Tilt and Rotate Dispenser with Motion Control - Patent application

Abstract

The feeding system comprises a frame, a support coupled to the frame, a feeding unit configured to feed a viscous material, and a gantry assembly coupled to the frame. The gantry assembly comprises a gantry configured to support the feeding unit and move the feeding unit in x-, y-, and z-axis directions, and a tilt-and-rotate subassembly configured to tilt and rotate the feeding unit. The feeding system further comprises a controller configured to control the feeding unit and the gantry assembly to perform a feeding operation relative to the electronic substrate. The controller is configured to simultaneously coordinate the movement of the gantry assembly and the tilt-and-rotate subassembly to position and point a nozzle of the feeding unit at a predetermined distance and orientation from the electronic substrate while feeding material along a three-dimensional path.

Description

[Technical field]

[0001] Background of the disclosure 1. Field of disclosure The present disclosure relates generally to an apparatus and method for dispensing a viscous material onto a substrate, such as a printed circuit board, and more particularly to a method and apparatus for dispensing material onto a substrate using a mechanism configured to tilt and rotate a dispensing unit. [Background technology]

[0002] 2.Related technology review There are several types of dispensing systems that are used to dispense precise amounts of liquid or paste for various applications. One such application is the assembly of integrated circuit chips and other electronic components onto the substrate of a circuit board. In this application, automated dispensing systems are used to dispense dots of liquid epoxy or solder paste, or some other related material, onto a printed circuit board. Automated dispensing systems are also used to dispense lines of underfill and encapsulant materials that can be used to mechanically secure components to the printed circuit board. Exemplary dispensing systems described above include those manufactured and marketed by Illinois Tool Works Electronic Assembly Equipment (ITWEAE), Inc., having a place of business in Hopkinton, Massachusetts.

[0003] In a typical dispensing system, a dispensing unit is mounted on a moving assembly or gantry for moving the dispensing unit along three mutually orthogonal axes (x-axis, y-axis, and z-axis) using servo motors controlled by a computer system or controller. To dispense a dot of liquid to a desired location on a printed circuit board or other substrate, the dispensing unit is moved along coplanar horizontal x-axis and y-axis directions until the dispensing unit is positioned above the desired location. The dispensing unit is then lowered along a vertical z-axis direction oriented vertically until the dispensing unit and dispensing system nozzle / needle are at the appropriate dispensing height above the substrate. The dispensing unit dispenses a dot of liquid, then is raised along the z-axis, moved along the x-axis and y-axis to a new location, and lowered along the z-axis to dispense the next dot of liquid. For applications such as encapsulating or dispensing underfill as described above, the dispensing unit is typically controlled to dispense a line of material as the dispensing unit is moved in the x-axis and y-axis along the desired path of the line. For some types of dispensing units, such as injection pumps, z-axis movement before and after the dispensing action may not be required.

[0004] Better control of the feed unit is desired to precisely place feed material closer to corners where the component edge meets the substrate, or other spaces / orientations requiring such movement. Summary of the Invention

[0005] Disclosure Summary One aspect of the present disclosure relates to a feeding system for feeding a viscous material onto an electronic substrate. In one embodiment, the feeding system includes a frame, a support coupled to the frame configured to receive and support the electronic substrate during a feeding operation, and a feeding unit configured to feed a viscous material, the feeding unit having a nozzle. The feeding system further includes a gantry assembly coupled to the frame, the gantry assembly including a gantry configured to support the feeding unit and move the feeding unit in x-, y-, and z-axis directions, and a tilt-and-rotate subassembly configured to tilt and rotate the feeding unit. The feeding system further includes a controller configured to control the feeding unit and the gantry assembly to perform a feeding operation on the electronic substrate. The controller is configured to simultaneously coordinate the movement of the gantry assembly and the tilt-and-rotate subassembly to position and orient the nozzle of the feeding unit at a predetermined distance and direction from the electronic substrate while feeding material along a three-dimensional path.

[0006] An embodiment of the feeding system may further include positioning the nozzle at a predetermined distance of up to 5.0 mm from the electronic board. The controller may be further configured to maintain the nozzle of the feeding unit at a predetermined angle relative to a horizontal plane of the electronic board. The predetermined angle may be between 0 and 90 degrees. The controller may be further configured to move the nozzle of the feeding unit at a constant speed relative to the package. The constant speed may be up to 1000 mm / sec. The controller may be further configured to feed material from the nozzle of the feeding unit at a flow rate configured to deposit a desired amount or density of material on the electronic board. The flow rate may be up to 2000 mg / sec. The tilt-and-rotate subassembly may be configured to tilt the feeding unit up to 360 degrees and rotate the feeding unit up to 360 degrees. The feeding system may further comprise a vision system coupled to one of the frame and the gantry assembly to capture at least one image of the electronic board. The controller may be further configured to control the vision system. The controller may be further configured to calibrate a feed position of a nozzle of the feed unit relative to the vision system by feeding onto the electronics board mounted on the support. The controller may include or have access to a database having a table of nozzle orientations relative to a vision system. The controller may be configured to calibrate the nozzle orientation based in part on interpolation of known positions and orientations.

[0007] Another aspect of the present disclosure relates to a method of dispensing a viscous material onto an electronic substrate, in one embodiment, the method includes delivering an electronic substrate to a dispensing location, capturing at least one image of the electronic substrate, analyzing the at least one image of the electronic substrate to determine a position of the electronic substrate, and performing a dispensing operation by moving, tilting and rotating a dispensing unit coupled to a gantry configured to support the dispensing unit and move the dispensing unit in x-, y- and z-axis directions, and a tilt and rotate subassembly configured to tilt and rotate the dispensing unit. Performing the dispensing operation includes simultaneously coordinating the movements of the gantry assembly and the tilt and rotate subassembly to position and orient a nozzle of the dispensing unit at a predetermined distance and direction from the electronic substrate while dispensing material along a three-dimensional path.

