Patent Description:
Furthermore the invention relates to a method of changing a pallet support of a pile of sheets.

Preparing a pile of sheets for processing may require an in theory trivial task of turning the pile. However in practice such task may pose challenges. The pile may be distorted or in other ways be in disarray or misalignment.

Turning a pile of sheets may be required when the pile needs to be processed from the bottom end of the pile. One example is when the processing is printing on the backside or reverse-side of sheets in the pile.

Further challenges pose when the pile of sheets is on a pallet. Preparation for processing may also require a change of the pallet from one type of pallet to another type of pallet. The changing of a pallet may be from a disposable EUR-type of pallet to a process pallet.

<CIT> discloses a pile preparation unit of the type mentioned by way of introduction. This unit does not allow automatic handling and to extract existing process pallet and reuse it and apply on same pile of sheets after turning the pile <NUM> degrees.

<CIT> discloses a pile preparation unit according to the preamble of claim <NUM>. In particular, the document discloses a load handling apparatus for transferring a load from a first pallet to a second pallet by inserting a second pallet into an invertor followed by a <NUM> degrees rotation of the second pallet from a bottom position to a top position. A load bearing first pallet is then inserted into the invertor at lower position, and the invertor is rotated by a <NUM> degrees rotation to transfer the load from the first pallet to the second pallet, and the load bearing second pallet is retrieved from the invertor. Finally a third <NUM> degrees rotation of the first pallet from the top position to the bottom position is performed to retrieve the first pallet from the invertor.

Furthermore, <CIT> discloses a method of changing a pallet support of a pile of sheets with a first end and a second end where the pallet has a support side supporting the pile of sheets at the first end, the method comprises acts of:.

It is an object of the present invention to overcome one or more of the before mentioned limitations or challenges.

The invention is defined in the independent claims <NUM> and <NUM>.

An objective of the invention is achieved by a pile preparation unit for changing a pallet support of a pile of sheets with a first end and a second end where the pallet has a support side supporting the pile of sheets at the first end.

The pile preparation unit comprises a rotation unit configured with an infeed opening for receiving a pallet with a pile of sheets, the rotation unit configured with a rotating structure to rotate a lift unit about a rotational axis.

The lift unit is configured with a lift structure fixed to the rotating structure and has a lift plate movable along the lift structure to engage with the second end of the pile of sheets and to move and position the pile of sheets transverse, relative to the rotational axis, providing a portal for changing a pallet.

The rotating unit comprises a first conveyor configured to rotate with the rotating structure and the lift unit comprises a second conveyor configured as a second lift plate.

By a portal is understood a space or volume created where further actions or preparations can be performed. In particular this may involve actions or preparations where the pile of sheets being is to be prepared on a free end of the pile. Such actions may be a removal or extraction of a pallet, the insertion or delivery of a pallet, or both. Actions may also be a removal of sheets from the established free end of the pile.

The portal may be a space or volume inside the unit. The portal may also extend to include the exterior of the unit so that utilities may be transported in the portal or utilities may be applied in the portal. The portal may comprise different parts or sections where one part is for one action or one type of pallet and another part is for another action or another type of pallet.

The structure of the rotating unit allows automatic handling and to extract existing process pallet and reuse it and apply on same pile of sheets after turning the pile <NUM> degrees.

In an aspect related to changing the location of a pallet from one side of a pile of sheets to the opposite side of the pile of sheets, the following is disclosed. The changing of the location of a pallet may also involve the exchange of a first pallet with a second pallet. The first pallet may be a disposable pallet such as a EUR-pallet and the second pallet may be a process pallet. A process pallet may be a type of pallet that is used in a specific clean environment.

According to the invention, the lift unit comprises a first lift plate and a second lift plate, each configured to move and position in the lift structure to engage to the respective first end and second end of the pile of sheets.

Thereby providing a plate or face which position can be changed to support or carry a pile of sheets at the bottom and/or be removed from the top to generate the portal or space or volume required.

In an aspect the lift unit comprises a first conveyor and a second conveyor fixed to or configuring respective lift plates.

A conveyor will allow for a pallet to be transported into the unit, removed from the unit and to be positioned in the unit. There may be one conveyor. There may be two conveyors.

Advantageously, the conveyor has a flat form factor that will allow it to be rotated in the lift. Even more advantageously, two conveyors are arranged symmetrically allowing for receiving a pallet irrespective of which top or down position the unit has as a starting position. Whilst the conveyors may have the same or essentially the same form factor and be able to support or carry the weight of a same range of sizes and weight of objects, one conveyor may be for handing one type of objects and another conveyor for handling other types of objects.

According to the invention, the pile preparation unit is further configured with a pallet change module, comprising a pallet portal with movable pallet engagement means for engaging with a pallet for extraction from and insertion into a portal formed in an upper section of the rotation unit.

