Transport System

Abstract

To provide a transfer system suitable to enable automatic provision of feeders / cartridges, and capable of performing set-up changes and / or replenishment changes.SOLUTION: A transfer system for transferring items between a vehicle and a receptacle of a machine, comprises a vehicle-side positioning dock mounted to the vehicle, an engagement actuator, and a storage unit for storing at least one item. The storage unit is movably mounted on the vehicle, and includes a front face that is adapted to lie adjacent to the receptacle, a vehicle-side positioning member and a machine-side positioning member. The engagement actuator is operative to move the storage unit between a retracted position in which the vehicle-side positioning member engages with the vehicle-side positioning dock to position the storage unit relative to the vehicle, and a transfer position in which the machine-side positioning member may engage with a machine-side positioning dock located proximate the receptacle to position the storage unit relative to the machine.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a transfer system for transferring an article between a transport vehicle and a receiving seat of a machine, an automated guided vehicle, and a method for transferring an article from the transport vehicle to a receiving seat of a machine. [Background technology]

[0002] The present invention relates generally to the technical field of mounting electronic components on component carriers such as printed circuit boards (PCBs), substrates or workpieces in the so-called Surface Mount Technology (SMT) process.

[0003] Typically, such electronic subassemblies are manufactured using so-called placement machines, whereby electronic components are automatically picked from a component feeder and placed onto a component carrier, such as a printed circuit board, and a component handling device, such as a so-called placement head, is used to transport the components from the component feeder to their respective placement locations.

[0004] The most common packaging method for small electronic components uses a carrier tape, sometimes called a "belt," with several small pockets formed into it. Each pocket holds one component. Each carrier tape contains only one type of component. To save space and ease transportation, carrier tapes have traditionally been formed as reels wound on a spool. The tape reel is typically housed in a feeder module that includes a drive means for advancing the tape, such as a motor-driven pin gear that engages holes along the length of the carrier tape, and a pick-up or opening that provides access to the components. The feeder module can be removably inserted into the placement machine.

[0005] Relatively recently, cartridge systems have been proposed in which the reels are housed in passive cartridge modules or cassettes, which may conveniently be relatively inexpensive plastic containers or receptacles of a predefined shape that can be easily held by a robot, and which can be loaded at a central filling station and then inserted into the feeder. Alternatively, the cartridge modules can be inserted directly into the placement machine, if the placement machine itself is equipped with a tape drive. Examples of cartridge and feeder configurations are described in US Pat. No. 5,399,991. In such systems, the feeder unit can be used to drive the carrier tape, which is located in the cartridge unit, so that the components in the pockets of the carrier tape are moved to a pick-up area where they can be accessed by the placement head of the placement machine. Depending on the respective design, the pick-up area can be located in the cartridge or in the feeder.

[0006] For the operation of the placement machine, it is necessary to be able to feed the feeders (and / or cartridges, depending on the setup) including their respective carrier tapes to the placement machine. While in high throughput operations the supply of components is more or less continuous, such as in smartphone manufacturing, other electronics manufacturing processes are characterized by frequent setup changes of feeders and / or cartridges, requiring a wholesale change or replacement of feeders and / or cartridges. As used herein, a "setup change" refers to a wholesale change of feeders or cartridges associated with a placement machine. In contrast, a "replenishment change" refers to a feeder and / or cartridge replacement at the placement machine when components are out of stock or approaching out of stock, with minimal interruption to the supply of components.

[0007] On-line material (i.e. carrier tape) reloading and tool change (i.e. mounting a different feeder / cartridge) are currently labor-intensive manual processes. There have already been many efforts for the automation of material replenishment and changeover for some years now.

[0008] As a specific background art, reference may be made to US Pat. No. 5,399,633. As described therein, an external exchange device may be provided for transporting a feeder with a feeding capacity and a material storage between a storage location and a work location, the exchange device being operable to move parallel to the direction of throughput of the workpieces along a production line with one or more placement machines. The exchange device is operable to move parallel to a rail mounted along the production line and is supported by the rail (so the device can be called a "rail-guided transport vehicle"). Such an approach has various advantages. The exchange device is held in a fixed vertical position with respect to the placement machine, for example the use of machine mounting rails avoids problems that may arise due to floor irregularities and further allows a high level of positioning accuracy along the production line. However, such a system also has various disadvantages associated with it. For example it requires the use of a dedicated exchange device on each side of the production line, which may limit how close the lines can be. The system described is also inflexible, for example it cannot accommodate cartridge-type feeding systems. The system is relatively slow and also expensive, as dedicated equipment for each production line is often required.

