System and method for replacing articles in stencil printers

Abstract

A method for replacing articles in a stencil printer includes removing a used stencil from the stencil printer, inserting an empty tool tray into the stencil printer, removing a used doctor blade from a print head, positioning the used doctor blade in the empty tool tray, removing a used tool from a support assembly, and replacing articles in the stencil printer. The method comprises the steps of placing a used scraper blade in an empty tool tray, positioning the used scraper blade in the empty tool tray, removing the tool tray with the used scraper blade and the used tool from the stencil printing machine, inserting the loaded tool tray into the stencil printing machine, the loaded tool tray having a new scraper blade and a new tool, in one embodiment, a stencil printer is configured to load a tool tray, mount a new tool on a support assembly, mount a new doctor blade on a print head, remove the loaded tool tray from the stencil printer, and mount a new stencil in the stencil printer.

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 onto 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 a job change, 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 job change 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 method for replacing items in a stencil printer. In one embodiment, the method includes: removing a used stencil from the stencil printer; inserting an empty tool tray into the stencil printer; removing a used scraper blade from a print head of the stencil printer; positioning the used scraper blade in the empty tool tray; removing the used tool from a support assembly of the stencil printer; positioning the used tool in the empty tool tray; removing the tool tray with the used scraper blade and the used tool from the stencil printer; inserting a loaded tool tray into the stencil printer, the loaded tool tray having a new scraper blade and a new tool; installing the new tool on the support assembly of the stencil printer; installing the new scraper blade on the print head of the stencil printer; removing the loaded tool tray from the stencil printer; and installing a new stencil in the stencil printer.

[0008] Embodiments of the method may further include: when inserting an empty tool tray into the stencil printer, verifying the position of the empty tool tray. Verifying the position of the empty tool tray may include capturing an image of the empty tool tray and determining the position of the empty tool tray using visual registration verification software. Capturing the image of the empty tool tray may be achieved by an imaging system of the stencil printer. The visual registration verification software may be associated with a controller of the stencil printer. Inserting a loaded tool tray into the stencil printer may include capturing an image of the loaded tool tray and determining the position of the loaded tool tray using visual registration verification software. Capturing the image of the loaded tool tray may be achieved by an imaging system of the stencil printer. The visual registration verification software may be associated with a controller of the stencil printer. Removing a used stencil, inserting an empty tool tray, removing a tool tray with a used scraper blade and a used tool, inserting a loaded tool tray, removing a loaded tool tray, and installing a new stencil may be achieved by using a tool pin associated with a print head and a print head gantry of the stencil printer. A movable trolley may be used to deliver the stencil and tool tray and remove it from the stencil printer. The movable trolley may include an interface configured to interact with a docking station associated with a stencil printer. The empty tool tray may include supports for a front scraper blade and a rear scraper blade and supports for tools. The method may be performed without requiring human intervention. The method may further include identifying the article by obtaining an image of the article and verifying whether the article is the correct article based on a predetermined identification mark. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 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:

[0010] Figure 1 It is a front perspective view of a stencil printing machine;

[0011] Figure 2 It is a front view of the stencil printing machine;

[0012] Figure 3 yes Figure 2 A plan view of the stencil printing press shown in , with some parts removed;

[0013] Figure 4 is a perspective view of a movable trolley of an embodiment of the present disclosure, the movable trolley being adjacent to a stencil printing press;

[0014] Figure 5 is a flow chart showing a sequence for changing an article in a stencil printing machine;

[0015] Figure 6 It is a three-dimensional image of an empty tool tray;

[0016] Figure 7 is a perspective view of a tool tray with a scraper blade and tools; and

[0017] Figure 8 is a perspective view of a tool tray with a scraper blade and tools and an end effector for securing the scraper blade. DETAILED DESCRIPTION

[0018] 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.

[0019] For the purpose of illustration only and not to limit 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 singular form herein may also cover embodiments including plural items, and any reference to the plural form of any embodiment, component, element or action herein may also include embodiments covering only singular items. References in singular or plural form are not intended to limit the currently disclosed systems or methods, their components, actions or elements. The use of "including", "consisting of...", "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 inconsistent usage of terms between this document and documents incorporated herein by reference, the usage of the terms in the incorporated referenced documents supplements the usage of the terms in this document; for contradictory inconsistencies, the usage of the terms in this document controls.

