GB2501673A

GB2501673A - Laser System

Info

Publication number: GB2501673A
Application number: GB1205172.8A
Authority: GB
Inventors: Douglas Stewart; Berty De Jong; Michael Fairhurst
Original assignee: DEART INTERNAT Ltd
Current assignee: DEART INTERNAT Ltd
Priority date: 2012-03-23
Filing date: 2012-03-23
Publication date: 2013-11-06
Also published as: GB2501673A8; GB201205172D0; WO2013140166A1

Abstract

A laser cutting system for trimming an item of manufacture such as a can 301 , comprises a rotatable support 213 with multiple stations 111 to receive multiple items to be trimmed, a laser scanning device to scan a laser trimming beam through multiple positions corresponding to exit stations for the device, the support to provide an item to be trimmed at an exit station and to rotate the item in its station in contact with the trimming beam to cut a portion of the item, wherein the trimming beam is derived from a source laser beam parallel to a first axis, the trimming beam parallel to a second axis which is different to the first.

Description

LASER SYSTEM

BACKGROUND

Metal containers for food and beverages are normally manufactured by drawing and wall ironing (DWI, also referred to as drawing and ironing (D&l)) or drawing and re-drawing (DRD) processes. Such containers typically comprise a cup-like can body and a closure that is subsequently fastened to the open end of the can body to form the container.

In a conventional DWI (D&l) process for example, a blank which has been stamped out from a metal sheet is drawn though a drawing die under the action of a punch to form a cup. The cup can then be pushed through multiple annular dies in order to reduce the thickness of the sidewall of the cup. This results in elongation in the sidewall of the cup.

Typically, the open end of the cup must be trimmed after it has been elongated since the edge will normally be uneven as a result of the manufacturing process. An irregular surface of uneven height around the circumference of the open end of a cup body can create problems in further processing. For example, the cup may be rejected, or, if filled and sealed with a lid, the seal may be defective thereby leading to failure.

The irregular end of the cup is trimmed using a rotary trimmer. For example, after exiting a body maker, can bodies can be fed to a trimmer by being loaded into an infeed chute that places the can bodies into a star wheel. As the cans rotate around the star wheel, they reach the trimmer cartridge one at a time. A rotary can trimmer typically comprises a pair of parallel rotating blades that open and close to allow a can body to be placed in position for trimming and to be removed after trimming is complete. Once a can body reaches the trimmer cartridge, it is held in position so that one blade of the trimmer is inside the can body and the other blade is outside. With the blades closed the can body is then rotated to cause the blades to trim the entire circumference of the can resulting in a regular surface around the circumference of the can.

SUMMARY

According to an example, there is provided a laser cutting system for trimming an item of manufacture, comprising a rotatable support with multiple stations to receive multiple items to be trimmed, a laser scanning device to scan a laser trimming beam through multiple positions corresponding to exit stations for the device, the support to provide an item to be trimmed at an exit station and to rotate the item in its station in contact with the trimming beam to cut a portion of the item, wherein the trimming beam is derived from a source laser beam parallel to a first axis, the trimming beam parallel to a second axis which is different to the first.

The support can rotate around the first axis while rotating an item to be trimmed around a third axis. The laser scanning device includes a laser source to provide the source beam for the system along the first axis, and a system to alter the direction of the laser source to form the trimming beam along the second axis. The system to alter the direction of the laser source can be independently rotatable around the first axis. The system to alter the direction of the laser source can be an angled mirror. The support can provide multiple items to be trimmed in rotatable succession at exit stations of the device. The laser scanning device can track an item to be trimmed at an exit station. The laser scanning device can track the item to be trimmed by rotating in unison with the support.

According to an example, there is provided a laser scanning device suitable for use with a system as described herein. The system can alter the direction of the laser source using a prism or conical shaped mirror.