[0009] It has been found that there may be a more flexible and potentially cheaper solution to equip automated guided vehicles (AGVs) with a feeder / cartridge change mechanism. As is well known to those skilled in the art, AGVs are small mobile robotic devices that can move around on a floor on a wheeled chassis, usually with at least some degree of autonomy. AGVs are available from a number of manufacturers (and therefore relatively cheap, and production line workers may already have a suitable AGV) and usually have a top platform on which job-specific equipment can be mounted. Figure 1 shows a schematic diagram of a conventional AGV 1, with the chassis 2, wheels 3 and platform 4 highlighted. Unfortunately, the use of AGVs for feeder / cartridge changeovers is problematic, since the positioning accuracy of AGVs is generally not as high as that required for feeder / cartridge changeovers on placement machines. Even if additional measures are provided to improve accuracy, this generally results in additional time required for correct positioning, which creates unacceptable delays. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] DE 102019127299 [Patent Document 2] European Patent Application Publication No. 3419402 Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention aims to provide a cost-effective, robust and fast transport system suitable for enabling automated feeding of feeders / cartridges, which can be implemented, for example, using commercially available AGVs (although custom-built AGVs and even track-guided vehicles could also be used), and which can handle either setup and / or refill rotation. According to the present invention, this is achieved by using a mechanical positioning system in conjunction with a storage, such as a feeder / cartridge storage, which can be mounted on the AGV platform.

[0012] In this specification, the following terms are used for convenience, each having the following meaning:

[0013] "Feeder" is understood to encompass feeders including a tape reel storage section and a drive means for advancing the carrier tape, as well as modular cartridge-feeder systems in which the tape reel storage section and the drive means are located in separate mating cartridge and feeder components.

[0014] X, Y and Z are used according to industry convention. The X-axis is parallel to the direction of transport of the workpiece along the production line, is approximately horizontal, and increases downstream; The Y axis is perpendicular to the X axis and increases approximately horizontally towards the placement machine; The Z-axis is perpendicular to the X-axis and Y-axis, is generally vertical, and increases in the upward direction. [Means for solving the problem]

[0015] According to a first aspect of the invention, there is provided a transfer system for transferring articles between a transport vehicle and a receiving seat of a machine, comprising: An engagement actuator; A storage unit for storing at least one article to be used, the storage unit being movably mounted on the transport vehicle to be used and including a front surface adapted to be adjacent to the receiving seat to be used and a machine side positioning member; Equipped with A transport system is provided in which an engagement actuator operates to move a storage unit between a retracted position in which the storage unit is at a first location relatively close to the transport vehicle and a transport position in which the storage unit is at a second location relatively far from the transport vehicle and a machine-side positioning member can engage with a machine-side positioning dock located close to a receiving seat to position the storage unit relative to the machine.

[0016] According to a second embodiment of the present invention there is provided an automated guided vehicle including a transport system according to the first aspect.

[0017] According to a third aspect of the present invention, there is provided a method for transferring an article from a transport vehicle to a receiving seat of a machine, comprising the steps of: i) providing a machine-side positioning dock adjacent to the receiving seat; ii) providing a transport system of the first aspect on a vehicle with at least one item in a storage unit; iii) moving the vehicle adjacent to the machine with the storage unit in its retracted position; iv) moving the storage unit to its transfer position such that the machine-side positioning member engages with the machine-side positioning dock; v) transferring the items from the storage unit to a receiving seat; A method is provided that includes:

[0018] Other particular aspects and features of the present invention are defined in the accompanying claims.

[0019] The invention will now be described with reference to the accompanying drawings (not to scale). [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic perspective view of a conventional AGV. [Diagram 2]FIG. 1 is a schematic perspective view of an AGV fitted with a transport system according to the invention, with various parts omitted for clarity; [Diagram 3] FIG. 2 is a schematic perspective view of a machine-side receiving seat. [Figure 4] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Diagram 5] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Figure 6] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Figure 7] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Figure 8] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Figure 9] FIG. 3 is a schematic perspective view of a transfer sequence for feeder replenishment using the AGV and transfer system of FIG. [Figure 10] FIG. 13 is a schematic perspective view of a transfer sequence for setup exchange. [Figure 11] FIG. 13 is a schematic perspective view of a transfer sequence for setup exchange. [Figure 12] FIG. 13 is a schematic perspective view of a transfer sequence for setup exchange. [Figure 13] 1 is a schematic perspective view of a transport system according to another embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In the following, an embodiment of the present invention will be described with reference to FIG. 2, which is a schematic perspective view of an AGV 10 fitted with a transport system 11 according to the invention, with various parts omitted for clarity. More specifically, the transport system 11 shown is adapted for replenishment of articles, i.e. in this embodiment, feeders, with ad-hoc exchange of articles. In FIG. 2, the transport system 11 is shown with its storage units (replenishment feeder storage units 18, as described below) in a retracted position, allowing the AGV 10 to move safely through the facility. The AGV 10 and the transport system 11 can be controlled by a comprehensive control system (not shown) that controls the placement process. The control system, consisting of suitably programmed computing or processing means, can be located on the production line in which the placement machine is included or elsewhere, and optionally the control system can be distributed among various on-site and remote locations. In any case, the AGV 10 and the transport system 11 can communicate with the control system wirelessly, as will be known per se to those skilled in the art.