The pallet change module may be arranged for generating a portal for insertion or extraction from the end, such as the loading end or feeding end of the pile of sheets. The pallet change module may be arranged for generating a portal for insertion or extraction from the side of the unit.

In another aspect related to exchanging one pallet of one type with another pallet of another type, the following aspects are disclosed. The exchange may generally be of a first pallet with a second pallet. The first pallet may be a disposable type of pallet such as a EUR-pallet. The second pallet may be a so-called process pallet. Such process pallet may be configured or adapted to be operated or processed according to specific industrial settings.

In an aspect the pile preparation unit may be for exchanging a first pallet with a second pallet. The pallet change module may comprise a first pallet portal with movable first pallet engagement means arranged to extend to an extraction position in the rotation unit. The pallet change module may comprise a second pallet portal with movable second pallet engagement means, arranged to extend to a delivery position in the rotation unit the first and second pallet portal vertically separated.

The lift unit may be configured to move and position the lift plate for the pallet end of the pile of sheets to be positioned at the respective extraction position and delivery position.

The first and second pallet portals may be linear supports with guides for guiding pallet engagement means. The first pallet portal may be arranged for a linear movement of the first pallet engagement means and with a space outside the rotation unit for loading a pallet. The pallet engagement means may by the movement be inserted into the rotation unit in the portal volume to engage with a first pallet. The second pallet portal may be arranged similarly. The two pallet portals may be arranged above each other in the same support structure.

Having two pallet portals allows for parallel execution of actions, which allows for handling the first pallet in one fashion and the second pallets in another fashion. Furthermore having two pallet portals allows for faster actions in the rotation unit.

In an aspect the pallet change module is arranged on the side of the rotation unit and to extend the pallet engagement means, the first or second or both pallet engagement means into the rotation unit from a transverse direction to the rotational axis.

In an aspect the pile preparation unit may further comprise a pallet loading unit arranged on the opposite side of the pallet change module and fixed to the rotation unit. The pallet loading unit is configured to engage with and support a second pallet during rotation of the rotating unit and to release the second pallet on the second pallet engagement means.

The pallet loading unit may be configured with a pallet loading arm fixed to the rotating structure of the rotation unit and for engaging with a second pallet so that when the rotating unit rotates the pile of sheets the loading arm transports the second pallet, and turns it upside-down for delivery of the second pallet on the second pallet engagement means in the correct orientation for immediate insertion into the portal.

This arrangement greatly saves place and reduces the time of actions.

The pallet loading unit may be a unit for a PPU with a rotation unit. The pallet loading unit may be with a pallet loading arm connectable to the rotation unit and configured to engage with and support a pallet during a rotation of the rotating unit and configured to release the pallet when up-side down. The pallet loading unit may be configured to load a pallet from one side of the PPU and to rotate and turn the pallet up-side-down and deliver the pallet to a pallet change module with a pallet engagement means that is arranged on the opposite side of the PPU.

An objective of the invention may be achieved by a method of changing a pallet support of a pile of sheets with a first end and second end, where the pallet has a support side supporting the pile of sheets at the first end.

The method comprises an act of positioning the pallet supporting the pile of sheets on a first conveyor in a rotation unit.

The method further comprises an act of engaging a second conveyor with the second end of the pile of sheets.

The method further comprises an act of rotating the first and second conveyors upside down using the rotation unit.

The method further comprises an act of releasing the first conveyor from the first end of the pile of sheets;.

The method further comprises an act of extracting the pallet from the first end of the pile of sheets.

The method further comprises an act of engaging the first conveyor with the first end of the pile of sheets.

The method further comprises an act of rotating the first and second conveyors downside up using the rotation unit. The act of rotating may be with our without the pallet.

The method further comprises an act of releasing the second conveyor from the second end of the pile of sheets.

The method further comprises an act of inserting the same pallet or another pallet on the second end of the pile of sheets.

The method further comprises an act of engaging the second conveyor with the second end of the pile of sheets.

The method further comprises an act of rotating the first and second conveyors upside down using the rotation unit. This may be done with or without a pallet.

The method further comprises an act of ejecting the pallet supporting the pile of sheets from the second conveyor.

In an embodiment not according to the invention, there is disclosed a method of changing a pallet support of a pile of sheets with a first end and a second end, where the pallet has a support side supporting the pile of sheets at the first end. The changing may be an exchange of a first pallet with a second pallet.

The method may comprise one or more of the following acts.

There may be an act of positioning the pallet, supporting the pile of sheets on a first conveyor in a rotation unit.

There may be an act of engaging a lift plate arranged to move in a lift unit with the second end of the pile of sheets.

There may be an act of rotating the first pallet with the pile of sheets upside down using the rotation unit.

There may be an act of releasing the first conveyor from the first end of the pile of sheets by moving or lowering the lift plate, creating a portal for extraction and insertion of a pallet.