[0008] Embodiments of the method may further include maintaining the nozzle of the supply unit at a predetermined angle relative to a horizontal plane of the electronic board. Performing the dispensing operation may include moving the nozzle of the supply unit at a constant speed relative to the package. Performing the dispensing operation may include dispensing material from the nozzle of the supply unit at a flow rate configured to deposit a desired amount or density of material on the electronic board. The method may further include calibrating a dispensing position of the nozzle of the supply unit relative to the vision system of the dispenser by dispensing onto the electronic board mounted on the support. The controller may include or have access to a database having a table of nozzle orientations relative to a vision system.

[0009] BRIEF DESCRIPTION OF THE DRAWINGS Various aspects of at least one embodiment are discussed below with reference to the accompanying drawings, which are not intended to be drawn to scale. The drawings are included to provide illustration and further understanding of the various aspects and embodiments, and are incorporated in and constitute a part of this specification, but are not intended as a definition of the limitations of any particular embodiment. The drawings, together with the remainder of the specification, serve to explain the principles and operation of the described and claimed aspects and embodiments. In the drawings, each identical or nearly identical component shown in the various figures is represented by a like reference numeral. For clarity, not every component is labeled in every figure. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a supply system. [Diagram 2] FIG. 2 is a perspective view of the dispensing system with the packaging removed to disclose the dispensing system configured to operate a single dispensing unit. [Diagram 3] FIG. 3 is a perspective view of the supply system shown in FIG. 2 with the supply unit removed. [Figure 4] FIG. 2 is an enlarged perspective view of the supply system. [Diagram 5] FIG. 5 is an enlarged perspective view of the supply system shown in FIG. 4, with the supply unit separated from the remaining components of the supply system. [Figure 6] FIG. 2 is a cross-sectional view of the supply system. [Figure 7A] FIG. 1 illustrates an exemplary package mounted on an electronic substrate. [Figure 7B] FIG. 1 illustrates an exemplary package mounted on an electronic substrate. [Figure 8] FIG. 1 illustrates an example computer system in which various aspects of the present disclosure may be practiced. [Figure 9] FIG. 1 illustrates an example storage system in which various aspects of the present disclosure may be implemented. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Detailed Description of the Disclosure Various embodiments of the present disclosure relate to a viscous material supply system, a device including the supply system, and a technique for supplying material onto an electronic substrate by a supply system that includes a supply unit configured to tilt and rotate to supply the material onto the electronic substrate.

[0012] For purposes of illustration only and not limitation of generality, the present disclosure will now be described in detail with reference to the accompanying drawings. The present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The principles described in the present disclosure can be used in other embodiments and can be practiced or carried out in various ways. Additionally, the phraseology and terminology used in the present disclosure are for the purpose of illustration and should not be considered as limiting. Any reference to an example, embodiment, component, element or operation of a system or method referred to in the present disclosure as singular can also encompass embodiments including the plural, and any reference to any embodiment, component, element or operation in the present disclosure as plural can also encompass embodiments including only the singular. References in the singular or plural are not intended to limit the systems or methods disclosed in the present disclosure, their components, operations or elements. The use of the terms "including", "comprising", "having", "containing", "with" and variations thereof in the present disclosure are meant to encompass the preceding described items, as well as equivalents and additional items. References to "or" may be construed as inclusive such that any term described with "or" may include any of one, one or more, and all of the described terms. In addition, in the event of an inconsistency in the usage of a term between this document and any document incorporated by reference herein, the usage of the term in the document incorporated herein is supplementary to the usage in this document, and in the event of the inconsistency resulting in a conflict, the usage of the term in this document shall prevail.

[0013] FIG. 1 illustrates generally a dispensing system, generally designated 10, according to one embodiment of the present disclosure. The dispensing system 10 is used to dispense a viscous material (e.g., adhesive, encapsulant, epoxy, solder paste, underfill material, etc.) or a semi-viscous material (e.g., solder flux, etc.) onto an electronic substrate 12, such as a printed circuit board or a semiconductor wafer. The dispensing system 10 may alternatively be used to apply gasket material for automobiles, or in certain medical fields, or in other applications, such as to apply conductive inks. It should be understood that references to viscous or semi-viscous materials as used in this disclosure are intended to be exemplary and non-limiting. In one embodiment, the dispensing system 10 includes a first dispensing unit and a second dispensing unit, generally designated 14 and 16, respectively, and a controller 18 that controls the operation of the dispensing system. It should be understood that the dispensing units may also be referred to as dispensing pumps and / or dispensing heads in this disclosure. Although two supply units are shown, it should be understood that the array of supply units can use a single or multiple supply units.

[0014] The feeding system 10 may also include a frame 20 having a base or support 22 for supporting the electronic board 12, a feeding unit gantry 24 movably coupled to the frame 20 for supporting and moving the feeding units 14, 16, and a weight measuring device or scale 26 for weighing the dispensed amount of viscous material and providing weight data to the controller 18, e.g., as part of a calibration procedure. Other transport mechanisms such as a conveyor system (not shown) or a walking beam may also be used in the feeding system 10 to control the loading and unloading of the electronic boards from the feeding system. The gantry 24 may be moved using a motor under the control of the controller 18 to position the feeding units 14, 16 at predetermined positions above the electronic boards. The feeding system 10 may include a display unit 28 connected to the controller 18 for displaying various information to an operator. An optional second controller may be provided for controlling the feeding units. Each feeding unit 14, 16 may also be configured to detect the height at which the feeding unit is located above the electronic board 12 or above a feature mounted on the electronic board using a z-axis sensor. The z-axis sensor is coupled to the controller 18 and relays information obtained by the sensor to the controller.

