Dual-function tooling tray for stencil printers

Abstract

A dual-function tooling tray for a stencil printer includes a peripheral frame, a first frame member spaced from a first side of the peripheral frame, a second frame member spaced from a second side of the peripheral frame, and a third frame member extending between the first and second frame members and secured to the first and second frame members. The third frame member is configured to support at least one squeegee blade assembly. The tooling tray further includes a first support secured to the first frame member and a second support secured to the second frame member. The first and second supports are configured to support a tooling plate. The tooling tray further includes a third support secured to the first frame member and a fourth support secured to the second frame member. The third and fourth supports are configured to support a tooling plate.

Description

Technical Field

[0001] This application relates generally to stencil printers for printing a viscous material, such as solder paste, onto an electronic substrate, such as a printed circuit board (PCB), and more particularly to a system and method for exchanging items (articles, parts) within a stencil printer that includes a dual-functional tooling tray.

Background Art

[0002] When manufacturing surface mount printed circuit boards, a stencil printer can be used to print solder paste onto the circuit board. Typically, a circuit board having a pattern of pads or some other conductive surface, onto which the solder paste will be deposited, is automatically fed into the stencil printer, and one or more small holes or marks (known as "fiducials") on the circuit board are used to properly align the circuit board with the stencil or screen of the stencil printer before printing the solder paste onto the circuit board. In some systems, an optical alignment system embodying an imaging system or a vision system is used to align the circuit board with the stencil.

[0003] In the above printer, once the circuit board is properly aligned with the stencil, the circuit board is raised to the stencil, and solder paste is dispensed onto the stencil. A wiper blade (i.e., squeegee) traverses the stencil, pushing the solder paste onto the circuit board through the stencil's holes. As the squeegee moves across the stencil, the solder paste tends to spread out in front of the blade. This, desirablely, causes mixing and shearing of the solder paste, resulting in the desired viscosity to facilitate filling the screen, i.e., the holes in the stencil. The solder paste is typically dispensed onto the stencil from a standard cartridge. The stencil is then separated from the circuit board, and the majority of the material remains on the circuit board due to adhesion between the circuit board and the solder paste. The material remaining on the surface of the stencil is removed in a cleaning process before further circuit boards are printed.

[0004] Another process in printing circuit boards involves inspecting the circuit board after the solder paste has been deposited on its surface. Inspecting the circuit board is crucial for determining whether clean electrical connections can be formed. Too much solder paste can cause short circuits, while too little solder paste in the correct locations can impede electrical contact. Generally, imaging inspection systems are further utilized to provide two-dimensional or three-dimensional inspection of the solder paste on the circuit board.

[0005] Modern stencil printers require manual intervention to perform routine operations. For example, during a changeover, the operator must perform numerous manual tasks, such as changing stencils, replacing solder paste cartridges, changing squeegee blades, and replacing support tooling. Each of these tasks requires manual operation. For instance, in most stencil printers, the operator must unlock the stencil, remove it, properly insert the replacement stencil, and lock the replacement stencil in place. A changeover can take around 30 minutes, during which time the stencil printer is inoperable, potentially resulting in a downtime for the PCB manufacturing line. [Overview of the Initiative]

[0006] One aspect of the present disclosure relates to a dual-function tooling tray for a stencil printer. In one embodiment, the tooling tray comprises a perimeter frame having four sides; a first frame member spaced apart from a first side of the perimeter frame; a second frame member spaced apart from a second side of the perimeter frame, wherein the first and second sides of the perimeter frame are parallel to each other; and a third frame member extending between the first and second frame members and fixed to the first and second frame members. The third frame member is configured to support at least one squeegee blade assembly. The tooling tray further comprises a first support fixed to the first frame member and a second support fixed to the second frame member. The first and second support members together are configured to support a tooling plate. The touring tray further comprises a third support fixed to a first frame member and a fourth support fixed to a second frame member. The third and fourth support members together are configured to support the touring plate.

[0007] Embodiments of the tooling tray may further include positioning a first support and a second support adjacent to a third side of the perimeter frame, and positioning a third support and a fourth support adjacent to a fourth side of the perimeter frame. The first support and the second support may be spaced apart from each other by a predetermined distance sufficient to support the tooling plate. The third support and the fourth support may be spaced apart from each other by a predetermined distance sufficient to support the tooling plate. The tooling tray may further include a first support member connected at one end to a first side of the perimeter frame and at the opposite end to a first frame member. The tooling tray may further include a second support member connected at one end to a second side of the perimeter frame and at the opposite end to a second frame member. The first, second, third, and fourth support members each include a feature portion configured to engage with a mating feature portion associated with (attached to) a tooling plate for supporting the tooling plate. The feature portion may be a pin, and the mating feature portion may be an opening sized to receive a pin. At least one of the first and second support members, and at least one of the third and fourth support members, may each include a fiducial configured to be detected by an imaging system. The third frame member may be perpendicular to the first and second frame members. The third frame member may include at least one squeegee blade assembly support structure. The third frame member may further include a drip tray. The drip tray may be fixed to the bottom surface of the third frame member. The perimeter frame may be configured to engage with a gripper associated with the print head of a stencil printer.