There may be an act of aligning the first pallet to an extraction position by moving the lift plate.

There may be an act of extracting the first pallet from the first end of the pile of sheets using the first pallet engagement means operated in the first pallet portal at the extraction position.

There may be an act of aligning the second end of the pile of sheets to an insertion position or delivery position. The act of aligning may be by moving the lift plate. There may be an act of inserting the second pallet to the second end of the pile of sheets, using the second pallet engagement means operated in the second pallet portal at the insertion position or delivery position.

There may be an act of engaging the second pallet with the first conveyor by moving the lift plate.

There may be an act of rotating the second pallet with the pile of sheets downside up using the rotation unit.

Furthermore the method may comprise one or more of following acts.

There may be an act of attaching a second pallet of the second type on the outside of the rotation unit.

There may be an act of rotating the attached second pallet in the same rotation movement.

There may be an act of releasing the second pallet to the second pallet portal.

The invention can advantageously be combined with one or more of the following five independent embodiments and the following five embodiments can be combined with each other.

A first independent embodiment may be a conveyor with a belt for transporting an object between a first end and a second end of the conveyor. The conveyor may have a first belt drive transmission at the first end and a second belt drive transmission at the second end. The drive transmission may be configured as freewheel-types in respective directions.

The conveyor may have an intermediate transmission system arranged between the first end and the second end and having a first communication with the first belt drive transmission and having a second communication with the second belt drive transmission.

The conveyor may have a drive system in communication with a drive shaft in the intermediate transmission system, and may be configured to turn the drive shaft bidirectional in a first drive direction and a second drive direction.

The conveyor may be configured with the drive shaft having an intermediate communication with the first communication through a first intermediate transmission and the second communication through a second intermediate transmission.

The disclosed conveyor is compact and low weight, which allows for installation with in industrial process equipment. The conveyer may be adapted to be rotated in a pile preparation unit. The conveyor is reversible, and has a single centre positioned drive system. The conveyor may transport heavy loads and with an equal load and equal torque in the forward and reverse directions. The conveyor eliminates or counteracts any "push" forces on the belt.

In an aspect, the first intermediate transmission is configured for engagement and force transmission at a first engagement position in the first drive direction and a second engagement position in the second drive direction and in-between having a first path of un-engagement.

In an aspect, the second intermediate transmission is configured for engagement and force transmission at a first engagement position in the first drive direction and a second engagement position in the second drive direction and in-between having a second path of un-engagement.

In an aspect, the intermediate communication is arranged so that for the first drive direction, the first intermediate transmission is enabled for engagement at the first engagement position whilst the second intermediate transmission is in the second path of un-engagement. For the same aspect and for the second drive direction, the second intermediate transmission is enabled for engagement at the second engagement position whilst the first intermediate transmission is in the first path of un-engagement.

Thereby is achieved that the conveyor for the first drive direction, engages the first belt drive transmission for a first pull of the belt towards the first end whilst freewheeling the second belt drive transmission. For the second drive direction it is achieved that the second belt drive transmission engages for a second pull of the belt towards the second end whilst free-wheeling the first belt drive transmission.

Such conveyor will pull towards the respective first and second end whilst releasing tension in respective opposite ends. By pull is understood that traction power or a traction force is applied from the respective first or second end of the conveyor. This will allow the conveyor to transport heavy objects back and forth without building-up tension. A further advantage is that tensions are released during use situations of "asymmetric load" where a heavy object is transported in one direction, substantially of-floaded and then reversed as a light object. A further advantage is that the configuration results in a flat structure of the conveyor in a direction transverse to the face of the belt for engaging with the object.

In an aspect the intermediate communication comprises an intermediate chain engaging with a drive cogwheel on the driveshaft, a first intermediate drive cogwheel on the first intermediate transmission and a second intermediate drive cogwheel on the second intermediate transmission. In an aspect the first and second communications comprise respective first and second communication chains engaging respective first and second belt cogwheels in the respective first and second belt drive transmissions with respective first and second communication cogwheels in the respective first and second intermediate transmissions. In an aspect the respective first and second intermediate transmissions each has a respective first and second intermediate drive cogwheel and a respective first and second communication cogwheel sharing respective common first and second intermediate shafts. Furthermore, the respective first and second intermediate transmission may be configured with engagement means to transmit force at least from the respective first and second drive intermediate cogwheels to the respective first and second communication cogwheels.

Herby is achieve that the intermediate transmission can apply a pull or traction force to the respective first and second ends of the conveyor. The engagement or appliance of a force then depends on the direction of rotation so that a pull or traction force is from one end of a conveyor for one direction of rotation of the drive and that a pull or traction force is from the other end of the conveyor for an opposite direction of rotation of the drive.

