugged together or connected. It would also be possible for a changing device to be retrofitted to existing devices. These control devices can be designed in such a way that a protective zone is expanded during changing operation. During operation, the changing device can be in a rest position in which it poses no danger and in which it does not prevent operation of the machine.

[0061] During alternating operation, the switching device is also activated, so that those areas whose entry could potentially be dangerous for the user must be expanded. It is conceivable that, during alternating operation, modified protection areas may also be blocked off or at least made visible to the user.

[0062] It would be possible for additional protective elements to be activated during alternating operation, thereby increasing the safety of the operator.

[0063] In a further advantageous embodiment, the changing device has at least one gripping device for gripping the blow molding devices. This can be a gripping device that grips the blow molding device in its entirety. It would be possible for media and / or electrical signals required by the gripping device to be routed through areas of the changing devices, such as axes or pivot arms. It would also be possible for such connections to be routed via rotary unions, for example, on the axes of the changing devices.

[0064] In a further advantageous embodiment, the changing device has at least one detection device for detecting at least one force acting on an element of the changing device. In particular, external forces can act, for example, on a changing arm that removes the blow molding devices. In particular, the above-mentioned control device can be designed such that it can react to external forces, for example during defined operations such as setting down or picking up a blow molding device, the changing device can deviate from a desired position (soft float). In general, this is a detection device that can react to physical influences or can detect such influences, such as torque, forces, impulses or the like. In this way, a rapid reaction of the changing device is possible.

[0065] Preferably, however, the changing device moves within a limited working area. This means that, in particular, the removal and feeding movement for the blow molding devices also takes place within a limited working area. In response to the external forces mentioned above, a position may deviate from this working area. Otherwise, however, this defined working area is preferably maintained, especially during a mold change.

[0066] It is advantageous to limit the working area of the changeover device for safety reasons, especially mechanically. Such a limitation could be achieved through various measures, such as light barriers that detect incorrect or excessive movement of the changeover device and subsequently trigger either a reversal or an emergency stop of the changeover device. In addition, the working area could also be limited by mechanical elements, such as stops.

[0067] In addition, it is also preferably possible for a working area of the changing device to be checked for safety, electrical, or control-related aspects. In particular, it is possible for this working area to be (further) restricted from a maximum possible working area.

[0068] In a further advantageous embodiment, the changing device has serial and / or parallel kinematics with at least three axes of movement. Advantageously, the changing device has serial and / or parallel kinematics with more than three axes of movement. This allows for a very high degree of freedom of movement of the changing device or a gripping element of the changing device. Therefore, depending on the actual conditions, the blow molding devices can be removed from or added to their blow mold carriers in different ways.

[0069] It is possible for the device to have an operating device to control the changing device or gripper arm. This could, for example, be a handheld control unit. However, it would also be possible for the changing device to be controlled via devices such as smartphones.

[0070] Control by such an operating device is particularly advantageous during setup operation, i.e. when adding new blow molding devices.

[0071] The present invention is further directed to a method for operating a forming device for forming plastic preforms into plastic containers. During operation of the device, the plastic preforms are transported along a predetermined transport path by means of a plurality of forming stations and expanded into the plastic containers by exposure to a flowable and, in particular, gaseous medium. Furthermore, blow molding devices are used to expand the plastic preforms, within which the plastic preforms are expanded into the plastic containers. In an alternating operation, at least one of the blow molding devices is removed from the device and / or one of the blow molding devices is arranged on a blow mold carrier of the device.

[0072] According to the invention, a changing device arranged on the device is used to change the blow molding devices. Therefore, it is also proposed in the method that such blow mold changes be carried out by means of a changing robot arranged on the device or integrated into it.

[0073] In a further preferred method, the forming stations are transported along a circulating transport path during operation, and in the alternating operation, the blow molding devices are removed at a predetermined, fixed position relative to the circulating transport path of the respective forming station whose blow molding device is to be removed. It is therefore proposed that the forming stations rotate during operation, as is known per se in the prior art. For the individual changing process, however, it is proposed that this takes place at at least one precisely defined station, which in particular also lies within an effective range of the changing device. In other words, the removal position on a blow molding wheel is advantageously always identical. In this case, it is possible for the changing device to align itself during production or operation in such a way that it lies within a blow molding machine protection area orhousing can be arranged.

[0074] With regard to the control device, it is conceivable that it controls the movement sequence of the changing device or the robot via two independent coordinate systems. Preferably, one coordinate system is located at the removal or insertion position of the blow molding device to the forming station or the blow mold carriers. Another coordinate system can be located in the area of a receiving device or a magazine in which the blow molding devices are stored.