[0015] As described above, before performing a feeding operation, the substrate, e.g., a printed circuit board, must be aligned or otherwise positioned relative to a feeding unit of the feeding system. The feeding system further comprises a vision system 30, which in one embodiment is coupled to a vision system gantry 32, which is movably coupled to the frame 20 for supporting and moving the vision system. In another embodiment, the vision system 30 may be provided on the feeding unit gantry 24. As described above, the vision system 30 is utilized to verify the location of landmarks or components, known as fiducials, on the electronic board. Once located, the controller can be programmed to manipulate the movement of one or more of the feeding units 14, 16 to feed material onto the electronic board.

[0016] The systems and methods of the present disclosure relate to dispensing material onto electronic boards, such as printed circuit boards. The description of the systems and methods provided in this disclosure refers to an exemplary electronic board 12 (e.g., printed circuit board) supported on a support 22 of a dispensing system 10. In one embodiment, the dispensing operation is controlled by a controller 18, which may include a computer system configured to control the material dispensing unit. In another embodiment, the controller 18 may be operated by an operator. The controller 18 is configured to manipulate the movement of the vision system gantry 32 to move the vision system to capture one or more images of the electronic board 12. The controller 18 is further configured to manipulate the movement of the dispensing unit gantry 24 to move the dispensing units 14, 16 to perform the dispensing operation.

[0017] An embodiment of the present disclosure relates to a strain wave gear drive assembly configured to tilt and rotate a feed unit of a feeding system to provide alternative and comparable means to simultaneously and precisely feed one or more electronic boards, or two or more patterns associated with a single electronic board. The methods disclosed in this disclosure further support the use of various types of feed units, including but not limited to auger, piston, and jet pumps.

[0018] 2 and 3, a feed system is generally indicated at 40. As shown, the feed system 40 includes a frame 42 configured to support the major subassemblies of the feed system. The feed system 40 further includes a gantry system, generally indicated at 44, configured to move in the x-axis and y-axis directions. The feed system 40 further includes a feed unit assembly, generally indicated at 46, supported by the gantry system 44. FIG. 2 illustrates the feed system 40 including the feed unit assembly 46, and FIG. 3 illustrates the feed system 40 with the feed unit assembly removed. A conveyor system (not shown) may be used within the feed system 40 to control the movement of a substrate, e.g., electronic substrate 12, into and out of the support 50 of the feed system. The gantry system 44 may be moved in the x-axis and y-axis directions using motors under the control of a controller, similar to the controller 18 of the feed system 10, to position the feed unit assembly 46 at a predetermined location on the electronic substrate.

[0019] In one embodiment, as shown in FIGS. 2 and 3, the gantry system 44 can be configured to include a left side rail 52, a right side rail 54, and a beam 56 extending between the two side rails. The beam 56 is configured to move in a y-axis direction along the side rails 52, 54 to effect y-axis movement of the feeding unit assembly 46. The gantry system 44 further includes a carriage 58 coupled to the beam 56 and configured to move along the length of the beam to effect x-axis movement of the feeding unit assembly 46. Specifically, the carriage 58 supports the feeding unit assembly 46 and is configured to move in an x-axis direction along the length of the beam to move the feeding unit 48 above a desired location of the electronic board 12 positioned on the support 50 of the feeding system 40. In certain embodiments, movement of the gantry system 44 (i.e., movement of the beam 56 and the carriage 58) in the xy plane can be accomplished by employing ball screw mechanisms driven by respective motors, as is well known in the art.

[0020] In one embodiment, the exemplary delivery system described herein may embody the Camalot™ delivery system sold by ITWEAE, Inc. of Hopkinton, Massachusetts.

[0021] The feed unit assembly 46 is configured to move the feed unit 48 in the z-axis direction by a z-axis drive mechanism 60 shown in FIG. 2. The z-axis movement can be determined by measuring the distance between the tip of a nozzle, sometimes referred to as a needle (not shown), of the feed unit 48 and the electronic board 12. When moving, the feed unit 48 can be positioned at a nominal clearance height above the electronic board 12. The clearance height can be maintained at a relatively consistent height above the electronic board 12 when moving from one feed position to another. Once at the predetermined feed position, the z-axis drive mechanism 60 lowers the feed unit 48 to the electronic board 12, thereby accomplishing the feeding of material onto the electronic board.

[0022] Still referring to FIG. 2 and FIG. 3, the supply unit 48 moves above the electronic board 12 so that the supply unit performs the supply operation. However, before supplying, the position of the electronic board 12 relative to the supply unit 48 is determined so that accurate supplying can be performed. Specifically, in one embodiment, the carriage 58 can be configured with an optical element or camera designed to acquire an image of the electronic board 12. Although the camera is shown mounted on the carriage 58, it should be understood that it can be separately mounted on the beam 56 or an independent gantry. In this disclosure, the camera can be referred to as a "vision system" or an "imaging system". To align the electronic board 12 with the supply unit 48 and the gantry system 44, an image of at least two fiducials provided on the electronic board 12 is acquired by the camera. If the electronic board 12 is out of position, the gantry system 44 can be manipulated to take into account the actual position of the electronic board. In one embodiment, the camera can be calibrated to determine a camera-to-needle offset distance for the supply unit 48. In another embodiment, visual alignment and clearance height sensing can be accomplished using a laser or other calibrated distance measuring device.

