System and method for improving reliability of replacement items in stencil printing machines

Abstract

A movable trolley includes: a housing configured to move along a horizontal surface; and a plurality of shelves, each of the plurality of shelves configured to move between a retracted position, in which the shelf is located within the housing, and an extended position, in which the shelf is extended from the housing. The movable trolley further includes a sensing system configured to determine whether each of the plurality of shelves is in the retracted position and a type of item supported by the shelves. Other aspects of the movable trolley are further disclosed.

Description

Background of the Invention 1. Technical Field

[0002] The present application relates generally to stencil printers and related methods for printing viscous materials (eg, solder paste) on electronic substrates (eg, printed circuit boards (PCBs)), and more particularly to systems and methods for replacing items in a stencil printer. 2. Background technology

[0003] When manufacturing surface mounted printed circuit boards, a stencil printer may be used to print solder paste onto the circuit board. Typically, a circuit board having a pad pattern or some other conductive surface on which the solder paste is to be deposited is automatically fed into the stencil printer; and one or more small holes or marks on the circuit board (called "fiducials") are used to properly align the circuit board with the stencil or screen of the stencil printer before the solder paste is printed onto the circuit board. In some systems, an optical alignment system implemented as a vision system is used to align the circuit board with the stencil.

[0004] Once the circuit board has been properly aligned with the stencil in the printer, the circuit board is raised to the stencil, solder paste is dispensed onto the stencil, and a wiper blade (or scraper) traverses the stencil to force the solder paste through the apertures in the stencil and onto the circuit board. As the scraper moves across the stencil, the solder paste tends to roll in front of the blade, which desirably causes mixing and shearing of the solder paste to achieve the desired viscosity to facilitate filling of the apertures in the screen or stencil. Solder paste is typically dispensed onto the stencil from a standard box. The stencil is then separated from the circuit board, and adhesion between the circuit board and the solder paste leaves most of the material on the circuit board. Before printing additional circuit boards, the material left on the surface of the stencil is removed during the cleaning process.

[0005] Another process in circuit board printing includes inspecting the circuit board after solder paste has been deposited on the surface of the circuit board. Inspecting the circuit board is important to determine that a clean electrical connection can be made. Excess solder paste may cause a short circuit, while too little solder paste in the proper location may prevent electrical contact. Typically, vision inspection systems are further employed to provide two-dimensional or three-dimensional inspection of the solder paste on the circuit board.

[0006] Today's stencil printers require manual intervention to perform routine operations. For example, during changeover, the operator must perform many manual tasks, such as changing stencils, changing solder paste boxes, changing scraper blades, and changing support tools. Each of these tasks requires the operator to manually perform the task. For example, in most stencil printers, the operator must unlock the stencil, remove the stencil, correctly insert the replacement stencil, and lock the replacement stencil in place. The changeover operation may take up to 30 minutes, during which the stencil printer is not working, which may cause the PCB production line to be out of work. Summary of the invention

[0007] One aspect of the present disclosure relates to a movable trolley, the movable trolley comprising a housing configured to move along a horizontal surface and a plurality of shelves supported by the housing. Each of the plurality of shelves is configured to move between a retracted position, in which the shelf is located within the housing, and an extended position, in which the shelf is extended from the housing. The movable trolley further comprises a sensing system configured to determine whether each of the plurality of shelves is in the retracted position and the type of items supported by the shelf.

[0008] Embodiments of the movable trolley may further include configuring a sensing system for each shelf, the sensing system having at least one sensor coupled to the housing and at least one flag coupled to the housing. For each shelf, the sensing system may include: a first sensor associated with a first flag in an upper position relative to the shelf, and a second sensor associated with a second flag in a lower position relative to the shelf. When the shelf is in a retracted position within the housing of the movable trolley, the sensors may be configured to return one of the following signals: upper low (off) and lower low (off) = shelf empty; upper high (on) and lower low (off) = loading tool tray; upper low (off) and lower high (on) = unloading tool tray; and upper high (on) and lower high (on) = template. The first sensor and the second sensor may be further configured to generate a signal regarding whether an item is fully inserted into its corresponding shelf.

[0009] Another aspect of the present disclosure relates to a method for determining whether a shelf of a movable trolley is in a retracted position. In one embodiment, the method includes sensing a flag associated with the shelf to determine the position of the shelf.

[0010] Embodiments of the method may further include providing: a first sensor associated with a first flag in an upper position relative to a shelf; and a second sensor associated with a second flag in a lower position relative to the shelf. When the shelf is in a retracted position within the housing of the movable trolley, the sensors may be configured to return one of the following signals: Up Low (Off) and Down Low (Off) = Shelf Empty; Up High (On) and Down Low (Off) = Loading Tool Pallet; Up Low (Off) and Down High (On) = Unloading Tool Pallet; and Up High (On) and Down High (On) = Template. The first sensor and the second sensor may be further configured to generate a signal regarding whether an item is fully inserted into its respective shelf.

[0011] Yet another aspect of the present disclosure relates to a system for mechanically and electrically coupling a movable trolley to a stencil printer having at least one of a plurality of items for replacement within the stencil printer, the stencil printer comprising a docking station configured to receive the movable trolley, the movable trolley being configured to receive used items and / or provide new items to the stencil printer. In one embodiment, the system comprises a first interface panel associated with one of the stencil printer and the movable trolley. The first interface panel comprises a locking magnet and a metal disc array. The system further comprises a second interface panel associated with the other of the stencil printer and the movable trolley. The second interface panel comprises a metal plate and a contact array. When the movable trolley is docked to the stencil printer, the locking magnet of the first interface panel is configured to magnetically secure the metal plate of the second interface panel, and the contact array of the second interface panel is configured to engage the metal disc array of the first interface panel.

[0012] Embodiments of the system may further include: a third interface panel associated with the stencil printer and spaced apart from the first interface panel; and a fourth interface panel associated with the movable trolley and spaced apart from the second interface panel. The first interface panel may be associated with the stencil printer, and the second interface panel may be associated with the movable trolley. The metal plate may be a steel plate. The locking magnet of the first interface panel may be configured to communicate with a controller associated with the movable trolley or a controller of the stencil printer to control the operation of the locking magnet to secure the movable trolley with the stencil printer or to disengage them. The contact array may include a plurality of spring contacts. The metal disk may include a plurality of hard gold disks. The system further includes a guide assembly for guiding the movable trolley to the stencil printer when the movable trolley is docked to the stencil printer. The guide assembly may include at least one forward-facing roller fixed to the housing of the movable trolley. The at least one forward-facing roller may be configured to contact at least one guide member disposed on the face of the stencil printer. The at least one forward facing roller may include two spaced apart forward facing rollers, and the at least one guide may include two spaced apart guides. The two spaced apart forward facing rollers may be configured to contact the two spaced apart guides to guide the movable sled relative to the stencil printer.

[0013] Another aspect of the present disclosure relates to a method for mechanically and electrically coupling a movable trolley to a stencil printer having at least one of a plurality of items for replacement within the stencil printer, the stencil printer including a docking station configured to receive the movable trolley, the movable trolley being configured to receive a used item and / or provide a new item to the stencil printer. In one embodiment, the method includes: providing a first interface panel associated with one of the stencil printer and the movable trolley, the first interface panel including a locking magnet and a metal disk array; providing a second interface panel associated with the other of the stencil printer and the movable trolley, the second interface panel including a metal plate and a contact array; magnetically securing the metal plate of the second interface panel to the locking magnet of the first interface panel; and engaging the metal disk array of the first interface panel with the contact array of the second interface panel.