[0008] Another aspect of this disclosure relates to a method for replacing items in a stencil printer. In one embodiment, the method involves preparing a tooling tray including a new tooling support and a new squeegee blade assembly support, and a used tooling support and a used squeegee blade assembly support, wherein the tooling tray includes a new tooling plate on the new tooling support and a new squeegee blade assembly on the new squeegee blade assembly support, and removing (detaching, removing) the used squeegee blade from the print head of the stencil printer and placing the used squeegee blade assembly on the tooling tray. This includes positioning the used squeegee blade assembly on the support section, removing the used tooling plate from the support assembly of the stencil printer, positioning the used tooling plate on the used tooling support section of the tooling tray, removing a new squeegee blade assembly from the tooling tray, installing the new squeegee blade assembly on the print head of the stencil printer, removing a new tooling plate from the tooling tray, and installing the new tooling plate on the support assembly of the stencil printer.

[0009] Embodiments of this method may further include passing the tooling tray to a stencil printer and moving the tooling tray within the stencil printer. Moving the tooling tray may be achieved by a gripper mechanism associated with the print head of the stencil printer. Passing the tooling tray to the stencil printer may include moving the tooling tray by a movable cart employed to pass the stencil and tooling tray and to remove the stencil and tooling tray from the stencil printer. This method may further include verifying the position of the tooling tray. Verifying the position of the tooling tray may include capturing an image of the tooling tray along with any fiducials provided on the tooling tray.

[0010] The attached drawings are not intended to be drawn to scale. In the drawings, identical or nearly identical components shown in various figures are represented by the same reference numerals. For clarity, not all components may be referenced in all drawings. [Brief explanation of the drawing]

[0011] [Figure 1] This is a front perspective view of the stencil printer. [Figure 2] This is a front view of a stencil printer. [Figure 3] Figure 2 is a top view of the stencil printer shown, with a portion removed. [Figure 4A] This is a perspective view of a dual-function tooling tray according to an embodiment of the disclosure. [Figure 4B] Figure 4A is a top view of the tooling tray, including some details of the tooling tray showing the fiducial. [Figure 5A] This is a perspective view of the tooling tray, showing the first (new) tooling and the first (new) squeegee blade assembly supported by the tooling tray. [Figure 5B] Figure 5A is a top view of the tooling tray shown. [Figure 6A] This is a perspective view of the tooling tray, showing a first (new) tooling, a first (new) squeegee blade assembly, and a second (used) squeegee blade assembly, all supported by the tooling tray. [Figure 6B] Figure 6A is a top view of the tooling tray shown. [Figure 7A] This is a perspective view of the tooling tray, showing a first (new) tooling, a first (new) squeegee blade assembly, a second (used) squeegee blade assembly, and a second (used) tooling, all supported by the tooling tray. [Figure 7B] Figure 7A is a top view of the tooling tray shown. [Figure 8A] This is a perspective view of a portion of the tooling tray and a gripper shown in relation to the tooling tray at a distance. [Figure 8B] Figure 8A is a perspective view of a portion of the tooling tray and a gripper engaged with the tooling tray. [Figure 9A] This is a perspective view of the tooling tray, showing a first (new) tooling, a second (used) squeegee blade assembly, and a second (used) tooling, supported by the tooling tray. [Figure 9B] Figure 9A is a top view of the tooling tray shown. [Figure 9C] Figures 9A and 9B show perspective views of the tooling tray, which is supported by the tooling tray and contains a first (new) tooling, a second (used) squeegee blade assembly, a second (used) tooling, and a frame member of the tooling tray operated by a gripper. [Figure 9D] Figure 9C is a top view of the tooling tray shown. [Figure 10A]A perspective view of a tooling tray showing a second (used) squeegee blade assembly and a second (used) tooling supported by the tooling tray. [Figure 10B] A top view of the tooling tray shown in FIG. 10A. [Figure 11A] A perspective view of a modified tooling. [Figure 11B] A top view of the modified tooling shown in FIG. 11A. [Figure 12A] An enlarged perspective view of a gripper of an embodiment of the present disclosure. [Figure 12B] An enlarged side elevation view of the gripper shown in FIG. 12A. [Figure 13A] An enlarged perspective view of a part of a print head assembly of a stencil printer showing a gripper. [Figure 13B] A rear elevation view of a part of the print head assembly shown in FIG. 13A.

Best Mode for Carrying Out the Invention

[0012] The present disclosure comprehensively relates to a material application machine (referred to as a "stencil printer", "screen printer", "printer", or "printing machine" in the present application) and other equipment that are used in a surface mount technology (SMT) process line and are configured to apply assembly materials (such as solder paste, conductive ink, or encapsulation materials) onto a substrate (referred to as an "electronic substrate", "circuit board", "board", "PCB", "PCB substrate", "substrate", or "PCB board" in the present application), or perform other operations such as inspection, rework, or placement of electronic components onto the substrate. Specifically, embodiments of the present disclosure will be described below with reference to a stencil printer used for manufacturing printed circuit boards.

[0013] For illustrative purposes only and not to limit its universality, the present disclosure is described in detail here with reference to the accompanying drawings. The present disclosure is not limited to the configuration details and arrangement of components described below or shown in the drawings, in terms of its applications. The principles described in this disclosure are also applicable to other embodiments and can be practiced or implemented in various ways. Furthermore, the expressions and terminology used in this application are for illustrative purposes only and should not be considered limiting. Any reference in this application to an example, embodiment, component, element, or operation of a system or method referred to singularly may also encompass embodiments containing multiple components, and any reference in this application to any embodiment, component, element, or operation as plural may also encompass embodiments containing only one component. References in singular or plural form are not intended to limit the systems or methods, their components, operations, or elements disclosed in this application. The use of the terms “including,” “equipped with,” “having,” “containing,” “accompanied by,” and variations thereof in this application means that the items listed before them, their equivalents, and additional items are included. A reference to “or / or” can be interpreted as comprehensive, such that any term described using “or / or” can refer to any single, two or more, or all of the terms described. In addition, if there is inconsistency in the use of terminology between the Application and any document that, by reference, forms part of the Application, the use of terminology in the document forming part of the Application is supplementary to the use in the Application, and the use of terminology in the Application shall prevail if the inconsistency results in a contradiction.