[0022] The AGV 10 is generally of standard form, with a chassis 12 on which a flat platform 13 rests and is supported. Wheels 14 allow the AGV 10 to move along the ground surface, preferably caster-type wheels that can rotate 360° about their respective vertical axes, allowing the AGV 10 to move in any horizontal direction along the ground surface, so that it can directly approach a machine (not shown). For the safety of the machine and the personnel (not shown) who may be present near the AGV 10, a mark (not shown) may be placed on one end of the AGV 10 to indicate a nominal "front end" of the AGV 10. As a consistent definition throughout this specification, the front-to-rear direction of the AGV 10 when it is positioned adjacent to a machine being prepared for or being transferred is taken as the X-direction, the Z-axis is vertical, and the Y-axis, parallel to the direction between the sides of the AGV 10, increases toward the machine. These axes are as shown in FIG. 2.

[0023] In use, the transport system 11 is mounted to a platform 13 and moves with the AGV 10. More specifically, an engagement actuator comprising a plurality (here four) pivot legs 16 is fixedly mounted to the platform 13 such that each pivot leg 16 is fixed at one end to the platform 13 whilst being capable of pivoting about a respective horizontal axis parallel to the X-axis. Only three pivot legs 16 are visible in Figure 2. The engagement actuator also comprises motors (not shown) operative to pivot the pivot legs 16 about their respective pivot axes.

[0024] The distal end of each pivot leg 16 is pivotally connected to a table 17 which provides a flat surface on which a replacement feeder storage unit 18 is supported. The replacement feeder storage unit 18 takes the form of a tray adapted to hold at least two feeders 15 (only one feeder 15 is shown for clarity), which are positioned in an upright, side-by-side position by providing feeder engagement tracks 19 at the base of the replacement feeder storage unit 18. It should be noted that only some of the feeder engagement tracks 19 are shown for clarity. The feeder engagement tracks 19 are engageable with and allow each feeder 15 to move relative thereto in a direction parallel to the illustrated Y-axis. To be able to store both a replacement feeder full of parts and the empty feeder it replaces, space for at least two feeders is required. The replacement feeder storage unit 18 is defined by its front-to-back width, i.e., side walls 20 along the X-axis. The refill feeder storage unit 18 is movably mounted on a table 17 which can be driven by a linear actuator system in a direction parallel to the front of the transport system, i.e. parallel to the X-axis. The illustrated linear actuator system comprises a worm screw 21 which is attached to the table 17 extending in the X-direction and which engages with a gear 22 attached to the refill feeder storage unit 18. An actuator (not shown) acts to rotate the worm screw 21, thereby enabling the refill feeder storage unit 18 to move parallel to the X-axis.

[0025] The transport system also comprises an article moving unit (here a feeder moving unit) which operates to move the articles, i.e. the feeders, from the refill feeder storage unit 18 to the receiving seats of the placement machine (not shown in FIG. 2). The illustrated feeder moving unit is a two-stage arm, which is obvious to the person skilled in the art and does not need to be described in detail here, but in brief, the feeder moving unit comprises a paddle 25 adapted to abut against each feeder 15, which is driven to move in a direction perpendicular to the front face, i.e. parallel to the Y axis, thereby urging the feeder 15 towards the machine in use, and optionally also away from the machine if the machine does not have a feeder removal mechanism. The paddle 25 is here attached to a drive such as a belt drive of the feeder moving unit or a rack and pinion drive as shown in FIG. 2. More specifically, the paddle 25 is attached to a lower rack 26 of the double rack, together with an upper rack 27 also included in the double rack 26, both of which are attached to an arm 28 via a pinion (not shown in FIG. 2). The arm 28 is drivingly connected to a paddle actuator, here in the form of a drive belt 30. At least the paddle 25, and here the entire feeder moving unit, is also movable relative to the refill feeder storage unit 18 in a horizontal direction parallel to the front surface, i.e. parallel to the X-axis, so that in use it can abut against a selected feeder 15 from among the feeders lined up in the refill feeder storage unit 18. Further details of the feeder moving unit are described below with reference to FIG. 4.

[0026] The table 17 is mounted in a storage frame having a depth (along the Y axis) approximately equal to the width of the AGV 10. In the machine side area (the side with the larger Y value), the storage frame 23 has at least one machine side positioning member 24, and as shown in the figure, has two machine side positioning members: a machine side positioning member 24A located at the front end of the storage frame 23 and a machine side positioning member 24B located at the rear end of the storage unit. The machine side positioning members 24A and 24B protrude downward from the storage frame 23. In the transport vehicle side area, the storage frame 23 has at least one transport vehicle side positioning dock, which here includes a front transport vehicle side positioning dock 31A located at the front end of the storage frame 23 and a rear transport vehicle side positioning dock 31B located at the rear end of the storage frame 23. The front and rear transport vehicle side positioning docks 31A and 31B each protrude upward from the storage frame 23 with an upward opening. The form and function of these positioning members and docks are described in further detail below.