According to an example, there is provided a laser cutting method in which a cutting laser beam is applied to an item to be cut at a cutting point, comprising providing a source laser beam along a first axis, scanning the source laser beam through multiple positions corresponding to exit stations using a scanning device to provide a cutting beam along a second axis, providing an item to be cut at an exit station, and tracking the item using the cutting beam by rotating the exit station in unison with the item. Scanning the source laser beam can include reflecting the source laser beam from a rotatably mounted reflective surface. The rotatably mounted reflective surface can be a mirror mounted on a rotation device. An item to be cut can be supported on a rotating mount including multiple stations for receiving multiple items to be cut. The rotating mount can rotate around the first axis. The axis of the cutting beam can be orthogonal to the first axis. The cutting point can be altered as the item to be cut is tracked by the cuffing beam.

According to an example, there is provided a computer program embedded on a non-transitory tangible computer readable storage medium, the computer program including machine readable instructions that, when executed by a processor, implement a method for controlling a laser trimming device, the method comprising controlling power for a source laser beam, scanning the source laser beam through multiple positions corresponding to exit stations to provide a cutting beam using a motor, controlling the position of an item to be trimmed at an exit station, rotating the exit station, and tracking the item in the exit station using the cuffing beam using a controller.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which: Figure 1 is a schematic block diagram of a process of manufacture according to an example; Figure 2 is a schematic block diagram of a laser cutting system according

to an example;

Figure 3 is a schematic block diagram of a laser trimming system according

to an example;

Figure 4 is a schematic diagram of a mode of operation of a laser cutting system according to an example; Figure 5 is a schematic diagram of a laser trimming system according to an

example;

Figure 6 which is a schematic diagram of a laser scanning device according

to an example; and

Figure 7 is a schematic block diagram of a system according to an

example.

DETAILED DESCRIPTION

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Although examples will be described herein with reference to the trimming and/or cutting of one or more specific items of manufacture, a system and method as described are not to be construed as so limited. For example, a laser cutting system and method as described herein is equally suited for use with any article of manufacture in which it is desired to quickly perform accurate and repeatable cuts or trims. Accordingly, a support structure as described herein for example can be modified to accommodate items which are to be cut, scored or trimmed.

Figure 1 is a schematic block diagram of a process of manufacture according to an example. The process can be used to produce an item of manufacture such as a can for example, which can be suitable for holding food or beverages, or any other article such as a container for storing non-edible substances or any other article which it is desirable to trim or cut.

Accordingly, certain steps described below, particularly with respect to initial fabrication or manufacture, can be modified, augmented or dispensed with depending on the article in question, and it will be entirely apparent to the skilled person which of those steps may be so affected and how.

Further steps in the process can be provided, either upstream, downstream or a combination of the two relative to the steps outlined below. In block 101 a blank is provided, which blank can be used to form a cup, container or can for example (all of which terms are used interchangeably herein).

Typically, the blank is pressed through a draw ring using a ram to form the cup. In an example, a blank can be formed from tin plated steel or aluminium.

In block 103 the cup formed in block 101 is reduced in diameter using a wall-ironing machine in which the wall thickness of the can is reduced by "ironing". That is, the cup is rammed through multiple wall-ironing rings of differing (typically reducing) diameter with a consequent lengthening of the can and thinning of the can wall.

In block 105, the lengthened can is trimmed. Trimming can be performed to remove any irregularities in the circumference of the open end of the can for example, and/or to reduce the length of the can. According to an example, trimming is effected using a laser cutting system 107 in which multiple items can be trimmed in succession. Throughput is increased by virtue of the fact that multiple items to be trimmed can be arranged in a rotatable support structure 109 with multiple item support stations 111 which can be tracked by a trimming laser beam such that trimming of a portion of an item on the support can be commenced immediately following the trimming of another item and whilst the another item is still present in the support structure before ejection for processing in a subsequent process station for example. In an alternative example, an item which has been trimmed can be ejected from the support immediately afterwards, and need not remain in the support when a subsequent trimming action for another item begins. As explained above, a support structure can be used to accommodate any article for trimming, cutting or scoring.

The laser cutting system includes a laser scanning device 113 which is used to scan a laser trimming beam through multiple positions corresponding to exit stations for the beam. In an example, the scanning device provides a source laser beam along a first axis which is scanned to provide a trimming beam along multiple axes which are transverse or orthogonal to the first axis, or which subtend one or more predefined angles to the first axis. For example, the angle subtended at each exit station can be different or can be varied continuously as the trimming beam is scanned thereby enabling all manner of cuts and so on to be made.

