Feeder replacement

Abstract

The feeders on the chip mounter can be automatically replaced according to a new protocol, the partially-exhausted feeders are temporarily moved into the external storage device from the slots of the feeders, the fully-replaced feeders are placed into the slots of the feeders, and the partially-exhausted feeders are returned to the standby slots of the chip mounter. The remaining elements of the partially depleted feeder are picked up from the spare slots.

Description

Technical Field

[0001] The present invention relates to a method for supplying SMT components in a feeder module to a placement machine during an SMT placement operation, and a method for replacing an exhausted feeder module on a placement machine during an SMT placement operation. Background Art

[0002] The present invention generally relates to the technical field of equipping component carriers, such as printed circuit boards (PCBs), substrates or workpieces, with electronic components in the so-called surface mount technology (SMT) process.

[0003] The production of electronic subassemblies is usually carried out using so-called placement machines, by means of which the electronic components are removed from a component supply in an automated manner and placed on a component carrier, such as a printed circuit board. The components are transferred from the component supply to their respective placement positions by means of component handling devices, such as so-called placement heads. In most cases, this transfer of components is carried out by means of a single handling device, usually referred to as a placement head.

[0004] The most common packaging method for small electronic components is to use a carrier tape, sometimes also called a "transport tape", on which small pockets are formed. A component is placed in each pocket. There is only one type of component in each carrier tape. In order to save space and facilitate transportation, the carrier tape is usually formed into a roll by winding it on a bobbin. Usually, the carrier tape roll is placed in a feeder module (usually referred to as a "feeder"), which includes a drive device that drives the carrier tape forward (such as a pin wheel driven by a motor and engaged with holes set in the length direction of the carrier tape), and a pick-up area or window for accessing components. The feeder can be removably inserted into the placement machine. The placement machine is provided with many parallel slots or tracks, each slot is configured to releasably receive a feeder. In this way, a placement machine can be equipped with multiple different feeders, each of which can provide a specific component to the placement machine.

[0005] Recently, a cartridge system has been proposed in which the roll is placed in a passive cartridge module or cassette, which can usually be a relatively cheap plastic container or a sleeve with a defined shape that is easily held by a robot, which can be loaded at a central filling station and then connected to a feeder module, which includes a drive device for pushing the carrier roll forward. As an alternative, if the placement machine itself is provided with a carrier drive mechanism, the cartridge module can be directly inserted into the placement machine along its slot. For example, an example of a cartridge and a feeder device is described in DE 102019127299.8. In such a system, the feeder unit can be used to drive the carrier tape located in the cartridge unit so as to move the components located in the carrier tape pocket to a pick-up area, in which the placement head of the placement machine can contact the components. Depending on the specific design, the pick-up area can be located inside the cartridge or inside the feeder.

[0006] For the placement machine to work, it must be possible to supply the placement machine with feeders (and / or cassettes, depending on the setup), including the corresponding carrier tapes.

[0007] This reconfiguration (i.e. equipping with different feeders / boxes) is currently a manual process that requires significant personnel input.

[0008] In the current standard manual refill method, known as "splicing", the carrier tape from which the placement machine picks the components is manually connected to a new carrier tape. In this process, the old carrier tape is unwound from the reel, connected (spliced) to the new carrier tape, and then reeled onto the new reel.

[0009] The process allows refilling to take place before it is needed. Refilling does not need to take place at a specific time, but rather within a defined period. This period is calculated and monitored by software (e.g. Siplace Line Monitor). This ensures a certain degree of separation between the processes, creating a continuous state for the refilling and filling processes. In this way, load peaks and troughs can offset each other to a certain extent.

[0010] In recent years, a lot of effort has been put into automating material replenishment and changeover.

[0011] Specific background technology may be mentioned in EP3419402A1. As described in the document, an external exchange device can be provided for transferring a feeder between a storage position and an operating position, the feeder having a feeding capacity and a material storage function, and the exchange device is operable to move along a production line with one or more placement machines parallel to the workpiece throughput direction. The exchange device is operable to translate along a track installed along the production line and supported by the track (therefore, the device can be called a "track-guided vehicle"). This method has various advantages, for example, the use of a guide rail mounted on the machine avoids any problems that may arise due to defects in the floor surface, because the exchange device is maintained in a fixed vertical position relative to the placement machine, and a high level of positioning accuracy can be achieved on the production line. One advantage of this system is that the track-guided vehicle can directly and possibly continuously draw power from the placement machine. However, this system also has various disadvantages. For example, a dedicated exchange device is required on each side of the production line, which may limit the placement distance of adjacent production lines. The described system also lacks flexibility, such as the inability to manage a barrel-based feeding system. This system has been found to be relatively slow and, due to the high demand for specialized equipment for each production line, also costly.

