Clamping Apparatus, Winding Apparatus as Well as Unit

This application claims priority to German Patent Application Number DE 10 2024 117 565.6, filed Jun. 21, 2024, the entire contents of which is hereby incorporated by reference.

The disclosure relates to a clamping apparatus for clamping a winding core, a winding apparatus for winding and unwinding a flat material web as well as a unit for producing a material web.

In the production of material webs, for example plastic films, the produced material web, for example the film, is wound into winding bales on a winding core. Here, the length of the winding core must equal the width of the material web in order to be capable of winding the material web in one piece.

The advances in units for producing material webs has resulted in being capable of producing increasingly wider material webs so that the winding cores required for this purpose also are longer.

However, the total weight of a winding core comprising a completely wound-up winding bale is however also considerably greater due to the longer winding cores so that the requirements of the winding apparatuses increase.

Typically, the winding apparatuses comprise at least one receiving space with two clamping heads that engage with the face ends of the winding cores and clamp these. Typically, one of the clamping heads in the axial direction is stationary and the second one of the clamping heads is moveable. The stationary and thus compact clamping head is designed here on the operator side of the winding apparatus in order to impede the operator as little as possible when operating the winding apparatus.

As a result of the stationary clamping head, when inserting or removing a winding core in the winding apparatus, the winding core must be moved axially in order to engage the winding core with the fixed clamping head. This axial movement, however, results in axial forces acting on the winding apparatus or the support, particularly in the case of heavy winding cores, so that the support must be reinforced and enlarged. However as a result, the operator is impeded when operating the winding apparatus.

There is provided a clamping apparatus, a winding apparatus as well as a unit for producing a material web that is designed compactly on the operator side in the case of particularly long winding cores.

Provided is a clamping apparatus for clamping a winding core. The clamping apparatus has a base, a clamping head and a locking mechanism. The locking mechanism is adjustable between a lock position and a release position, and the clamping head is axially moveable relative to the base between an extended position and a retracted position. In the lock position, the locking mechanism locks the clamping head in the extended position axially and forms a fixed stop for the clamping head.

By means of the axially moveable clamping head, it is possible to insert or to remove a winding core in the winding apparatus without the winding core having to be moved in an axial direction as the clamping heads can be simply removed on both sides from the winding core or inserted into it. As a result, forces in the axial direction acting on the support of the winding apparatus are reduced as the winding core no longer has to be shifted axially.

By means of the locking mechanism, which forms a fixed stop for the clamping head, the clamping apparatus can be designed particularly compact as no aids are necessary, such as spring assemblies, in order to keep the clamping head in its extended position.

For example, a fixed stop is understood to mean locking in position without a permanently active application of a force, as would be the case, for example, by means of a spring or a permanently activated actuator.

The locking mechanism is located, for example, axially between the base and the clamping head, in particular the engagement section.

The base can be a bearing, for example a ball bearing.

In an embodiment, the locking mechanism is designed in such a way that it locks the clamping head in the extended position up to a maximum clamping force of at least 25 kN up to 30 kN, and/or it locks the clamping head in the lock position from moving axially from the extended position into the retracted position by means of positive locking, thereby providing reliable locking and a reliable fixed stop.

In one aspect, the locking mechanism is designed in such a way that its length in the axial direction is longer in the lock position than in the release position, in particular wherein a difference in length between the lock position and the release position equals the axial movement of the clamping head between the extended position and the retracted position. Through the length change in an axial direction, the locking mechanism can also be designed extremely compactly.

For a simple and compact locking mechanism, the locking mechanism can comprise a first locking element and a second locking element, wherein the first locking element and the second locking element are connected positively to each other in the lock position of the locking mechanism in the axial direction, in particular wherein the first locking element in the lock position rests on the second locking element in the axial direction.

For example, the first locking element abuts the base in the axial direction in the release position or rests on the base axially.

In an embodiment, the first locking element is a splined shaft and the second locking element is a splined hub, or vice versa, which engage with each other in the lock position, in particular wherein the splined shaft and the splined hub are aligned coaxially to each other and/or coaxially to the clamping head. By using a shaft-hub connection, an extremely durable connection and thus locking in position is achieved.

The splined hub is designed complementary to the splined shaft.

For example, teeth of the splined shaft or fillets of the splined hub are flattened in the axial direction towards the corresponding other locking element (in the lock position).

In an embodiment, the first locking element is fixed in the axial direction on the clamping head and/or connected non-rotatably to the clamping head, and/or the second locking element is supported in the axial direction on the base, thereby making it possible to lock the clamping head particularly securely in position.

For simple operation of the clamping head, the clamping apparatus can comprise a cylinder on which the clamping head is fixed, wherein the cylinder extends through the locking mechanism, in particular through the first locking element and the second locking element.