[0075] However, it is possible for the positions of the receiving points of the blow molding devices on the receiving device or the magazine to remain unchanged relative to its coordinate system, independent of the receiving device, and / or for the positions of the receiving points to be equidistant from this coordinate system. In this case, it is possible for a display device, such as in particular an input screen, to be provided on the changing device. This can be used to change certain values of the coordinate systems, in particular the X, Y, and Z values of the coordinate systems. In addition, a further input device, such as an input screen, can preferably be arranged on the changing device, which preferably interacts with an input device of the blow molding machine.

[0076] There are several possibilities for removing and feeding the blow molding equipment.

[0077] It would be conceivable that all blow molding equipment would first be removed from the individual mold carriers, i.e., the individual forming stations, and placed into an empty magazine or storage system. This storage system containing the old molds would then be replaced by a full storage system containing new blow molding equipment to be exchanged. All new molds would then be placed into the blow mold carriers. The storage systems could be changed, for example, using a pallet truck or turntables, similar to a pallet change on machine tools. In this case, the blow mold carrier would advantageously perform two complete revolutions for a complete change.

[0078] In another possible changeover process, a magazine contains an empty space. First, a new mold is placed from a mold location into this empty space. Then, an old mold is placed from the mold carrier into the said mold location. In a further step, a new mold is transferred from the magazine to the mold carrier. Subsequently, a second new mold is placed in the empty space, and so on until the entire changeover is complete. Intermediate storage in an empty space ensures that a specific blow molding device is returned to a specific storage location or a specific blow mold carrier. Advantageously, the said empty space is located between the blow mold carrier and the storage system and preferably on or in the storage system itself.

[0079] Advantageously, the removal of the blow molding device and / or the addition of new blow molding devices takes place in a cyclic operation. This means that the individual change of the blow molding device takes place while the forming station is at a standstill. The changing device can deposit a specific blow molding device in a magazine, while the forming device itself can move forward one station, i.e., the blowing wheel rotates one position. For inserting and removing the blow molding devices, a radial direction relative to the transport path is advantageously used. As mentioned above, it is also possible to park or set down the blow molding device in an intermediate station. A vertical movement is preferably used for this purpose.

[0080] In terms of the process, it is possible for the gripping device of the changeover device to positively grip the blow molding device in order to transport it or remove it from the device. Advantageously, the gripping device of the changeover device engages the blow molding device with a force fit.

[0081] In a further advantageous embodiment, the removal and / or depositing of the blow molding device is carried out in a path- and / or force-controlled manner and preferably both path- and force-controlled.

[0082] Within the scope of the control system, it is possible for the changing device to move to at least one defined reference point on the forming station or the receiving or blow mold carriers and / or preferably also at least one defined reference point at a storage location, such as a magazine. In this way, said points can be transferred to the control system of the changing device, whereby the exact positions of the mold receiving or blow mold carrier and also of the magazine or storage device can be determined. It is preferably possible for said reference points to be moved to after each exchange of a magazine device or also in the event of malfunctions, such as power failures, in order to be transferred to the control system.

[0083] It is possible for the reference points determined in this way to be saved and / or compared with reference points stored in the controller or a storage device of the controller. If a deviation occurs between the determined reference point and the previously saved reference point, particularly if it exceeds a predetermined value, an error message or a warning can be generated.

[0084] In a further advantageous embodiment, the changing device comprises an image recording device, such as a camera or the like. This camera device makes it possible to capture the precise pick-up and drop-off points for the blow-molding devices.

[0085] In this context, it is conceivable that the blow molding devices and / or the blow mold carrier and / or the magazine device each contain an identification to ensure the assignment between the blow molding devices and the respective blow molding station. This ensures that a specific blow molding device removed from a specific forming station is assigned to the same forming station upon subsequent changeover. This would make it possible for each receiving magazine to be assigned a unique identifier.

[0086] These markings can be, for example, barcodes, QR codes, RFID tags, and the like. It is advantageous for this marking to be read contactlessly. The marking, or a value characteristic of this marking, is advantageously transferred to the machine's control system.

[0087] Another possible approach is to reread the respective markings after each magazine change or in the event of a machine failure. This ensures reliable assignment even under exceptional circumstances.

[0088] A receiving device or magazine for the blow molding devices is described below. This receiving device can be arranged in a suitable position for a mold change, for example next to the forming device. The magazine or receiving device can have insertion areas via which the blow molding devices can be placed into the magazine or the receiving devices. These insertion areas can be conical to enable secure insertion of the blow molding devices. Advantageously, the blow molding device or the mold package is inserted essentially vertically into the magazine. Particularly preferably, the blow molding device can be placed in cylindrical openings in the magazine or the receiving device. The magazine itself can be arranged - in particular with a form-fitting fit - in this receiving device.