[0012] It has been recognised that a more flexible and potentially cheaper solution might be to equip an automated guided vehicle (AGV) with a feeder / barrel change mechanism. As is well known in the art itself, AGVs are small mobile robotic devices that can move across the floor, usually on a wheeled chassis, with at least some degree of autonomy. AGVs are available from many manufacturers (and are therefore relatively inexpensive, and line operators may already have a suitable AGV), and are often equipped with an upper platform that can carry specific equipment.

[0013] This approach allows for automation or automatic refilling through feeder exchange rather than through the manual splicing method described above. In such an automated process, the tapes and reels are stored and transported inside the feeders. The automated handling system handles the feeders directly, with the reels inside the feeders. In the automated process, a constant and specific feeder interface can be used for processing, simplifying the process compared to the manual splicing method of handling reels and tapes separately. The key component of the automated handling system is the exchange mechanism used to transfer the feeders between the placement machine and the separate storage location.

[0014] To refill material on a placement machine, the feeder is pulled from the track inside the machine by an automatic handling system / exchange mechanism and the new feeder replaces the old feeder at the same slot. To ensure that all components of the carrier tape are utilized, the slot can only be refilled after all components of the feeder have been picked up by the placement machine. This means that early refilling on the same track (which was possible in the manual follow-up process) is no longer possible.

[0015] With this automated process, the two main reasons for machine downtime (inability to make a pick) are: i) First, no components can be picked from the feeder associated with a track while the feeder for that track is being changed. This minimizes downtime by changing feeders faster.

[0016] ii) In addition, if the automatic handling system fails to replace the feeder on the track at the appropriate time (i.e., too late) so that the feeder runs out of components before the replacement, then downtime may occur. This occurs when multiple feeders (either on a placement machine or on a production line that includes one or more placement machines) run out at the same time. In this case, assuming that there is only a single automatic handling system on the line, the feeders can only be replaced one by one. Setting up additional automatic handling machines on the line may reduce this type of downtime, but this problem may still occur if more than two feeders run out at the same time. In addition, setting up additional automatic handling machines will significantly increase the cost of line operators.

[0017] Various measures have been taken to minimize downtime using automated processes. For example, EP23171095.5, as well as US11464145B2 and WO-A1-2020039543 of the present applicant describe a method of placing a new or replacement feeder (second feeder) on a spare track inside the same placement machine. After the components of the first feeder are exhausted, the machine can pick up components from the second feeder. This method can significantly reduce downtime and, if implemented properly, can prevent machine stagnation.

[0018] Figures 1A to 1F This approach is shown schematically.

[0019] Figure 1AA placement machine 1 is shown with a placement head 2 operable to pick up components from a feeder module located in any slot of the placement machine 2. Five slots are shown here, and in practice there will typically be more slots. Of these five slots, three slots 3A, 3B and 3C are "preferred slots" which are well positioned and are well suited for efficient placement operations, while slots 4A, 4B are "spare slots" which are poorly positioned and therefore result in inefficient placement operations when components are picked up from feeder modules in such spare slots. For example, if workpieces (not shown) to be placed are traveling through the placement machine 1 in a transport direction T, the placement positions of these workpieces within the placement machine 1 may be close to slots 3A-3C, so picking up from feeders in spare slots 4A, 4B will require the placement head 2 to make additional trips between the feeder module and the workpiece, and therefore require additional travel time.

[0020] The position of the placement head 2 next to the slot 3C indicates that it is currently picking from the feeder module located in that slot (i.e., the first feeder module "A"). Here, the first feeder module A has sufficient components, i.e., they have not been depleted by the placement operation to the extent that refilling is required or desired.

[0021] Figure 1B The start of the refilling operation is shown, which is triggered when the first feeder module A reaches a predetermined depletion level, as shown by the diagonal line on the first feeder module A. At this time, the mobile robot 5 moves to the placement machine 2 and aligns itself near the slots 3A to 3C, 4A, 4B. The mobile robot 5 includes a storage device 6 for temporarily retaining at least two feeder modules. The storage device 6 is movable along the X-axis relative to the base of the mobile robot 5, and when the mobile robot 5 is positioned to engage with the placement machine 1, the axis is generally parallel to the transport direction T. This relative movement enables the storage device 6 and the feeder modules retained thereby to be aligned relative to the slots 3A to 3C, 4A, 4B in a direction parallel to the transport direction T as required.