[0014] For illustrative purposes, embodiments of the present disclosure will be described below with reference to a stencil printer used for printing assembly materials, such as solder paste, onto a circuit board. However, those skilled in the art will understand that embodiments of the present disclosure are not limited to stencil printers for printing solder paste onto circuit boards, but can be used in other applications requiring the dispensing of other adhesive assembly materials, such as glues and sealants. For example, the apparatus can be used to print epoxy used as underfill for chip-scale packages. Furthermore, the stencil printers of embodiments of the present disclosure are not limited to those for printing assembly materials onto circuit boards, but include those used for printing other materials onto various substrates, such as semiconductor wafers. Also, the terms screen and stencil can be used interchangeably in this application to describe devices within a printer that define the pattern printed on the substrate. In certain embodiments, the stencil printer may include the Momentum® or Edison® series stencil printer platforms provided by ITW Electronic Assembly Equipment in Hopkinton, Massachusetts. An exemplary stencil printer is generally shown as 5 in Figure 1. In this embodiment, the stencil printer 5 is a Momentum® series stencil printer platform provided by ITW Electronic Assembly Equipment in Hopkinton, Massachusetts.

[0015] Referring to Figure 2, the stencil printer of an embodiment of the present disclosure is generally shown as 10. As shown, the stencil printer 10 has a frame 12 that supports the 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. The print head or print head assembly is generally shown as 20 and is configured to apply solder paste in the manner described in more detail below.

[0016] As shown in Figure 2 and described below, the stencil and printhead assembly can be connected to the frame 12 as appropriate, or otherwise connected. In one embodiment, the printhead assembly 20 can be mounted on a printhead assembly gantry 22, which can be mounted on the frame 12. The printhead assembly gantry 22 allows the printhead assembly 20 to move in the y-axis direction under the control of the controller 14 and to apply pressure to the printhead assembly by engaging with the stencil 18. In a particular embodiment, the printhead assembly 20 can be placed above the stencil 18 and descend in the z-axis direction to contact the stencil and form a seal together with the stencil.

[0017] The stencil printer 10 may also have a conveyor system having rails (not shown) for transporting printed circuit boards (which may be referred to in this application as "printed wiring boards," "boards," or "electronic boards") to the printing position within the stencil printer. The rails may be referred to in this application as a "tractor feed mechanism." The tractor feed mechanism is configured to feed, deliver, or otherwise deliver the circuit boards to the work area of ​​the stencil printer, which may be referred to in this application as a "print nest," and to discharge the circuit boards from the print nest.

[0018] Referring further to Figure 3, the stencil printer 10 has a support assembly 28 that supports the circuit board 29 (shown by a dashed line). The support assembly 28 raises and secures the circuit board so that it is stable during printing. In certain embodiments, the board support assembly 28 may further have a specific board support system, such as a rigid support, multiple pins, or flexible tooling, which is positioned below the circuit board when the circuit board is in the printing position. Part of the board support system can be used to support the internal region of the circuit board to prevent bending or warping of the circuit board during printing.

[0019] In one embodiment, the printhead assembly 20 may be configured to receive solder paste from a supply source, such as a dispenser or solder paste cartridge, which provides solder paste to the printhead assembly during printing operations. Other methods of supplying solder paste may be used instead of a cartridge. For example, solder paste can be manually deposited between blades or from an external supply source. In addition, in certain embodiments, the controller 14 may be configured to use a personal computer with a suitable operating system, such as the Microsoft Windows® operating system provided by Microsoft Corporation, and to control the operation of the stencil printer 10 using application-specific software. The controller 14 may be networked with a master controller used to control a production line for manufacturing circuit boards.

[0020] In one configuration, the stencil printer 10 operates as follows: The circuit board 29 is transported into the stencil printer 10 using a conveyor rail. A support assembly 28 raises and secures the circuit board 29 to the printing position. The print head assembly 20 is then lowered in the z-axis direction until the blades of the print head assembly contact the stencil 18 with the desired pressure. The print head assembly 20 is then moved in the y-axis direction across the stencil 18 by the print head assembly gantry 22. The print head assembly 20 deposits solder paste onto the circuit board 29 through the holes in the stencil 18. Once the print head assembly has completely traversed the stencil 18 across the holes, the print head assembly is lifted from the stencil, and the circuit board 29 is lowered back onto the conveyor rail. The circuit board 29 is released and transported from the stencil printer 10, thereby allowing a second circuit board to be transported 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.

[0021] An imaging system 30 may be provided for the purpose of aligning the stencil 18 with respect to the circuit board 29 before printing and for inspecting the circuit board after printing. In one embodiment, the imaging system 30 may be positioned between the stencil 18 and a support assembly 28 on which the circuit board is supported. The imaging system 30 is connected to an imaging gantry 32 for moving the imaging system. In one embodiment, the imaging gantry 32 may be connected to a frame 12 and has beams extending between the lateral rails of the frame 12, providing for 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 have a carriage device housing the imaging system 30, configured to move along the length of the beams in the x-axis direction. The structure of the imaging gantry 32 used to move the imaging system 30 is known in solder paste printing technology. The arrangement allows the imaging system 30 to be positioned at any position below the stencil 18 and above the circuit board 29 to capture images of predetermined areas of the circuit board or stencil, respectively.