[0020] 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 the embodiment, the stencil printer 5 is an Edison supplied by ITW Electronics Assembly Equipment Company of Hopkinton, Massachusetts. TMSeries of stencil printing machine platforms.

[0021] 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.

[0022] 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 placed over the stencil 18 and may be lowered in the z-axis direction into contact with the stencil to form a seal with the stencil.

[0023] 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.

[0024] 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.

[0025] In one embodiment, the 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 solder paste box. For example, solder paste can be manually deposited between the blades or deposited from an external source. In addition, in one embodiment, the controller 14 can be configured to use a computer with a suitable operating system (such as Microsoft Windows provided by Microsoft Corporation). 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.

[0026] 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 through the aperture in the stencil 18 onto the circuit board 29. Once the print head assembly has completely traversed the aperture in 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 transported 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.

[0027] 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 on the circuit board 29 along 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 along the length of the beam in the x-axis direction. 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.

[0028] 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.

[0029] 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.

[0030] In one embodiment, a method for replacing stencils and / or articles placed on a tool tray may include placing clean stencils and / or articles on a movable trolley when a request for a new stencil and / or article placed on a tool tray is issued for a new production run or because an existing stencil and / or article is worn. On the production line, the "dirty" or used stencil and / or article is removed from the stencil printer, and the "clean" or new stencil and / or article is inserted from the movable trolley into the stencil printer and secured for use. The dirty stencil and / or article is transported to a cleaning station where the stencil and / or article is cleaned and ready for reuse. Once cleaned, the stencil and / or article can be transported back to the stencil printer or warehouse, in which case the stencil and / or article can be reused during the same or different production runs.

[0031] Embodiments of the present disclosure relate to a delivery system that is configured to automate or partially automate the conversion process of a stencil printing machine and implement one or more methods described herein. In one embodiment, the delivery system includes a movable pulley that is configured to engage the stencil printing machine to supply and receive replacement and supplementary parts and materials to the stencil printing machine. For example, the stencil printing machine may include a docking station configured to receive the movable pulley. The docking station may include an interface that enables the movable pulley to communicate with the stencil printing machine. A single movable pulley may be configured to include a conversion stencil and / or a replacement stencil. During conversion, for example, the stencil printing machine must be reconfigured to produce different items. Therefore, new stencils can be used in the stencil printing machine to produce different products.

[0032] The conversion process described herein can be achieved by a single movable pulley configured to replace and / or replenish each item. In other embodiments, more than one movable pulley can be provided. For example, for stencil conversion, the movable pulley is configured to support a predetermined number of stencils. The movable pulley and / or the stencil printer can be configured to identify stencils, store stencils, transport stencils to and from the stencil printer, inspect stencils, and interface with the stencil printer. The movable pulley can also be configured to remove used parts, such as stencils, from the stencil printer.

[0033] Embodiments of the present disclosure further relate to a delivery system configured to automate the replenishment process of a stencil printer. In one embodiment, the delivery system includes a movable trolley configured to engage the stencil printer to supply and receive replacement and replenishment parts and materials to the stencil printer. 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 and a replacement stencil.

[0034] The replenishment process described herein can be implemented by a single movable trolley configured to replenish replenishable items. In other embodiments, more than one movable trolley can be provided. For example, for stencil replenishment, the movable trolley is configured to support a number of replacement solder paste boxes. The movable trolley and / or the stencil printer can be configured to identify replacement solder paste boxes, store solder paste boxes, transport solder paste boxes to and from the stencil printer, inspect solder paste boxes, and interface with the stencil printer.

[0035] refer to Figure 4 , a movable trolley (generally indicated at 200) of an embodiment of the present disclosure is configured to remove and replace items (such as stencils, scraper blades, and tools) from a stencil printer (generally indicated at 205) and deliver the items to a cleaning station. When a request for new items is needed, either for a new production run or due to wear of existing items, clean items are transported to the stencil printer 205 by the movable trolley 200. "Dirty" or used items are removed from the stencil printer 205, and "clean" or new items are inserted into the stencil printer and secured for use. Dirty items are removed from the stencil printer 205 and new items are replaced within the stencil printer. These functions can be performed by the movable trolley 200.