[0023] A feeding system typically has a feeding unit that is oriented vertically and thus perpendicular to the substrate that is fixed horizontally. In some applications, it is advantageous to tilt the feeding unit away from the vertical to deposit the material being fed in locations that are otherwise inaccessible from the vertical orientation. When the tilting feeding unit is articulated to various desired orientations, it may be advantageous to change not only the angle of the feeding unit from the vertical, but also the direction in which the feeding unit is tilted, in some cases depositing material on the bottom edge of the part along two or more sides.

[0024] As will be appreciated by those familiar with moving structures, the mechanisms used to tilt and rotate the feed unit 48 add mass and reduce structural stiffness since the additional mechanisms introduce additional compliance. As the supported mass increases and the stiffness of the structure decreases, the natural frequency of the assembly decreases. It is therefore up to the designer to provide the necessary degrees of freedom with the stiffest possible structure, with a minimal increase in mass.

[0025] An embodiment of the presently disclosed feed system 40 achieves this goal by incorporating a very compact, highly integrated rotary actuator with a motor, strain-wave harmonic reduction gear box, and high stiffness rotary cross-roller bearings, such as those available from Harmonic Drive, Inc., Beverly, Massachusetts. The high degree of integration in a wave gear box actuator helps minimize the increase in mass and compliance. Wave gear boxes have the added benefit of very low backlash. The integrated motor, bearing, and gear box assembly also helps minimize the number of parts that must be purchased, assembled, and tested.

[0026] 4 and 5, the feed unit assembly 46 includes a drive assembly configured to support the feed unit 48. The feed unit 48 is shown in an operating position in FIG. 4 and in a pre-operating position in FIG. 5 in which the feed unit is spaced apart from the components of the feed unit assembly configured to support the feed unit. As shown, the feed unit assembly 46 includes a support bracket 62 having an L-shaped configuration. A first portion 64 of the support bracket is fixed to the z-axis drive mechanism 60 of the carriage 58, and a second portion 66 extends vertically from the first portion. The feed unit assembly 46 further includes a movable bracket 68 that is rotatably coupled to the support bracket 62 at the second portion 66 of the support bracket by a first strain wave gear system 70. In the illustrated embodiment, the movable bracket 68 is configured to rotate relative to the support bracket 62 about a generally vertical axis A.

[0027] The movable bracket 68 includes a second strain wave gear system 72 configured to support the feed unit 48. As shown, the second strain wave gear system 72 includes a mounting plate 74 configured to receive and support the feed unit 48 when the feed unit is in an operating position. The second strain wave gear system 72 is configured to rotate and tilt the feed unit 48 to a desired position during a feed operation about an axis B that is generally perpendicular to axis A. In one embodiment, the first strain wave gear system 70 is configured similarly, if not identically, to the second strain wave gear system 72.

[0028] It should be understood that the orientation of the moveable bracket 68 relative to the support bracket 62 about axis A, and the orientation of the supply unit 48 relative to the moveable bracket, can be varied to suit a particular application. For example, the moveable bracket 68 can be rotatably coupled to the support bracket 62 about a generally horizontal axis, and the supply unit can be rotatably coupled to the moveable bracket about a generally vertical axis.

[0029] 6 illustrates a cross-sectional view of the feed unit assembly 46 showing the first strain wave gear system 70 and the second strain wave gear system 72. The moveable bracket 68 is configured to rotate a maximum of 360 degrees, i.e., from 0 to 360 degrees, relative to the support bracket 62. Similarly, the feed unit 48 is configured to rotate a maximum of 360 degrees, i.e., from 0 to 360 degrees, relative to the moveable bracket 68. Thus, the amount of rotation and tilt of the feed head 48 is unlimited.

[0030] In one embodiment, a controller or control system, such as the controller 18, can be configured with a suitable operating system with application specific software that controls the operation of the feeding system 40. In certain embodiments, an operator of the feeding system 40 can operate the feeding system through the control system either manually by operating a keyboard and mouse with which the control system is provided, or automatically by preprogramming the control system via the keyboard and mouse. The controller is further configured to analyze at least one image of the electronic board 12 to determine the position of the electronic board in the x-axis, y-axis and θ-axis directions, calculate a rotation angle of the electronic board, and rotate the feeding unit 48 to match the angle of the electronic board when performing the feeding operation.

[0031] In operation, when depositing material onto a substrate, such as an electronic board, a feed unit 48 of the feed unit assembly 46 is positioned adjacent to the electronic substrate by operating the gantry system. A controller controls the automated movement of the feed unit 48 by operating the gantry system 44 to feed material onto the electronic substrate 12 by rotating the feed unit about the A and B axes. The controller controls the movement (linear and rotational) of the feed unit of the feed unit assembly 46 by controlling the operation of the gantry system 44 and the drive assembly.

[0032] Thus, it can be seen that the moveable bracket 68 is configured to rotate a full 360 degrees relative to the support bracket 62, and the feed unit 48 is configured to rotate a full 360 degrees relative to the moveable bracket. This allows the feed unit 48 to deposit material in hard to reach locations on the electronic board 12. The feed system 40 disclosed in this disclosure employs a unique combination of drive assemblies that control the direction of the feed unit 48, with the benefit of improving the speed and accuracy of the feed application.