[0022] It should be noted that this alignment between the remaining feeder modules and the slots 3A to 3C, 4A, 4B can also be achieved in other ways. For example, the mobile robot 5 itself may be capable of precise movement along the X axis, in which case no relative movement of the storage device 6 is required. Alternatively, a switching mechanism (see below) can also be provided that enables the feeder modules to move parallel to the X axis when transferred between the storage device 6 and the placement machine 1.

[0023] like Figure 1BAs shown, the storage device 6 includes a plurality (three in this case) of storage slots 7A to 7C, each of which is configured to releasably receive a feeder module in use. As shown in the figure, the second feeder module B is accommodated inside the storage slot 7B, and the second feeder module B includes the same type of components as the first feeder module A. The storage device 6 is aligned with the mounter 1 so that the storage slot 7B is aligned with the spare slot (slot 4B in this example). If necessary, the storage device 6 is moved along the X-axis to achieve this alignment (not shown). At this stage, the pick-up head 2 continues to pick up components from the first feeder module A.

[0024] Then, as Figure 1C shown, the second feeder module B is transferred from the storage slot 7B to the spare slot 4B by the exchange mechanism 8. The exchange mechanism 8 is not shown in detail in the figure, but it includes a mechanical interface that can transfer the feeder module bidirectionally between the storage device 6 and the mounter 1 in directions parallel and orthogonal to the X-axis, for example, by engaging with the profile portion of the feeder module. For example, a simple type of exchange mechanism 8 can include a paddle that can engage with a groove provided on the feeder module, and the paddle is mounted on a conveyor belt that can be driven in either direction, so as to linearly push or pull the feeder module between the storage device 6 and the mounter 1. Exemplary exchange mechanisms are described in, for example, DE102021117281B3, DE102021119314B3, and EP2319433.5. The exchange mechanism 8 can be located on the mobile robot 5, on the mounter 1, or as a separate unit. At this stage, the pick-up head 2 continues to pick up components from the first feeder module A until the first feeder module A is completely depleted.

[0025] As Figure 1D shown, when the first feeder module A is completely depleted (as indicated by the two crossed lines in the feeder module A), the pick-up head 2 starts to pick up components from the second feeder module B in the spare slot 4B.

[0026] Then, as Figure 1E shown, the mobile robot 5 moves to the mounter 1. The storage device 6 is moved along the X-axis so that the empty storage slot (slot 7B in this case) is aligned with the slot 3C. At this stage, the pick-up head 2 continues to pick up components from the second feeder module B.

[0027] Then, as Figure 1F shown, the exchange mechanism 8 transfers the empty first feeder module A from the slot 3C to the storage slot 7B. At this stage, the pick-up head 2 continues to pick up components from the second feeder module B.

[0028] It can be seen that in Figures 1D to 1FIn the step shown, head 2 is picking from the second feeder module B while in spare slot 4B. This is a disadvantage of this type of approach. Typically, the feeder modules located in each slot are carefully selected to optimize placement speed so that, for example, a large number of components placed on a board can be located in slots that are close to the nominal "home" position of the head, thereby minimizing the travel time of head 2. If a feeder module is located in a spare slot, then obviously its position may not be optimized.

[0029] This under-optimization can be corrected by subsequently moving the second feeder module B to the optimal slot, i.e. the original position of the first feeder module A (here slot 3C), once the first feeder module A is empty. Figures 1G to 1J As will become clear from the following description, such a move will require a stop during which the components associated with the feeder module must not be picked up. There is at least some flexibility in the timing of the move so that it can be performed at a relatively convenient time, reducing the impact on throughput, but in any case such a stop is unavoidable.

[0030] like Figure 1G As shown, the storage device 6 moves leftward along the X axis, as shown in the figure, until the empty storage slot (here 7C) is aligned with the spare slot 4B. At this stage, the placement head 2 continues to pick up from the second feeder module B.

[0031] Then, if Figure 1H As shown, the exchange mechanism 8 transfers the second feeder module B to the slot 7C of the storage device 6. At this stage, no picking occurs.