Once trimmed, an article can be further processed in subsequent stations which can include cleaning, printing, filling and drying for example.

In an example, an exit station for the beam corresponds to a start position for a trimming operation. Indexing through exit stations allows multiple items to be trimmed as they are conveyed as will be described below.

Typically, indexing to an exit station to start a trim operation means that the trimming beam is set to impinge on an item to be trimmed, which item is tracked by the beam until trimming is completed. The beam can then be indexed to another exit station, which can correspond to the same start position, so that another item can be trimmed.

In an example, the support structure 109 can be in the form of a starwheel or other rotary support device with support stations 111 at the periphery.

The support stations 111 are used to receive an item to be trimmed. In an x example, the structure 109 rotates so as to convey an item to be trimmed from an input to an output. An item to be trimmed can be independently rotated within a support station 111 as it is being conveyed. Accordingly, the structure 109 rotates to convey an item from an input of the structure to an output, whilst items being conveyed are simultaneously rotated in their respective support stations 111 and trimmed.

Figure 2 is a schematic block diagram of a laser cutting system according to an example. A laser source is provided in block 201. The source can be any laser device which is capable of providing a source beam which has sufficient power to cut, score or otherwise trim an item for manufacture. In an example, an item of manufacture is a can which has a nominal thickness in the range 100 to 500 micrometers.

Source beam 203 from laser source 201 travels along or parallel to a first axis 205, and impinges on a system 206 to alter the direction of the beam 203 to form a trimming beam 207 which travels parallel to a second axis 209. In an example, the second axis 209 is orthogonal to the first axis 205.

In an alternative example, the second axis 209 subtends an angle in the range 45-1 35 degrees to the first axis 205. In an alternative example, the second axis 209 subtends an angle in the range 1-180 degrees to the first axis 205, although as will become apparent later, any angle can be used providing that the trimming beam 207 is then capable of trimming a portion of an item of manufacture. For example, the angle can be dictated by the disposition of components in a manufacturing line such that the selection of angle enables the optimum positioning of components in terms of either or both of item throughput and footprint/size minimisation. The power of the source beam is typically unaffected by having been reflected to provide the trimming beam, although a larger power for a source can be selected in order to provide a minimum power for a trimming beam as desired.

The system to alter the direction of the beam 203 can be implemented in any one of multiple alternative ways. In an example, the system 206 includes an angled mirror 211 mounted onto a rotating body 213. The angled mirror 211 can be angled relative to the first axis so that the source beam 203 reflects from its surface to form the trimming beam 207. In an example, rotating body 213 can be mounted onto support structure 109 such that the first axis to aligned to the main axis of rotation of the structure 109. The body 213 can be fixedly mounted to structure 109, or mounted so as to be independently movable with respect to the support.

Figure 3 is a schematic block diagram of a laser trimming system in which the rotating body is mounted onto a support structure. Structure 109 is a circular support structure with multiple support stations 111. Support stations 111 are configured to receive items to be trimmed 301 so that they are supported or otherwise held in place as the support rotates to convey items as is typical. Items to be trimmed 301 can be items of manufacture such as cans, tins, cups, components and so on.

Rotating body 213 includes a body portion 303 and a rotating portion 305.

In an example, body portion 303 is fixedly mounted to support structure 109 at the point wherein the main axis of rotation 304 of the support 109 is aligned with the first axis along which the source beam 203 travels.

Rotating portion 305 is rotatably mounted to body portion 303 and can be offset from body portion 303 using a spindle 307 for example. In an example, body portion 303 includes a controller 311 and a motor 313 which are operable to rotate the rotating portion 305. The axis of rotation of the rotating portion 305 is parallel to or aligned with the first axis and the thus also the main axis of rotation of the support 109, although other alternative alignments are possible. Body portion 303 may be offset from the main axis of rotation of the support if desired. The resulting eccentricity in path of the trimming beam as the support rotates can be accommodated by rotating portion using controller 311. Similarly, the source beam can be varied so that it consistently impinges on the irregularly placed body portion.

Rotating portion 305 can have mirror 211 mounted thereon. Alternatively, a prism can be mounted onto portion 305. In general, rotating portion 305 includes a device 315 to alter the direction of source beam 203. That is, the angled mirror 211 (or prism) for example are arranged to alter the direction of the source beam in order to provide the trimming beam.