[0033] Motion Control As mentioned above, the dispenser of the disclosed embodiments may include a feed unit including, but not limited to, an auger, a piston, and a jet feed unit. A controller of the feed system, e.g., controller 18 of feed system 10, is configured to perform a feed operation on the electronic board. In particular, the controller is configured to control the movement of a vision system and a vision system gantry, e.g., vision system 30 and vision system gantry 32, to capture images of the electronic board, e.g., electronic board 12, and any components or packages mounted thereon. With reference to FIGS. 7A and 7B, an exemplary electronic board 80 has a package 82 mounted thereon. The package 82 may include any type of electronic component, such as an integrated circuit. Also shown is a nozzle 90 of a feed unit, e.g., feed unit 48, positioned relative to an intersection or connection end point of the package 82 and the electronic board 80.

[0034] As discussed above, it is desirable to deposit material on electronic substrate 80 around the periphery of package 82, and conventional vertical dispensing is inadequate to perform this function. However, in the embodiment dispensing systems disclosed in this disclosure, including dispensing system 40, the dispensing units can be tilted and rotated to position nozzles 90 of the dispensing units to optimize dispensing action around the periphery of package 82. Additionally, the dispensing systems are configured to dispense material around packages or other components of various shapes and sizes.

[0035] Once the image is acquired, the controller is configured to control movement of the gantry, the first and second strain wave gear systems, and actuation of the feed unit to feed material around the packages 82 mounted on the electronic board 80. The speed of movement of the feed unit nozzle 90 is determined by the controller to, in part, achieve a desired amount or density of material dispensed on the electronic board.

[0036] In one embodiment, the tip of the nozzle 90 can be controlled to achieve or otherwise maintain a predetermined distance 100 from the intersection of the package 82 and the electronic board 80 while dispensing material around the package. Specifically, the controller is configured to control the feed unit gantry, e.g., gantry system 44, and the tilt-and-rotate subassemblies, e.g., first strain wave gear system 70 and second strain wave gear system 72, to position the tip of the nozzle 90 such that the tip of the nozzle 90 maintains a predetermined distance 100 from the edge of the package 82 at the intersection of the package 82 and the electronic board 80. As shown, the feed unit nozzle 90 is positioned at a predetermined angle by the second strain wave gear system. The tip of the feed unit nozzle 90 can be positioned by rotating the feed unit by controlling the first strain wave gear system by the controller. Such an arrangement allows the feed unit to be rotated while moving with the gantry, such that the tip of the feed unit nozzle maintains a predetermined distance 100 from the intersection as it transitions from a straight side of the package 82, around the package corner, and to a straight vertical side of the package. In one particular embodiment, for example, the predetermined distance 100 is up to 5.0 mm. In another example, the predetermined distance 100 is between 0.025 mm and 1.0 mm.

[0037] In one embodiment, the nozzle 90 can be controlled to place or maintain the nozzle of the supply unit at a predetermined angle 102 relative to the horizontal plane of the electronic board 80. As described above, the angle 102 of the nozzle of the supply unit 90 can be optimized to position the tip of the nozzle 90 as close as possible to the intersection of the package 82 and the electronic board 80. Although a perpendicular angle (90 degrees) is shown between the package and the electronic board, the package may be shaped to extend at any angle from the electronic board. The second strain wave gear system can be controlled by a controller to reach the predetermined angle 102. For example, the predetermined angle 102 can be between 0 and 90 degrees. In another example, the predetermined angle 102 can be about 45 degrees.

[0038] In one embodiment, the nozzle 90 can be controlled by the controller to have or move the nozzle of the supply unit at a constant speed relative to the package 82. As described above, the controller is configured to operate the gantry, the first strain wave gear system, and the second strain wave gear system to position the tip of the nozzle of the supply unit 90 at a predetermined distance 100 from the intersection of the package 82 and the electronic board 80. The controller is further configured to operate the second strain wave gear system to position the nozzle of the supply unit 90 at a predetermined angle 102 to optimize the position of the tip of the nozzle. The controller is configured to move the supply unit to move the nozzle of the supply unit 90 at a constant speed, thereby helping to ensure that a desired amount or density of material is deposited on the electronic board 80 adjacent the package 82. The speed of the supply unit can be varied, but a constant speed is desired, especially during straight sections of the package. For example, the constant speed is up to 1000 mm / sec. In another example, the constant velocity is between 20 mm / sec and 200 mm / sec.

[0039] The spatial predetermined distance 100 of the nozzle 90 tip from the intersection of the package 82 and the electronic board 100, the predetermined angle 102 of the dispenser nozzle, and the speed of the dispenser unit together provide motion control for the dispenser unit. Control of the motion of the dispenser nozzle 90 tip is along the x-axis, y-axis, and rotational axis and is achieved by the gantry, the first wave harm gear system, and the second wave harm gear system using a controller. As described above, a vision system can be used to obtain an image of the location of the package 82, and the controller is configured to determine the path along which the dispenser nozzle 90 dispenses material around the package. The controller provides instructions to the gantry, the first wave harm gear system, and the second wave harm gear system to control the motion of the dispenser unit during the dispensing operation.

[0040] As mentioned above, the size and shape of the packages 82 can embody a variety of shapes and sizes. The controller is configured to control the movement of the feeding unit by controlling the feeding system gantry, the first strain wave gear system, and the second strain wave gear system to perform feeding operations on the packages and components disposed on the electronic board 80.

[0041] In one embodiment, the controller is configured to simultaneously coordinate movement of a gantry assembly including a gantry and a tilt and rotate subassembly including a first strain wave gear system and a second strain wave gear system to position and orient a nozzle of the supply unit at a predetermined distance 100 and orientation 102 from the electronics board 80 while supplying material along a three-dimensional path.