[0027] The front upright frame member 32 and the rear upright frame member 33 are fixedly attached to the chassis 12. Each of these upright frame members 32, 33 has a downwardly protruding positioning member, of which the front upright frame member 32 has a front vehicle-side positioning member 34A (not visible in FIG. 2) and the rear upright frame member 33 has a rear vehicle-side positioning member 34B. The front vehicle-side positioning dock 31A is designed to exactly receive the front vehicle-side positioning member 34A, and the rear vehicle-side positioning dock 31B is designed to exactly receive the rear vehicle-side positioning member 34B. When the transport system 11 is in the retracted configuration shown in FIG. 2 and the refill feeder storage unit 18 is in a first location relatively close (in the Y direction) to the AGV 10, the front transport vehicle side positioning member 34A engages in the front transport vehicle side positioning dock 31A and the rear transport vehicle side positioning member 34B engages in the rear transport vehicle side positioning dock 31B.

[0028] The engagement actuators operate to move the replacement feeder storage unit 18 between a retracted position, as shown in FIG. 2, and a transfer position (e.g., as shown in FIG. 5) in which the replacement feeder storage unit 18 is at a second location relatively distant (in the Y direction) with respect to the AGV 10. In the retracted position, the transport system 11 is substantially within the horizontal spatial projection of the AGV 10, allowing the AGV 10 to move safely. However, in the transfer position, the front of the replacement feeder storage unit 18 of the transport system extends beyond the horizontal spatial projection of the AGV 10, allowing the AGV 10 to be positioned adjacent to the machine receiving seat, facilitating the transfer of feeders between the receiving seat and the replacement feeder storage unit 18. In moving between the retracted and transfer positions, the engaging actuators cause the table 17 to move with the refill feeder storage unit 18 resting thereon, with a horizontal component of movement in a direction perpendicular to the front face, i.e. parallel to the Y axis, i.e. towards or away from the machine being used. This is done by pivoting the pivot legs 16 to move the storage unit 18 between the retracted and transfer positions in a path of movement that includes both vertical and horizontal components of movement. As shown, this path of movement is arched by the pivoting movement of the pivot legs 16.

[0029] 3 is a schematic perspective view of a machine-side receiving base 35 mounted on a placement machine. The receiving base 35 comprises a substantially flat horizontal base 36. In use, the base 36 supports a set-up feeder storage unit 40 (see, for example, FIG. 4) adapted to receive a plurality of feeders 15. At both ends (i.e., at the respective ends spaced apart from each other in the X-direction) of the base 36, a front machine positioning frame 37 and a rear machine positioning frame 38 are provided. The front machine positioning frame 37 comprises a front machine positioning dock 39A, while the rear machine positioning frame 38 comprises a rear machine positioning dock 39B, each of which comprises an upward opening designed to just receive the front machine-side positioning member 24A and the rear machine-side positioning member 24B, respectively.

[0030] Figures 4 to 9 are schematic perspective views of a transfer sequence for feeder replenishment using the AGV 10 and transfer system 11 of Figure 2. For clarity, some components of the transfer system 11 have been omitted from the figures.

[0031] FIG. 4 shows a schematic of the AGV 10 positioned next to the placement machine such that the storage frame 23 is approximately aligned with the receiving seat 35 (depending on the AGV's inherent positional accuracy). The transport system 11 holds the supplementary feeder storage unit 18 in a retracted position as shown during positioning of the AGV 10 relative to the placement machine. The feeder 15A is shown in a tray of the supplementary feeder storage unit 18 and held in an upright position by engaging with the feeder engagement track 19. As can be seen in FIG. 4 (omitted in FIG. 2), there is a positioning frame 44 that is attached to the supplementary feeder storage unit 18 and can move together with the supplementary feeder storage unit 18, and which supports the feeder movement unit. More specifically, the positioning frame 44 comprises a machine-side portal structure 45 and a vehicle-side portal structure 46, with a movable rail 47 supported between them. The movable rail 47 can be driven in a horizontal direction parallel to the X-axis by a drive means (not shown). For example, the machine side portal structure 45 and the vehicle side portal structure 46 may have a worm screw rotatable by a drive means to drive the movable rail 47, although other possibilities will be apparent to those skilled in the art. The movable rail 47 has a feeder movement unit suspended therefrom.