[0089] In a preferred embodiment, this magazine device can have elastic elements, particularly in the region of the cylindrical openings, for inserting the blow molding devices in order to be able to compensate for tolerances.

[0090] In a further advantageous embodiment, it would also be possible for the magazine or receiving device and / or the blow-molding device to be equipped with insertion areas, and in particular with conical insertion areas, in the areas in which the blow-molding device comes into contact with the cylindrical openings of the magazine device.

[0091] In a further advantageous embodiment, as mentioned above, the magazine or receiving device has a plurality of openings for receiving the individual blow molding devices. These openings are advantageously cylindrical. Particularly preferably, these openings in the magazine devices are made of plastic, at least in some areas.

[0092] It is possible for these openings to be arranged in several rows, with two adjacent rows, for example, being offset from each other. This allows the packing density of the blow molding devices to be increased.

[0093] In a further advantageous embodiment, the position of the blow molding device within the receiving device is lower than the position of the blow molding device in the blow mold carrier. This allows the blow molding device to be lowered downwards during disassembly.

[0094] In a further advantageous embodiment, the magazine has a polygonal and preferably rectangular outer contour, with the longitudinal side of this outer contour preferably being arranged substantially perpendicular to an imaginary radial connecting line between a pitch circle center and the blow mold carriers. In this way, the magazine device can be very easily reached by the changing device or an arm of the changing device.

[0095] The design of the blow molding device is described below. It is conceivable that, for unlocking the blow molding devices on a mold carrier or a mold carrier shell, or for unlocking a base part of the blow molding device, the assembly, i.e., in particular, the side parts and the base part, are mechanically connected to one another. However, a magnetic connection could also be considered.

[0096] Such a fixing mechanism, which connects the individual blow mold parts to one another, is advantageously designed in such a way that it exerts or exerts a force only in one tensile direction and has a certain degree of radial flexibility to compensate for tolerances. Advantageously, a projection, a cam, or the like can be provided on the parts of the blow molding devices, such as the blow mold halves, which can be engaged behind by an element of the gripping device or into which the gripping device can retract.

[0097] In a further advantageous embodiment, the projections or cams associated with a gripping device are advantageously arranged radially within the pitch circle defined by the container center. This ensures that these cams cannot come into contact with clamps, for example, of an infeed and outfeed starwheel, even during operation.

[0098] In a further advantageous embodiment, it would also be possible to have a positive connection between the two mold shells and a base mold of the blow molding device, which prevents the base mold from twisting relative to the side parts or mold shells. It would also be possible for the base mold to be mechanically connected to the mold halves before the changeover process.

[0099] To simplify the loading and unloading process, it would be possible for a rotation axis of the blow molding device to run essentially parallel to the axis of the mold carrier or to a rotation axis of the blowing wheel during loading and unloading (of the plastic containers).

[0100] In a further advantageous embodiment, it would also be possible for a protective area of the blow molding machine to be automatically separated from a storage area of the blow molds or blow molding devices during production. Such a separation can be carried out automatically at the beginning or start of a mold change process—in particular automatically.

[0101] The protection zones can be modified so that a machine operator can access an area of the mold storage area during production of the device or during operation. For example, it would be conceivable for an electromechanical unit to secure the position of a forming station relative to the changing device, preferably by positive and / or force locking, after positioning the blowing wheel.

[0102] Furthermore, it would also be conceivable for the robot to place the blow molding unit or the mold package from an intermediate position into the magazine while the blowing wheel moves one cycle forward or brings a subsequent forming station into a changeover position. In addition, the general procedure for changing a blow molding unit could involve moving to an intermediate station where the blow molding unit is temporarily parked or deposited. In this case, the holding device does not need to be designed as a double gripper, and station-specific allocation of the molds in a storage device such as a magazine is still possible.

[0103] As already mentioned above, it can be advantageous if the opening movements of the blow mold carrier and the base in a changeover position for the blow molding device differ from those during operation. This can be advantageous, for example, with a non-coupled mold carrier control. It would also be possible for a blow mold carrier of the adjacent station, which is leading or lagging in the blow molding device changeover position, to also be partially pivoted away in order to allow a larger opening angle for the forming station in the changeover position.

[0104] Furthermore, it would be possible for a locking mechanism for the shell molds and the base molds to exhibit a progressive characteristic during a clamping cycle. At the beginning of such a clamping cycle, a large stroke can be applied with a low force to bridge the largest possible gaps during retraction. Towards the end of the clamping cycle, a large force is preferably applied with only a small stroke.