[0022] 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 the stencil wiper assembly, generally shown as 34, can move below the stencil to remove the excess solder paste. In other embodiments, the stencil 18 may move above the stencil wiper assembly.

[0023] As mentioned above, stencil printers traditionally required manual intervention to replace and / or replenish certain parts. For example, a typical stencil needs to be replaced after a certain period, e.g., every four hours. Also, stencils need to be replaced for separate production runs. In addition, the solder paste cartridge that supplies temperature-controlled solder paste to the stencil printer needs to be replaced over time, e.g., every four hours. Different types of solder paste materials may be required for separate production runs. Another item that requires periodic replacement is the squeegee blade, which wears out with use. And finally, the tooling used to support the substrate at the printing position is replaced when changing from one production run to another.

[0024] In one embodiment, a method for replacing stencils and / or items placed on a tooling tray may include providing clean stencils and / or items on a mobile cart when a request for new stencils and / or items on the tooling tray is made for a new production run or due to wear and tear on existing stencils and / or items. On the production line, "unclean" or used stencils and / or items are removed from the stencil printer, and "clean" or new stencils and / or items are inserted from the mobile cart into the stencil printer and secured for use. Unclean stencils and / or items are transported to a washing station where the stencils and / or items are cleaned and prepared for reuse. Once cleaned, the stencils and / or items can be transported back to the stencil printer or storage room, and the stencils and / or items can be reused in the same or a different production run.

[0025] A specially designed tooling tray may be provided to accommodate the transport of new and used squeegee blade assemblies and tooling within the stencil printer. Referring to Figures 4A and 4B, in one embodiment, the tooling tray is generally shown as 40. As shown, the tooling tray 40 includes a square-shaped perimeter frame generally shown as 42, having four sides: a first side 44, a second side 46 parallel to the first side, a third side 48 connected to the ends of the first and second sides, and a fourth side 50 connected to the opposite ends of the first and second sides. In one embodiment, the tooling tray 40 is the same size and shape as the stencil 18 of the stencil printer 10. The touring tray 40 further includes a first frame member 52 that is separated from the first side 44 of the perimeter frame 42 and extends between the third side 48 and the fourth side 50 of the perimeter frame, and a second frame member 54 that is separated from the second side 46 of the perimeter frame and extends between the third side 48 and the fourth side 50 of the perimeter frame. As shown in the figure, the first side 44 of the perimeter frame 42, the first frame member 52, the second frame member 54, and the second side 46 of the perimeter frame are parallel to each other.

[0026] The tooling tray 40 further includes a third frame member 56 that extends between the first frame member 52 and the second frame member 54 and is fixed to the first frame member 52 and the second frame member 54. In one embodiment, the third frame member 56 includes two spaced rails 56a, 56b, each rail configured to support a squeegee blade assembly. Specifically, the first rail 56a of the third frame member 56 includes a squeegee blade assembly support structure 58 configured to support a squeegee blade assembly, preferably a new squeegee blade assembly. Spaced apart from the first rail 56a, the second rail 56b of the third frame member 56 includes a squeegee blade assembly support structure 62 configured to support a squeegee blade assembly, preferably a used squeegee blade assembly.

[0027] As shown in the figure, the third frame member 56 is perpendicular to the first frame member 52 and the second frame member 54. Furthermore, the third frame member 56 includes a drip tray 64 for collecting solder paste that may drip from the used squeegee blade assembly. As shown in the figure, the drip tray 64 extends between the first rail 56a and the second rail 56b of the third frame member 56. The used squeegee blade may contain excess solder paste discharged onto the squeegee blade assembly, and it is known that when excess solder paste drips from the squeegee blade assembly, it may drip onto the working or operating members of the stencil printer 10, or onto a printed circuit board supported by the stencil printer, such as the circuit board 29. This is undesirable. In one embodiment, the drip tray 64 is fixed to the bottom surface of the third frame member 56 under the squeegee blade assembly support structures 58, 62.

[0028] The tooling tray 40 further includes a first support portion 66 fixed to a first frame member 52 adjacent to a third side portion 48 of the perimeter frame 42, and a second support portion 68 fixed to a second frame member 54. The first support portion 66 and the second support portion 68 together are configured to support tooling. Specifically, both the first support portion 66 and the second support portion 68 extend inward relative to their respective frame members 52 and 54. In the illustrated embodiment, the first support portion 66 and the second support portion 68 are positioned adjacent to the third side portion 48 of the perimeter frame 42. Depending on the size of the tooling, the first support portion 66 and the second support portion 68 are separated from each other by a predetermined distance sufficient to support the tooling. In the illustrated embodiment, the first support portion 66 and the second support portion 68 are configured to support new tooling.

[0029] The first support portion 66 includes a support tab 70 extending toward the second support portion 68. The support tab 70 includes a feature portion extending upward (along the z-axis) from the support tab. This feature portion is configured to engage with a mating feature portion provided on one side of a tooling, for example, a new tooling. In one embodiment, this feature portion embodies a pin 72, and the mating feature portion embodies an opening formed in the bottom surface of the support tab provided on one side of the tooling. The structure of the tooling will be shown and described in more detail with reference to Figures 11A and 11B. The first support portion 66 further includes a smaller support tab 74, spaced apart from the support tab 70 and extending toward the second support portion 68.