A second independent embodiment may be a pile preparation unit (PPU) for preparing a pile of sheets. The pile of sheets has a first end, which first end is optionally standing on a pallet, and opposite a free second end, a front edge side and a side edge side.

The PPU comprises a rotation base configured for standing on a floor and for supporting a rotation unit, configured with an infeed side for receiving a pile of sheets in a feed direction. The pile of sheets may optionally be on a pallet. The rotation unit may have a rotation unit frame with a rotation unit frame cross section. The rotation unit may be configured with an edge side support unit, configured with an edge side support face to support an edge side of the pile of sheets when the pile of sheets is in a rotated position to lean on the edge side support face. The rotation unit may have a lift unit configured to engage a lift plate to the free second end of the pile of sheets in the pile preparation position and to lift a pile of sheets.

In an aspect of the pile preparation unit (PPU), the rotation unit frame comprises two guides shifted in the feed direction relative to each other and each fixed to the rotation base and guiding a belt driven by a rotation unit drive system in the rotation base. The belt may be a timing belt. The belt may be a chain.

For clarity and understanding, the pile of sheets is an object to which the pile preparation unit is directed to. A person skilled in the art will thus appreciate modifications of the PPU according to variations in a size or shape of a pile of sheets.

Thus the PPU provides an effective and automated apparatus for preparing a pile of sheets for processing. The disclosed PPU may handle piles of sheets of a multiplicity of types of pile-shapes and -sizes as well as a multiplicity of sheet types and weights. The disclosed PPU saves time, the PPU allows for a quick setup for a new material in a pile of sheets. Piles prepared by the PPU will be more identical and PPU will provide a substantially constant throughput. The PPU may be fully integrated in an ERP system. The rotation unit may rotate about a rotational axis, which axis may the feed direction. The rotation unit may be configured to rotate a conveyor about the feed direction. The conveyor may be configured to transport a pallet with a pile of sheets from the infeed side in the feed direction to a pile preparation position. In an aspect the belts encircle the conveyor.

A third independent embodiment may be related to changing the location of a pallet from one side of a pile of sheets to the opposite side of the pile of sheets, the following aspects of the invention is disclosed. The changing of the location of a pallet may also involve the exchange of a first pallet with a second pallet. The first pallet may be a disposable pallet such as a EUR-pallet and the second pallet may be a process pallet. A process pallet may be a type of pallet that is used in a specific clean environment.

In an aspect the rotating unit comprises a first conveyor configured to rotate with the rotating structure and the lift unit comprises a second conveyor configured as a second lift plate. This allows automatic handling and to extract existing process pallet and reuse it and apply on same pile of sheets after turning the pile <NUM> degrees.

In an aspect the lift unit comprises a first lift plate and a second lift plate, each configured to move and position in the lift structure to engage to the respective first end and second end of the pile of sheets.

A fourth independent embodiment may be a pile preparation unit for changing a first pallet with a second pallet, the pallets for supporting a pile of sheets with a first end and second end where the pallet has a support side, supporting the pile of sheets at the first end and an opposite base side.

The pile preparation unit may comprise a rotation unit configured with an infeed opening for receiving a pallet with a pile of sheets. The rotation unit is configured with a rotating structure to rotate a lift unit about a rotational axis.

The lift unit may be configured with a lift structure fixed to the rotating structure and has a lift plate movable along the lift structure to engage with the second end of the pile of sheets and to move and position the pile of sheets transverse, relative to the rotational axis, providing a portal for changing a pallet.

The pallet preparation unit may comprise a pallet change module comprising a pallet portal with movable pallet engagement means for engaging with a pallet, for extraction from and/or insertion into the portal formed in an upper section of the rotation unit, when the lift plate is in the lower section of the rotation unit.

The pallet preparation unit may thus receive a pile of sheets and exchange one pallet with another pallet in an automated fashion. The rotation unit may comprise a unit frame with a rotation unit frame cross section. The rotation unit may be configured to rotate a conveyer about the feed direction. The conveyer may be configured to transport a pallet with a pile of sheets from the infeed side in the feed direction to a pile preparation position.

In an aspect the pallet change module comprises a first pallet portal with movable first pallet engagement means arranged to extend to an extraction position in the rotation unit.

The pallet change module may comprise a second pallet portal with movable second pallet engagement means arranged to extend to a delivery position in the rotation unit, where the first and second pallet portals are vertically separated.

The lift may be configured to move and position the lift plate for the pallet end of the pile of sheets to be positioned at the respective extraction position and delivery position.