[0036] As with the stencil printer 10, the stencil printer 205 can be configured to include a docking station configured to receive the movable trolley 200. The docking station can include an interface that enables the movable trolley 200 to communicate with the stencil printer 205. The movable trolley 205 can be configured with a matching interface that is designed to dock within a docking station provided on the stencil printer 205. This arrangement enables the movable trolley 200 to be configured to dock within the docking station of the stencil printer 205 from both a mechanical interface and an electronic communication interface. The movable trolley 200 can be configured with a unique mechanical interface that mates with the unique mechanical interface of the stencil printer 205. The unique mechanical interface can include geometric features. The movable trolley 200 can be configured with a pin that can be received in a guide associated with the stencil printer 205 to align the movable trolley with the stencil printer, thereby fully docking the movable trolley. Other types of guides may be used, such as electrical / magnetic guides, visual guides, sensors, latches, etc.

[0037] refer to Figure 5 , the order of replacing items within a stencil printer, such as stencil printer 205, is shown and described below. In order to effectively utilize the ability of the stencil printer to automatically replace stencils, scraper blades, and workpiece holding tools, a specific order of removing and replacing items is preferred. The order is formed within and around the physical constraints of the stencil printer. It should be understood that the order of replacing items within a stencil printer disclosed herein can be adjusted to accommodate any custom needs of the stencil printer or movable trolley.

[0038] The print head and print head gantry are used to transfer and precisely position a tool tray. The tool tray is configured to hold scraper blades and tools used within a stencil printer. When the print head and print head gantry use press vision registration to position the tool tray within the stencil printer, the scraper blades and tools can be transferred from or to the tool tray using the press print head gantry. In one embodiment, an imaging system (e.g., imaging system 30) can be used to capture an image of the tool tray and determine the location of the tool tray using press vision registration software associated with a controller (e.g., controller 14).

[0039] Changing a complete stencil printing press with replaceable items requires removing the stencil from the stencil printing press and unloading the squeegee blade and tooling, followed by loading a new squeegee blade and tooling and inserting the new stencil into the press. Figure 5 , which shows a method 500 that specifies an order for changing items in a stencil printer, the order for automatic printer tool change is as follows: At 502, an existing stencil is removed from the stencil printer.

[0040] At 504, an empty tool tray is inserted into the stencil printer using the print head and print head gantry. The empty tool tray can be delivered to the stencil printer by an operator or by a movable trolley. The position of the tool tray is verified by using visual registration verification software associated with the controller. As described above, an imaging system can be used to capture an image of the empty tool tray and send the image to the controller for verification.

[0041] After the location of the tool tray is determined, the front and rear scraper blades are removed and placed in the tool tray. Next, the tools are picked up and placed in the tool tray by using tool pins associated with the print head and print head gantry. Once the scraper blades and tools are placed in the tool tray, the tool tray is removed from the stencil printer.

[0042] At 506, the loaded tool tray is inserted into the stencil printer using the print head and print head gantry of the stencil printer. The loaded tool tray can be delivered to the stencil printer by an operator or by a movable trolley. Specifically, the loaded tool tray includes new front and rear scraper blades and new tools, which are intended to replace used scraper blades and used tools previously removed from the stencil printer, or any combination required by the process. Next, the tool tray is positioned within the stencil printer using stencil printer vision registration verification software associated with the controller. As with positioning an empty tool tray, an imaging system can be used to capture an image of the loaded tool tray and send the image to the controller for verification.

[0043] Next, the new tool is placed on the stencil printer work holding table (e.g., support assembly 28) using tool pins associated with the stencil printer's print head and print head gantry. Next, the new front and rear squeegee blades are picked up and installed on the print head. After the new tool and squeegee blades are installed, the tool tray is removed from the stencil printer.

[0044] A new stencil is inserted into the stencil printer at 508. At this point, the sequence of replacing items in the stencil printer is complete.

[0045] The movable trolley can be configured to hand over and remove the stencil and tool tray from the stencil printer. For example, in one embodiment, the stencil printer can be configured to move the stencil and tool tray to a suitable position in which the movable trolley is configured to end the removal. The stencil and / or tool tray can be moved and positioned within the stencil printer via tool pins associated with the print head and the print head gantry. Specifically, the tool pins can be used to engage the stencil and / or tool tray to move the stencil and / or tool tray laterally within the stencil printer.

[0046] refer to Figure 6, an empty tool tray is indicated at 600. As shown, the tool tray 600 includes a support 602 for a front scraper blade and a rear scraper blade. The tool tray 600 further includes a support 604 for tools.

[0047] refer to Figure 7 , tool tray 600 is shown supporting a front scraper blade and a rear scraper blade, both indicated at 702, on supports 602. Tool tray 600 is further shown supporting a tool 704 on supports 604. Tool tray 600 may be configured to support any type of item that needs to be replaced within a stencil printer.

