DEVICE FOR PRODUCING CONTAINERS FROM PREFORMS MADE OF THERMOPLASTIC MATERIAL

Description

[0001] The invention relates to a device for producing containers from preforms made of thermoplastic material.

[0002] To manufacture containers, particularly plastic containers, processes can be used that transform preforms by blow molding or hydraulic forming. Rotary machines are used for large-scale production. With the rotary machines, a large number of plastic preforms are transferred one after the other to a large number of molding devices that are connected to a rotor section of the rotary machine, e.g., a blowing wheel or a filling wheel. To transfer the preforms to the rotary machine or to remove the containers from the rotary machine, the containers or preforms can be gripped or made available using gripping devices. The gripping devices grip the containers or preforms in their neck area. For this purpose, the gripping devices are displaced radially relative to the rotor section.

[0003] EP 2 114 804 B1 discloses a rotary machine in which tongs are attached to support arms. The support arms are designed to be telescopic. Using cam tracks, the support arms are telescopically extended and retracted in a radial direction, so that the tongs attached to them are also extended and retracted. The support arms feature linear plain bearings or lubricated rolling element linear guides. Furthermore, the support arms can be pivoted about a vertical axis. The pivoting movement is also controlled by the cam tracks.

[0004] From DE 10 2014 005321 A1, a device and a method for transporting and handling containers, in particular containers made of a thermoplastic material, are further known, wherein the containers are transported by the transport device in a transport direction from an input point to an output point, wherein the transport device has at least one handling device moving in the transport direction for, in particular, simultaneously handling one or more of the containers, and wherein the handling device is arranged to be movable relative to the transport device for movement in a direction deviating from the transport direction, wherein the transport device has at least one motor by means of which the at least one handling device can be moved by motor in the direction deviating from the transport direction.

[0005] Furthermore, from US 2013 / 0062163 A1 a device for transporting hollow bodies is known, comprising the following: at least one element for gripping a hollow body, wherein the element has at least one cam follower made of an electrically conductive material; at least one fixed cam intended to engage with the cam follower, wherein the cam is made of an electrically conductive material; a contact layer made of an electrically insulating material and arranged between the cam and the cam follower; wherein the cam follower is connected to a first electrical signal, while the cam is connected to a second electrical signal, wherein an element is positioned to detect the electrical contact between the cam follower and the cam.

[0006] DE 10 2013 014618 A1 discloses a synchronous operation safety device for transfer stations for devices for handling containers, in particular for handling bottle-like containers made of glass or plastic, comprising a first and a second rotating element, each of which is provided with receiving elements for the container and each having a motor drive, wherein the rotating elements are arranged relative to one another such that the containers can be transferred from one of the first receiving elements to one of the second receiving elements in a transfer area. It has been shown that the rotating elements each have a control element with engagement elements that are connected for rotation, that the control elements are in meshing engagement with one another, wherein the control elements are arranged such that, during operation, they are in contactless engagement during the rotational movement of the rotating elements and that, in the event of a fault, they are in contacting engagement.

[0007] The object of the invention is to provide a device for producing containers from preforms made of thermoplastic material which are more cost-effective and meet increased hygiene requirements.

[0008] The problem is solved by the features of the independent claims. Advantageous further developments are the subject of the dependent claims and the following description.

[0009] In a device for producing containers from preforms made of thermoplastic material, wherein the device comprises at least one transport device with at least one transfer unit for moving containers and / or preforms between a first transfer position and a second transfer position, wherein the transfer unit has a gripping element for holding a container and / or preform, it is provided according to the invention that the transfer unit has a transfer arm to which the gripping element is connected and which is mounted on the at least one transfer unit in a contactless manner.

[0010] According to the invention, a wear- and lubricant-free movable bearing of the transfer arm on the transfer unit of the device for producing containers from preforms is provided. The transfer arm with the gripping element is mounted on the transfer unit in a contactless, movable manner. The contactless, movable bearing of the transfer arm prevents abrasion. Furthermore, no lubricants such as oil or grease are required for the movement of the transfer arm. This prevents contamination of the containers or preforms or the subsequent contents of the containers, so that increased hygiene requirements can be met. Furthermore, the maintenance of the transfer arm is simplified, thus saving costs.

[0011] It is conceivable that the transfer arm can be mounted on the at least one transfer unit in a contactless manner by means of a linear guide element.

[0012] This allows a linear movement of the transfer arm to be carried out, whereby the transfer arm can carry out a telescopic movement in conjunction with the linear guide element.