[0042] Flow Control It should be appreciated that the amount of material deposited by the supply units of the supply system is determined not only by the control of the movement of the nozzle 90 of the supply unit, but also by the flow rate of the material dispensed by the supply unit. Specifically, with respect to flow rate, the pressure of the material in the supply unit and the size of the opening of the nozzle 90 of the supply unit determine the flow rate of the material from the supply unit. As described above, the gantry, the first wave gear system, and the second wave gear system are controlled by the controller to move the supply units such that the tip of the nozzle 90 of the supply unit is precisely positioned relative to the package. Based on the position of the tip of the nozzle 90 and the speed of the supply unit, the flow rate of the material is precisely controlled by the controller to dispense a desired amount or density of material around the package 82 on the electronic board 80.

[0043] As discussed above, the flow rate is determined in part by the viscosity of the material being dispensed, the pressure of the material in the nozzle 90, and the diameter of the nozzle through which the material is dispensed. The feed unit can be configured to control the pressure of the material in the nozzle 90. The pressure of the material can be controlled in the chamber of the feed unit by applying pressurized air within the chamber. In some embodiments, the size of the opening of the nozzle 90 of the feed unit can be selected to achieve a desired flow rate. It should be understood that as the material flows through the nozzle 90 and the diameter of the nozzle is reduced or increased, the flow rate of the material increases or decreases, respectively.

[0044] In one embodiment, the controller is configured to dispense material from the nozzle 90 of the dispensing unit at a flow rate configured to deposit a desired amount or density of material on the electronic substrate. The flow rate depends on the viscosity of the material being dispensed, the pressure of the material in the nozzle 90, and the diameter of the nozzle through which the material is dispensed. For example, the flow rate can be up to 2000 mg / sec. In another example, the flow rate can be between 0.05 mg / sec and 10 mg / sec.

[0045] Multiple Supply Units As discussed above, embodiments of the feeding system may include two or more feeding units that may be configured to simultaneously and accurately feed one or more electronic boards or two or more patterns associated with a single electronic board in a synchronous or asynchronous mode. Specifically, if the electronic boards are not properly aligned as determined by the controller, the feeding system may switch from a synchronous mode where two electronic boards or patterns are fed to an asynchronous mode where only one electronic board or pattern is fed. The methods disclosed in this disclosure further support the use of various types of feed pumps, including but not limited to auger, piston, and jet pumps.

[0046] An exemplary feeding operation for two substrates or substrate patterns can include delivering a first electronic substrate pattern to a feeding location, delivering a second electronic substrate pattern to a feeding location, aligning the first electronic substrate pattern with a first feeding unit, positioning the second feeding unit at a predetermined distance from the first feeding unit, feeding material from the first feeding unit to a desired location on the first electronic substrate pattern, and feeding material from the second feeding unit to a desired location on the second electronic substrate pattern. In a particular embodiment, feeding material from the first feeding unit can include lowering the first feeding unit toward the first electronic substrate pattern. Similarly, feeding material from the second feeding unit can include lowering the second feeding unit toward the second electronic substrate pattern.

[0047] Another exemplary feeding operation can comprise delivering a first electronic board pattern and a second electronic board pattern to respective feeding locations, positioning a first feeding unit above the first electronic board pattern, positioning a second feeding unit a predetermined distance from the first feeding unit, feeding material from the first feeding unit to a desired location on the first electronic board pattern, and feeding material from the second feeding unit to a desired location on the second electronic board pattern. Feeding the material from the first feeding unit includes lowering the first feeding unit toward the first electronic board pattern. Similarly, feeding the material from the second feeding unit includes lowering the second feeding unit toward the second electronic board pattern. In certain embodiments, the predetermined distance is determined by identifying a first reference point associated with the first electronic board pattern and a second reference point associated with the second electronic board pattern.

[0048] Yet another exemplary feeding operation for two substrates may comprise the steps of (1) calibrating the actual distance between each of the feeding units and the camera, (2) determining the actual location of the reference position on the substrate or substrates, (3) moving the first feeding unit to a first feeding position on the first substrate, (4) feeding to the first feeding position on the first substrate, (5) moving the second feeding unit to the first feeding position on the second substrate, which is a small and therefore rapidly performed movement, (6) feeding to the first feeding position on the second substrate, and (7) repeating steps (3) to (6) for each of the remaining feeding positions on the substrate. The above operations may be performed when feeding onto a single substrate having multiple patterns on the substrate.

[0049] It is further contemplated that when more than two supply units are used, this simultaneous feeding approach can be employed for every other substrate. For example, when three supply units are used, a first substrate, a third substrate, and a fifth substrate can be fed simultaneously by a first supply unit, a second supply unit, and a third supply unit, respectively. After feeding these substrates, the supply units can be moved such that feeding occurs for a second substrate, a fourth substrate, and a sixth substrate by the first supply unit, a second supply unit, and a third supply unit, respectively.

[0050] In an exemplary embodiment, a method of supplying material can include delivering an electronic substrate having at least two identical patterns to a supply location, acquiring data relating to the at least two patterns, determining whether the at least two patterns are sufficiently suitable for simultaneous supply based on the acquired data, to perform a simultaneous supply operation on the at least two patterns, and if the two patterns are sufficiently suitable for simultaneous supply, performing a simultaneous supply operation on the at least two patterns.

[0051] Supplying the material may include positioning a first supply unit above a first location of the first pattern and positioning a second supply unit above a first location of the second pattern. As described above, the second supply unit may be spaced a predetermined distance from the first supply unit. Specifically, the material may be supplied from the first supply unit and the second supply unit to the first location of each of the first pattern and the second pattern. When supplied, the first supply unit moves above the second location of the first pattern of the electronic substrate, and the second supply unit moves simultaneously above the second location of the second pattern of the electronic substrate. When moved, the material may be supplied from the first supply unit and the second supply unit to the second location of each of the first pattern and the second pattern.