In an example, laser source 201 is optically coupled to rotating body 213.

Therefore, the laser source 201 can be arranged to be fixed in relation to the body 213, or independently rotate or move provided that the source beam is operable to impinge onto body 213.

Figure 4 is a schematic diagram of a mode of operation of a laser cuffing system according to an example. In use, multiple items of manufacture are received into support stations 111 of support 109. For example, items 401 can be conveyed into support stations 111 at an input location, generally depicted at 403. Items 401 are conveyed by support 109 to an output location, generally depicted at 405 for further processing of the items downstream.

In an example, support 109 is arranged so that items 401 are conveyed by rotation of stations 111 around its main axis of rotation 407. As support rotates, items 401 can be rotated in their respective stations 111 around axes of rotation such as depicted by 409. In an example, rotation around axis 409 can be in any direction. Furthermore, it will be appreciated that items 401 can be offset from the vertical so that they are supported in stations 111 at an angle thereby resulting in an angle of rotation which is not parallel to axis 407. This will typically necessitate a variation in the trimming beam position as the item 401 rotates to account for the eccentricity in the position of the item as it rotates. In an example, this can be effected by altering the position of the source beam for example so that the angle of incidence with device 311 changes over time thereby altering the position of the trimming beam in the required way. The speed of rotation of the support 109 and items 401 in stations 111 can be varied.

Typically, a rate of rotation of an item in a station 111 will be greater than the rate of rotation of the support 109 as will become clear below.

Rotating body 213 is mounted onto support 109 so that source beam 203 impinges on rotating portion 305. By virtue of device 315, the direction of source beam 203 is altered, such as by reflecting the source beam 205 for example, to provide a trimming beam 207. Trimming beam 207 can be scanned through multiple exit stations by rotating the device 315 using the portion 305, which can be actuated by motor 313 and with a position and rate of rotation controlled using controller 311.

In an example, an exit station for trimming beam 207 corresponds to the position of a station 111 in support 109. Accordingly, at an exit station, trimming beam 207 impinges on an item to be trimmed being supported in a station 111 at a cutting point. By virtue of rotation of the item to be trimmed in the station 111, the trimming beam 207 trims a portion of the item. In an example, the trimmed portion corresponds to a circumferential region of an item such that any manufacturing irregularities are removed.

In an example, an item to be trimmed is tracked using the trimming beam 207 as the item is conveyed in the support 109. More specifically, as the support 109 rotates in order to convey an item from the input 403 to output 405, trimming beam 207 is rotated in unison with support 207 by rotating the device 315 using rotating portion 305. That is, controller 311 controls the rate of rotation of the rotating portion 305 in order to allow an item to be trimmed to be tracked far a predetermined amount of time. In an example, the tracking time is sufficient to allow an item to trimmed to be rotated in its station 111 by 360 degrees so that the cutting point of trimming beam 207 causes the entire circumference of the item to be cut, scored or trimmed.

In an alternative example, the tracking time is sufficient to allow enough of the item to be trimmed, cut or scored so that a desired portion can be easily removed. For example, in the case of a can, either the entire circumference can be trimmed, or a small portion can be left untrimmed. In the latter case, the trimmed portion can be removed by snapping the untrimmed portion so that the portion to be trimmed can be removed downstream.

Typically, the rate of rotation of an item in a station 111 is sufficient to allow the item to be trimmed in the desired way before the device 315 is reset to another exit station so that trimming of another item can be commenced.

The rate of rotation of an item in a station 111 and the rate of rotation of the support can be tuned to allow the desired throughput of items. At a maximum capacity, the rates of rotation are tuned so that no item exits without having been trimmed in the desired way. As mentioned, it will be typical for a rate of rotation of an item in a station 111 to be greater than that of the support 109 so that an item is trimmed and the trimming beam is reset to an exit station so that another item can be trimmed before it exits the support. Accordingly, there will be a minimum arc for the support which the trimming beam 207 must track an item to be trimmed through such that the trimming beam 207 returns to a position corresponding to the beginning of that arc at periodic intervals corresponding to the start of another trim process.