[0105] In a further advantageous method, the changing position of the blow molding station and / or the magazine and / or any intermediate position in which the blow molding devices are temporarily positioned is located in a predetermined circumferential area of an effective circle of the changing device, preferably in a area of 270° of the effective circle, preferably in a area of 220° of the effective circle and particularly preferably in a area of 180° of the effective circle.

[0106] In a further advantageous method, the changing device or the changing robot performs a radial movement relative to the pitch circle of the device when removing and / or placing the blow molding device from the stations or on the blow mold carriers. This can be a purely radial movement, but it is also conceivable for it to be a movement with a radial component.

[0107] In a further advantageous method, the changing device or the changing robot performs a substantially vertical movement when removing and / or placing the blow molding device from the stations or on the blow mold carriers. "Substantially" means that the direction of movement deviates from the exact vertical direction by no more than 20°, preferably by no more than 10°, and particularly preferably by no more than 5°.

[0108] In a further preferred method, components of at least one blow molding device are separated from one another during a changeover process. Separation during the changeover process refers to the entire changeover process, i.e., the entire period between the removal of one blow molding device and the installation or assembly of another blow molding device in a blow molding station. In this embodiment, preferably, the entire blow molding device is not removed, but rather only its components, for example, the side parts, are replaced.It is thus possible to first remove an entire assembled blow moulding device, then separate the side parts of this blow moulding device from the base part of this blow moulding device, then use new side parts which in turn are connected to the original base part and then mount the reassembled blow moulding device on the blow moulding station.

[0109] It should be noted again that this variant, namely the separation of components of the blow molding device during the changeover process, can also be used independently of the method described above, i.e., independently of the pivotability of the gripper arm. The applicant therefore reserves the right to claim protection for a method according to the preamble of the independent method claim, which is characterized by the separation of components of the blow molding device during the changeover process.

[0110] Preferably, at least one component of the blow molding device is not replaced during a corresponding replacement process. In particular, at least one side part of the blow molding device is replaced during at least one replacement process, but not a base part.

[0111] In a further method, it would also be conceivable for the blow molding station to be controlled during a changeover process in such a way that a connection between the side parts and the base part can be actively severed, at least temporarily. With this embodiment, it would be possible for the base part to be removed separately from the side parts, in particular by a linear movement (and preferably a movement in a longitudinal direction of containers to be expanded), in order to then only pick up the side parts. In this case, it would be possible, for example, for the blow molding device still arranged at the forming station to be opened (as is also possible during operation), then the base part to be moved away, then the blow molding device to be closed again and dismantled in this closed state (but without the base part).

[0112] In a further advantageous method, it is also possible for the blow molding device to be controlled during the changeover process in such a way that the connection between the side parts and the base part can be actively separated, at least temporarily. It would be possible to have active connecting elements directly in the blow molding device to accommodate only the molded parts. Furthermore, it would be possible for these active coupling elements to be addressed or activated for the entire changeover process.

[0113] In a further preferred method, it is possible for a base part of the blow molding device to be moved, and in particular rotated, particularly for a changeover process, and thereby the connection between the side parts and the base part can be actively separated, at least temporarily. For this purpose, the centering devices of the base parts can have a toothing to accommodate (only) the side parts.

[0114] In a further advantageous method, it would be conceivable that a base part is removed and "parked" before the side parts are changed, in particular with a gripping device, so that the side parts do not have to be changed when they are subsequently changed.

[0115] Further advantages and embodiments can be seen from the attached drawings.

[0116] Showing: Fig. 1A schematic representation of a device according to the invention; Fig. 2A representation of the device with the changing device shown; Fig. 3A plan view of the Fig. 2 shown device; Fig. 4 a further illustration of the device shown in Fig. 2 shown device; Fig. 5 a further illustration of the device shown in Fig. 2shown device in a further operating position; Fig. 6 a representation of a forming station; Fig. 7 a representation of a mold shell for a blow molding device; Fig. 8 a representation of a changing device; Fig. 9 a representation of a gripping device for gripping a blow molding device; Fig. 10 a representation of a changing device with a blow molding device; Fig. 11 a representation to illustrate possible positions of the changing device; Fig. 12 a representation of a magazine with a blow molding device; Figs. 13a - 13h representations to illustrate a partial change of a blow molding device; Figs. 14a,b two representations of a gripping device; and Fig. 15a,b respectively further representations of a gripping device.

[0117] Fig. 1shows a schematic representation of a device 1 for forming plastic preforms into plastic containers. The plastic preforms 10 are fed to the individual forming stations 8 and expanded into plastic containers 20. After this expansion, the plastic containers are removed from the device. For this purpose, a feed star can be provided, which feeds the plastic preforms to the device 1 and to a discharge device, in particular also a transport star, which discharges the finished containers from the device. The device 1 has a station carrier 12, on which a plurality of forming stations 8 are arranged. This station carrier can, for example, as in Fig. 1As shown, a blowing wheel can be rotatable relative to a rotational axis D (which here runs perpendicular to the plane of the figure and thus vertically). Each individual forming station has a blow molding device 14. This blow molding device 14 consists of two side parts and a base part. These blow molding devices can be replaced according to the invention. The blow molding devices 14 are arranged on blow mold carriers 16 and can be removed from them or arranged on them.