[0052] In another exemplary embodiment, a method of supplying material may include: (1) identifying the positions of two or more locations on an electronic substrate; (2) determining whether the supply locations of the first pattern and the second pattern are sufficiently suitable for simultaneous supplying based on the identified positions to perform simultaneous supplying operations on the first pattern and the second pattern; (3) moving a first supply unit to a supply location on the first pattern and moving a second supply unit to a supply location on the second pattern, where the supply location of the first pattern corresponds to the supply location on the second pattern; (4) supplying the first supply location on the first pattern by the first supply unit and supplying the first supply location on the second pattern by the second supply unit; and (5) repeating steps (3) and (4) for each remaining supply location on the first pattern and the second pattern of the electronic substrate. As described above, the distance between the first supply unit and the camera and the distance between the second supply unit and the camera may be calibrated before performing the method.

[0053] In one embodiment, a one-time static adjustment for each substrate provided to the dispenser is performed by the vision system and controller identifying and calculating the distance from one portion of the substrate to another portion of the same substrate and any rotation of the substrate relative to the gantry system, and one-time adjustment of the second feed unit prior to simultaneous feeding. In another embodiment, an automatic adjustment mechanism can be used to perform dynamic adjustments while feeding is occurring. Thus, in instances where the two patterns are not well suited for simultaneous feeding, i.e., where the two substrates are not well suited for simultaneous feeding, the method includes simultaneously performing a first feeding operation by the first feed unit on the first pattern (or substrate) and a second feeding operation by the second feed unit on the second pattern (or substrate). This can be achieved by dynamically positioning the second feed unit by the automatic adjustment mechanism while continuing feeding by the first and second feed units.

[0054] The dispenser of the disclosed embodiments is capable of dispensing different patterns simultaneously. In such a manner, the gantry carrying the dispensing units and the automatic adjustment mechanism associated with the second dispensing unit (and / or the first dispensing unit) can be operated to dispense the different patterns simultaneously. In this manner, the lines dispensed by the first and second dispensing units can be drawn synchronously.

[0055] Thus, for dispensers with multiple feed units, the distance and relative position of each of the multiple feed units can be configured to match the distance and relative spacing between each of the multiple substrates or components. After collecting and analyzing alignment information from the automated vision alignment system, a first feed unit of the multiple feed units is positioned above a first feed location on a first substrate or component. After performing a feed operation, the gantry can be operated to make any required x-axis and y-axis plane position adjustments that may be required to align a second feed unit of the multiple feed units above a corresponding first feed location of a second substrate or component of the multiple substrates or components. Since the distance and relative position between each of the multiple feed units is substantially similar, but not necessarily identical, to the distance and relative position between each of the multiple substrates or components, any such adjustments of the gantry are very slight and therefore performed quickly. Each of the remaining multiple feed units can be similarly used to feed material to the corresponding first feed locations of each of the remaining substrates or components, after which larger movements of the gantry in the x-axis and y-axis directions are required. However, if the number of substrates or components is greater than the number of feed units, it may be necessary to reposition the gantry to complete the feed operation for all of the substrates. The method is repeated to feed the second feed location and each of the subsequent feed locations. It should be understood that steps can be interchanged as may be required by throughput or process improvements.

[0056] As mentioned above, in one embodiment, the feed units can be mounted on separate z-axis drive mechanisms. This configuration allows for independent operations to be performed, including but not limited to, feeding, cleaning (e.g., by an automatic needle / nozzle cleaner), sanitizing, and calibration (x-axis or y-axis position or z-axis position), where appropriate. However, it should be noted that the dispenser can be particularly suitable for non-contact feeding, such as by spilling or squirting material from a needle / nozzle. When configured for non-contact feeding, the feeding operations can be performed by two (or more) feed units mounted on a single z-axis drive mechanism.

[0057] One embodiment of the present disclosure relates to a method of feeding between synchronous and asynchronous modes, where a vision system is used to determine whether a substrate or substrates are sufficiently suitable for simultaneous feeding or whether a pattern or patterns are sufficiently suitable for simultaneous feeding, and if so, then a synchronous operating mode can be adopted to allow the substrates or patterns to be fed simultaneously by the feeding unit, however, if not, then an asynchronous operating mode can be adopted to allow the substrates or patterns to be fed automatically independently and asynchronously.

[0058] In some embodiments, the tilt and rotate subassembly is configured to tilt the supply unit up to 360 degrees and rotate the supply unit up to 360 degrees.

[0059] In some embodiments, the gantry further comprises a z-axis drive mechanism that provides movement of the feeding unit in the z-axis.

[0060] Computer Systems A controller (e.g., controller 18) as described above can be included in a computer system, which is described below in connection with Figures 8 and 9. In particular, Figure 8 illustrates an example computer system 104 that can be used to implement various aspects of the delivery systems (e.g., delivery system 40) described in this disclosure. Figure 9 illustrates an example storage system that can be used.

[0061] System 104 is merely one illustrative embodiment of a computer system suitable for implementing various aspects of the present invention. Such an illustrative embodiment is not intended to limit the scope of the present invention, since, for example, any of numerous other implementations of a system are possible and are intended to be within the scope of the present invention. For example, a virtual computing platform may be used. None of the claims set forth below are intended to be limited to any particular implementation of a system, unless such claim includes a limitation that explicitly recites a particular implementation.