In an aspect the pallet change module is arranged on the side of the rotation unit and to extend the pallet engagement means, the first or second or both pallet engagement means into the rotation unit from a transverse direction to the rotational axis. The direction of insertion may be essentially horizontal and the pallet change module may be arranged on the side of the rotation unit relative to the infeed on a front. The pallet change module may comprise guides and supports as required to achieve a horizontal movement of a pallet. Likewise the engagement means are complementary in shape to the pallets. The engagement means may be adjustable to enable a fit to pallets of different types. A person skilled in the art will appreciate a need to perform adjustments and balance or dimension the construction as required for a pallet of a specific type to be moved in the pallet portal. Counterweights may be required. Similarly actuators may be required to adjust the position and the placement of the engagement means and thus the positioning of the pallet. The drive system may be a belt drive type of system that drives the movement. In one embodiment the first and second pallet engagement means may be identical.

In an aspect the pile preparation unit may further comprise a pallet loading unit arranged on the opposite side of the pallet change module and with a pallet loading arm fixed to the rotation unit. The pallet loading arm is configured to engage with and support a second pallet during rotation of the rotating unit and to release the second pallet on the second pallet engagement means. The pallet loading unit is configured to engage with and support a second pallet during rotation of the rotating unit and to release the second pallet on the second pallet engagement means. The pallet loading unit may be configured with a pallet loading arm fixed to the rotating structure of the rotation unit and for engaging with a second pallet so that when the rotating unit rotates the pile of sheets the loading arm transports the second pallet, and turns it upside-down for delivery of the second pallet on the second pallet engagement means in the correct orientation for immediate insertion into the portal.

A fifth independent embodiment may be a pile sheet remover system (PSR) for preparing a pile of sheets with a height, a free end, and a side of sheet edges for processing in a pile preparation unit (PPU).

The PSR may comprise a sheet removing unit having a support frame supporting a moving frame, configured for a linear movement in an attack direction towards the side and the free end of the pile of sheets.

The moving frame may have a side support plate with a side support face arranged to face and apply to the side of the pile of sheets.

The PSR may have a grab plate arranged with a grab face essentially perpendicular to the side support face and extending beyond the side support face in the attack direction, configured with a grab actuator for a grab movement towards the free end of the pile of sheets.

The PSR may have one or more attack knives arranged below the grab plate to face the side of the pile of sheets, and configured with one or more attack actuators for a first attack movement in the attack direction for insertion of the one or more attack knives between a pair of sheets, i.e. between two adjacent sheets.

It is thereby achieved that top sheets can be removed automatically. Furthermore the arrangement can be adjusted according to different characteristics of a pile of sheets. A further advantage is that the system can be arranged in a pile preparation unit, which in other aspects such are turning the pile, airing the pile or changing of a pallet or the location of the pallet.

In an aspect there is a first attack knife for a first attack movement and a second attack knife for a second attack movement. The first attack knife may be a smaller knife with a blade in the attack direction. The first knife may be a razor blade type of knife. The second attack knife may be larger than the first knife and with a sharp and point type of form in the attack direction. The knife may also be a stylus type of shape.

In an aspect one or more second attack knives are configured with one or more transverse actuators for a movement transverse to the line of attack direction and parallel to the sheet edges. The knives used for the transverse movement may be second attack knives. There may be one knife for a transverse movement from a center area to a periphery. There may be another knife for a transverse movement from the center area to a periphery on the other side. There may be two second attack knives, each being configured with individual transverse actuators.

This effectively separates sheets to be removed from the remaining sheets. A further advantage is that the transverse movement leaves the knives in a favorable position when the actual removal takes place and thus decreases the risk of destroying the sheets.

In an aspect one or more first attack knives are configured with one or more edge lift actuators for a lift movement transverse to the line-of-attack direction and perpendicular to the sheet edges. The lift movement lifts the edge of the sheets upwardly and thus makes it possible for a further insertion into the sheets. Advantageously the movement is performed swiftly to increase the separation of sheets. The lift actuators may be pneumatic actuators. The actuators may be adjustable in action length or speed.

In an aspect one or more attack knives are configured for a second attack movement extending the first attack movement in the attack direction for further insertion of the one or more attack knives between the pair of sheets. This second movement may be provided by the same actuator used for the first movement. The second movement may also be provided by additional actuators. Thus there may be a first set of actuators and a second set of actuators.

Embodiments of the invention will be described in the figures, whereon:.

<FIG> discloses a pile preparation unit <NUM> for changing a pallet <NUM> support of a pile of sheets <NUM>. The pile of sheets having a first end <NUM> and second end <NUM> and the pallet <NUM> has a support side <NUM> supporting the pile of sheets <NUM> at the first end <NUM>.

The pile of sheets <NUM> and the pallets <NUM> is feed in a feed direction <NUM>. The pallets <NUM> are removed in the feed direction <NUM>.

The pile preparation unit <NUM> has a rotation unit <NUM> configured with two infeed openings <NUM> for receiving a pallet <NUM> with a pile of sheets <NUM>. The rotation unit <NUM> is configured with a rotating structure <NUM> to rotate a lift unit <NUM> about a rotational axis <NUM>.