[0048] In some embodiments, tool tray 600 includes a rectangular or square frame and a flat body. The size of the frame can be determined to be the same as the size of the template (e.g., template 18) frame. Tool tray 600 can be made of a lightweight but tough material, such as an aluminum alloy. The body of tool tray 600 includes a support 602 for a scraper blade and a support 604 for a tool. As described above, the size and shape of tool tray 600 can be substantially the same as the form factor of the template to allow the tool tray to be carried and stored / removed in a manner substantially the same as the template. For example, tool tray 600 can be customized to have a certain size, for example, 15 inches by 15 inches, 20 inches by 20 inches, 23 inches by 23 inches, and 29 inches by 29 inches. Stencil printer 205 and movable pulley 200 are particularly suitable for carrying templates and tool trays in a common manner. The movable trolley 200 is configured to partially deliver the tool tray 600 from the movable trolley to the stencil printer 205, and the stencil printer is configured to receive the tool tray in the remaining stroke. For example, a transport arm can be used to push the tool tray 600 away from the carriage of the movable trolley 200 and retract the tool tray into the movable trolley.

[0049] In some embodiments, tool tray 600 may include fiducials that may be viewed by an imaging system (e.g., imaging system 30 of stencil printer 10) to establish alignment with parts and locations on the tool tray. Methods of aligning and verifying tool tray 600 by capturing and verifying fiducial locations may be employed.

[0050] refer to Figure 8, a print head assembly (e.g., print head assembly 20) of a stencil printer includes an end effector, generally indicated at 800, which may be configured to pick up and release items from a tool tray 600. As previously described, with stencil printer 10, print head assembly 20 is mounted on print head assembly gantry 22, which moves the print head assembly in the y-axis direction under the control of controller 14. Print head assembly 20 is configured to move in the z-axis direction as described above.

[0051] In one embodiment, the end effector 800 can be configured to pick up and release the scraper blade 702. The end effector 800 is configured to engage and release the scraper blade 702 without the aid of a tool to attach and remove the scraper blade from the printhead assembly 20. In one embodiment, the tool tray 600 can be configured with a spring-loaded locking mechanism to secure the scraper blade holder of the scraper blade 702 to the end effector 800 of the printhead assembly 20. A method can be performed by the end effector 800 to passively pick up and put down the scraper blade 702 without the need for additional axes or actuators.

[0052] In one embodiment, end effector 800 includes a rectangular body 802 that is secured to printhead assembly 20 via a pair of linkages, each indicated at 804. End effector 800 may also be configured with a pair of downwardly extending pins that are configured to Figure 8 The illustrated arrangement releasably secures the scraper blade 702. The pins may also be used to manipulate the stencil and / or tool tray by moving the stencil and / or tool tray laterally within the stencil printer.

[0053] In some embodiments, the empty tool tray and loaded tool tray may be implemented as a single tool tray configured to support new front and rear scraper blades and new tools as well as used scraper blades and used tools previously removed from the stencil printer.

[0054] In some embodiments, the movable cart 200 is configured to receive a tool tray configured to store items (such as scraper blades, tools, and / or paste trays) in a desired position (such as a horizontal position) in the cleaner.

[0055] 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 control area network (CAN) bus or other types of networks. In other embodiments, a master controller can be provided to control the operation of the controllers of the movable pulleys. 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 clean and used stencils or articles arranged on a tool tray. 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.

[0056] In other embodiments, the movable trolley may be controlled by a controller of the stencil printer and / or a controller associated with the production line. The controller may be a controller dedicated to one or more movable trolleys.

[0057] In some embodiments, the material identification for the items on the movable trolley may include a device for manipulating the items and a scanner for scanning and identifying the items. In one embodiment, a barcode for identifying the items may be implemented. For example, the barcode may include a 1D scanner for a UPC code, a 2D scanner for a QRC code, a printed mark applied to the item, or a laser etched mark etched on the item. In another embodiment, an RFID system for identifying the items may be implemented. For example, the RFID system may 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 may be implemented. The visual system may be an imaging system similar to the imaging system 30 associated with the stencil printer 10, and may be associated with the stencil printer, outside the stencil printer, or on the movable trolley.

[0058] 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 / pull 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 coordinate the delivery of items to the stencil printer.