[0030] Similarly, the second support portion 68 includes a support tab 76 extending toward the first support portion 66. The support tab 76 includes a feature portion extending upward (along the z-axis) from the support tab. This feature portion is configured to engage with a mating feature portion provided on the opposite side of the tooling to support the tooling. In one embodiment, this feature portion embodies a pin 78, and the mating feature portion embodies an opening formed in the bottom surface of the support tab provided on the opposite side of the tooling. The second support portion 68 further includes a smaller support tab 80, spaced apart from the support tab 76 and extending toward the first support portion 66. This configuration ensures that the support tab 70 and smaller support tab 74 of the first support portion 66 and the support tab 76 and smaller support tab 80 of the second support portion 68 each hold the tooling in the precise position for transfer from the tooling tray 40 to the stencil printer 10.

[0031] The tooling tray 40 further includes a third support portion 82 fixed to the first frame member 52 and adjacent to the fourth side portion 50 of the surrounding frame 42, and a fourth support portion 84 fixed to the second frame member 54. The third support portion 82 and the fourth support portion 84 together are configured to support tooling. Specifically, both the third support portion 82 and the fourth support portion 84 extend inward relative to their respective frame members 52 and 54. In the illustrated embodiment, the third support portion 82 and the fourth support portion 84 are positioned adjacent to the fourth side portion 50 of the surrounding frame 42. Depending on the size of the tooling, the third support portion 82 and the fourth support portion 84 are separated from each other by a predetermined distance sufficient to support the tooling. In the illustrated embodiment, the third support portion 82 and the fourth support portion 84 are configured to support used tooling.

[0032] The third support portion 82 and the fourth support portion 84 are configured in a manner similar to that of the first support portion 66 and the second support portion 68, respectively. The third support portion 82 includes a support tab 86 extending toward the fourth support portion 84. The support tab 86 includes a feature portion extending upward (along the z-axis) from the support tab. This feature portion is configured to engage with a mating feature portion provided on one side of a tooling, for example, a used tooling. In one embodiment, this feature portion embodies a pin 88, and the mating feature portion embodies an opening formed in the bottom surface of the support tab provided on one side of the tooling. The third support portion 82 further includes a smaller support tab 90, spaced apart from the support tab 86 and extending toward the fourth support portion 84. Similarly, the fourth support portion 84 includes a support tab 92 extending toward the third support portion 82. The support tab 92 includes a feature portion extending upward (along the z-axis) from the support tab. This feature portion is configured to engage with a mating feature portion provided on the opposite side of the tooling to support the tooling. In one embodiment, this feature portion embodies a pin 94, and the mating feature portion embodies an opening formed in the bottom surface of the support tab provided on the opposite side of the tooling. The fourth support portion 84 further includes a smaller support tab 96 that is spaced apart from the support tab 92 and extends toward the third support portion 82. This configuration ensures that the support tab 86 and smaller support tab 90 of the third support portion 82, and the support tab 92 and smaller support tab 96 of the fourth support portion 84, respectively, hold the tooling in the precise position for transfer from the stencil printer 10 to the tooling tray 40.

[0033] Referring particularly to Figure 4B, in some embodiments, the first support portion 66 of the tooling tray 40 includes a fiducial 100 provided to be detected by a visual system such as the imaging system 30 of the stencil printer 10. The fiducial 100 may be located on the bottom surface of the support tab 70 of the first support portion 66, directly below the feature portion, i.e., the pin 72. Similarly, the second support portion 68 may include an optional fiducial provided to be detected by an imaging system. This fiducial may be located on the bottom surface of the support tab 76 of the second support portion 68, directly below the feature portion, i.e., the pin 78. Providing two fiducials allows for more precise positioning of new tooling on the first support portion 66 and the second support portion 68 before removal from the tooling tray.

[0034] Similarly, in some embodiments, the third support 82 includes a fiducial similar to fiducial 100, which is provided to be detected by the imaging system. This fiducial may be located on the bottom surface of the support tab 86 of the third support 82, directly below the feature portion, i.e., the pin 88. Similarly, the fourth support 84 may include an optional fiducial, which is provided to be detected by the imaging system. This fiducial may be located on the bottom surface of the support tab 92 of the fourth support 84, directly below the feature portion, i.e., the pin 94. Providing two fiducials, as with the first support 66 and the second support 68, allows for more precise positioning of used tooling on the third support 82 and the fourth support 84 when positioned on the tooling tray.

[0035] To assist in stabilizing the tooling tray 40, the tooling tray includes a first support member 102, which is connected at one end to a first side 44 of the perimeter frame 42 and at the opposite end to a first frame member 52, and a second support member 104, which is connected at one end to a second side 46 of the perimeter frame 42 and at the opposite end to a second frame member 54. As shown in the figure, each of the first support member 102 and the second support member 104 is positioned midway between the respective frame members 52 and 54. The support members 102 and 104 assist in stabilizing the first frame member 52 and the second frame member 54 relative to the perimeter frame 42.

[0036] Referring to Figures 5A and 5B, the tooling tray 40 is shown supporting a new tooling 110 and a new squeegee blade assembly, including a front squeegee blade subassembly 120a and a rear squeegee blade subassembly 120b. The front squeegee blade subassembly 120a and the rear squeegee blade subassembly 120b may together be referred to as the squeegee blade subassembly 120. As shown, the new tooling 110 is supported by a first support 66 and a second support 68, the front squeegee blade subassembly 120a is supported by a squeegee blade assembly support structure 58 on the first rail 56a of the third frame member 56, and the rear squeegee blade subassembly 120b is supported by a squeegee blade assembly support structure 62 on the second rail 56b of the third frame member. In one embodiment, when the tooling tray 40 is manually handed to the stencil printer, the tooling tray is pushed into the stencil printer from its fully inserted position to a predetermined distance, for example, 70 millimeters (mm). In another embodiment, the tooling tray 40 is pushed into a known position and then moved to the 70 mm position using a gripper mechanism associated with the stencil printer, as shown with reference to Figures 8A, 8B, 12A, 12B, 13A, and 13B. In yet another embodiment, when the tooling tray 40 is handed to the stencil printer using an automated delivery device, for example, a movable cart, the tooling tray is pulled into the stencil printer from the sleeve of the automated delivery device to the 70 mm position from its fully inserted position.