The lift unit <NUM> is configured with a lift structure <NUM> fixed to the rotating structure <NUM> and having a lift plate <NUM> movable along the lift structure <NUM> to engage with the second end <NUM> of the pile of sheets <NUM> and to move and position the pile of sheets <NUM> transverse relatively to the rotational axis <NUM> providing a portal <NUM> for changing a pallet <NUM>. This portal <NUM> is also referred to as a pallet portal <NUM>.

The rotation unit <NUM> comprises a first conveyor <NUM> configured to rotate with the rotation structure <NUM>. The first conveyor <NUM> may act as a first lift plate <NUM>, which in this embodiment rotates with the rotation unit <NUM>. The lift unit <NUM> comprises a second conveyor <NUM> configured as a second lift plate <NUM>. In this embodiment the second lift plate <NUM> may move in the lift unit <NUM> and thus rotate when the lift unit is rotated by the rotation unit <NUM>.

A portal <NUM> or pallet portal <NUM> is created when there is an open space between the first end <NUM> of the pile of sheets <NUM> and the first lift plate <NUM> or when there is an open space between the second end <NUM> of the pile of sheets <NUM> and the second lift plate <NUM>.

In one embodiment one or both of the first and second lift plates <NUM>, <NUM> is a conveyor <NUM>.

In one embodiment the first lift plate <NUM> is a first conveyor <NUM> that rotates with the rotation unit <NUM>.

In another embodiment the first plate <NUM> is a first conveyer <NUM> that is in the lift unit <NUM> and thus rotates with the lift unit <NUM>.

<FIG> illustrate the extraction <NUM> of a pallet <NUM>. The extraction <NUM> is done in seven steps.

In <FIG> discloses a pile preparation unit <NUM> for changing a pallet <NUM> support of a pile of sheets <NUM>. The pile of sheets <NUM> has been feed into the pile preparation unit <NUM>.

In <FIG> the second lift plate <NUM> clamps down onto the second end <NUM> of the pile of sheets.

In <FIG> the rotation unit <NUM> rotates the pile of sheets <NUM> around a rotational axis <NUM>. Hence the pile of sheets <NUM> is upside/down compared to preceding figures.

In <FIG> pallet engagement means <NUM> is inserted in the feed direction <NUM> for engagement with the pallet <NUM>.

In <FIG> the pallet engagement means <NUM> has been inserted into the pile preparation unit <NUM> and the pallet engagement means <NUM> has engaged with the pallet <NUM>.

<FIG> discloses the extraction of the pallet <NUM>.

In a step between <FIG> and <FIG> the first lift unit <NUM> clams down onto the first end <NUM> of the pile of sheets <NUM>.

In <FIG> the rotation unit <NUM> has rotated the pile of sheets <NUM> around a rotational axis <NUM>. Hence the pile of sheets <NUM> is in the same position as in <FIG>, but without a pallet <NUM>.

<FIG> illustrate the insertion <NUM> of a pallet <NUM>.

In <FIG> a pallet <NUM> is inserted into the pile preparation unit <NUM> by a pallet change module <NUM> using pallet engagement means <NUM>.

In <FIG> the pallet engagement means <NUM> moves the pallet <NUM> down onto the second end <NUM> of the pile of sheets <NUM>.

In <FIG> the pallet engagement means <NUM> extracts leaving the pallet <NUM> on the second end <NUM> of the pile of sheets.

In <FIG> the extraction of the pallet engagement means <NUM> is completed.

In <FIG> the second lift plate <NUM> is moved downwards onto the backside of the pallet <NUM>.

In <FIG> the rotation unit <NUM> rotates the pile of sheets <NUM> around a rotational axis <NUM>. Hence the pile of sheets <NUM> is upside/down compared to <FIG>.

In <FIG> second lift plate <NUM> is moved downwards, so the pile of sheets <NUM> can be removed.

In one embodiment the removal of the pile of sheets is done by a conveyor <NUM>.

In another embodiment the removal of the pile of sheets is done by a forklift.

In <FIG> the pile of sheets <NUM> is flipped so that the second end <NUM> of the pile of sheets <NUM> is supported by the support side <NUM> of the pallet <NUM>.

In another embodiment one or both lift plates <NUM> are conveyors <NUM>.

In another embodiment none of the lift plates <NUM> are conveyors <NUM>.

In another embodiment the pallet <NUM> is removed without adding a new pallet <NUM>.

In another embodiment only one pallet <NUM> is used.

In another embodiment the pile of sheets <NUM> has no pallet <NUM> before insertion into the pile preparation unit <NUM> and a pallet <NUM> is added to either the first end <NUM> and second end <NUM> or both.

In another embodiment the pile of sheets <NUM> has no pallet <NUM> and the pile of sheets <NUM> is flipped.