[0014] Embodiments of the method may further include: a third interface panel associated with the stencil printer and spaced apart from the first interface panel; and a fourth interface panel associated with the movable trolley and spaced apart from the second interface panel. The first interface panel may be associated with the stencil printer, and the second interface panel may be associated with the movable trolley. The locking magnet of the first interface panel may be configured to communicate with a controller associated with the movable trolley or a controller of the stencil printer to control the operation of the locking magnet to secure the movable trolley with the stencil printer or to disengage them. The method may further include: guiding the movement of the movable trolley to the stencil printer when the movable trolley is docked to the stencil printer. Guiding the movement of the movable trolley may include a guide assembly having at least one forward-facing roller fixed to a housing of the movable trolley. The at least one forward-facing roller may be configured to contact at least one guide disposed on a face of the stencil printer. The at least one forward-facing roller may include two spaced-apart forward-facing rollers, and the at least one guide may include two spaced-apart guides. The two spaced apart forward facing rollers may be configured to contact the two spaced apart guides to guide the movable carriage relative to the stencil printer.

[0015] Another aspect of the present disclosure relates to a system for measuring assembly materials in a cartridge of a stencil printer, the system comprising a turntable configured to support at least one cartridge. In one embodiment, the system comprises a laser height sensor coupled to a frame of the stencil printer. The laser height sensor is positioned above the at least one cartridge and configured to generate a laser beam toward the at least one cartridge to determine the height of the assembly materials within the at least one cartridge.

[0016] Another aspect of the present disclosure relates to a method of measuring assembly material in a cartridge of a stencil printer, the stencil printer including a turntable configured to support at least one cartridge. In one embodiment, the method includes: sensing the height of assembly material within at least one cartridge supported by the turntable; and if at least one cartridge is determined to be empty, providing an alert to replace at least one cartridge with a new cartridge, and if at least one cartridge is determined to have a sufficient amount of assembly material, continuing to use the at least one cartridge.

[0017] Embodiments of the method may further include sensing the height of the assembly material, such sensing being accomplished by a laser height sensor coupled to a frame of the stencil printer. The laser height sensor may be positioned above the at least one cartridge and configured to generate a laser beam directed toward the at least one cartridge to determine the height of the assembly material within the at least one cartridge. The method may further include calibrating the laser height sensor to determine a zero reference position. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in various figures is represented by the same reference numeral. For the purpose of clarity, not every component may be labeled in every figure. In the drawings:

[0019] Figure 1 It is a front perspective view of a stencil printing machine;

[0020] Figure 2 It is a front view of the stencil printing machine;

[0021] Figure 3 yes Figure 2 A plan view of the stencil printing press shown in , with some parts removed;

[0022] Figure 4 is a perspective view of a movable trolley according to an embodiment of the present disclosure;

[0023] Figure 5 and Figure 6 is an enlarged perspective view of a movable tackle with portions removed to illustrate aspects of the movable tackle, particularly a sleeve or shelf of the movable tackle in an in-situ position;

[0024] Figure 7 is an enlarged perspective view of an upper pivoting flag member and a lower pivoting flag member and a sensor of a movable trolley;

[0025] Figure 8 is a perspective view of a magnetic lock for securing a movable carriage to a stencil printing machine;

[0026] Fig. 9is a top plan view of the movable trolley and the stencil printing press prior to docking the movable trolley with the stencil printing press;

[0027] Fig.10 is an enlarged stereogram of the locking magnet;

[0028] Fig.11 is a side view of the movable trolley showing an alignment sensor and mating features of the movable trolley;

[0029] Fig.12 and Fig.13 is a view showing a spring contact;

[0030] Fig.14 is a perspective view of a first connector half having a plurality of spring contacts disposed on a stencil printer;

[0031] Fig.15 is a front view of a second connector half having a plurality of trays;

[0032] Fig.16 is a stereoscopic view of a laser sensor used to determine the height of material in a material cartridge barrel;

[0033] Fig.17 and Fig.18 is a perspective view of a stencil printer with portions removed to illustrate a laser sensor positioned to sense the height of material within a material cartridge barrel;

[0034] Fig.19 is a three-dimensional diagram of the strain gauge;

[0035] Fig. 20 is a stereogram of a flexure force sensor;

[0036] Fig.21 is a perspective view of a drive mechanism for extending and retracting a shelf of a movable trolley;

[0037] Fig. 22 Yes Fig.21 A perspective view of a shelf of a movable trolley of a drive rod of the drive mechanism shown;

[0038] Fig.23 is another perspective view of a drive mechanism having a drive rod;

[0039] Fig.24 is another perspective view of the drive mechanism showing the home position sensor; and

[0040] Fig.25 It is another stereoscopic diagram of the drive mechanism. DETAILED DESCRIPTION

[0041] The present disclosure generally relates to material application machines (referred to herein as "stencil printers," "screen printers," "printing machines," or "printers") and other equipment used in surface mount technology (SMT) production lines and configured to apply assembly materials (e.g., solder paste, conductive ink, or packaging materials) to substrates (e.g., printed circuit boards, referred to herein as "electronic substrates," "circuit boards," "boards," "PCBs," "PCB substrates," "substrates," or "PCB boards") or to perform other operations such as inspection, rework, or placement of electronic components on substrates. Specifically, embodiments of the present disclosure are described below with reference to stencil printers used to produce printed circuit boards.

[0042] For the purpose of illustration only and not to limit the generality, the present disclosure will now be described in detail with reference to the accompanying drawings. The present disclosure does not limit its application to the details of the construction and arrangement of the components set forth in the following description or shown in the accompanying drawings. The principles set forth in the present disclosure can be used in other embodiments and can be practiced or executed in various ways. Similarly, the words and terms used herein are for the purpose of description and should not be considered as limiting. Any reference to the examples, embodiments, components, elements or actions of the systems and methods cited in the singular form herein may also cover embodiments including plural numbers, and any reference to the plural form of any embodiment, component, element or action herein may also include embodiments including only the singular number. References in the singular or plural form are not intended to limit the currently disclosed systems or methods, their components, actions or elements. The use of "including", "comprising", "having", "containing", "involving" and their variants herein is intended to cover the items listed thereafter and their equivalents and additional items. References to "or" may be interpreted as inclusive, so that any item described using "or" may indicate any of a single item, multiple items, and all items in the described items. In addition, in the event of inconsistencies in the usage of terms between this document and documents incorporated herein by reference, the usage of terms in the incorporated reference documents supplements the usage of terms in this document; for contradictory inconsistencies, the usage of terms in this document shall prevail.

[0043] For purposes of illustration, embodiments of the present disclosure will now be described with reference to a stencil printer for printing assembly materials (such as solder paste) onto a circuit board. However, those skilled in the art will appreciate that embodiments of the present disclosure are not limited to stencil printers for printing solder paste onto a circuit board, but may be used for other applications requiring the dispensing of other viscous assembly materials such as glue and encapsulants. For example, the apparatus may be used to print epoxy resin for use as a bottom filler for chip level packages. Further, stencil printers according to embodiments of the present disclosure are not limited to those printers for printing assembly materials on circuit boards, but include those printers for printing other materials on a variety of substrates such as semiconductor wafers. In addition, the terms "silk screen" and "stencil" may be used interchangeably herein to describe a device in a printer that defines a pattern to be printed onto a substrate. In some embodiments, a stencil printer may include a printer supplied by ITW Electronic Assembly Equipment of Hopkinton, Massachusetts. or Edison TM A series of stencil printing machine platforms. An exemplary stencil printing machine is generally used Figure 1 In this embodiment, the stencil printer 5 is supplied by ITW Electronics Assembly Equipment Company of Hopkinton, Massachusetts. Series of stencil printing machine platforms.

[0044] refer to Figure 2 , a stencil printer of an embodiment of the present disclosure is generally indicated at 10. As shown, the stencil printer 10 includes a frame 12 that supports components of the stencil printer. The components of the stencil printer may include, in part, a controller 14, a display 16, a stencil 18, and a print head or print head assembly generally indicated at 20 that is configured to apply solder paste in a manner described in more detail below.