[0037] Referring to Figures 6A and 6B, the tooling tray 40 is shown supporting a used squeegee blade assembly, including a front squeegee blade subassembly 130a and a rear squeegee blade subassembly 130b, in addition to the new tooling 110 and new squeegee blade assembly 120 shown in Figures 5A and 5B, respectively, supported by a squeegee blade assembly support structure 58 on the first rail 56a and a squeegee blade assembly support structure 62 on the second rail 56b of the third frame member 56. The front squeegee blade subassembly 130a and the rear squeegee blade subassembly 130b may together be referred to as the squeegee blade subassembly 130. As shown, the drip tray 64 prevents unwanted solder paste from dripping into the internal compartments of the stencil printer. In one embodiment, a gripper mechanism may be used to position and align the tooling tray 40 prior to receiving the used squeegee blade assembly 130.

[0038] Referring to Figures 7A and 7B, the tooling tray 40 is shown supporting the new tooling 110, new squeegee blade assembly 120, and used squeegee blade assembly 130 shown in Figures 6A and 6B, as well as the used tooling 140 supported by the third support 82 and the fourth support 84. The tooling tray 40 is fully loaded with the new tooling 110 and used tooling 140, as well as the new squeegee blade assembly 120 and used squeegee blade assembly 130.

[0039] Referring to Figures 8A, 8B and 12A, 12B, 13A, and 13B, in one embodiment, the gripper mechanism generally shown as 150 includes a pair of spaced gripper arms 152, 154 designed to engage with and move the tooling tray 40 (and stencil). As shown, each gripper arm 152, 154 includes a downwardly extending toe portion 156 and a downwardly extending middle portion 158, which together define a recess 160 sized to receive the retaining portion 162 of the tooling tray 40, in the manner shown in Figures 8A and 8B. Specifically, the gripper arm 152 of the gripper mechanism 150 is spaced away from the tooling tray 40 with the recess 160 positioned above the retaining portion 162 of the tooling tray. The gripper arm 152 of the gripper mechanism 152 engages with the perimeter frame 42 of the tooling tray 40 with the retaining portion 162 of the tooling tray received in the recess 160 of the gripper arm. Each gripper arm 152, 154 further includes a downward-extending heel portion 164 used to slide or move the tooling tray 40 (or stencil) by engaging with the perimeter frame 42.

[0040] Referring to Figures 9A and 9B, the tooling tray 40, as shown in Figures 7A and 7B, is shown with the new squeegee blade assembly 120 removed from the tooling tray and installed in the printhead assembly of the stencil printer. The tooling tray 40 is positioned and aligned to remove the new squeegee blade assembly 120 and position the assembly within the stencil printer. With the new squeegee blade assembly 120 removed, there is space within the stencil printer for removing and positioning the new tooling 110.

[0041] In addition, referring to Figures 9C and 9D, when additional capacity in the tooling tray 40 is desired, the frame member 56 is repositioned within the tooling tray by tooling pins, each indicated by 60, which are associated with the print head and print head gantry. This additional space creates room for removing and placing new tooling 110 within the stencil printer.

[0042] Referring to Figures 10A and 10B, the tooling tray 40, as shown in Figures 9A and 9B, is shown here with new tooling 110 removed from the tooling tray and placed on the substrate support of the stencil printer. The tooling tray 40 is ready to be completely removed from the stencil printer. A gripper mechanism 150 is employed to move the tooling tray 40 to a desired position where it can be removed manually from the stencil printer or by an automated delivery device.

[0043] Referring to Figures 11A and 11B, an exemplary tooling is generally shown as 170. As illustrated, the tooling 170 includes a rectangular tooling plate 172 and two outwardly extending support tabs 174, 176 provided at opposing ends of the tooling plate. Each support tab 174 includes the respective openings 178, 180 described above. Each opening is sized to receive the respective pins from the tooling tray, for example, the pins 72, 78 of the first support 66 and the second support 68, respectively.

[0044] Referring to Figures 12A, 12B, 13A, and 13B, the gripper arms 152 and 154 of the gripper mechanism 150 are configured to allow the new tooling 110 to be towed, picked up, and positioned together with the squeegee blade assembly, for example, by the print head assembly 20.

[0045] An exemplary sequence for replacing items within a stencil printer is described below. Removal and replacement of items in a specific sequence is preferred to efficiently utilize the stencil printer's capabilities for automated replacement of stencils, squeegee blades, and work holder tooling. The sequence order has been developed within and around the physical constraints of the stencil printer. It should be understood that the sequences for replacing items within a stencil printer disclosed herein can also be adapted to any custom needs of the stencil printer or mobile cart.

[0046] The printhead and printhead gantry are used to transport and precisely position the tooling tray. The tooling tray is configured to hold the squeegee blade assembly and tooling used in the stencil printer. When the printhead and printhead gantry position the tooling tray in the stencil printer using printer imaging alignment, the squeegee blade assembly and tooling may be transported to or from the tooling tray using the printer printhead gantry. In one embodiment, an imaging system, e.g., imaging system 30, may be used to determine the location of the tooling tray by taking an image of the tooling tray and using printer imaging alignment software associated with a controller, e.g., controller 14.