[0118] Reference numeral 40 denotes a changing device, which serves to remove the blow molding devices from their blow mold supports or to arrange the blow molding devices on the blow mold supports. Reference numeral 6 denotes a base support on which the station support 12 is rotatably mounted. The changing device 40 is also arranged on or next to the base support 6. This allows the changing device 40 to be integrated into the device. Reference numeral 18 denotes a housing, which at least partially surrounds the station support 12, but which can preferably also enclose or house the changing device 40, as shown below.

[0119] The reference symbol W denotes a changeover position. As mentioned above, the blow molding devices are preferably changed over at a specific changeover position. This means that the forming stations can be successively moved to this changeover position W by rotating the carrier 12. The old blow molding devices can then be removed from this changeover position and, preferably, new blow molding devices can also be added. The reference symbol R denotes a radial direction. In this radial direction, the changing device or a gripping device of the changing device is preferably advanced toward the forming stations or the blow molding devices in order to change them.

[0120] Fig. 2shows a perspective view of a device 1, wherein only a forming device or forming station 8 is shown here. The station support on which this is arranged is also not shown here. However, the base support 6, on which the changing device 40 is arranged, can also be seen. This changing device 40 has a first pivotable arm 56 and a second pivotable arm 54. These two arms are pivotally connected to one another via an articulated and drive connection.

[0121] Reference numeral 52 denotes a gripping device used to grip and transport the blow molding devices. This gripping device is pivotably mounted on the second arm 54 and is preferably also rotatable. Thus, the gripping device can be pivoted in space about at least three, preferably at least four, axes. In addition, it would also be possible, as shown by the dashed rectangle, to provide several changing devices, each of which is arranged at least indirectly on the base support 6. In this way, the individual blow molding devices could be exchanged more quickly in alternating operation.

[0122] Reference numeral 46 schematically denotes a detection device that detects forces acting on the changeover device 40 or the gripping device 52, respectively, so as to be able to shut them down in an emergency. Advantageously, the device comprises several such detection devices, each of which is preferably assigned a separate drive device that causes the changeover device 40 or the gripping device 52 to move. These detection devices can, for example, be force measuring devices that determine actual forces, torques, and the like. However, it would also be possible for the forces to be determined from parameters of the respective drive, such as currents or the like.

[0123] Reference symbol B denotes a user who operates the system. This user can advantageously not move into areas that can be reached by the changing device 40 during operation of the changing device.

[0124] Reference numeral 22 denotes a control device for controlling the changing device. Reference numeral 42 denotes a control device for controlling the forming device itself. These two control devices can interact with each other, particularly for alternating operation for exchanging the blow molding devices. It is possible for the changing device 40 to move into a rest position during normal operation of the device, in which the changing device occupies as little space as possible.

[0125] Fig. 3 shows a top view of the Fig. 2 It can be seen here that the changing device 40 is also integrated into the housing 18. In the Fig. 3 In the state shown, the arm 56 is just swung out so that the gripping device 52 can just grip a blow molding device.

[0126] Also shown is a magazine device 70, which has a plurality of receiving locations 72 for receiving the blow molding devices. These blow molding devices can be inserted into the receiving locations or holes 72.

[0127] Fig. 4 shows a further illustration of the device according to the invention. It can be seen that a wall 32 is provided here, which separates the user B from the changing device 40 so that he or she cannot be injured. In addition, further movable wall parts 34 can also be provided, so that, on the one hand, the machine is more easily accessible for maintenance purposes, or, on the other hand, further changing devices can be provided, as also shown in Fig. 1 shown.

[0128] The Fig. 5 The illustration shown is similar to that in Fig. 3shown illustration, but here the changing device 40 is in a different operating position. This can, for example, be a working operation in which the device converts plastic preforms into plastic containers. It can be seen that a recess 18a can be arranged in the housing 18, which also serves to completely accommodate the changing device 40. In the Fig. 5 In the state shown, the individual arms of the changing device 40 can be folded in such a way that the changing device 40 takes up only a small amount of space.

[0129] Fig. 6shows a representation of a forming station 8. The blow mold carrier 16 can be seen here, which can have two blow mold carrier parts 16a, 16b that can be pivoted apart to open and close the blow molding device 14. The two blow mold carrier parts 16a, 16b can also be pivoted apart for alternating operation in order to remove the blow molding device 14.