In another embodiment a pallet <NUM> is placed on both the first end <NUM> and the second end <NUM> of the pile of sheets <NUM>.

<FIG> illustrate a pile preparation unit with another embodiment of a pallet change module.

The pile preparation unit <NUM> has a pallet change module <NUM>. The pallet change module <NUM> has a first pallet portal <NUM> with movable first pallet engagement means <NUM> arranged to extend to an extraction position <NUM> in the rotation unit <NUM> and a second pallet portal <NUM> with movable second pallet engagement means <NUM> arranged to extend to a delivery position <NUM> in the rotation unit <NUM> the first and second pallet portal <NUM>, <NUM> vertically separated.

The extraction position <NUM> and delivery position <NUM> is not shown in <FIG>.

The pile preparation unit <NUM> has a lift unit <NUM>. The lift unit <NUM> is configured to move and position the lift plate <NUM> for the second end <NUM> of the pile of sheets <NUM> to be positioned at the respective extraction position <NUM> and delivery position <NUM>.

The pallets <NUM> are feed in the feed direction <NUM>.

<FIG> discloses the pallet loading unit <NUM> with pallet loading arms <NUM>.

<FIG> illustrate extraction and insertion of a pallet.

<FIG> discloses a top view of the pile preparation unit <NUM> also shown in <FIG>.

In <FIG> the pile of sheets <NUM> have been rotated by the rotation unit <NUM> around a rotational axis <NUM>. During the rotation the pallet loading unit <NUM> delivers a second pallet <NUM> for the second pallet engagement means <NUM>.

In <FIG> the lift unit <NUM> moves the pile of sheets <NUM> a bit downwards by lowering of the second lift plate <NUM>. The first pallet <NUM> is placed in the first pallet portal <NUM> and the first pallet <NUM> is therefore at the extraction position <NUM>.

The second pallet <NUM> is placed at the second pallet engagement means <NUM>, which is vertically at the same height as the second pallet portal <NUM>; thus the second pallet is at the delivery position <NUM>.

In <FIG> the second engagement means <NUM> moves the second pallet <NUM> into the second pallet portal <NUM> to deliver the second pallet <NUM>.

In <FIG> the first pallet <NUM> has been removed by the first pallet engagement means <NUM>.

The rotation unit <NUM> may then rotate the pile of sheets <NUM> around a rotational axis <NUM>. The pile of sheets <NUM> would then be in the initial position shown in <FIG>, but with a different pallet <NUM>.

The pile of sheets <NUM> can then be removed from the pile preparation unit <NUM>.

In another embodiment the removal of the pile of sheets is done by a truck.

In <FIG> the pallet <NUM> of the pile of sheets <NUM> is changed from a first pallet <NUM> to a second pallet <NUM>.

In another embodiment the pallet <NUM> is changed while flipping the pile of sheets <NUM>.

In another embodiment the pile of sheets <NUM> has no pallet <NUM> before insertion into the pile preparation unit <NUM> is added to either the first end <NUM> and second end <NUM> or both.

<FIG> illustrate a different angle of the pallet change module.

<FIG> illustrates a pallet. The pallet is a process pallet having a face with linear recesses. The pallet engagement means may be spears or rods complementary arranged to engage with the recesses in the pallet.

<FIG> illustrates a method <NUM> of changing a pallet <NUM> support of a pile of sheets <NUM> with a first end <NUM> and a second end <NUM> where the pallet <NUM> has a support side <NUM> supporting the pile of sheets <NUM> at the first end <NUM>. The method comprises of a series of acts.

There may be an act of positioning <NUM> the pallet <NUM> supporting the pile of sheets <NUM> on a first conveyor <NUM> in a rotation unit <NUM>.

There may be an act of engaging <NUM> a second conveyor <NUM> with the second end <NUM> of the pile of sheets <NUM>.

There may be an act of rotating <NUM> the first and second conveyors <NUM>, <NUM> upside down using the rotation unit <NUM>.

There may be an act of releasing <NUM> the first conveyor <NUM> from the first end <NUM> of the pile of sheets <NUM>.

There may be an act of extracting <NUM> the pallet <NUM> from the first end <NUM> of the pile of sheets <NUM>.

There may be an act of engaging <NUM> the first conveyor <NUM> with the first end <NUM> of the pile of sheets <NUM>.

There may be an act of rotating <NUM> the first and second conveyors <NUM>, <NUM> downside-up using the rotation unit <NUM>. This act may be without the pallet <NUM>.

There may be an act of releasing <NUM> the second conveyor <NUM> from the second end <NUM> of the pile of sheets <NUM>.

There may be an act of inserting <NUM> the same pallet <NUM> or another pallet <NUM> on the second end <NUM> of the pile of sheets <NUM>.

There may be an act of engaging <NUM> the second conveyor <NUM> with the second end <NUM> of the pile of sheets <NUM>.