[0047] Changing the replaceable items in a complete stencil printer requires removing the stencil, unloading the squeegee blade assembly and tooling from the stencil printer, followed by loading a new squeegee blade assembly and tooling, and inserting a new stencil into the printer. In one embodiment, a method for defining the sequence of items to be replaced in a stencil printer, a sequence for changing the tooling of an automated printer, is as follows: The existing stencil is removed from the stencil printer.

[0048] The tooling tray is inserted into the stencil printer using the print head and print head gantry. The tooling tray includes new tooling and a new squeegee blade assembly. The tooling tray may be handed to the stencil printer by an operator or by a mobile cart. The position of the tooling tray is verified by using imaging alignment verification software associated with the controller. As described above, an imaging system may be employed to capture an image of the tooling tray and send the image to the controller for verification. Furthermore, the imaging system may be used to position the tooling tray so that it is precisely aligned with devices on the print head, such as tooling pins associated with the print head.

[0049] After determining the location of the tooling tray, the squeegee blade assembly is removed from the print head of the stencil printer and placed in the tooling tray. Next, the tooling is removed from the stencil printer. Specifically, the tooling is picked up and placed in the tooling tray using the tooling pins associated with the print head and print head gantry. Once the squeegee blade assembly and tooling are placed in the tooling tray, the process of loading a new squeegee blade assembly and new tooling may begin.

[0050] As described above, the tooling tray contains a new squeegee blade assembly and new tooling, intended to replace the used squeegee blade assembly and used tooling previously removed from the stencil printer. Next, the new squeegee blade assembly is picked up and placed on the print head. Then, the new tooling is placed on the stencil printer's work holder table, for example, the support assembly 28, by using the tooling pins associated with the stencil printer's print head and print head gantry. After the new squeegee blade assembly and new tooling are installed, the tooling tray is removed from the stencil printer.

[0051] A new stencil is inserted into the stencil printer. At this point, the sequence for replacing items within the stencil printer is complete.

[0052] The movable cart may be configured to pass the stencil and tooling tray and remove them from the stencil printer. For example, in one embodiment, the stencil printer may be configured to move the stencil and tooling tray to a suitable position where the movable cart is configured to complete the removal. The stencil and / or tooling tray may be moved and positioned within the stencil printer by tooling pins associated with the print head and print head gantry. Specifically, the tooling pins may be used to engage with the stencil and / or tooling tray to move the stencil and / or tooling tray laterally within the stencil printer.

[0053] As used in this application, “automated” or “fully automated” switching refers to the exchange or replenishment of items without human intervention.

[0054] As used in this application, “partially automated” switching describes the exchange or replenishment of items with some or limited human intervention.

[0055] As used in this application, "transport" or "transporting" describes moving an item from one location to another using manual or mechanical means.

[0056] As used in this application, "install" or "installing" describes the process of placing an item in a position where it is ready for use.

[0057] As described above, the movable cart can be used to replace other items within the stencil printer. For example, the stencil wiper assembly includes consumables such as paper and solvent that can be automatically replaced by the movable cart.

[0058] The concepts disclosed herein may be applied to other types of equipment used to manufacture electronic circuit boards, including dispensers, pick-and-place machines, reflow ovens, wave soldering machines, selective soldering machines, and inspection stations. For example, a concept relating to paste cartridge replacement can be applied to a dispenser used to dispense viscous materials. In another example, a concept relating to tooling replacement can be applied to a dispenser and a pick-and-place machine used to mount electronic components onto an electronic circuit board. In yet another example, a concept relating to item replacement can be applied to solder replacement in wave soldering machines and selective soldering machines, and to product cleaning in a cleaning station.