[0045] like Figure 2 As shown and described below, the stencil and printhead assembly may be suitably coupled or otherwise connected to the frame 12. In one embodiment, the printhead assembly 20 may be mounted on a printhead assembly gantry 22, which may be mounted on the frame 12. The printhead assembly gantry 22 enables the printhead assembly 20 to move in the y-axis direction under the control of the controller 14 and applies pressure to the printhead assembly when the printhead assembly engages the stencil 18. In one embodiment, the printhead assembly 20 may be disposed above the stencil 18 and may be lowered in the z-axis direction to contact and sealingly engage the stencil.

[0046] The stencil printer 10 may also include a conveyor system having a track (not shown) for transporting printed circuit boards (sometimes referred to herein as "printed wiring boards," "substrates," or "electronic substrates") to a printing position in the stencil printer. The track may sometimes be referred to herein as a "tractor feed mechanism" that is configured to feed, load, or otherwise deliver circuit boards to a working area of ​​the stencil printer (which may be referred to herein as a "printing nest") and unload circuit boards from the printing nest.

[0047] Additional references Figure 3 , the stencil printer 10 has a support assembly 28 for supporting a circuit board 29 (shown in phantom), which elevates and secures the circuit board so that the circuit board remains stable during the printing operation. In some embodiments, the substrate support assembly 28 may further include a specific substrate support system, such as a firm support, a plurality of pins, or a flexible tool, which is located under the circuit board when the circuit board is in the printing position. The substrate support system can be used in part to support the inner area of ​​the circuit board to prevent the circuit board from flexing or warping during the printing operation.

[0048] In one embodiment, print head assembly 20 can be configured to receive solder paste from a source (such as a dispenser, such as a solder paste box) that provides solder paste to the print head assembly during a printing operation. Other methods of supplying solder paste can be used instead of a box. For example, solder paste can be manually deposited between the blades or deposited from an external source. In addition, in one embodiment, controller 14 can be configured to use a computer with a suitable operating system (such as Microsoft Windows provided by Microsoft Corporation). The controller 14 may be a personal computer (eg, a POSIX operating system) having application specific software to control the operation of the stencil printer 10. The controller 14 may be networked with a main controller used to control a production line for manufacturing circuit boards.

[0049] In one configuration, the stencil printer 10 operates as follows. A circuit board 29 is loaded into the stencil printer 10 using a conveyor track. A support assembly 28 raises and secures the circuit board 29 in a printing position. The print head assembly 20 is then lowered in the z-axis direction until the blade of the print head assembly contacts the stencil 18 with a desired pressure. The print head assembly 20 is then moved across the stencil 18 in the y-axis direction by the print head assembly gantry 22. The print head assembly 20 deposits solder paste onto the circuit board 29 through the aperture in the stencil 18. Once the print head assembly has completely traversed the aperture of the stencil 18, the print head assembly is lifted off the stencil and the circuit board 29 is lowered back onto the conveyor track. The circuit board 29 is released from the stencil printer 10 and conveyed away so that a second circuit board can be loaded into the stencil printer. To print on the second circuit board 29, the print head assembly is lowered in the z-axis direction to contact the stencil and moved across the stencil 18 in the opposite direction to that used for the first circuit board.

[0050] An imaging system 30 may be provided for the purpose of aligning the stencil 18 with the circuit board 29 before printing and inspecting the circuit board after printing. In one embodiment, the imaging system 30 may be provided between the stencil 18 and the support assembly 28 on which the circuit board is supported. The imaging system 30 is coupled to an imaging gantry 32 to move the imaging system. In one embodiment, the imaging gantry 32 may be coupled to the frame 12 and include a beam extending between the side rails of the frame 12 to provide the imaging system 30 to move back and forth above the circuit board 29 in the y-axis direction. The imaging gantry 32 may further include a carriage device that accommodates the imaging system 30 and is configured to move in the x-axis direction along the length of the beam. The construction of the imaging gantry 32 for moving the imaging system 30 is well known in the field of solder paste printing. This arrangement allows the imaging system 30 to be located at any position below the stencil 18 and above the circuit board 29 to capture images of predefined areas of the circuit board or stencil, respectively.

[0051] After applying solder paste to the circuit board one or more times, excess solder paste may accumulate at the bottom of the stencil 18, and a stencil wiper assembly (generally indicated at 34) may be moved under the stencil to remove the excess solder paste. In other embodiments, the stencil 18 may be moved over the stencil wiper assembly.

[0052] As described above, stencil printers traditionally require manual intervention to perform replacement and / or replenishment operations of certain parts. For example, a typical stencil needs to be replaced after a certain period of time (e.g., four hours). Moreover, the stencil needs to be replaced for different production runs. In addition, the solder paste box that supplies temperature-controlled solder paste to the stencil printer needs to be replaced over time (e.g., within four hours or less). Different production runs may require different types of solder paste materials. Another item that needs to be replaced regularly is the scraper blade that is subject to wear during use. And finally, the tool used to support the substrate in the printing position is replaced when changing from one production product to another.

[0053] Embodiments of the present disclosure relate to a delivery system that is configured to automate the conversion process of a stencil printer or any other type of assembly processing equipment (including but not limited to dispensers, pick and place machines, wave soldering machines and selective soldering machines, reflow ovens, cleaning machines, and inspection machines). In one embodiment, the delivery system includes a movable trolley that is configured to engage the stencil printer to supply and receive replacement and supplementary parts and materials to the stencil printer for conversion. For example, the stencil printer may include a docking station configured to receive the movable trolley. The docking station may include an interface that enables the movable trolley to communicate with the stencil printer. A single movable trolley may be configured to include a conversion stencil, a replacement stencil, a replacement solder paste box, a supplementary solder paste box, a replacement scraper blade, a supplementary scraper blade, and a replacement support tool. During conversion, for example, the stencil printer must be reconfigured to produce different items. Therefore, for example, different types of solder paste can be used in the stencil printer to produce different products.

[0054] It should be appreciated that the concepts described herein are not limited to replacing items within a stencil printing machine, but are also applicable to the other types of equipment described above.

[0055] The conversion process described herein can be realized by a single removable pulley configured to replace and / or replenish each article. In other embodiments, more than one removable pulley can be provided. For example, the removable pulley can be configured to support a predetermined number of stencils, scraper blades, tools and paste boxes, which are selected for the production rounds expected for a specific day or a specific time period. The removable pulley and / or the stencil printing machine can be configured to identify the articles to be replaced, transport the articles to the stencil printing machine and transport the articles away from the stencil printing machine, check the articles, and interface with the stencil printing machine. The removable pulley can also be configured to remove used articles from the stencil printing machine. In addition, the removable pulley can be configured to store articles for a long time.

[0056] For paste boxes, the movable pulley and / or stencil printer can be configured to identify paste boxes, store paste boxes in a suitable environment, transport paste boxes to and from stencil printers and dispensers, check paste boxes, and interface with the stencil printer. The movable pulley can also be configured to remove used parts, such as paste boxes, from stencil printers and dispensers. In addition, the movable pulley can be configured to store paste boxes for a long time. In one embodiment, the long-term storage of solder paste can be achieved by refrigeration at 0°C to 10°C (32°F to 50°F). The paste box can be stored in a position in the movable pulley to maintain this temperature range. In another embodiment, the movable pulley can be configured to preheat the paste box before use to prepare the box for use in the stencil printer.

[0057] refer to Figure 4 In one embodiment, a movable trolley, generally indicated at 100, includes a frame or housing 102 configured to support replacement and / or replenishment items. As shown, the housing 102 of the movable trolley 100 is generally rectangular and supported on wheels or casters, each indicated at 104. In one embodiment, the movable trolley 100 is configured to be manually moved by an operator by pushing the housing 102 of the movable trolley. In this embodiment, the movable trolley 100 may be configured with a push rod or handle 106. In another embodiment, the movable trolley 100 is configured to be automatically moved by remote control or by an automated control device associated with the movable trolley, the stencil printer 10, the production line, and / or some other dedicated control device. In this embodiment, the movable trolley 100 may include wheels driven by a suitable motor and drive train and a control device associated with the movable trolley. Alternatively, in other embodiments, the control device may be associated with the stencil printer 10, the production line, and / or may be some other dedicated control device configured to control the movable trolley. The movable trolley 100 may also include one or more sensors and / or vision systems (e.g., cameras) to guide the movable trolley from, for example, a warehouse to the stencil printer 10.