Figure 5 is a schematic diagram of a laser trimming system according to an example. A support 109 rotates around its main axis of rotation 407. An item to be trimmed 501 in a station 111 is thus conveyed by support 109 through an arc 503. An exit station for trimming beam 207 corresponds to a position 505 at which the item 501 can start to be trimmed. Accordingly, at position 505, the trimming beam 207 impinges on item 501, and beam 207 is rotated so as to track item 501 as it is conveyed in support 109 whilst being rotated in the station 111. For the period of time the item 501 is tracked it travels through an arc 507 which will typically have a length which is the less than arc 503 in order to enable multiple items to be trimmed in succession whilst in support 109 so that items do not remain the support any longer than necessary thereby maximising throughput for trimmed items.

Although depicted as circular, support 109 may be any shape as desired.

For example, it can be square or polygonal with a station 111 on each side.

In some example, a support station can include multiple levels to accommodate articles. Such articles can be offset relative to other articles in other levels to allow trimming using a single trimming system.

Device 315 has typically been described with reference to a mirror or prism.

It will be appreciated however that other suitable alternatives can be used.

For example, and with reference to figure 6 which is a schematic diagram of a laser scanning device according to an example, a cone shaped device can be used. The cone 600 can be a conical mirrored device or a multi-faceted cone shaped device for example. In the example of figure 6, the laser source 601 can be offset from the main axis of rotation of the support 109 as described above and can be translated so that the source beam is parallel to the main axis of rotation but impinges on the conical device 600 at positions which cause the source beam to reflect from its surface thereby resulting in the trimming beam. Similarly, the source 601 can be positioned in alignment with the main axis of rotation of the support but with its position adapted so the source beam is not parallel to the main axis of rotation and is directed to impinge on the conical device 600 at positions corresponding to those as described above and which cause the required reflection to form the trimming beam.

Figure 7 is a schematic block diagram of a system according to an example, and which is suitable for implementing and controlling any of the methods or processes described above. Apparatus 700 includes one or more processors, such as processor 701, providing an execution platform for executing machine readable instructions such as software. Commands and data from the processor 701 are communicated over a communication bus 799. The system 700 also includes a main memory 702, such as a Random Access Memory (RAM), where machine readable instructions may reside during runtime, and a secondary memory 705. The secondary memory 705 includes, for example, a hard disk drive 707 and/or a removable storage drive 730, representing a floppy diskette drive, a magnetic tape drive, a compact disk drive, etc., or a nonvolatile memory where a copy of the machine readable instructions or software may be stored. The secondary memory 705 may also include ROM (read only memory), EPROM (erasable, programmable ROM), EEPROM (electrically erasable, programmable ROM). In addition to software, data representing any one or more of data representing a desired rate of rotation for a support, station or rotation device may be stored in the main memory 702 and/or the secondary memory 705. The removable storage drive 730 reads from and/or writes to a removable storage unit 709 in a well-known manner.

A user can interface with the system 700 with one or more input devices 711, such as a keyboard, a mouse, a stylus, a touch screen device and the like in order to provide user input data for example. The display adaptor 715 interfaces with the communication bus 799 and the display 717 and receives display data from the processor 701 and converts the display data into display commands for the display 717. A network interface 719 is provided for communicating with other systems and devices via a network.

The system can include a wireless interface 721 for communicating with wireless devices in the wireless community.

It will be apparent to one of ordinary skill in the art that one or more of the components of the system 700 may not be included and/or other components may be added as is known in the art. The system 700 shown in figure 7 is provided as an example of a possible platform that may be used, and other types of platforms may be used as is known in the art.

One or more of the steps described above may be implemented as instructions embedded on a computer readable medium and executed on the system 700. The steps may be embodied by a computer program, which may exist in a variety of forms both active and inactive. For example, they may exist as software program(s) comprised of program instructions in source code, object code, executable code or other formats for performing some of the steps. Any of the above may be embodied on a computer readable medium, which include storage devices and signals, in compressed or uncompressed form. Examples of suitable computer readable storage devices include conventional computer system RAM (random access memory), ROM (read only memory), EPROM (erasable, programmable ROM), EEPROM (electrically erasable, programmable ROM), and magnetic or optical disks or tapes. Examples of computer readable signals, whether modulated using a carrier or not, are signals that a computer system hosting or running a computer program may be configured to access, including signals downloaded through the Internet or other networks. Concrete examples of the foregoing include distribution of the programs on a CD ROM or via Internet download. The same is true of computer networks in general. It is therefore to be understood that those functions enumerated above may be performed by any electronic device capable of executing the above-described functions.