[0059] Thus, while several aspects of at least one embodiment have been described, it will be understood that various variations, modifications, and improvements will be readily conceivable to those skilled in the art. Such variations, modifications, and improvements are intended to be part of and within the scope of this disclosure. Accordingly, the above description and drawings are merely illustrative. [Configuration 1] A dual-function tooling tray for stencil printers, A perimeter frame having four sides, A first frame member separated from the first side of the surrounding frame, A second frame member spaced apart from the second side of the surrounding frame, wherein the first side and the second side of the surrounding frame are parallel to each other; A third frame member extending between the first frame member and the second frame member and fixed to the first frame member and the second frame member, configured to support at least one squeegee blade assembly, A first support portion fixed to the first frame member and a second support portion fixed to the second frame member, the first support portion and the second support portion configured to support the tooling plate together, A third support portion fixed to the first frame member and a fourth support portion fixed to the second frame member, the third support portion and the fourth support portion configured to support the tooling plate together, A touring tray equipped with [features / equipment]. [Configuration 2] The tooling tray according to configuration 1, wherein the first support portion and the second support portion are positioned adjacent to the third side portion of the surrounding frame, and the third support portion and the fourth support portion are positioned adjacent to the fourth side portion of the surrounding frame. [Configuration 3] The tooling tray according to configuration 2, wherein the first support portion and the second support portion are separated from each other by a predetermined distance sufficient to support the tooling plate. [Structure 4] The tooling tray according to configuration 3, wherein the third support portion and the fourth support portion are separated from each other by a predetermined distance sufficient to support the tooling plate. [Composition 5] The tooling tray according to configuration 1, further comprising a first support member, the first support member being connected at one end to the first side of the surrounding frame and at the opposite end to the first frame member. [Composition 6] The tooling tray according to configuration 5, further comprising a second support member, the second support member being connected at one end to the second side of the surrounding frame and at the opposite end to the second frame member. [Composition 7] The tooling tray according to Configuration 1, wherein the first support portion, the second support portion, the third support portion, and the fourth support portion each include a feature portion configured to engage with a fitting feature portion associated with the tooling plate for supporting the tooling plate. [Structure 8] The tooling tray according to configuration 7, wherein the feature portion is a pin, and the fitting feature portion is an opening sized to receive the pin. [Composition 9] The tooling tray according to configuration 7, wherein at least one of the first support portion and the second support portion, and at least one of the third support portion and the fourth support portion, each includes a fiducial configured to be detected by an imaging system. [Configuration 10] The tooling tray according to configuration 1, wherein the third frame member is perpendicular to the first frame member and the second frame member. [Composition 11] The tooling tray according to configuration 1, wherein the third frame member includes at least one squeegee blade assembly support structure. [Composition 12] The tooling tray according to configuration 11, wherein the third frame member further includes a drip tray. [Composition 13] The drip tray is fixed to the bottom surface of the third frame member, as described in configuration 12. [Composition 14] The tooling tray according to configuration 1, wherein the surrounding frame is configured to be engaged by a gripper associated with the print head of a stencil printer. [Composition 15] A method for replacing items in a stencil printer, The present invention provides a tooling tray that includes a new tooling support and a new squeegee blade assembly support, and a used tooling support and a used squeegee blade assembly support, wherein the tooling tray includes a new tooling plate on the new tooling support and a new squeegee blade assembly on the new squeegee blade assembly support. Removing the used squeegee blade from the print head of the stencil printer, Positioning the used squeegee blade assembly on the used squeegee blade assembly support portion of the tooling tray, Removing the used tooling plate from the support assembly of the stencil printer, Positioning the used tooling plate on the used tooling support portion of the tooling tray, Removing the new squeegee blade assembly from the tooling tray, Installing the new squeegee blade assembly onto the print head of the stencil printer, Removing the new touring plate from the touring tray, The new tooling plate is installed on the support assembly of the stencil printer, Methods that include... [Composition 16] The method of configuration 15, further comprising passing the tooling tray to the stencil printer and moving the tooling tray within the stencil printer. [Composition 17] The method according to configuration 16, wherein the tooling tray is moved by a gripper mechanism associated with the print head of the stencil printer. [Composition 18] The method according to configuration 16, wherein passing the tooling tray to the stencil printer includes moving the tooling tray by a movable cart employed for passing the stencil and tooling tray and for removing the stencil and tooling tray from the stencil printer. [Composition 19] The method according to configuration 15, further comprising verifying the position of the tooling tray. [Configuration 20] The method according to configuration 19, wherein verifying the position of the tooling tray includes capturing an image of the tooling tray together with a fiducial provided on the tooling tray.

Claims

1. A dual-function tooling tray for stencil printers, A perimeter frame having four sides, A first frame member separated from the first side of the surrounding frame, A second frame member spaced apart from the second side of the surrounding frame, wherein the first side and the second side of the surrounding frame are parallel to each other; A third frame member extending between the first frame member and the second frame member and fixed to the first frame member and the second frame member, the third frame member being configured to support at least one squeegee blade assembly, A first support portion fixed to the first frame member and a second support portion fixed to the second frame member, the first support portion and the second support portion configured to support the tooling plate together, A third support portion fixed to the first frame member and a fourth support portion fixed to the second frame member, the third support portion and the fourth support portion configured to support the tooling plate together, A touring tray equipped with [features / equipment].

2. The tooling tray according to claim 1, wherein the first support portion and the second support portion are positioned adjacent to the third side portion of the surrounding frame, and the third support portion and the fourth support portion are positioned adjacent to the fourth side portion of the surrounding frame.

3. The tooling tray according to claim 2, wherein the first support portion and the second support portion are separated from each other by a predetermined distance sufficient to support the tooling plate.

4. The tooling tray according to claim 3, wherein the third support portion and the fourth support portion are separated from each other by a predetermined distance sufficient to support the tooling plate.

5. The tooling tray according to claim 1, further comprising a first support member, the first support member being connected at one end to the first side of the surrounding frame and at the opposite end to the first frame member.

6. The tooling tray according to claim 5, further comprising a second support member, the second support member being connected at one end to the second side of the surrounding frame and at the opposite end to the second frame member.

7. The tooling tray according to claim 1, wherein the first support portion, the second support portion, the third support portion, and the fourth support portion each include a feature portion configured to engage with a fitting feature portion associated with the tooling plate for supporting the tooling plate.

8. The tooling tray according to claim 7, wherein the feature portion is a pin, and the fitting feature portion is an opening sized to receive the pin.

9. The tooling tray according to claim 7, wherein at least one of the first support portion and the second support portion, and at least one of the third support portion and the fourth support portion, each includes a fiducial configured to be detected by an imaging system.

10. The tooling tray according to claim 1, wherein the third frame member is perpendicular to the first frame member and the second frame member.

11. The tooling tray according to claim 1, wherein the third frame member includes at least one squeegee blade assembly support structure.

12. The tooling tray according to claim 11, wherein the third frame member further includes a drip tray.

13. The tooling tray according to claim 12, wherein the drip tray is fixed to the bottom surface of the third frame member.

14. The tooling tray according to claim 1, wherein the surrounding frame is configured to be engaged by a gripper associated with the print head of a stencil printer.

Images