[0058] In one embodiment, the movable trolley includes one or more shelves, each indicated at 110, which are configured to store items of the stencil printer 10. For example, the shelves 110 can be specifically designed to support stencils (e.g., stencil 18) and / or tool trays, each indicated at 112. As shown, the movable trolley 100 supports a single stencil 18 on one shelf 110 and supports two tool trays 112 on two shelves 110 above the shelf 110 for supporting the stencil. The shelves 110 can be configured to move vertically within the housing to reach a height suitable for operation with the stencil printer 10. In one embodiment, the shelves 110 are disposed within a carriage that is designed to move up and down within the housing 102 of the movable trolley 100. Further, the shelves 110 can be configured to extend and retract within the housing 102 of the movable trolley 100. Specifically, each shelf 110 may be configured to extend from the housing 102 to deliver a stencil 18 or a tool tray 112 to a stencil printer, to transfer items to a stencil printer, or to receive items from a stencil printer, as the case may be. Figure 4 The shelf 110 is shown extending the stencil 18 and the tool tray 112. Once extended, the shelf 112 is configured to be retracted into the housing 102 of the movable trolley 100.

[0059] In some embodiments, some of the racks 110 may be designated as "clean racks" to support clean or new items that are ready for use within the stencil printer 10. Some of the racks 110 may be designated as "dirty racks" to support used items that are to be removed from the stencil printer 10. The racks 110 may be spaced apart from each other at specific distances to receive various items. For example, the racks 110 may be spaced apart from each other by 3 / 8 inch to 1 / 8 inch. 1 / 2 inch to accommodate the stencil frame thickness.

[0060] Figure 4 The movable trolley 100 shown in FIG. 1 is fully loaded for automatically transferring articles to and from a stencil printing machine. Specifically, as described above, the movable trolley 100 includes a new stencil 18 and two tool trays 112, one tray is loaded with articles, including scraper blades and tools, and one tray is empty for receiving used articles from the stencil printing machine.

[0061] The movable trolley 100 can be configured with an interface designed to dock in a docking station provided on the stencil printer 10, whether through a mechanical interface or an electronic communication interface. In a particular embodiment, the movable trolley 100 can be configured with a unique mechanical interface that cooperates with a unique mechanical docking station of the stencil printer 10. The unique mechanical interface / docking station can include numerous geometric features. In another embodiment, the movable trolley 100 can be configured with a pin that is received in a guide associated with the stencil printer 10 to align the movable trolley with the stencil printer before fully docking the movable trolley. Other types of guides can be used, such as electrical / magnetic guides, visual guides, sensors, latches, etc. When docked in the docking station of the stencil printer 10, the movable trolley 100 can physically engage the stencil printer or be spaced apart from the stencil printer.

[0062] like Figure 4 As shown, the movable pulley 100 includes two spaced roller assemblies, each indicated at 116, which are designed to interact with features associated with a stencil printer (e.g., stencil printer 10) to guide the movable pulley to a docking position. Each roller assembly 116 includes an arm extending from a housing 102 of the movable pulley and a roller coupled to the arm at the end of the arm. The roller assembly 116 is positioned to engage with features formed in the stencil printer when the movable pulley 100 is docked on the stencil printer. Further, the movable pulley 100 includes two interface panels, each indicated at 118, which provide mechanical connection and electrical communication between the movable pulley 100 and the stencil printer. The details of the interface panel 118 will be described in more detail below.

[0063] refer to Figure 5 and Figure 6 As described above, the movable trolley 100 includes shelves 110 that are fully retracted in the housing 102 of the movable trolley in the home position. The manner in which the shelves operate to extend and retract in the housing 102 of the movable trolley will be described below with reference to Figure 21 to Figure 25 Give a description.

[0064] A sensor system is provided to determine the location and type of items contained by each shelf 110. Specifically, each shelf 110 is sized and shaped to support generally flat items, such as a stencil 18 or a tool tray 112. The sensor system is designed to inform an operator of the type of item contained within the shelf 110 (e.g., a stencil 18 or a tool tray 112) and whether the item is fully received within the shelf (in what may be referred to as a home position). For each shelf, the sensor system includes two sensors, an upper sensor 120A and a lower sensor 120B, and two pivoting flags, an upper pivoting flag 122A and a lower pivoting flag 122B, which can be configured to indicate when each shelf 110 is in a home position or a fully retracted position. Also refer to Figure 7 , the contents of each of the four trolley shelves 110 must be known and verified before and during transfer to or from the stencil printer. In one embodiment, two optical sensors 120A, 120B and two pivoting flags 122A, 122B are mounted in the housing 102 of the movable trolley 100. For each shelf, a first sensor 120A is associated with a first flag 122A and is positioned in an upper position relative to the shelf, while a second sensor 120B is associated with a second flag 122B and is positioned in a lower position relative to the shelf. In the illustrated embodiment, there are four shelves, with a first (upper) shelf being shown empty, a second shelf positioned below the first shelf being shown with loaded tool trays, a third shelf positioned below the second shelf being shown with unloaded tool trays, and a fourth (lower) shelf being shown with stencils. When the shelf 110 is in the home position, each type of item, such as a stencil 18 or a tool tray 112 (loaded and unloaded), will engage the pivoting flags 122A and / or 122B in a different manner due to its geometry. Thus, when the shelf 110 is in the home position within the housing 102 of the movable trolley 100, the sensor 120 will return one of the following signals:

[0065] Upper low (off) and lower low (off) = shelf empty;

[0066] Up high (open) and down low (closed) = loading tool tray;

[0067] Up low (off) and down high (on) = unload tool tray; and

[0068] Upper High (Open) and Lower High (Open) = Template.

[0069] This approach can also be used to ensure that the operator inserts the stencil 18 and / or tool tray 112 correctly into the rack 110 and that it does not protrude so far that it may interfere with the stencil printer during transport.

[0070] The roller assembly 116 can be used to perform a pre-alignment and easy-to-use method to dock the movable trolley 100 to the stencil printer. Specifically, once the movable trolley is docked with the stencil printer, the roller assembly 116 ensures that the movable trolley 100 will not move unintentionally in the x-axis, y-axis and z-axis directions.

[0071] As described herein, the movable trolley 100 is used to deliver new supplies to the stencil printer and is coupled or connected to the stencil printer to transfer items from the movable trolley to the stencil printer. When the movable trolley 100 is pre-positioned to engage the stencil printer, the movable trolley is pre-aligned with the stencil printer to facilitate electrical and electronic communication between the movable trolley and the stencil printer.

[0072] refer to Fig. 9 In one embodiment, the movable trolley 100 has two forward-facing rollers 116, one of which is located on the lower left side of the movable trolley housing 102 and the other is located on the lower right side of the movable trolley housing. The roller assemblies 116 are positioned to contact guides (each indicated as 130) on the surface of the stencil printer 10 to pre-align the movable trolley 100 in the x-axis direction.

[0073] Then, the movable trolley 100 is pushed further forward until one of the steel plates 134, each indicated at 134, is located on the interface panel 118 located on the lower left side of the movable trolley, and the other steel plate 134 is located on the interface panel 118 located on the lower right side of the movable trolley, as shown in FIG. Figure 4 Each steel plate 134 contacts the magnetic field generated by a corresponding locking magnet 136 of the stencil printer, as shown. Figure 8 As shown. In one embodiment, the locking magnet 136 provided on the stencil printer is an E300 type electromagnet manufactured by Security Door Controls. The locking magnet 136 eliminates the need for a key and expands the range of the access control system. The locking magnet 136 is compact and provides a higher level of security than other types of locking devices. The locking magnet 136 is configured to communicate with a controller associated with the movable trolley 100 or a controller of the stencil printer 10 (e.g., controller 14) to control the operation of the electromagnet of the locking magnet to secure or detach the movable trolley from the stencil printer 10. A display (e.g., display 16 associated with the stencil printer 10) may be provided to show the state of the locking magnet 136 relative to the movable trolley 100 in a locked or unlocked state.