[0032] In FIG. 4, the platform 36 of the receiving seat 35 can be seen supporting the setup feeder storage unit 40. In use, the setup feeder storage unit 40 remains in the placement machine during placement operations. The setup feeder storage unit 40 is essentially similar to the refill feeder storage unit 18 in that it takes the form of a tray with side walls 41, a number of feeder engagement tracks 42 at the bottom, and a back bar 43 which contributes to the structural rigidity of the setup feeder storage unit 40. The feeder 15B is shown engaged with one of the feeder engagement tracks 42. It should be noted that in the retracted position shown in FIG. 4, the refill feeder storage unit 18 is somewhat taller (i.e. has a higher Z value) than the setup feeder storage unit 40.

[0033] When the AGV 10 is positioned proximate the placement machine as shown in Figure 4, the engagement actuators are actuated to move the supplementary feeder storage unit 18 out of its retracted position and towards the transfer position (see Figure 5). This is done by rotating the pivot legs 16 towards the placement machine. The rotation causes the table 17, and therefore the supplementary feeder storage unit 18, to move in an arched path, which causes the front and rear vehicle positioning docks 31A and 31B to lower and disengage from the front and rear vehicle positioning members 34A and 34B, respectively, and causes the supplementary feeder storage unit 18 to move horizontally (i.e. in the positive Y direction) and vertically (i.e. in the negative Z direction) towards the receiving seat 35. It should be noted that this horizontal movement is not impeded by the engagement of the front and rear vehicle positioning members 34A, 34B with the respective front and rear vehicle positioning docks 31A, 31B, because the surfaces of the respective positioning members and docks are inclined.

[0034] 5 is a schematic diagram of the transport system with the replacement feeder storage unit 18 in the transport position with the pivot legs 16 fully rotated. The front machine positioning members 24A (not visible in FIG. 5) and rear machine positioning members 24B are fully lowered and engaged with the front machine positioning dock 39A (not visible in FIG. 6) and rear machine positioning dock 39B, respectively. The replacement feeder storage unit 18 is not rigidly connected to the AGV 10 and therefore has some "play" or margin in its positioning so that the engagement between the machine positioning members and the machine positioning docks brings the replacement feeder storage unit 18 into the desired alignment to provide the correct relative positioning in both the horizontal and vertical planes between the replacement feeder storage unit 18 and the setup feeder storage unit 40 to allow the transfer of feeders between the two feeder storage units.

[0035] When the refill feeder storage unit 18 is in the transfer position, it is at the same height as the setup feeder storage unit 40, i.e., the feeder engagement tracks 19 and 42 are at the same height. The refill feeder storage unit 18 and the setup feeder storage unit 40 are also close enough in the Y direction to allow transfer of feeders from one to the other. Additionally, the table 17 is aligned in the X direction with the receiving seats 35.

[0036] From there, as shown diagrammatically in FIG. 6, the refill feeder storage unit 18 is moved along the X-axis relative to the table 17 by a linear actuator mechanism so that a particular feeder engaging track 19 with a full feeder 15B is aligned with a particular empty feeder engaging track 42 as required for the operation of the placement machine.

[0037] The feeder movement unit is then driven along the X axis until the paddle 25 is directly behind the engagement surface 48 of feeder 15B (the same position along the X axis, but a smaller Y value), as shown diagrammatically in Figure 7. As shown, engagement surface 48 is on a small protrusion protruding from the top edge of feeder 15B.

[0038] The paddle 25 then moves towards the machine, i.e. in the positive Y direction, as shown diagrammatically in Figure 8. The paddle 25 abuts the engagement surface 48, thereby pushing the feeder 15B along its feeder engagement track 19 to another empty feeder engagement track 42.

[0039] Figure 9 shows feeder 15B diagrammatically fully inserted into the set-up feeder storage unit 40. Back bars 43 act as end stops for feeder 15B, preventing it from being pushed too far into the placement machine. It should be noted that while the schematic perspective nature of Figure 9 may give the false impression that feeder 15B overhangs the refill feeder storage unit 18, this is not the case and there is no risk of collision between feeder 15B and the refill feeder storage unit 18.

[0040] In the sequence described above, a full feeder 15A is shown being transferred to the setup feeder storage unit 40. Subsequently, an empty or nearly empty feeder 15B can optionally be transferred to the refill feeder storage unit 18. This is done by aligning the refill feeder storage unit 18 with the setup feeder storage unit 40 so that the empty feeder engagement track 19 is aligned with the empty feeder 15B, and then having the feeder drive unit pull the feeder 15B into its feeder engagement track 19 with the paddle 25.

[0041] In an alternative embodiment, and depending on the particular feeder set-up, an empty or nearly empty feeder 15B may first be transferred to the empty feeder engaging track 19, after which the refill feeder storage unit 18 may be subsequently moved using a linear actuator mechanism until the full feeder 15A is aligned with the now empty feeder engaging track 42, and the full feeder 15A may be transferred thereto.

[0042] Figures 10 to 12 are schematic perspective views of a transfer sequence for a setup exchange using an AGV 10 and a transfer system 11' that has many parts in common with the transfer system 11 of Figure 2. For clarity, some parts of the transfer system 11 have been omitted from the figures.