[0130] Reference numeral 82 denotes in its entirety a locking device which, during operation, locks the two blow mold carrier parts 16a and 16b together so that they do not swing apart even under greater pressure. Reference numeral 66 refers to a projection which is arranged on each of the two side parts of the blow molding device 14. This projection is designed to be so stable that the entire blow molding device 14 can be supported by this projection. This projection 66 can be gripped behind by the gripping device or a component of the gripping device, so that the gripping device 52 can support the blow molding device via this projection. By holding the respective side parts of the blow molding device on the projections 66, the blow molding device as a whole can also be held together.

[0131] Fig. 7denotes a blow mold carrier shell. This blow mold carrier shell 15 can be arranged on the blow mold carrier 16 and, in turn, can accommodate the blow molding device or parts of the blow molding device. Feed and discharge elements 15a can be provided to supply media, such as temperature control media, to the blow mold shell 15.

[0132] Fig. 8 shows a further illustration of the changing device 40. Here, the first arm 56 is again shown, which is pivotable about a first axis A1. In addition, however, this arm 56 is also rotatable about a second axis A2. A second arm 54 is arranged on this first arm 56, and the arm 54 is pivotable relative to the first arm 56 with respect to an axis A3. Here, the two axes A1 and A3 are parallel to one another. However, these axes can also be arranged obliquely or skewably to one another. In addition, the second arm 54 is also rotatable about a fourth axis A4.

[0133] To achieve this respective pivoting and rotating movement with respect to the individual axes and also with respect to the other axes yet to be described, drive devices are provided, such as in particular, but not exclusively, electric motor drives. In addition, the use of pneumatic and / or hydraulic drives would also be conceivable. A gripping device 52 is provided on the second arm 54 and serves to grip the blow molding device. This gripping element is pivotable relative to the arm 54 with respect to an axis A5. This axis A5 can be perpendicular to the axis A3 and / or perpendicular to the axis A4. In addition, the gripping device is arranged on the arm 54 via a support 58. The gripping device itself can in turn be rotatable relative to this support 58 with respect to an axis A6.

[0134] By means of this multitude of movements, the blow molding devices 14 can be removed from the individual forming station and placed on a carrier 74, which is shown here as a Euro pallet. However, it would also be possible to insert the blow molding devices 14 directly into designated openings of a magazine.

[0135] The distance between the magazine device or pallet 74 and the changing device 40 can be between 1 and 2 meters. The corresponding operating radius of the changing device can also be in the range of 1.5 meters.

[0136] Fig. 9shows a detailed view of the changing device 40 and its gripping device 52. This gripping device can have a guide element 62, which can be guided over a corresponding surface of the blow molding device. In addition, projections 64a, 64b can also be provided, which serve to center the changing device 40, or more precisely, the gripping device, relative to the forming station. Reference numeral 63 refers to a recess arranged in the guide element 62, which can engage behind the projections for changing the blow molding device. Thus, the guide element 62 also serves to support the blow molding device 14.

[0137] Fig. 10shows a representation of the changing device with a blow molding device 14 arranged thereon. It can be seen that the gripping arm 52 engages in two projections 66 arranged on the blow molding device 14 and presses them together, so that in this way the blow molding device is held together. In this way, the Fig. 9 and Fig. 6 shown projections 66, which are arranged on the blow molding device 14, for holding the same together during its transport. Thus, the gripping device 52 advantageously engages above the blow molding device 14 in elements of the same in order to hold them. This type of engagement in the blow molding device is particularly suitable since the blow molding device, as in Fig. 6shown, protrudes beyond its support and can thus be gripped even when the blow mold support 16 is closed. This makes it possible for the changing device or robot to first grip the blow mold device 14 via its projections 66 and only then open the blow mold support. This ensures that the blow mold device is held securely at all times.

[0138] Fig. 11shows a further illustration of the present invention. Here, several changing devices 40a - 40d are provided, each of which can be used to change elements of the device. For example, it would be possible for two of the changing devices (40a, 40b) to be provided to change blow molding devices 14, but also for further changing devices to be provided to change other elements, such as heating mandrels located in a furnace 50 for heating the plastic preforms (the changing device 40d). In addition, the changing device 40c shown can also be used to change, for example, holding elements such as transfer tongs, which transport the plastic preforms to the forming device 1 after they have been heated.