[0074] Each locking magnet 136 is in an "on" state and is ready to asynchronously dock the movable trolley 100 with the stencil printer to maximize the efficiency of the stencil printer and eliminate the impact of cycle time. Once the movable trolley 100 is fully engaged to the locking magnet 136, the software associated with the controller of the stencil printer is notified by the safety sensors on the left and right sides of the movable trolley to ensure full engagement of the movable trolley before power and communication are applied to the movable trolley. One of the advantages of this structure is that the locking magnet 136 generates a strong magnetic force to hold the movable trolley 100 in place relative to the stencil printer and prevents the movable trolley from moving in the x-axis, y-axis, and z-axis directions once engaged because each electromagnet of the locking magnet has a pull force of approximately 600 pounds (lb) and excellent shear resistance. This type of latching magnet 136 also has a unique flux path that, for safety reasons, allows full magnetic force to be generated only when it is within 0.010 inches of engagement with the steel plate 135.

[0075] Fig. 9 The movable carriage 100 is shown approaching the stencil printer 10 with the roller assemblies 116 of the movable carriage aligned with corresponding guides 130 of the stencil printer. Fig.10 The interface panel 118 on the stencil printer 10 is shown having locking magnets 136 . Fig.11 An alignment sensor 138 and steel plate 134 on the movable trolley 100 are shown.

[0076] When the movable trolley 100 is ready to be replenished (or removed from the stencil printer 10), power is removed from the movable trolley and the locking magnets 136 associated with the stencil printer are de-energized, which allows the operator to roll the movable trolley away from the stencil printer. Once the left and right alignment sensors 138 indicate to the software of the controller 14 of the stencil printer 10 that the movable trolley 100 has been removed from the stencil printer, the locking magnets 136 are energized again in preparation for the next docking cycle.

[0077] The connection method between the movable carriage 100 and the stencil printer 10 includes two mating connector halves, one connector half having an array of contacts that are spring loaded to help cope with misalignment, and the other connector half having a complementary array of hard gold pads, specifically gold reinforced with nickel for durability, to complete the circuit between the movable carriage and the stencil printer.

[0078] The first connector half includes an array of spring contacts. Fig.14 A first connector half 144 is shown having an array of spring contacts 146. The exemplary spring contacts 146 are Fig.12 and Fig.13101247. The first connector halves 144 are mounted to the stencil printer 10 and assembled into an array that will help to accommodate slight misalignments of the movable trolley 100 due to imperfections in the manufacturing facility that are beyond the control of the manufacturer of the movable trolley. Facility imperfections include uneven floors, or floors that are not strong enough and floor materials that are prone to denting.

[0079] The second connector half with the hard gold plate is mounted to the movable carriage 100 as part of the interface panel 118 and is rigidly mounted. This ensures a smooth flat interface for the spring loaded contacts 146 described above. Fig.15 A second connector half 150 is shown having an array of hard gold pads, each indicated at 152. The array of hard gold pads 152 of the second connector half 150 mates with the array of spring contacts of the first connector half.

[0080] When the two connector halves 144, 150 are mated (i.e., when the movable carriage 100 is docked to the stencil printer 10), the two connector halves are initially aligned by setting the stencil printer adjustment height according to the SEMA industry standard, and then the movable carriage is mated with the stencil printer. Once mated, an additional step is performed to adjust the final height of the first connector half 144 (i.e., the spring contact side) so that the spring contact 146 is centered on the mating hard gold disk 152 of the second connector half 150 on the movable carriage 100, with a tolerance of approximately 1 millimeter (mm). This ensures that any subsequent movable carriage mated with the stencil printer 10 will mate correctly and ensures proper connection of all signals passing between the stencil printer and the movable carriage.

[0081] With this arrangement, the two connector halves 144, 150 are arranged to provide a maximum misalignment of ±4 mm in the x-axis direction, ±2 mm in the y-axis direction, and ±4 mm in the z-axis direction. This also equates to ±2 degrees of roll pitch and yaw flexibility.

[0082] Another aspect of the present disclosure relates to a method of measuring material in a cartridge for a carousel dispenser. A material cartridge introduced into a stencil printer has a finite amount of material in the cartridge. As the material is used within the stencil printer, it is sometimes necessary to return the cartridge to a material carousel that is not completely empty. This creates a problem in that the operator cannot accurately know when to transfer additional material cartridges to the carousel or the Manufacturing Execution System (MES) cannot track the material used during production. Reference Fig.16, the assembly is capable of determining a method that utilizes a laser height sensor (generally indicated at 160) to sense the plunger seal within any material cartridge barrel to accurately measure the remaining contents within the material cartridge barrel. As shown, the laser height sensor is configured to generate a laser beam 162.

[0083] refer to Fig.17 , the stencil printer 10 is configured with a turntable 170 that is configured to store and deliver paste cartridges (such as paste cartridges or tubes 172) to the print head assembly 20 of the stencil printer. The laser height sensor 160 is calibrated after being strategically positioned above the turntable 170 and facing downward to sense a zero reference position. In one embodiment, the laser height sensor 160 is manufactured by Banner Engineering Corporation and has a part number of #Q4XTKLAF600-Q8. The electrical output of the laser height sensor 160 is then read by the controller 14 of the stencil printer 10 to store a zero reference position.

[0084] refer to Fig.18 When the material cartridge 172 is placed in one of the material slots provided in the turntable 170, the turntable will rotate the material cartridge to the pick-up position. Once in the pick-up position, the electrical output of the laser height sensor 160 is read by the controller 14 of the stencil printer 10 to record the electrical output and compare it to the zero reference position to determine the contents of the material cartridge 172.

[0085] If the contents of the material cartridge 172 are determined to be empty, information is sent through the equipment MES system so that an operator can swap cartridges 172, and an external indicator flashes, alerting any local operators that the material is ready to be replaced. The external indicator can be part of the display 16 of the stencil printer 10. If the material cartridge 172 is determined to have enough material for production, the controller 14 uses this information to determine how many PCBs can be processed before the material cartridge becomes empty to return to the carousel empty slot position.

[0086] An alternative method of determining the remaining contents of the material cartridge 172 may be performed by measuring the weight of the cartridge. Fig.19 , a strain gauge 180 may be used to convert the force into an electrical output that is read by the controller 14 of the stencil printer 10 to determine the weight of the material cartridge 172 within the slot of the turntable 170. An example of the type of force gauge that may be used is a linear strain gauge. In one embodiment, the strain gauge 180 may be manufactured by Vishay Precision Group, model #MMF403994. Reference Fig. 20, a flexure force sensor 182 may be used instead of the strain gauge 180. In this embodiment, the flexure force sensor 182 may be manufactured by Tekscan, model #A101.

[0087] refer to Fig.21 and Fig. 22 The movable trolley 100 includes a drive mechanism, generally indicated at 200, configured to laterally move each shelf 110 so that the shelf can be extended into and withdrawn from the stencil printer 10. The drive mechanism 200 includes a motor-driven lead screw 202 to extend each shelf 110 of the movable trolley 100 into and withdrawn from the stencil printer 10. When the movable trolley 100 is raised to the appropriate height, a drive button 204 ( Fig.21 ) engages the drive rod 206 ( Fig. 22 ), which is attached to the side of each shelf 110. When the lead screw 202 rotates, the drive button 204 provided on each side of the shelf pushes the drive rod 206 and the shelf 110 out of the movable trolley 100, or pulls the drive rod and the shelf into the movable trolley, depending on the direction of rotation of the lead screw.