[0043] As shown in Figure 10, transport system 11' has similar components to transport system 11, but the refill feeder storage unit 18 has been replaced with a set-up feeder storage unit 40 similar to that shown in Figure 4, having set-up feeder storage unit side walls 41 (only one is visible in Figure 10) and feeder engagement tracks 42 on table 17. For purposes of illustration, a single feeder 15 is shown positioned in an upright position in a corresponding feeder engagement track 42, although in normal use multiple, and possibly all, feeder engagement tracks 42 will each be provided with a feeder.

[0044] In Fig. 10, the AGV 10 positions itself next to the placement machine so that the storage frame 23 is roughly aligned (depending on the accuracy of the AGV's positioning) with the empty receptacle 35. The transport system 11' holds the setup feeder storage unit 40 in a retracted position as shown during positioning of the AGV 10 relative to the placement machine. In this retracted position, the rear vehicle positioning member 34B engages with the rear vehicle positioning dock 31B and the front vehicle positioning member 34A (not visible in Fig. 10) engages with the front vehicle positioning dock 31A.

[0045] In Fig. 11, the setup feeder storage unit 40 is shown moved to its transfer position by rotating the pivot legs 16 towards the placement machine, whereby the table 17, and therefore the setup feeder storage unit 40, moves along an arched path such that the front and rear vehicle positioning docks 31A and 31B are lowered and thereby disengaged from the front and rear vehicle positioning members 34A and 34B, respectively, while the front and rear machine positioning members 24A and 24B are lowered and engaged with the front and rear machine positioning docks 39A (not visible in Fig. 11) and 39B (not visible in Fig. 11), respectively. This causes the setup feeder storage unit 40 to move both horizontally (i.e. in the positive Y direction) and vertically (i.e. in the negative Z direction) towards the receiving seat 35.

[0046] Subsequently, as shown in FIG. 12, the setup feeder storage unit 40 can be transferred to the receiving seat 35. Conveniently, the transfer can be performed by a transfer device (not shown) provided on the placement machine, which operates to pull the setup feeder storage unit 40 to the receiving seat 35. Such a transfer device is obvious to those skilled in the art as an aid to setup swapping and will not be described in further detail here. Alternatively, a transfer device can be provided in the transfer system 11' to push the setup feeder storage unit 40 into the receiving seat 35. In this case, such a transfer device can be similar to the feeder movement unit already described. Indeed, in some embodiments, the feeder movement unit itself can be configured to provide such additional functionality.

[0047] The above described embodiments are merely examples, and other possibilities and alternatives within the scope of the present invention will be apparent to those skilled in the art. For example, the above described embodiments may provide an integral docking port on the placement machine. However, one advantage of the present invention is that a docking port may alternatively be retrofitted to the placement machine. In such a scenario, a frame with a docking port may be disposed adjacent to the side of the placement machine. The frame may be mounted or attached to the placement machine, for example. Alternatively, the frame may be attached to an adjacent floor surface separately from the placement machine, and then adjusted to the correct working height relative to the adjacent placement machine.

[0048] The transport system 11' may also be used for transporting individual feeders rather than the entire set-up feeder storage unit. In that case, a feeder moving unit may be provided mounted on the transport system 11', for example coupled between the front and rear upright frame members 32, 33, for selectively pushing feeders into the set-up feeder storage units located in the receiving seat 35. As yet another alternative, a feeder moving unit may be provided which is operable to simultaneously push a number of feeders, optionally all feeders, in the transport system 11' into the set-up feeder storage units in the receiving seat 35. In this way, rapid set-up changeovers can be performed without transporting the set-up feeder storage units. This can be easily achieved by providing a relatively wide paddle which can simultaneously engage all the feeders.

[0049] Although the initially described embodiment uses a pivotable arm to effect movement of the storage frame, effectors other than arms can be used as long as separate axes of motion are provided to produce Y and Z motion.

[0050] Another embodiment using an alternative form of engagement actuator is shown in a schematic perspective view from above in FIG. 13. In this embodiment, instead of using pivoting legs, the engagement actuator includes a lift mechanism for suspending the storage unit 52 (e.g., the refill feeder storage unit or the setup feeder storage unit already described) from the transport system 51 and for vertically moving the storage unit 52. Furthermore, the lift mechanism can move horizontally relative to the vehicle used. The combination of vertical and horizontal movements possible with this type of engagement actuator also allows the storage unit 52 to be moved between a retracted position in which the storage unit 52 is in a first location relatively close to the vehicle and a transport position in which the storage unit 52 is in a second location relatively far from the vehicle and in which the machine side positioning members 54A, 54B engage with machine side positioning docks (not shown) located in proximity to a receiving seat (not shown) to allow the storage unit to be positioned relative to the machine (not shown).