[0013] According to one example, the linear guide element can comprise a rail element and a carriage element mounted on the rail element in a contactless manner, in particular with air bearings, magnetic bearings or hydrostatic bearings, which is movable along the rail element and connected to the transfer arm.

[0014] This provides an effective and simple, low-maintenance linear guide for the transfer arm. In the example of a hydrostatic bearing, this can be water-based. The device can then further include a water return.

[0015] Furthermore, the transfer arm can be mounted on the at least one transfer unit in a contactless manner, for example by means of a pivot bearing, in particular with air bearings, magnetic bearings or hydrostatic bearings.

[0016] This allows the transfer arm to pivot, whereby the transfer arm can be connected to the at least one transfer unit via the pivot bearing. In the example of a hydrostatic bearing, this can be water-based. The device can then further include a water return.

[0017] In a further example, the device may comprise a compressed air source connected to the transfer unit via a compressed air connection, wherein the transfer arm is air-mounted on the at least one transfer unit.

[0018] If the container manufacturing equipment forms the containers using blast air, a compressed air source can be used as the blast air supply unit. In this case, retrofitting non-contact pivot bearings can be simplified.

[0019] It is also conceivable that the transfer arm can be connected, for example, to a linear drive unit for moving the transfer arm.

[0020] This eliminates the need for a cam control for moving the transfer arm in the radial direction relative to the rotor section. This allows the device to be manufactured with less effort.

[0021] The invention is described below using an exemplary embodiment with the aid of the accompanying drawings. They show: Figure 1 is a schematic representation of an apparatus for producing containers from preforms of thermoplastic material; and Figure 2 is a schematic representation of a transfer unit.

[0022] According to Figure 1 The device for producing containers from preforms made of thermoplastic material is designated in its entirety by the reference numeral 10 below.

[0023] The device 10 comprises a feed device 12 for feeding preforms made of thermoplastic material, a transport wheel 14, a heating section 16 for thermally conditioning the preforms, a first transport device 24, a forming device 18 and a second transport device 26.

[0024] The preforms fed by the feed device 12 are picked up by the transport wheel 14 and transported to the heating section 16. The preforms then pass through the heating section 16, where they are thermally conditioned for the forming process in the forming device 18.

[0025] After passing through the heating section 16, the preforms are transferred to a first transfer position on a first transport device 24, which can be configured as a transfer wheel. The transport device 24 has a plurality of transfer units 28 with which the preforms can be picked up at the first transfer position. Each transfer unit 28 can be moved between the first transfer position and a second transfer position.

[0026] At the second transfer position, the transfer units 28 place the preforms into molds 22 of the molding device 18. In the molds 22, the preforms are expanded into containers. The molds 22 can be attached to a wheel 20, which rotates about a rotational axis.

[0027] After forming, the containers are removed from the molds 22 by a second transport device 26. For this purpose, the second transport device 26 also has a plurality of transfer units 28.

[0028] The containers are removed at a first transfer position of the second transport device 26. At a second transfer position of the second transport device 26, the containers can be transferred to further devices by the transfer units 28.

[0029] In Figure 2A first transport device 24 is shown, whereby the second transport device 26 can be designed analogously. The features of the first transport device 24 described below can therefore also be part of the second transport device 26.

[0030] The transport device 24 has at least one transfer unit 28. The transfer unit 28 comprises a gripping element 36 and a transfer arm 30. The gripping element 36 is connected to the transfer arm 30 and is designed to grip preforms or containers. For this purpose, the gripping element 36 can, for example, grip a neck region of the preforms or containers. For this purpose, the gripping element 36 can have clamp parts 38, 40, which are designed to grip a neck region of a preform or container by means of an active or passive clamping.

[0031] The transfer arm 30 is movably mounted on the transfer unit 28. The movable mounting of the transfer arm 30 is designed to be contactless.

[0032] The transfer arm 30 can perform a pivoting movement and a telescopic linear movement. The contactless bearing can affect only the pivoting movement, only the telescopic linear movement, or both types of movement. The transfer arm 30 can optionally also perform additional or alternative types of movement based on a contactless bearing.

[0033] In the Figure 2In the illustrated embodiment, the transfer arm 30 is mounted so as to be movable without contact both with respect to the pivoting movement and with respect to the linear telescopic movement. However, this does not preclude the possibility that the transfer arm 30 may be mounted so as to be movable without contact only with respect to the pivoting movement or only with respect to the telescopic linear movement.