[0088] Additional references Fig.23 , the drive mechanism 200 includes a bracket 208 located on each side of the shelf 110, to which the drive button 204 is fixed. The bracket 208 is fixed to the linear bearing 210 and the lead screw 202 so that when the lead screw rotates, the bracket moves laterally. The drive rod 206 is connected to the bracket 208 to enable the drive rod and the shelf 110 to move.

[0089] refer to Fig.24 , a home sensor 212 is provided to determine whether the drive rod 206 and shelf 110 are in the home (retracted) position.

[0090] refer to Fig.25 For the shelf 110 configured to support a stencil (e.g., stencil 18), a spring-loaded plunger 214 is provided to ensure that the stencil is in a proper position when it is returned to the stencil printer 10. Further, a plunger sensor 216 is provided to determine whether the stencil is always positioned at the back of the shelf 110 so that when the stencil is returned from the stencil printer 10 to the movable trolley 100, the stencil printer side stops pushing the stencil. As the name implies, the plunger sensor 216 monitors the spring-loaded plunger 214.

[0091] In one embodiment, the movable trolley may be configured with one or more devices for transporting items from the movable trolley to the stencil printer and from the stencil printer to the movable trolley. For example, the device may include a gripper for engaging an item such as a substrate tool tray to move the tool tray from the stencil printer to a tray of the movable trolley and to move a different tool tray from the movable trolley to the stencil printer.

[0092] In one embodiment, the movable trolley comprises wheels driven by a suitable motor and transmission system and a control device configured to control the movement of the movable trolley. The movable trolley further comprises a power source (e.g., a battery) to power the movement of the movable trolley via the motor and transmission system.

[0093] In some embodiments, the movable pulley includes a controller adapted to control the operation of the movable pulley based on operating parameters obtained by the controller. The controller can be configured to communicate with a controller of a stencil printing machine and / or a controller associated with a production line. In an embodiment with multiple movable pulleys, the controller can be implemented as multiple controllers arranged in each movable pulley, and the multiple controllers communicate with each other through a controller area network (CAN) bus or other types of networks. In other embodiments, a master controller can be provided to control the operation of the controller of the movable pulley. Each movable pulley can be provided with a display operably connected to the controller. The display is adapted to display the operating parameters of the movable pulley, such as but not limited to the number of full and exhausted / used paste boxes. A suitable monitor can be provided to obtain such information. As an alternative or in addition to the aforementioned embodiments, the operating parameters can be displayed on a display arranged in the stencil printing machine and / or a display associated with the production line.

[0094] In other embodiments, the controller may be a controller dedicated to one or more movable trolleys.

[0095] In some embodiments, the material identification for the items on the movable trolley can include a device for manipulating the items and a scanner for scanning and identifying the items. For example, for the paste box, the movable trolley can be configured to include a pinch wheel to rotate the paste box to align the code or predetermined identification mark set on the paste box with the scanner set on the movable trolley. The system is configured to link the material identification associated with the paste box with the formula, production time, etc. for the stencil printing machine. In one embodiment, a barcode for identifying the items can be implemented. For example, the barcode can include a 1D scanner for UPC code, a 2D scanner for QRC code, a printed mark applied to the item, or a laser etching mark etched on the item. In another embodiment, an RFID system for identifying the items can be implemented. For example, the RFID system can include an RFID tag applied to the item and an RFID reader associated with the movable trolley. In the RFID system, a direct line of sight path between the reader and the item is not required. In addition, scanning is not required to identify all items in the movable trolley. In another embodiment, an imaging or visual system for identifying the items can be implemented. The vision system may be an imaging system similar to that associated with a stencil printer or dispenser, or on a movable cart.

[0096] In some embodiments, a database is provided to keep track of items stored on the movable trolley. In one embodiment, the database may include an open application (App) architecture and be configured to push data to the stencil printer. The movable trolley may be configured to communicate with the stencil printer to push / transmit data to the stencil printer and / or the production line, or be configured to communicate directly with the production line. The database may include job information or material information. The database may also communicate with a manufacturing execution system (MES) associated with the production line, the stencil printer, or both. The MES system may be configured to know which materials are needed for a certain production run. The movable trolley may be configured to communicate with the MES system to adjust the delivery of items to the stencil printer.

[0097] The database may be further configured to retrieve information about the item based on an identification (e.g., a barcode number). In one embodiment, a central management system may be provided wherein the stencil printer and / or the movable trolley is programmed to accept material from the movable trolley. The movable trolley is programmed to update the database to identify the material on the movable trolley, load information from the network into a database associated with the movable trolley and / or the stencil printer, and the database is tied to the MES system.

[0098] The database may be further configured to store additional information, such as usage and consumption. The database may be configured to store information locally or remotely, and may be configured to store data associated with one or more production runs. For example, the database may be configured to obtain and store data including, but not limited to, traceability of stencils, paste boxes, doctor blades, and tools, paste usage, cycles, etc.

[0099] The database may be configured to share predictive data when replacement / replenishment is required. For example, with respect to storing information related to paste cartridges, the database may be configured to perform one or more of the following: store information about when the paste cartridge needs to be refilled; perform specific functions in the event of a low paste cartridge; trigger an alarm and / or report of a low paste cartridge; signal an inventory control system associated with a stencil printer and / or production line; perform analysis of consumable usage based on operating parameters and actual usage and upstream / downstream equipment activity; predict replacement or maintenance (for the stencil printer and / or for the movable trolley); and correlate across multiple sites to predict when to swap out the paste cartridge. The database may be configured to share predictive data for other changeable / consumable items such as stencils, paste cartridges, doctor blades, and tools.

[0100] The database may be configured to store data associated with batch traceability. Additionally, an RFID or mechanical key to the stencil frame of the plate or stencil is provided to ensure proper alignment / orientation / direction / front-to-back / up-and-down when these items are inserted into the stencil printer. This information may be used to verify proper orientation and / or assembly prior to delivery of the item from a warehouse and / or prior to installation of the item in the stencil printer. A low cost reader may perform this function.

[0101] In one embodiment, the remote control device may be configured to communicate with a database via a cloud or ISP to provide the above functionality. In another embodiment, the database may be part of a computer control system of a stencil printing machine or a movable trolley or production line.

[0102] In some embodiments, the movable pulley can be configured to store materials. The movable pulley can be configured to flexibly adapt to the location where the material comes from and goes to. In addition, the movable pulley can be configured to identify the location where a specific material is located on the movable pulley. In certain embodiments, whether by automatic delivery or by manual delivery, the location is remote, local, on the movable pulley and / or on the stencil printing machine. As described above, the movable pulley can be configured to control environmental parameters. For example, the movable pulley can be configured to control the temperature of the paste contained in the paste box by cooling the stored paste box, heating the ready-to-use paste box, and cooling the paste box that has been used but still contains paste. In one embodiment, the housing can be insulated, and a cooling / heating unit can be provided to cool or heat the interior of the housing and thus cool or heat the paste box. The movable pulley can be further configured to predict when to start heating / cooling the paste box based on the upcoming production, track the time of the shelf life, and control each paste box individually to the appropriate temperature at the right time. In other embodiments, the movable pulley can include a paste box pusher to move the paste box. The movable pulley can be further configured to control humidity to avoid condensation. The mobile sled may further be configured to operate in a clean environment, such as a Standard Mechanical Interface (SMIF) environment.

[0103] In some embodiments, the mobile trolley can be configured to perform inventory control. Specifically, the mobile trolley can be configured to identify where the material is located, how much material is used, how the material is used, when the material is used, bind the material and information about the material to a customer inventory control system, and track the type of material consumed for each board or batch of boards.

[0104] In some embodiments, the movable pulley can be configured to sort the items stored on the movable pulley. As previously described, in one embodiment, a movable pulley can be provided to store, transport and deliver multiple resources, including but not limited to paste boxes. In another embodiment, the movable pulley can be configured to store, transport and deliver a single resource or item to a stencil printer. The movable pulley can be configured to serve multiple production lines. In another embodiment, the movable pulley can be configured to serve a stencil printer.