[0051] As shown in FIG. 13, the transport system 51 is suitable for mounting on an AGV (not shown) as in the previously described embodiments. The transport system 51 comprises a rigid frame 53 supporting a lift mechanism consisting of a gantry 55, a table 56 suspended therefrom by cables 57, and associated pulleys 58. The gantry 55 is movable horizontally (i.e., parallel to the Y-axis as shown) by a suitable horizontal actuator (not shown), e.g., a rack-and-pinion mechanism or a linear drive, such as a mating actuator, and the table 56 moves horizontally with the gantry 55. Movement of the cable 57, e.g., by winding with a rotary actuator, results in vertical movement of the suspended table 56 and the storage unit 52 supported thereon, i.e., parallel to the Z-axis in the figure. A pair of legs 59 extend from the underside of the table 56 and serve to stabilize the table 56 by resting on the platform (not shown) of the AGV when the storage unit 52 is in the retracted position. The table 56 further has a front machine side positioning member 54A and a rear machine side positioning member 54B, both of which protrude downward from the rear side of the table 56. These are used in the same manner as described in the previous embodiment in that each of them can engage with a respective machine side positioning dock (not shown) located adjacent to the receiving seat to position the storage unit 52 with respect to the machine in the transfer position. As in the previous embodiment, the machine side positioning members 54A, 54B can have one of a pair of a protrusion having at least one surface angled with respect to the vertical to form a sloping surface and a recess having at least one surface angled with respect to the vertical to form a sloping surface, so that when engaging with the respective machine side positioning dock in the transfer position, the table 56, and therefore the storage unit 52, can be guided to the correct position with respect to the machine to perform a replenishment or setup replacement operation. Although not shown in FIG. 13, a feeder movement unit similar to that described in the previous embodiment can also be provided in a form mounted on the lift mechanism to perform a replenishment or setup replacement operation.

[0052] Advantageously, the weight carried by the AGV when docking the table 56 with the machine can be monitored, such as by providing one or more sensors (not shown), such as strain gauges or torque sensors, with one or more cables 57, which can provide the control system with data representative of the strain in each cable 57 and thus the weight carried by the cable. Alternatively, the weight can be measured through monitoring the current flowing through the or each rotary actuator driving the cable 57. The or each rotary actuator can be controlled in response to the monitored signal. In this way, the weight carried by the AGV and thus the (possibly large) weight transfer from the AGV to the machine can be controlled, minimizing potentially damaging "spikes" in the transferred weight. Such smoothing of the transferred weight can be further improved by providing elastic members (not shown), such as springs, between the AGV platform and the transfer system 51 and / or along the cables 57, or alternatively, an additional active control system can be provided between the AGV platform and the transfer system 51 to control the transferred weight.

[0053] As a further enhancement, if there are a sufficient number of AGVs available, an AGV may be permanently positioned adjacent the machine and underneath table 56, thereby supporting at least some of the weight of table 56 when in use (i.e., during a placement operation), with the weight supported being controlled via the sensor system outlined above.

[0054] The weight transfer control system and methodology described above may be used in the transport system of the first embodiment as well, or indeed in other types of transport systems within the scope of the present invention.

[0055] Although the present invention has been described with reference to the specific example of transporting feeders and / or cartridges to and from a placement machine, the present invention is equally applicable to the transport of other articles associated with an SMT production line. For example, the transport system may be utilized to transport printing screens or stencils to and from a printing press, including, but not limited to, printing screens or stencils mounted on tension frames therefor.

[0056] Although the present invention has been described for use with AGVs, the transport system can also be provided for other types of vehicles, including hand trucks.

[0057] While the embodiments described above provide both horizontal and vertical components in moving the storage units between the retracted and transfer positions, in some situations vertical movement is not required. For example, if it can be ensured that the vehicle, and therefore the storage units carried by it, are at the appropriate height, then only horizontal movement need be used to move the storage units to the transfer positions. In that case, only purely horizontal engagement members need be provided on the machine and vehicle. [Explanation of symbols]

[0058] 1 AGV 2 Chassis 3 wheels 4. Platform 10 AGV 11, 11' Transfer system 12 Chassis 13. Platform 14 wheels 15, 15A, 15B Feeder 16 pivoting leg 17 Table 18 Refill Feeder Storage Unit 19 Feeder Engagement Track 20 side wall 21 Worm Screw 22 Gears 23 Storage Frame 24A Front machine side positioning member 24B Rear machine side positioning member 25 Paddle 26 Lower Rack 27 Upper Rack 28 Arm 30 Drive belt 31A Front carrier side positioning dock 31B Rear transport vehicle side positioning dock 32 Front upright frame member 33 Rear upright frame member 34A Front carrier side positioning member 34B Rear transport vehicle side positioning member 35 Receiving seat 36 units 37 Front Machine Positioning Frame 38 Rear Machine Positioning Frame 39A Front Machine Positioning Dock 39B Rear Machine Positioning Dock 40 Setup Feeder Storage Unit 41 Setup Feeder Storage Unit Side Wall 42 Feeder Engagement Track 43 Back Bar 44 Positioning frame 45 Machine side gate structure 46 Vehicle side gate structure 47 Movable Rail 48 Engagement surface 49 Bracket 51 Transport System 52 Storage Unit 53 Frames 54A Front machine side positioning member 54B Rear machine side positioning member 55 Gate structure 56 Table 57 Cable 58 Pulley 59 legs