[0032] like Fig. 1I As shown, the storage device 6 moves to the right along the X-axis, as shown, until the storage slot 7C is aligned with the slot 3C. The exchange mechanism 8 can then transfer the second feeder module B into the slot 3C. At this stage, no picking occurs.

[0033] Finally, if Figure 1J As shown, the placement head 2 can restart picking from the second feeder module B in the slot 3C. The mobile robot 5 is free to move away as needed and transport the empty first feeder module A to a collection station (not shown) for refilling when appropriate. Summary of the invention

[0034] The present invention is directed to an automatic refill system and method that can be managed by an economically reasonable number of automatic processing machines or exchange units while minimizing downtime.

[0035] According to the present invention, this object is achieved by replacing a depleted feeder module and thereby supplying the SMT components in the feeder module to a new process of a placement machine.

[0036] According to a first aspect of the present invention, there is provided a method for supplying SMT components inside a feeder module to a placement machine during an SMT placement operation, the placement machine comprising a plurality of slots, each slot being configured to releasably receive a feeder module in use, and a first slot of the plurality of slots receiving a first feeder module, the first feeder module containing a plurality of SMT components exhausted during the SMT placement operation; the method comprising the following steps: i) providing an exchange unit, the exchange unit comprising a storage device for temporarily retaining at least two feeder modules, wherein the storage device is provided with a second feeder module, the second feeder module containing SMT components of the same type as the first feeder module; ii) before the SMT components of the first feeder module are completely exhausted, transferring the first feeder module from the first slot to the storage device; iii) transferring the second feeder module from the storage device to the first slot; and iv) transferring the first feeder module from the storage device to a second slot of the plurality of slots of the placement machine.

[0037] According to a second aspect of the present invention, there is provided a method for replacing a feeder module exhausted on a placement machine during an SMT placement operation, the placement machine comprising a plurality of slots, each slot being configured to releasably receive a feeder module in use, and a first slot of the plurality of slots receiving a first feeder module, the first feeder module containing a plurality of SMT components exhausted during the SMT placement operation; the method comprising the following steps: i) providing a switching unit, wherein the switching unit comprises: A storage device for temporarily retaining at least two feeder modules, wherein the storage device is provided with a second feeder module, the second feeder module containing SMT components of the same type as the first feeder module; ii) before the SMT components of the first feeder module are completely exhausted, transferring the first feeder module from the first slot to the storage device; iii) transferring the second feeder module from the storage device to the first slot; and iv) transferring the first feeder module from the storage device to a second slot of the plurality of slots of the placement machine.

[0038] Further particular aspects and features of the invention are set out in the accompanying claims.

[0039] For the purposes of the present invention, the term "feeder module" means any of the following: a) a feeder, i.e. a single module carrying a component carrier reel and a drive for advancing the carrier reel; or b) A magazine module that carries a component carrier tape reel but has no drive device, for interfacing with a separate feed module or directly with a placement machine that includes a carrier tape drive device.

[0040] The term "mobile robot" as used herein includes automatic guided vehicles (AGVs), track-guided vehicles (RGVs) (which are mobile robots that can move along tracks carried by or near placement machines, as described above), autonomous intelligent vehicles (AIVs), and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The invention will now be described with reference to the accompanying drawings (not to scale), in which:

[0042] Figures 1A to 1J The steps of a known feeder module replacement method are schematically shown.

[0043] FIG. 2A to FIG. 2J The steps of the feeder module replacement method according to the present invention are schematically shown.

[0044] Description of reference numerals: 1 - Chip Mounter 2 - Placement head 3A to 3C - Preferred Slots 4A, 4B - Spare slots 5 - Mobile Robot 6 - Storage Devices 7A to 7C - Storage slots 8 - Exchange Agency 9 - Storage Conveyor A - First Feeder Module B - Second Feeder Module T - Transmission direction X - Horizontal axis. DETAILED DESCRIPTION

[0045] FIG. 2A to FIG. 2J The steps of the feeder module replacement method according to the present invention are schematically shown. Figures 1A to 1J Similar devices are shown and described, so for simplicity the relevant reference numerals have been retained.