[0059] The database may further be 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 in which the stencil printer and / or the movable trolley are 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 the information from the network into a database associated with the movable trolley and / or the stencil printer, which in turn is associated with the MES system.

[0060] 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 templates and / or tool trays.

[0061] The database can be configured to share predictive data when replacement / replenishment is needed. For example, the database can be configured to perform one or more operations with respect to storing information related to templates and / or tool trays. The database can be configured to share predictive data for other replaceable / consumable items, such as templates and / or tool trays.

[0062] The database may be configured to store data associated with batch traceability. Additionally, an RFID or mechanical key structure of the stencil frame of the plate or stencil is provided to ensure the correct alignment / orientation / direction / front-to-back / up-and-down arrangement of these items when inserted into the stencil printer. This information may be used to verify the correct orientation and / or assembly before the items are transported from the warehouse and / or before the items are installed in the stencil printer. Low cost readers may perform this function.

[0063] In some embodiments, the movable trolley can be configured to store material. The movable trolley can be configured to flexibly adapt to the location where the material comes from and goes to. In addition, the movable trolley can be configured to identify the location where a specific material is located on the movable trolley. In certain embodiments, whether by automatic delivery or by manual delivery, the location is remote, local, on the movable trolley and / or on the stencil printing machine.

[0064] 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, connect 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.

[0065] In some embodiments, the movable pulley can be configured to sort the items stored on the movable pulley. As described above, in one embodiment, a movable pulley can be provided to store, transport and deliver multiple resources, including but not limited to stencils and / or tool trays. In another embodiment, the movable pulley can be configured to store, transport and deliver a single resource or item to a stencil printer. For example, the movable pulley can be configured to store multiple stencils and / or tool trays. 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.

[0066] In some embodiments, the movable pulley can be configured to transport items from the movable pulley to the stencil printing machine and from the stencil printing machine to the movable pulley, and the height difference between the movable pulley and the stencil printing machine 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.

[0067] 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 multi-line balancing control requirements with one or more movable pulleys, as well as meet real-time on-demand material supply requirements on the production line.

[0068] 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 templates and / or tool trays. In one embodiment, a vision system associated with the movable trolley can be configured to obtain images of the items. The vision system in conjunction with the controller can be configured to inspect 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.

[0069] 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 cooperates 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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. In another embodiment, the items may be manually loaded and unloaded from the movable trolley.

[0074] 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 reply to receive the movable trolley on the stencil printing machine.

[0075] 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.

[0076] In some embodiments, the movable trolley can be configured with a dedicated power source. In one embodiment, the movable trolley includes a battery configured to power automated components disposed in the movable trolley (e.g., a mechanism for moving stencils and / or tool trays into and out of the movable trolley). In other embodiments, the movable trolley can be configured with an uninterruptible power supply. The power source can be configured to support startup when "docked" (high voltage from the stencil printer when docked, otherwise low voltage when not docked). The power source can be configured to recharge for autonomous operation, for example, recharging the battery with power provided by the stencil printer.

[0077] In some embodiments, the movable trolley can be configured to function in conjunction with the stencil printer. For example, the movable trolley can be configured to provide a handshake function with the stencil printer 10 before delivering an item, such as "Please give me stencil #1234". The movable trolley and stencil printer can be configured with a communication protocol and / or a library index of 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 stencil #1234", and / or the subsequent delivery of the item, such as "I now have stencil #1234". 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 items are ready for use, whether they need cleaning, etc.

[0078] 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 sent you template #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.

[0079] 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.

[0080] In some embodiments, the existing machine gantry, tracks, and print head of a stencil printer may be configured to shuttle articles in and out.

[0081] In some embodiments, the mobile cart may be configured to communicate with a stencil printer, a production line, and a warehouse associated with the production line.

[0082] In some embodiments, the movable trolley may be configured with an electrical / pneumatic interface.

[0083] In some embodiments, the movable cart can be configured to track new and used consumables (e.g., stencils and / or tool trays) on the movable cart, including tracking their location, temperature, and other data.

[0084] In some embodiments, the movable cart may be configured to store and supply stencils and / or items on the tooling tray for the duration of a production run.

[0085] 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.

[0086] In some embodiments, the movable cart may be configured with a guide mechanism to properly position the consumables.

[0087] In some embodiments, the movable cart may be configured with a bypass switch to disconnect the movable cart from the stencil printer 10 in the event of a problem with the movable cart.