[0034] With regard to the pivoting movement, the transfer arm 30 can be connected to a pivot bearing 34. The pivot bearing 34 is designed, for example, as an air bearing, magnetic bearing, or hydrostatic bearing. Alternative types of contactless bearings can also be provided. During a pivoting movement of the transfer arm 30, friction between solid materials on the pivot bearing 34 is thus largely avoided.

[0035] If the pivot bearing 34 is designed as an air bearing, for example, the pivot bearing 34 can have an air bearing bushing.

[0036] With respect to the linear telescopic movement, the transfer arm 30 can be attached to a linear guide element 32. The linear guide element 32 can be pivotally mounted on the pivot bearing 34.

[0037] The linear guide element 32 can have a carriage element 44 that is mounted contactlessly on a rail element 42. The carriage element 44 can be moved along the rail element 42. The transfer arm 30 can also be attached to the carriage element 44. A movement of the carriage element 44 along the rail element 42 thus simultaneously causes a movement of the transfer arm 30 along the rail element 42.

[0038] The non-contact bearing provided by the linear guide element 32 may include, for example, an air bearing, a magnetic bearing, or a hydrostatic bearing. Alternative types of non-contact bearings may also be provided.

[0039] With a telescopic linear movement of the transfer arm 30, friction between the solid materials of the bearing is largely avoided. This prevents abrasion and eliminates the need for lubricants for the bearing's operation.

[0040] If the contactless bearing of the transfer arm 30 is provided by means of an air bearing and the forming device 18 performs the forming of the preforms with blown air, the air required for the bearing can be provided by the same compressed air source 46 as the blown air. For this purpose, the compressed air source 46 can be connected to the transfer unit 28 via a compressed air connection 48. The blown air or compressed air can, for example, be used to provide an air bearing for the carriage element 44 on the rail element 42. Furthermore, the blown air or compressed air can be used to provide an air bearing on the pivot bearing 34.

[0041] The blowing air or compressed air can, for example, be provided at a pressure between 1 bar and 7 bar, preferably between 2 bar and 6 bar, more preferably between 3 bar and 5 bar, most preferably between 3.5 bar and 4.5 bar.

[0042] If non-contact bearings are provided by a hydrostatic bearing, water-based bearings can be provided. Water recirculation can also be provided.

[0043] Furthermore, the transfer unit 28 can have a linear drive unit 50. The linear drive unit 50 can be configured to move the transfer arm 30 in a linear direction. For this purpose, the linear drive unit 50 is connected to the transfer arm 30.

[0044] The linear drive unit 50 can thus move the transfer arm 30, for example, along the linear guide element 32. The movement can occur in both directions along the linear guide element 32. List of reference symbols

[0045] 10 Device 12 Feeding device 14 Transport wheel 16 Heating section 18 Molding device 20 Wheel 22 Mold 24 First transport device 26 Second transport device 28 Transfer unit 30 Transfer arm 32 Linear guide element 34 Pivot bearing 36 Gripping element 38 Gripping part 40 Gripping part 42 Rail element 44 Slide element 46 Compressed air source 48 Compressed air connection 50 Linear drive unit

Claims

1. Device for producing containers from preforms of thermoplastic material, wherein the device (10) comprises at least one transport device (24, 26) with at least one transfer unit (28) for moving containers and / or preforms between a first transfer position and a second transfer position, wherein the transfer unit (28) has a gripping element (36) for holding a container and / or preform, wherein the transfer unit (28) has a transfer arm (30) to which the gripping element (36) is connected, characterised in that the transfer arm (30) is mounted on the at least one transfer unit (28) so as to be movable without contact.

2. Device according to claim 1, characterised in that the transfer arm (30) is mounted on the at least one transfer unit (28) to be movable without contact by a linear guide element (32).

3. Device according to claim 2, characterised in that the linear guide element (32) has a rail element (42) and a carriage element (44) mounted on the rail element (42) in a contactless manner, in particular air-mounted, magnetically mounted or hydrostatically mounted, which carriage element is movable along the rail element (42) and is connected to the transfer arm (30).

4. Device according to one of claims 1 to 3, characterised in that the transfer arm (30) is mounted on the at least one transfer unit (28) to be movable without contact by a pivot bearing (34), in particular air-mounted, magnetically mounted or hydrostatically mounted.

5. Device according to one of claims 1 to 4, characterised in that the device (10) has a compressed air source (46) which is connected to the transfer unit (28) via a compressed air connection (48), the transfer arm (30) being air-mounted on the at least one transfer unit (28).

6. Device according to one of claims 1 to 5, characterised in that the transfer arm (30) is connected to a linear drive unit (50) for moving the transfer arm (30).