According to an example, controller 311 is operatively coupled to apparatus 700. A control program 730 for controlling the operation of a support 109 can reside in memory 702 and operate on data from input sources for example such as to control a rate of rotation, an input and output position for items, and a rate of rotation for items in stations 111. Further, a laser scanning device rotation control module 731 can reside in memory 702 and be used to control the controller 311 so that motor 313 can be controlled to affect the rate of rotation of a scanning device for example.

It will be appreciated that the words "trim", "score" and "cut" have been used interchangeably throughout, and reference to any one term herein is not intended to be limiting.

Claims

CLAIMSWhat is claimed is: 1. A laser cutting system for trimming an item of manufacture, comprising: a rotatable support with multiple stations to receive multiple items to be trimmed; a laser scanning device to scan a laser trimming beam through multiple positions corresponding to exit stations for the device, the support to provide an item to be trimmed at an exit station and to rotate the item in its station in contact with the trimming beam to cut a portion of the item, wherein the trimming beam is derived from a source laser beam parallel to a first axis, the trimming beam parallel to a second axis which is different to the first.
2. A laser cutting system as claimed in claim 1, the support to rotate around the first axis while rotating an item to be trimmed around a third axis.
3. A laser cutting system as claimed in claim 2, the laser scanning device including: a laser source to provide the source beam for the system along the first axis; and a system to alter the direction of the laser source to form the trimming beam along the second axis.
4. A laser cutting system as claimed in claim 2, wherein the system to alter the direction of the laser source is independently rotatable around the first axis.
5. A laser cutting system as claimed in claim 3, wherein the system to alter the direction of the laser source is an angled mirror.
6. A laser cutting system as claimed in claim 1, the support to provide multiple items to be trimmed in rotatable succession at exit stations of the device.
7. A laser cutting system as claimed in claim 6, the laser scanning device to track an item to be trimmed at an exit station.
8. A laser cutting system as claimed in claim 7, wherein the laser scanning device tracks the item to be trimmed by rotating in unison with the support.
9. A laser scanning device suitable for use with a system as claimed in any of claims ito 8.
10. The laser scanning device as claimed in claim 9, wherein the system to alter the direction of the laser source is a prism or conical shaped mirror.
ii. A laser cuffing method in which a cuffing laser beam is applied to an item to be cut at a cuffing point, comprising: providing a source laser beam along a first axis; scanning the source laser beam through multiple positions corresponding to exit stations using a scanning device to provide a cutting beam along a second axis; providing an item to be cut at an exit station; and tracking the item using the cutting beam by rotating the exit station in unison with the item.
12. A laser cutting method as claimed in claim 11, wherein scanning the source laser beam includes reflecting the source laser beam from a rotatably mounted reflective surface.
13. A laser cutting method as claimed in claim 12, wherein the rotatably mounted reflective surface is a mirror mounted on a rotation device.
14. A laser cutting method as claimed in claim 11, wherein an item to be cut is supported on a rotating mount including multiple stations for receiving multiple items to be cut.
15. A laser cutting method as claimed in claim 14, wherein the rotating mount rotates around the first axis.
16. A laser cutting method as claimed in claim 11, wherein the axis of the cutting beam is orthogonal to the first axis.
17. A laser cutting method as claimed in claim 11, further comprising altering the cutting point as the item to be cut is tracked by the cuffing beam.
18. A computer program embedded on a non-transitory tangible computer readable storage medium, the computer program including machine readable instructions that, when executed by a processor, implement a method for controlling a laser trimming device, the method comprising: controlling power for a source laser beam; scanning the source laser beam through multiple positions corresponding to exit stations to provide a cutting beam using a motor; controlling the position of an item to be trimmed at an exit station; rotating the exit station, and tracking the item in the exit station using the cuffing beam using a controller.