[0088] In some embodiments, the movable trolley may be configured to be moved manually or by an automated guided vehicle (AGV).

[0089] In some embodiments, the movable cart may be configured to dock and interface with a stencil printer.

[0090] In some embodiments, the movable cart may be configured to service multiple stencil printers.

[0091] In some embodiments, the removable cart may be configured to be dedicated to one consumable item (eg, a stencil) or multiple consumable / convertible items.

[0092] In some embodiments, the movable cart may be configured to transport and deliver consumables to be cleaned at a remote station.

[0093] In some embodiments, the movable cart may be configured to be reloaded at a stockroom associated with the warehouse.

[0094] In some embodiments, the movable trolley may be configured to be actively or passively climate controlled.

[0095] In some embodiments, the movable trolley may be configured to be controlled by an application (App) that can be integrated into a smartphone.

[0096] As used herein, "automatic" or "fully automated" changeover describes the replacement or replenishment of items without human intervention.

[0097] As used herein, a "partially automated" changeover describes the replacement or replenishment of items with some or limited human intervention.

[0098] As used herein, "conveying" or "in conveyance" describes moving items from one location to another, either manually or by machine.

[0099] As used herein, "installation" or "in installation" describes the process of placing an item in a position ready for use.

[0100] As mentioned above, the movable trolley can be used to replace other items in the stencil printing machine. For example, the stencil wiper assembly includes consumables such as paper and solvent that can be automatically replaced by the movable trolley.

[0101] The concepts disclosed herein can be used for other types of equipment used to manufacture electronic substrates, including dispensers, pick and place machines, reflow ovens, wave soldering machines, selective soldering machines, and inspection stations. For example, the concepts involving changing paste boxes can be used for dispensers used to dispense viscous materials. In another example, the concepts involving changing tools can be used for dispensers and 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.

[0102] 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.

[0103] Claims.

Claims

1. A method for replacing an article in a stencil printing machine, the method comprising: removing a used stencil from the stencil printing machine; inserting an empty tool tray into the stencil printing machine; removing a used doctor blade from a print head of the stencil printer; positioning the used scraper blade in the empty tool tray; removing a used tool from a support assembly of the stencil printer; positioning the used tool in the empty tool tray; removing the tool tray with the used scraper blade and the used tool from the stencil printer; inserting a loaded tool tray having a new scraper blade and a new tool into the stencil printing machine; installing the new tool on a support assembly of the stencil printer; installing the new doctor blade on the print head of the stencil printer; removing the loaded tool tray from the stencil printing machine; and A new stencil is installed in the stencil printing machine.

2. The method of claim 1, wherein: Inserting the empty tool tray into the stencil printer includes verifying a position of the empty tool tray.

3. The method of claim 2, wherein: Verifying the position of the empty tool tray includes capturing an image of the empty tool tray and determining the position of the empty tool tray using vision registration verification software.

4. The method of claim 3, wherein: Capturing the image of the empty tool tray is accomplished by an imaging system of the stencil printer.

5. The method of claim 3, wherein: The visual registration verification software is associated with a controller of the stencil printer.

6. The method of claim 2, wherein: Inserting the loaded tool tray into the stencil printer includes capturing an image of the loaded tool tray and determining a position of the loaded tool tray using vision registration verification software.

7. The method of claim 6, wherein: Capturing an image of the loaded tool tray is accomplished by an imaging system of the stencil printer.

8. The method of claim 6, wherein: The visual registration verification software is associated with a controller of the stencil printer.

9. The method of claim 1, wherein: Removing the used stencil, inserting the empty tool tray, removing the tool tray with the used scraper blade and the used tool, inserting the loaded tool tray, removing the loaded tool tray, and installing the new stencil are accomplished using the tool pins associated with the print head and print head gantry of the stencil printer.

10. The method of claim 1, wherein: A movable trolley is used to deliver and remove stencils and tool trays from the stencil printer.

11. The method of claim 10, wherein: The movable cart includes an interface configured to interact with a docking station associated with the stencil printer.

12. The method of claim 1, wherein: The empty tool tray comprises supports for the front and rear scraper blades and for the tools.

13. The method of claim 1, wherein: The method is performed without the need for human intervention.

14. The method of claim 1, further comprising: The object is identified by obtaining an image of the object and verifying whether the object is the correct object based on predetermined identification marks.

15. The method of claim 1, wherein: The empty tool tray and the loaded tool tray are embodied as a single tool tray.

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