[0139] Fig. 12shows a receiving device such as a magazine for receiving the blow molding devices 14. This can contain a carrier plate 75, which has a plurality of openings 77. By means of supports 78, this plate 75 can be arranged on a base support 79, wherein this base support 79 in turn has openings 79a or holes for receiving the blow molding devices. Advantageously, this magazine has the same dimensions as a so-called Euro pallet and thus preferably dimensions in the range of 1200 x 800 mm. The individual openings 79a are, as in Fig. 12 shown, arranged in rows and offset from each other so that the largest possible number of blow molding devices can be inserted into the pallet.

[0140] The Figures 13a - 13h illustrate a changeover process for a blow molding device, where not the entire blow molding device is to be changed but only its side parts. Figure 13a In the illustration shown, a complete blow molding device 14 is arranged on a gripping device 52. Here, the gripping device 52 removes the entire blow molding device, ie both the two side parts 14a and 14b as well as the base part 14c, which is mechanically coupled to the side parts 14a and 14b, from the blow molding machine. In a further step, the entire blow molding device 14 is placed or arranged on a storage location (not shown) for the base part 14c. In a further process step, the gripping device 52 opens, as in Figure 13d shown. For this purpose, two holding elements of the gripping device 52, explained in more detail below, can be pushed apart in order to also move the two side parts 14a and 14b apart.

[0141] At the Figure 13cIn the situation shown, the gripping device 52 moves upwards with only the side parts 14a and 14b still attached to it. The base part 14c remains in its storage location. Figure 13d In the situation shown, the two side parts 14a and 14b are placed in a corresponding storage area (not shown). Furthermore, as in Figure 13e shown - new side parts 14a and 14b taken from the (not shown) stock. Figure 13f In the situation shown, these two side parts are moved apart again and, with the gripping device opened accordingly, placed over the old base part 14c. This situation is also shown in Figure 13g shown. In this situation, the two side parts 14a and 14b were moved downwards, and when the gripping device 52 is subsequently closed, the old base part is picked up by the two blow mold side parts 14a and 14b.

[0142] Finally, the new side parts 14a and 14b as well as the original bottom part 14c can be reattached to a mold carrier (not shown) as shown in Figure 13h illustrated.

[0143] The Figures 14a and 14b show a representation of a gripping device, which is also suitable and intended to move the two side parts apart in order to release the base part. Figure 14a a top view of the gripping device and Figure 14ba view from below. It can be seen that this gripping device 52 again has the two guide elements 62, in which the recesses 63 (for receiving the projections 66 arranged on the side parts) are arranged. However, while in the embodiment shown above this guide element 62 was formed in one piece, two such guide elements 62 are now provided, which can be moved apart. For this purpose, these guide elements 62 (and thus also the recesses 63) are each arranged on a carrier 102 via a carriage 104 and can be moved relative to this. The reference numeral 120 refers to a first drive device in order to Figure 14a shown left guide element and the reference numeral 130 refers to a drive device to move the Figure 14aguide element 62 shown on the right. Reference numerals 122, 124, 132 and 134 indicate communication connections for connecting a hydraulic or pneumatic medium. Figure 14b Retaining elements 142 are shown for attaching the gripping device 52 to an arm. In addition, further connections 152, 154 for hydraulic or pneumatic means are provided to enable further degrees of freedom of movement, such as pivoting of the guide elements 62 as a whole or even linear displacements.

[0144] In the Figures 15a and 15b In the embodiments shown, the guide elements 62 are set apart or away from each other. Accordingly, the side parts, whose projections rest in the recesses 63, are also set apart, so that - as described with reference to the Figures 13a - 13h explained - the base part can now be removed from the side parts.

[0145] Thus, in this embodiment, the gripping device 52 enables a relative movement between the guide elements 63 and the holding elements 62, which serve to hold and guide the side parts 14a, 14b of the blow-molding device 14. The two guide elements 62 are each movable along a linear direction in order to move the side parts of the blow-molding device away from each other or toward each other.

[0146] As mentioned above, the drives used to move the side panels apart and together are preferably pneumatic. Standard magazines can be used as storage units for the blow molding equipment. List of reference symbols

[0147] 1 Device / forming device 6 Base support 8 Forming stations 10 Plastic preforms 12 Station support 14 Blow molding device 14a, 14b Side parts of the blow molding device 14c Bottom part of the blow molding device 15 Blow mold shell 15a Supply and discharge element for tempering medium 16 Blow mold support 16a 16b Blow mold support parts 18 Housing 18a Recess 20 Plastic containers 22 Control device for controlling the changing device 32 Wall 34 Wall parts 40 Changing device 40a-40d Changing device 42 Control device for controlling the forming device 46 Detection device 50 Furnace 52 Gripping device 54 Second pivoting arm 56 First pivoting arm 58 Support 62 Guide element 63 Recess 64a, 64bProtrusions 66Protrusions 70Magazine device 72Holes 74Carrier / pallet 75Carrier plate 77Openings 78Carrier 79Bottom support 79aOpenings / holes 82Locking device 120,130Drives 122, 124Communication connections 132, 134Communication connections 142Holding elements 142,154 connections, DRotation axis BUser A1 - A6Axes WChange position Rradial direction