[0105] In some embodiments, the movable pulley can be configured to transport items from the movable pulley to the stencil printer and from the stencil printer to the movable pulley, and the height difference between the movable pulley and the stencil printer can be taken into account. The transportation can be automated or manual. In one embodiment, the movable pulley can be moved or remotely controlled by an automatic guided vehicle (AVG) technology associated with the movable pulley. In another embodiment, the movable pulley can be configured to move autonomously. In another embodiment, the movable pulley can be configured to move manually. In yet another embodiment, the movable pulley can be configured to automatically and / or manually move items stored on the movable pulley. For example, the movable pulley can be configured to automatically move items, and an interruption of a pre-planned activity in which items are manually moved can be provided.

[0106] In some embodiments, the time associated with performing the transport function of the movable pulley can be programmed to take into account shift changes (e.g., personnel rotation), planned maintenance, on-demand activities (e.g., recipe changes), and predicted events (just-in-time replacement). The time can be programmed to meet multiple assembly line balancing control requirements with one or more movable pulleys, as well as meet real-time on-demand material supply needs on the production line.

[0107] In some embodiments, the movable trolley is configured to perform inspections. For example, the movable trolley can inspect items on and off the trolley, including stencils, paste boxes, scraper blades, and tools. In one embodiment, a vision system associated with the movable trolley can be configured to obtain images of the items. The vision system combined with the controller can be configured to check for cleanliness, damage, wear, and identification reliability, for example, a bar code label is worn, dirty, or torn. The vision system can be implemented as any type of 2D, 3D, or color camera.

[0108] In some embodiments, the movable trolley is configured to interface with the stencil printer from both a mechanical interface and an electronic communication interface. In one embodiment, the movable trolley can be configured with a unique mechanical interface that mates with the unique mechanical interface of the stencil printer. The unique mechanical interface can be a geometric feature. In another embodiment, the movable trolley can be configured with pins that are received in guides associated with the stencil printer to align the movable trolley with the stencil printer before fully docking the movable trolley. The pins and guides can be arranged oppositely, wherein the pins are arranged on the stencil printer and the guides are arranged in the movable trolley. Other types of guides can be used, such as electric / magnetic guides, visual guides, sensors, latches, etc.

[0109] In some embodiments, the interface and docking station may be configured with a clamping system to hold the movable trolley in position relative to the stencil printer. For example, a magnetic clamping system may be employed.

[0110] In some embodiments, the stencil printer can be configured with a plurality of docking stations, for example, five docking stations. The docking station can be arranged at the front of the stencil printer or at the rear of the stencil printer.

[0111] The movable trolley and / or the stencil printer may be configured to verify whether the movable trolley can be docked and interfaced with the stencil printer. In one embodiment, a verification may be provided to confirm that the movable trolley is in position and ready to interface with the stencil printer. This verification process may further determine whether the correct material is on the movable trolley and whether the movable trolley material information can be received from the MES system or identified locally. If not, the movable trolley may be configured to activate an alarm and / or alert the operator if the wrong or damaged material is on the movable trolley.

[0112] In some embodiments, the movable trolley may be configured with an actuating device or actuator to move items onto and off the movable trolley once the movable trolley is docked to the stencil printer. Embodiments of the actuator may be implemented on the movable trolley, the stencil printer, or both. In another embodiment, the items may be manually loaded and unloaded from the movable trolley.

[0113] In some embodiments, the movable trolley can be configured to interface with the production line. Through this embodiment, the operator of the production line can confirm the correct position and confirm that the movable trolley is received on the stencil printing machine.

[0114] In some embodiments, the mobile trolley can be configured to communicate with a stencil printer, a production line, and / or select machines within a production line via an open platform. The communication system can include a wired system, a wireless system (via a public network, mesh, Bluetooth, Wi-Fi, Zigbee, WAN, node, Li-Fi, etc.), a combination of wired and wireless systems, and an infrared (IR) system.

[0115] In some embodiments, the movable trolley can be configured with a dedicated power supply. In one embodiment, the movable trolley includes a battery configured to power automated components disposed in the movable trolley, such as a mechanism for moving a stencil in and out of the movable trolley, a mechanism for moving a paste box in and out of the movable trolley, a mechanism for moving a scraper blade in and out of the movable trolley, and a mechanism for moving a tool in and out of the movable trolley. In other embodiments, the movable trolley can be configured with an uninterruptible power supply. The power supply can be configured to support actuation when "docking" (a high voltage from the stencil printer when docking, otherwise a low voltage when not docked). The power supply can be configured to recharge for autonomous operation, for example, recharging the battery with power provided by the stencil printer.

[0116] In some embodiments, the movable trolley can be configured to work with the stencil printer. For example, the movable trolley can be configured to provide a handshake function with the stencil printer before delivering an item, such as "please give me paste box #1234". The movable trolley and the stencil printer can be configured with a communication protocol and / or a library index about what is available for consumption. The movable trolley can be configured to determine whether the movable trolley has the correct item. The handshake function can be configured to ensure the correct delivery of the item, such as "this is paste box #1234", and / or the subsequent delivery of the item, such as "I have paste box #1234 now". In one embodiment, the mobile device can be configured to scan and identify the items in the movable trolley, and determine, for example, whether the item is ready for use, whether it needs to be cleaned, etc.

[0117] In some embodiments, the movable trolley can be configured to account for errors associated with handling and retrieving items in the movable trolley. For example, the movable trolley can be configured to detect incomplete movement of a party, incomplete transfer of an item (e.g., a stuck or jammed item), dropped transfers (e.g., "I passed you paste box #1234, did you receive it?"), and human intervention or hand control (e.g., "Here, let me help you"). In one embodiment, a controller associated with the movable trolley can be configured to perform static discharge control, data recovery, and / or security.

[0118] In some embodiments, the mobile trolley may be configured with a higher level of capability. In addition to guiding all equipment to the correct height, the mobile trolley will need to pull in / out all equipment for the machine gantry for attachment.

[0119] In some embodiments, the existing machine gantry, tracks, and print head of a stencil printer may be configured to shuttle articles in and out.

[0120] In some embodiments, the movable carriage may be configured with a paste box indexer to load / unload paste boxes.

[0121] In some embodiments, the mobile cart may be configured to communicate with the stencil printer, the production line, and a warehouse associated with the production line.

[0122] In some embodiments, the movable trolley may be configured with an electrical / pneumatic interface.

[0123] In some embodiments, the movable cart may be configured to track new and used consumables, such as solder paste boxes, on the movable cart, including tracking their location, temperature, and other data.

[0124] In some embodiments, the movable cart may be configured to scan all consumables with a suitable scanning device, such as a barcode reader or RFID reader.

[0125] In some embodiments, the movable cart may be configured with an indexing mechanism to properly position the consumables.

[0126] In some embodiments, the movable cart may be configured with a bypass switch to disconnect the movable cart from the stencil printer in the event of a problem with the movable cart.

[0127] In some embodiments, the movable trolley may be configured to be actively or passively climate controlled.

[0128] In some embodiments, the movable trolley may be configured to be controlled by an application (App) that can be integrated into a smartphone.

[0129] As used herein, "automatic" or "fully automated" changeover describes the replacement or replenishment of items without human intervention.

[0130] As used herein, a "partially automated" changeover describes the replacement or replenishment of items with some or limited human intervention.

[0131] As used herein, "conveying" or "in conveyance" describes moving items from one location to another, either manually or by machine.

[0132] As used herein, "installation" or "in installation" describes the process of placing an item in a position ready for use.

[0133] The concepts disclosed herein can be used in other types of equipment used to manufacture electronic substrates, including pick and place machines, reflow ovens, wave soldering machines, selective soldering machines, inspection stations, and cleaning stations. For example, the concepts involving changing tools can be used in pick and place machines used to mount electronic components on electronic substrates. In another example, the concepts involving changing items can be used to change solder in wave soldering machines and selective soldering machines and to clean products in cleaning stations.