[0046] Figure 2AA placement machine 1 is shown with a placement head 2 operable to pick up components from a feeder module located in any slot of the placement machine 1. Five slots are shown here, and in practice there will typically be more slots. Of these five slots, three slots 3A, 3B and 3C are "preferred slots" which are well positioned and are well suited for efficient placement operations, while slots 4A, 4B are "spare slots" which are poorly positioned and therefore result in inefficient placement operations when components are picked up from feeder modules in such spare slots. For example, if workpieces (not shown) to be placed are moved through the placement machine 1 in a transport direction T, the placement positions of these workpieces within the placement machine 1 may be close to slots 3A to 3C, so picking up from feeders in spare slots 4A, 4B will require the placement head 2 to make additional moves between the feeder module and the workpiece, and therefore require additional travel time.

[0047] The position of the placement head 2 next to slot 3C indicates that it is currently picking from the feeder module located in that slot (i.e., the first feeder module "A"). Here, the first feeder module A has sufficient components, i.e., they have not been depleted by the placement operation to the extent that refilling is required or desired.

[0048] Figure 2B The start of a refill operation is shown, which is triggered when the first feeder module A reaches a predetermined depletion level, as shown by the diagonal line on the first feeder module A. There are a number of ways to determine the predetermined depletion level of feeder module A. For example: i) The depletion time of the first feeder module A may be determined, after which the SMT components of the first feeder module A are completely depleted. A predetermined depletion level may then be defined as a depletion level that occurs after a predetermined sub-range of the determined depletion time. For example, if the predetermined depletion level is set to occur after 70% of the depletion time, and the depletion time of the feeder module is determined to be 10 minutes, the predetermined depletion level will occur after 7 minutes. At this point, the refill operation is triggered. The depletion time of feeder module A may be determined in a variety of ways, such as: knowing the initial number of SMT components remaining in feeder module A and analyzing the usage of these SMT components during the placement operation; calculating the number of SMT components picked up; or analyzing the number of SMT components required for each workpiece to be placed and calculating the number of workpieces so placed; or ii) The number of SMT components remaining in the first feeder module A can be determined, and when the number of remaining SMT components retained by the feeder module A is below a set number, a predetermined depletion level is set. Similarly, the number of SMT components remaining in the first feeder module A can be determined by: knowing the initial number of SMT components retained in the feeder module A and analyzing the use of these SMT components during the placement operation; calculating the number of SMT components picked up; or analyzing the number of SMT components required for each workpiece to be placed and calculating the number of workpieces so placed. When the determined number of SMT components remaining in the first feeder module is below a threshold, a refill operation will be started.

[0049] At this point, the mobile robot 5 (i.e., the exchange unit used in this embodiment) moves to the placement machine 2 and aligns itself near the slots 3A to 3C, 4A, 4B. The mobile robot 5 includes a storage device 6 for temporarily retaining at least two feeder modules. The storage device 6 is movable along the X-axis relative to the base of the mobile robot 5, and when the mobile robot 5 is positioned to engage with the placement machine 1, the axis is generally parallel to the transport direction T. This relative movement enables the storage device 6 and the feeder modules retained thereby to be aligned relative to the slots 3A to 3C, 4A, 4B in a direction parallel to the transport direction T as required.

[0050] It should be noted that this alignment between the retained feeder modules and the slots 3A to 3C, 4A, 4B can also be achieved in other ways. For example, the mobile robot 5 itself may be capable of precise movement along the X axis, in which case no relative movement of the storage device 6 is required. Alternatively, a switching mechanism (see below) can also be provided that enables the feeder module to move parallel to the X axis when transferred between the storage device 6 and the placement machine 1.

[0051] like Figure 2B As shown, the storage device 6 includes a plurality of (here three) storage slots 7A to 7C, each storage slot 7A to 7C being configured to releasably receive the feeder module being used. As shown, the second feeder module B is accommodated inside the storage slot 7B, and the second feeder module B contains the same type of components as the first feeder module A. The storage device 6 is aligned with the placement machine 1 so that the empty storage slot (here storage slot 7C) is aligned with the slot 3C where the first feeder module A is located. If necessary, the storage device 6 is moved along the X-axis to achieve this alignment (not shown). At this stage, the placement head 2 continues to pick from the first feeder module A.