Claims

1. Apparatus for forming plastic preforms (10) into plastic containers (20), having a transport device (2) which transports the plastic preforms (10) along a predetermined transport path, wherein the transport device (2) having a movable station carrier (12) which is arranged at least indirectly on a stationary base carrier (6) and on which a plurality of forming stations (8) are arranged, these forming stations (8) each having blow-molding devices (14) which each form cavities, within which the plastic preforms (10) can be formed into the plastic containers and these blow-molding devices are each arranged on blow-molding carriers (16), and the apparatus (1) has a changing device (40) which is suitable and intended for removing at least the blow molding devices from their blow molding carriers (16) and / or arranging blow molding devices on the blow molding carriers (16), wherein this changing device (40) having a gripping device (52) for gripping the blow molding device (14), wherein this gripping device (52) being movable in at least two different directions and pivotable about at least three different pivot axes (A1, A2....A6), wherein the changing device has a control device which carries out a removal of the blow molding device from the blow molding carriers in both a force-controlled and a displacement-controlled manner, and / or carries out an arrangement of the blow molding device on the blow molding carriers in both a force-controlled and a displacement-controlled manner, characterized in that the control device is set up in such a way that this control makes it possible to define one or more reference points at a blowing station and / or a magazine which can be approached, and the control device is set up in such a way that the exact geometric position of the blow molding device can be determined at any time.

2. Apparatus (1) according to claim 1, characterized in that the reference points are approached after each exchange of a magazine device or the event of faults in order to be transferred to the control system.

3. Apparatus (1) according to claim 2, characterized in that the reference points determined in this way are stored and / or compared with reference points stored in the control unit or a storage device of the control unit.

4. Apparatus (1) according to claim 3, characterized in that an error message can be generated if there is a deviation between the determined reference point and the already stored reference point that exceeds a predetermined level.

5. Apparatus (1) according to at least one of the preceding claims, characterized in that the gripping device (52) has an engagement means (62, 63) in order to grip at least one projection (66), in particular a cam, arranged on the blow moulding device (14), in particular to grip behind said projection, into which the gripping device (52) can be retracted, in particular wherein the projection (66) is set up and provided for centring the gripping device (52) relative to the forming station (8).

6. Apparatus (1) according to the preceding claim, characterized in that the projection (66) is arranged within a pitch circle described by a container center.

7. Apparatus (1) according to claim 1, characterized in that the changing device moves to at least one defined reference point on the forming station or the blow mold carriers and / or at least one defined reference point on a magazine device.

8. Apparatus (1) according to at least one of the preceding claims, characterized in that the changing device is suitable for changing either a complete blow molding device or only parts (14a, 14b, 14c) of the blow molding device (14).

9. Apparatus (1) according to claim 8, characterized in that the gripping device (52) makes it possible to establish and / or release a connection existing between components (14a, 14b, 14c) of the blow molding device.

10. Method for operating a forming device (1) for forming plastic preforms (10), according to at least one of the preceding claims, into plastic containers (20), wherein in a working operation of the device (1) the plastic preforms (10) are transported along a predetermined transport path by a plurality of forming stations (8) and are expanded into the plastic containers (20) by being acted upon by a flowable medium, wherein blow molding devices (14) are used for expanding the plastic preforms (10), in the interior of which the plastic preforms (10) are expanded into the plastic containers (20), wherein at least one of the blow molding devices (14) being removed from the apparatus (1) and / or one of the blow molding devices (14) being arranged on a blow mold carrier (16) of the apparatus (1) in a changing operation, and a changing device (40) is used for changing the blow molding devices (14), which has a gripping device (52) for gripping the blow molding device (14), wherein this gripping device (52) being movable in at least two different directions and pivotable with respect to at least three pivot axes (A1, A2,....A6), wherein the changing device has a control device which carries out a removal of the blow molding device from the blow molding carriers in both a force-controlled and a displacement-controlled manner, and / or carries out an arrangement of the blow molding device on the blow molding carriers in both a force-controlled and a displacement-controlled manner, characterized in that the control device is set up in such a way that this control makes it possible to define one or more reference points at a blowing station and / or a magazine which can be approached, and the control device is set up in such a way that the exact geometric position of the blow molding device can be determined at any time.

11. The method according to claim 10, characterized in that two blow mold carrier parts (16a, 16b) of a blow mold carrier (16) are pivoted apart in order to open the blow molding device (14) and then the blow molding device (14) is removed during a changing operation.