The cylinder is in particular coaxial to the first and second locking element and/or extends through the base.

In an embodiment, the clamping apparatus comprises a first actuator for actuating the locking mechanism, wherein the locking mechanism is adjustable between the lock position and the release position by means of the first actuator, in particular wherein the first actuator that is connected in such a way to the first locking element or the second locking element, that it can apply torque to the corresponding locking element. The locking mechanism can be locked in position automatically by means of the actuator.

To actuate the clamping head automatically, the clamping apparatus can comprise a second actuator which is connected to the clamping head, in particular by means of the cylinder, in such a way that it applies a force to the clamping head in the axial direction, in particular a force of more than 20 kN and/or up to 25 kN.

For example, the second actuator can move the clamping head between the extended position and the retracted position.

The second actuator can be a hydraulic or electric cylinder.

In an embodiment, the clamping head has a tapered engagement section. The tapered engagement section results in the winding core centres itself on the clamping head.

There is also provided a winding apparatus for winding and unwinding a flat material web, in particular a film. The winding apparatus has a support that comprises at least one receiving space for a winding core. Said at least one receiving space comprises a first clamping apparatus and a second clamping apparatus, wherein at least the first clamping apparatus is a clamping apparatus as previously described.

The features and advantages described for the clamping apparatus apply equally to the winding apparatus and vice versa.

The first and second clamping apparatus, in particular the corresponding clamping heads, are in particular coaxial to each other.

For example, the winding apparatus comprises at least one winding core that is held by the clamping apparatus rotatably in the receiving space.

The winding core has, for example, a length of 10 m, in particular at least 12 m, furthermore in particular at least 14 m, and/or a weight exceeding 20,000 kg, in particular exceeding 25,000 kg. Thus, particularly large or heavy winding cores can also be used. For example, a winding bale, thus a winding core with a material web wound on it, weighs from more than 30 t up to 34 t or more.

In an embodiment, the second clamping apparatus is a clamping apparatus with an axially adjustable clamping head, in particular a clamping apparatus as described previously.

For example, the support comprises two opposing rotatable wheels, wherein at least the clamping head and the locking mechanism of the first clamping apparatus is attached to a first one of the wheels and at least the clamping head of the second clamping apparatus is attached to a second one of the wheels.

If the second clamping apparatus is designed as previously described, the locking mechanism can also be located on the second wheel.

To provide a winding apparatus which can receive or deliver a material web continuously, the support comprises at least two of the receiving spaces, in particular wherein at least the clamping heads and the locking mechanisms of the first clamping apparatuses of the receiving spaces are attached to the first wheel and at least the clamping heads of the second clamping apparatuses of the receiving spaces are attached to the second wheel.

In an embodiment, the first clamping apparatus is arranged on an operator side of the winding apparatus, thereby ensuring an even simpler operation.

The base can be fixed immovably to the support, in particular to the corresponding wheel, and/or to a part of the support, in particular the corresponding wheel, thereby making the winding apparatus particular stable.

Moreover, there is provided a unit for producing a material web, in particular a film production unit, comprising a winding apparatus as described previously.

The features and advantages discussed for the clamping apparatus and/or the winding apparatus equally apply to the unit and vice versa.

Lists having a plurality of alternatives connected by “and/or”, for example “A, B and/or C” are to be understood to disclose an arbitrary combination of the alternatives, i.e. the lists are to be read as “A and/or B and/or C” or as “at least one of A, B or C”. The same holds true for listings with more than three items.

In, a unitfor producing a material web B is shown extremely schematically, which comprises several different units and apparatuses.

In the shown example, the unitis a film production unit, by means of which-without any limitation in the scope of the protection

In this case, the material web B is a plastics film. It is also conceivable that the material web B is a paper web, a textile web or a web made of another knitted fabric or material that can be stretched.

In the shown example, the unitcomprises an extrusion unit, a cast rolling unit, at least one stretching unit-such as a machine direction orienter(MDO), a transverse direction orienter(TDO)-, a draw roller unit and/or an edge treatment deviceas well as a winding apparatus.

The film produced is, for example, a biaxially stretched film, such as polypropylene (BOPP), polyethylene terephthalate (BOPET), polyamide film (BOPA), polyethylene film (BOPE), polylactic acid film (BOPLA), capacitor film (BOPP-C) or battery separator film (BSF).

To produce plastic films, a film is created on the chill roll of a cast rolling unitby means of an extrusion unit. To this end, the extrusion unitgenerates a melt from the starting products, such as granular material, said melt being applied to the chill roll, thereby creating the film.

This film is conveyed from the cast rolling unitto the machine direction orienteras a material web B. In the machine direction orienter, the film is stretched in the machine direction in order to obtain the film.