[0052] Then, if Figure 2CAs shown, the first feeder module B is transferred from the slot 3C to the storage slot 7C by the exchange mechanism 8. The exchange mechanism 8 is not shown in detail in the figure, but it includes a mechanical interface that can, for example, bidirectionally transfer the feeder module between the storage device 6 and the placement machine 1 in directions horizontal to and orthogonal to the X-axis by engaging with the contour portion of the feeder module. For example, a simple type of exchange mechanism 8 may include a paddle that can engage with a groove provided on the feeder module, and the paddle is mounted on a transmission belt that can be driven in either direction, so that the feeder module is pushed in or pulled out linearly between the storage device 6 and the placement machine 1. For example, exemplary exchange mechanisms are described in DE102021117281B3, DE102021119314B3 and EP2319433.5. The exchange mechanism 8 can be located on the mobile robot 5, on the placement machine 1, or as a separate unit. At this stage, the placement head 2 cannot perform a picking operation.

[0053] like Figure 2D As shown, the storage device 6 moves along the X axis so that the storage slot 7B of the second feeder module B that remains full is aligned with the currently empty slot 3C. At this stage, the placement head 2 cannot perform a picking operation.

[0054] Then, if Figure 2E As shown, the exchange mechanism 8 transfers the full second feeder module B from the storage slot 7B to the slot 3C. At this stage, the placement head 2 cannot perform the picking operation until the second feeder module B is completely transferred to the slot 3C.

[0055] like Figure 2F As shown, the storage device 6 is moved along the X axis so that the storage slot 7C (retaining the partially depleted first feeder module A) is aligned with a spare slot (4B in this case) that provides slightly more economical picking than the other spare slot 4A. At this stage, the placement head 2 can continue to pick from the second feeder module B if necessary.

[0056] Then, if Figure 2G As shown, the exchange mechanism 8 transfers the partially exhausted first feeder module A from the storage slot 7C to the spare slot 4B. At this stage, the placement head 2 continues to pick up from the second feeder module B.

[0057] like Figure 2H As shown, the placement head 2 can restart picking from the first feeder module A in the spare slot 4B. The mobile robot 5 can move away freely as needed.

[0058] like Fig.2IAs shown, once the first feeder module A is completely exhausted (as shown by the two crossed lines in feeder module A), the placement head 2 can restart picking from the second feeder module B in slot 3C.

[0059] Finally, if Figure 2J As shown, the mobile robot 5 moves to a position close to the placement machine 1 and the storage device 6 moves along the X-axis so that the empty storage slot (7C in this case) is aligned with the spare slot 4B. The exchange mechanism 8 then transfers the empty first feeder module A from the spare slot 4B to the storage slot 7C. At this stage, the placement head 2 continues to pick from the second feeder module B. The mobile robot 5 is free to move away as required and transport the empty first feeder module A to the collection station (not shown) for refilling when appropriate. This step can be performed when it is convenient - since the second feeder module B still has a good filling level, there is no immediate urgency to collect the empty first feeder module A. This means that the mobile robot 5 can perform other, possibly more urgent jobs at the same time.

[0060] It can be seen that the various advantages of the current method compared to the previous method shown in Figure 1 are: - The mobile robot can perform the refilling task before the components of the feeder module are exhausted. Therefore, the time dependency can be reduced and the performance requirements of the refilling process can be lowered. The simulation results show that for a smartphone customer with 11 placement machines on the production line, two robots are required to perform all refilling tasks in time using the previous method, that is, to replace the feeder modules on time, while the number of robots can be reduced to one using the current method; - Reduced time dependencies make the refilling process more robust to disturbances of automated handling and production flows. An example of such a machine disturbance is if there are two feeder module exchange events within a short time, then the prediction has to decide which feeder module should be replaced first. However, disturbances such as picking errors can lead to incorrect predictions. As a result, the mobile robot might move to the wrong position, resulting in longer downtimes. The same applies to disturbances that affect the refilling process (e.g. workers in the aisle, etc.); - Reducing the time dependency can reduce the prediction accuracy of feeder module exchange events; - Mobile robots are freed up from the production line; as more spare tracks are used on the line, mobile robots will have larger blocks of “idle time” and can be used to support other line tasks, changeovers, battery charging, etc.; and Compared with previous methods, the track unavailability time is shortened.

[0061] The above embodiments are exemplary only, and other possibilities and alternatives within the scope of the invention will be apparent to those skilled in the art. For example, several steps may be combined. For example, while or before or after the mobile robot transfers a partially depleted first feeder module to a spare slot, it can pick up any empty feeder modules that may be present in other spare slots, such as feeder modules emptied in a previous refilling operation.