There may be an act of rotating <NUM> the first and second conveyors <NUM>, <NUM> upside down using the rotation unit <NUM>. This act may be with the pallet <NUM>.

There may be an act of ejecting <NUM> the pallet <NUM> supporting the pile of sheets <NUM> from the second conveyor <NUM>.

<FIG> illustrates a method <NUM> of changing a pallet <NUM> support of a pile of sheets <NUM> with a first end <NUM> and second end <NUM> where the pallet <NUM> has a support side <NUM> supporting the pile of sheets <NUM> at the first end <NUM>, where the changing is from a first pallet <NUM> to a second pallet <NUM>. The method comprises of a series of acts.

There may be an act of positioning <NUM> the pallet <NUM>, supporting the pile of sheets <NUM> on a first conveyor <NUM> in a rotation unit <NUM>.

There may be an act of engaging <NUM> a lift plate <NUM> is arranged to move in a lift unit <NUM> with the second end <NUM> of the pile of sheets <NUM>.

There may be an act of rotating <NUM> the first pallet <NUM> with the pile of sheets <NUM> upside down using the rotation unit <NUM>.

There may be an act of releasing <NUM> the first conveyor <NUM> from the first end <NUM> of the pile of sheets <NUM> by moving or lowering the lift plate <NUM>, creating a portal <NUM> for extraction and insertion of a pallet <NUM> and.

There may be an act of aligning <NUM> the first pallet <NUM> to an extraction position 660by moving the lift plate <NUM>.

There may be an act of extracting <NUM> the first pallet <NUM> from the first end <NUM> of the pile of sheets <NUM> using the first pallet engagement means <NUM> operated in the first pallet portal 641at the extraction position <NUM>.

There may be an act of aligning <NUM> the second end <NUM> of the pile of sheets <NUM> to an insertion position <NUM> or delivery position by moving the lift plate <NUM>.

There may be an act of inserting <NUM> the second pallet <NUM> to the second end 132of the pile of sheets <NUM> using the second pallet engagement means <NUM> operated in the second pallet portal <NUM> at the insertion position <NUM> or delivery position.

There may be an act of engaging <NUM> the second pallet <NUM> with the first conveyor <NUM> by moving the lift plate <NUM>.

There may be an act of rotating <NUM> the second pallet <NUM> with the pile of sheets <NUM> downside up using the rotation unit <NUM>.

There may be further acts for loading a pallet from a pallet storage and onto or into the pallet change module.

The act of loading may comprise one or more of the following acts.

There may be an act of attaching <NUM> a second pallet <NUM> of the second type <NUM> on the outside of the rotation unit <NUM>.

There may be an act of rotating <NUM> the attached second pallet <NUM> in the same rotation movement.

There may be an act of releasing <NUM> the second pallet <NUM> to the second pallet portal <NUM>.

Claim 1:
A pile preparation unit (<NUM>) for changing a pallet (<NUM>) support of a pile of sheets (<NUM>) with a first end (<NUM>) and second end (<NUM>) where the pallet (<NUM>) has a support side (<NUM>) supporting the pile of sheets (<NUM>) at the first end (<NUM>), the pile preparation unit (<NUM>) comprising:
- a rotation unit (<NUM>) configured with an infeed opening (<NUM>) for receiving a pallet (<NUM>) with a pile of sheets (<NUM>), the rotation unit (<NUM>) configured with a rotating structure (<NUM>) to rotate a lift unit (<NUM>) about a rotational axis (<NUM>);
wherein the lift unit (<NUM>) comprises a first lift plate (<NUM>) and a second lift plate (<NUM>), each configured to move and position in a lift structure (<NUM>) to engage to the respective first end (<NUM>) and second end (<NUM>) of the pile of sheets (<NUM>);
wherein the lift unit (<NUM>) is configured with a lift structure (<NUM>) fixed to the rotating structure (<NUM>) and has a lift plate (<NUM>) movable along the lift structure (<NUM>) to engage with the second end (<NUM>) of the pile of sheets (<NUM>) and to move and position the pile of sheets (<NUM>) transverse, relative to the rotational axis (<NUM>) providing a portal (<NUM>) for changing a pallet (<NUM>), wherein the rotating unit comprises a first conveyor (<NUM>) configured to rotate with the rotating structure (<NUM>) and the lift unit (<NUM>) comprises a second conveyor (<NUM>) configured as a second lift plate (<NUM>), characterised in that the pile preparation unit (<NUM>) is configured with a pallet change module (<NUM>) comprising a pallet portal (<NUM>) with movable pallet engagement means (<NUM>) for engaging with a pallet (<NUM>) for extraction (<NUM>) from and insertion (<NUM>) into a portal (<NUM>) formed in an upper section of the rotation unit (<NUM>).