Claims

1. 1. A transfer system for transferring articles between a transport vehicle and a receiving platform of a machine, comprising: An engagement actuator; a storage unit for storing at least one article to be used, the storage unit being movably mounted to the transport vehicle to be used and including a front surface adapted to be adjacent to the receiving seat to be used and a machine side positioning member; Equipped with A transport system in which the engagement actuator operates to move the storage unit between a retracted position in which the storage unit is at a first location relatively close to the transport vehicle and a transport position in which the storage unit is at a second location relatively remote from the transport vehicle and the machine-side positioning member can engage with a machine-side positioning dock located near the receiving seat to position the storage unit relative to the machine.

2. 2. The transfer system of claim 1, wherein the machine side positioning member comprises one of a set consisting of a protrusion having at least one surface angled relative to the vertical to form a sloping surface, and a recess having at least one surface angled relative to the vertical to form a sloping surface.

3. 2. The transport system of claim 1, further comprising a vehicle-side positioning dock attached to the vehicle in use, The storage unit includes a vehicle-side positioning member, A transport system, wherein the vehicle-side positioning member engages with the vehicle-side positioning dock in the retracted position to position the storage unit relative to the vehicle.

4. 4. The transfer system of claim 3, wherein one of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a protrusion having at least one surface angled relative to the vertical to form an inclined surface, and the other of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a recess designed to exactly receive the protrusion, and optionally, one of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a cone and the other of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a conical recess, and optionally, one of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a linear ridge and the other of the transport vehicle side positioning member and the transport vehicle side positioning dock comprises a linear recess.

5. 2. The transport system of claim 1, wherein the engagement actuator is operable to effect movement of the storage unit in a direction perpendicular to the front surface and therefore with a horizontal component of movement towards or away from a machine for use.

6. 6. The transport system of claim 5, wherein the engagement actuator is operable to effect movement of the storage unit with a vertical component of movement.

7. 7. The transport system of claim 6, wherein the engagement actuator comprises a pivoting leg that couples the storage unit to the transport vehicle, the pivoting leg being configured to move the storage unit between the retracted position and the transport position in a movement path that includes both vertical and horizontal movement components.

8. 7. The transport system of claim 6, wherein the engagement actuator includes a lift mechanism for suspending the storage unit from the transport system to move the storage unit vertically, optionally the lift mechanism includes a cable for suspension of the storage unit, and further optionally the cable is retractable for vertical movement of the suspended storage unit.

9. 9. The transport system of claim 8, wherein the lift mechanism is horizontally movable relative to the vehicle in use.

10. 2. The transport system of claim 1, wherein the storage unit comprises a feeder receptacle movable relative to the engaging actuator in a horizontal direction parallel to the front surface, the tray adapted to store at least one item for use.

11. 2. The transfer system of claim 1, wherein the storage unit is adapted to hold a tray, the tray adapted to store the at least one item, and the tray is movable relative to the storage unit in a horizontal direction perpendicular to the front surface, whereby the tray can be transferred to the receiving seat when the storage unit is in a transfer position.

12. 2. The transport system of claim 1, comprising an article moving unit having a movable paddle adapted to abut individual articles, and a paddle actuator operable to move the movable paddle in a direction perpendicular to the front surface to feed the articles towards a machine that uses the articles.

13. 13. The transport system of claim 12, wherein the movable paddle is movable relative to the storage unit in a horizontal direction parallel to the front surface so that, in use, it can abut against a selected item from among items arranged within the storage unit.

14. The transfer system of claim 1 , wherein the article comprises a feeder or a cassette and the machine comprises a placement machine.

15. The transfer system of claim 1 , wherein the article comprises a printing screen or stencil and the machine comprises a printing machine.

16. 2. The transport system of claim 1, further comprising: means for monitoring the weight borne by said vehicle and means for controlling the weight borne by said vehicle as said storage unit moves from said retracted position to said transfer position.

17. 17. An automated guided vehicle comprising a transport system according to any one of claims 1 to 16.

18. 1. A method for transferring an article from a transport vehicle to a receiving seat of a machine, comprising the steps of: i) providing a machine side positioning dock adjacent to said receiving seat; ii) providing a transport system according to any one of claims 1 to 16 on a vehicle with at least one item in said storage unit; iii) moving the vehicle proximate to the machine with the storage unit in its retracted position; iv) moving said store unit to its transfer position such that said machine side positioning member engages said machine side positioning dock; v) transferring items from said storage units to said receiving seats; A method comprising:

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