[0134] Thus, having described several aspects of at least one embodiment, it will be appreciated that various changes, modifications and improvements will readily occur to those skilled in the art. Such changes, modifications and improvements are intended to be a part of the present disclosure and are intended to fall within the scope of the present disclosure. Therefore, the previous description and drawings are intended only as examples.

[0135] Claims.

Claims

1. A movable pulley, comprising: a housing configured to move along a horizontal surface; a plurality of shelves supported by the housing, each shelf of the plurality of shelves being configured to move between a retracted position in which the shelf is located within the housing and an extended position in which the shelf is extended from the housing; as well as A sensing system is configured to determine whether each shelf of the plurality of shelves is in the retracted position and a type of item supported by the shelf.

2. The movable trolley according to claim 1, wherein: For each shelf, the sensing system includes at least one sensor coupled to the housing and at least one flag coupled to the housing.

3. The movable trolley according to claim 1, wherein: For each shelf, the sensing system includes a first sensor associated with a first flag located at an upper position relative to the shelf and a second sensor associated with a second flag located at a lower position relative to the shelf.

4. The movable trolley according to claim 3, wherein: When the shelf is in a retracted position within the housing of the movable trolley, the sensor is configured to return one of the following signals: Upper low (off) and lower low (off) = shelf empty; Up high (open) and down low (closed) = loading tool tray; Up low (off) and down high (on) = unload tool tray; and Upper High (Open) and Lower High (Open) = Template.

5. The movable trolley according to claim 4, wherein: The first sensor and the second sensor are further configured to generate a signal regarding whether the item is fully inserted into its corresponding shelf.

6. A method for determining whether a shelf of a movable trolley is in a retracted position, the method comprising: Flags associated with the racks are sensed to determine the positions of the racks.

7. The method of claim 6, further comprising: A first sensor is provided, the first sensor being associated with a first flag located at an upper position relative to the shelf, and a second sensor being associated with a second flag located at a lower position relative to the shelf.

8. The method of claim 7, wherein: When the shelf is in a retracted position within the housing of the movable trolley, the sensor is configured to return one of the following signals: Upper low (off) and lower low (off) = shelf empty; Up high (open) and down low (closed) = loading tool tray; Up low (off) and down high (on) = unload tool tray; and Upper High (Open) and Lower High (Open) = Template.

9. The method of claim 8, wherein: The first sensor and the second sensor are further configured to generate a signal regarding whether the item is fully inserted into its corresponding shelf.

10. A system for mechanically and electrically coupling a movable trolley to a stencil printer, the stencil printer having at least one of a plurality of articles for replacement within the stencil printer, the stencil printer comprising a docking station configured to receive the movable trolley, the movable trolley being configured to receive old articles and / or provide new articles to the stencil printer, the system comprising: a first interface panel associated with one of the stencil printer and the movable carriage, the first interface panel comprising a locking magnet and an array of metal disks; as well as a second interface panel associated with the other of the stencil printer and the movable carriage, the second interface panel comprising a metal plate and a contact array, Wherein, when the movable sled is docked to the stencil printer, the locking magnets of the first interface panel are configured to magnetically secure the metal plate of the second interface panel, and the contact array of the second interface panel is configured to engage the metal disk array of the first interface panel.

11. The system of claim 10, wherein: The first interface panel is associated with the stencil printer and the second interface panel is associated with the movable cart.

12. The system of claim 11, further comprising: a third interface panel associated with the stencil printer and spaced apart from the first interface panel; and a fourth interface panel associated with the movable carriage and spaced apart from the second interface panel.

13. The system of claim 10, wherein: The metal plate is a steel plate.

14. The system of claim 10, wherein: The locking magnets of the first interface panel are configured to communicate with a controller associated with the movable cart or a controller of the stencil printer to control operation of the locking magnets to secure or unlock the movable cart from the stencil printer.

15. The system of claim 10, wherein: The contact array includes a plurality of spring contacts.

16. The system of claim 15, wherein: The metal disks include a plurality of hard gold disks.

17. The system of claim 10, further comprising: A guide assembly is used to guide the movable trolley to the stencil printing machine when the movable trolley is docked to the stencil printing machine.

18. The system of claim 17, wherein: The guide assembly includes at least one forward facing roller secured to a housing of the movable trolley, the at least one forward facing roller being configured to contact at least one guide disposed on a face of the stencil printer.

19. The system of claim 18, wherein: The at least one forward-facing roller includes two spaced-apart forward-facing rollers, and the at least one guide includes two spaced-apart guides, the two spaced-apart forward-facing rollers being configured to contact the two spaced-apart guides to guide the movable sled relative to the stencil printer.

20. A method for mechanically and electrically coupling a movable trolley to a stencil printer, the stencil printer having at least one of a plurality of items for replacement within the stencil printer, the stencil printer comprising a docking station configured to receive the movable trolley, the movable trolley configured to receive old items and / or provide new items to the stencil printer, the system method comprising: providing a first interface panel associated with one of the stencil printer and the movable carriage, the first interface panel including a locking magnet and an array of metal disks; providing a second interface panel associated with the other of the stencil printer and the movable carriage, the second interface panel comprising a metal plate and a contact array; magnetically securing the metal plate of the second interface panel to the locking magnets of the first interface panel; and The array of metal pads of the first interface panel is engaged with the array of contacts of the second interface panel.

21. The method of claim 20, wherein: The first interface panel is associated with the stencil printer and the second interface panel is associated with the movable cart.

22. The method of claim 21, further comprising: a third interface panel associated with the stencil printer and spaced apart from the first interface panel; and a fourth interface panel associated with the movable carriage and spaced apart from the second interface panel.

23. The method of claim 20, wherein: The locking magnets of the first interface panel are configured to communicate with a controller associated with the movable cart or a controller of the stencil printer to control operation of the locking magnets to secure or detach the movable cart to or from the stencil printer.

24. The method of claim 20, further comprising: When the movable carriage is docked to the stencil printing press, movement of the movable carriage to the stencil printing press is guided.

25. The method of claim 24, wherein: Guiding movement of the movable trolley includes a guide assembly having at least one forward facing roller secured to a housing of the movable trolley, the at least one forward facing roller being configured to contact at least one guide disposed on a face of the stencil printer.

26. The method of claim 25, wherein: The at least one forward-facing roller includes two spaced-apart forward-facing rollers, and the at least one guide includes two spaced-apart guides, the two spaced-apart forward-facing rollers being configured to contact the two spaced-apart guides to guide the movable sled relative to the stencil printer.

27. A system for measuring assembly material in a cartridge of a stencil printer, the stencil printer comprising a turntable configured to support at least one cartridge, the system comprising: A laser height sensor is coupled to a frame of the stencil printer, the laser height sensor being positioned above the at least one cartridge barrel and configured to generate a laser beam toward the at least one cartridge barrel to determine a height of assembly material within the at least one cartridge barrel.

28. A method of measuring assembly material in a cartridge of a stencil printer, the stencil printer comprising a turntable configured to support at least one cartridge, the method comprising: sensing a height of assembly material within the at least one cartridge supported by the turntable; as well as If it is determined that the at least one cartridge is empty, an alarm is provided to replace the at least one cartridge with a new cartridge, and if it is determined that the at least one cartridge has a sufficient amount of assembly material, the at least one cartridge is continuously used.

29. The method of claim 28, wherein: Sensing the height of the assembly material is accomplished by a laser height sensor coupled to the frame of the stencil printer.

30. The method of claim 29, wherein: The laser height sensor is positioned above the at least one cartridge and is configured to generate a laser beam toward the at least one cartridge to determine a height of assembly material within the at least one cartridge.

31. The method of claim 29, further comprising: The laser height sensor is calibrated to determine a zero reference position.

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