[0062] In the above described embodiment, the exchange unit comprises a mobile robot, which comprises a storage device. However, the invention is not limited to this, and other types of exchange units, each of which comprises a storage device, may also be used. For example, a known exchange unit is at least temporarily retained on the placement machine. Such an exchange unit can be placed on the placement machine by a mobile robot, which can be moved away when the exchange unit performs the required feeder module transfer, or can be moved along the side of the placement machine as required (for example a so-called "track-guided vehicle"), or simply placed next to the placement machine (similar to the well-known die change table) (optionally by an operator). In all cases, the exchange mechanism can be arranged as part of the exchange unit, as part of the placement machine, or as a separate unit.

Claims

1. A method for supplying SMT components inside a feeder module to a placement machine during an SMT placement operation, the placement machine comprising a plurality of slots, each slot being configured to releasably receive a feeder module in use, and a first slot of the plurality of slots receiving a first feeder module, the first feeder module containing a plurality of SMT components consumed during the SMT placement operation; the method comprising the following steps: i) providing an exchange unit, the exchange unit comprising a storage device for temporarily retaining at least two feeder modules, wherein the storage device is provided with a second feeder module, the second feeder module containing SMT components of the same type as the first feeder module; ii) starting a refilling operation, including transferring the first feeder module from the first slot to the storage device before the SMT components of the first feeder module are completely exhausted; iii) continuing the refilling operation by transferring the second feeder module from the storage device to the first slot; and iv) transferring the first feeder module from the storage device to a second slot of the plurality of slots of the placement machine.

2. The method according to claim 1, wherein: Step i) includes: setting up a switching mechanism, which is operable to transfer a feeder module from one of the multiple slots of the placement machine to the storage device, and transferring a feeder module from the storage device to one of the multiple slots of the placement machine; in steps ii), iii) and iv), transferring the first feeder module and the second feeder module through the switching mechanism.

3. The method according to claim 2, wherein: The storage device includes a plurality of storage slots, each storage slot being configured to releasably receive a feeder module in use, and wherein the switching mechanism is operable to transfer a feeder module from one of the plurality of slots of the placement machine to a storage slot, and to transfer a feeder module from a storage slot to one of the plurality of slots of the placement machine.

4. The method according to claim 2, wherein: The switching unit includes the switching mechanism.

5. The method according to claim 2, wherein: The chip placement machine includes the switching mechanism.

6. The method according to claim 1, wherein: Step iii) comprises: using a placement head of the placement machine to pick up an SMT component from the second feeder module in the first slot.

7. The method according to claim 1, comprising the steps of: v) picking up an SMT component from the first feeder module in the second slot using a placement head of the placement machine.

8. The method according to claim 7, comprising the steps of: vi) when the SMT components of the first feeder module are completely exhausted, picking up SMT components from the second feeder module in the first slot using the placement head of the placement machine.

9. The method according to claim 8, comprising the steps of: vii) transferring said completely exhausted first feeder module from said second slot to said storage means.

10. The method according to claim 1, wherein: Step ii) comprises: determining an exhaustion time of the first feeder module, at which the SMT components of the first feeder module are completely exhausted, and starting the refilling operation within a predetermined sub-range of the determined exhaustion time.

11. The method according to claim 1, wherein: Step ii) comprises: determining the number of SMT components remaining in the first feeder module, and starting the replenishing operation when the determined number of SMT components remaining in the first feeder module is lower than a threshold value.

12. The method according to claim 1, wherein: The exchange unit comprises a mobile robot.

13. The method according to claim 12, wherein: The mobile robot includes one of an automatic guided vehicle, a track-guided vehicle, and an autonomous intelligent vehicle.

14. The method according to claim 1, wherein: The feeder module includes a feeder.

15. The method of any one of claims 1 to 13, wherein the feeder module comprises a cartridge module.

16. A method for replacing a feeder module exhausted on a placement machine during an SMT placement operation, the placement machine comprising a plurality of slots, each slot being configured to releasably receive a feeder module in use, and a first slot of the plurality of slots receiving a first feeder module, the first feeder module containing a plurality of SMT components exhausted during the SMT placement operation; The method comprises the following steps: i) providing a switching unit, wherein the switching unit comprises: A storage device for temporarily retaining at least two feeder modules, wherein the storage device is provided with a second feeder module, the second feeder module containing SMT components of the same type as the first feeder module; ii) before the SMT components of the first feeder module are completely exhausted, transferring the first feeder module from the first slot to the storage device; iii) transferring the second feeder module from the storage device to the first slot; and iv) transferring the first feeder module from the storage device to a second slot of the plurality of slots of the placement machine.

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