[0062] Various embodiments according to the present invention can be implemented on one or more computer systems. These computer systems can be general-purpose computers, such as those based on Intel PENTIUM type processors, Motorola PowerPC, Sun UltraSPARC, Hewlett-Packard PA-RISC processors, or any other type of processor. It should be understood that one or more of any type of computer system can be used to partially or fully automate the integration of the described devices and systems with other systems and services according to various embodiments of the present invention. Furthermore, the software can be located on a single computer or distributed among multiple computers connected by a communications network. Such a communications network is utilized in certain embodiments to remotely control the delivery system described in this disclosure or to remotely transfer information to and from the delivery system described in this disclosure.

[0063] Various aspects of the present invention may be implemented as dedicated software executing on a general-purpose computer system 104 as shown in FIG. 8. The computer system 104 may include a processor 106 connected to one or more memory devices 116, such as a disk drive, memory, or other device for storing data. The memory 116 is typically used to store programs and data during operation of the computer system 104. The components of the computer system 104 may be coupled by an interconnection mechanism 114, which may include one or more buses (e.g., between components integrated within the same machine) and / or networks (e.g., between components present on separate, distinct machines). The interconnection mechanism 114 allows for the exchange of communications (e.g., data, instructions) between the system components of the system 104. The computer system 104 also includes one or more input devices 108, such as a keyboard, mouse, trackball, microphone, camera, touch screen, and one or more output devices 110, such as a feed unit, motor, camera, printing device, display unit, touch screen, and / or speaker. Additionally, computer system 104 may include one or more interfaces (not shown) that connect computer system 104 to a communications network (in addition to or as an alternative to interconnection mechanism 114).

[0064] The storage system 112, shown in more detail in Figure 9, typically includes a computer-readable and writable non-volatile recording medium 118 on which are stored signals defining programs to be executed by the processor 106 or information stored on or in the medium 118 to be processed by the programs. The medium 118 may be, for example, a disk or a flash memory. Typically, during operation, the processor 106 causes data to be read from the non-volatile recording medium 118 to another memory 120 that allows faster access to the information by the processor than the medium 118. This memory 120 is typically a volatile random access memory such as a dynamic random access memory (DRAM) or a static memory (SRAM).

[0065] The data may be located in storage system 112 as shown, or in memory system 104. Processor 106 generally manipulates the data in integrated circuit memories 116, 120 and then copies such data to medium 118 after processing is complete. Various mechanisms for managing data movement between medium 118 and integrated circuit memory devices 116, 120 are known and the invention is not limited thereto. The invention is not limited to any particular memory system 116 or storage system 112.

[0066] Although computer system 104 is shown by way of example as one type of computer system on which various aspects of the invention may be implemented, it should be understood that aspects of the invention are not limited to being implemented on a computer system such as that shown in Figure 8. Various aspects of the invention may be practiced on one or more computers having different architectures or components than those shown in Figure 8.

[0067] The computer system 104 may be a general-purpose computer system programmable using a high-level computer programming language. The computer system 104 may also be implemented using specially programmed dedicated hardware. In the computer system 104, the processor 106 is typically a commercially available processor, such as a Pentium, Core, Core Vpro, Xeon or Itanium class processor available from Intel Corporation. Many other processors are available. Such a processor typically runs an operating system, which may be, for example, an operating system provided by Microsoft Corporation or Apple Corporation, including versions for mobile devices as well as PCs, iOS, Android OS operating systems, or UNIX available from a variety of sources. Many other operating systems may be used.

[0068] Various embodiments of the invention may be programmed using an object-oriented programming language such as SmallTalk, Python, Java, C++, Ada, or C# (C-Sharp). Other object-oriented programming languages ​​may be used. Alternatively, functional, scripting, and / or logic programming languages ​​may be used. Various aspects of the invention may be implemented in a non-programmed environment (e.g., documents created in HTML, XML, or other formats that render aspects of a Graphical User Interface (GUI) or perform other functions when displayed in a browser program window). Various aspects of the invention may be implemented using various Internet technologies such as, for example, Common Gateway Interface (CGI) scripts, PHP Hypertext Preprocessor (PHP), Active Server Pages (ASP), Hypertext Markup Language (HTML), Extensible Markup Language (XML), Java, JavaScript, and open source libraries for extending Javascript, Asynchronous JavaScript and XML (AJAX), Flash, and other programming methods. Additionally, various aspects of the invention may be implemented in a cloud-based computing platform such as the EC2 platform available from Amazon.com (Seattle, Washington), among others. Various aspects of the present invention may be implemented as programmed or non-programmed elements, or any combination thereof.

[0069] A particular example of a vision or imaging system as described above includes a camera (e.g., input device 108) having an image sensor configured to provide digital images and / or digital video to a computer system (e.g., computer system 104) that operates a delivery system (e.g., delivery system 40) as described in this disclosure. One example of an image sensor is a complementary metal oxide semiconductor (CMOS). The image sensor generates digital images or digital video frames that include image features such as the fiducials described above. Images generated by the sensor are processed (e.g., by controller 18 or processor 106) to perform functions of the delivery system, including calibrating the camera and determining the camera-to-needle offset distance of the delivery unit (e.g., output device 110).

[0070] To operate a feeding system as described in this disclosure, the processor 106 executes one or more software programs stored in the memory 116 and / or storage device 112. As an example, a control loop may be provided to control and operate the feeding mechanism, motors, and other devices electronically connected to the computer system 104. Such a control loop may be implemented by the processor 106 executing stored software to receive input data, such as images generated by the vision system and / or the status of the feeding unit, process the input data to determine an action, such as moving the feeding unit to a particular location on the substrate, and at a later point in time obtain new input data, then process the new data to determine a new location to move the feeding head to.

[0071] The stored software may also receive information and / or provide that information to a display unit (e.g., display unit 28) of the dispensing system. The display unit displays a GUI that the user interacts with to receive user input to change or select operations to be performed on the dispensing system. In some examples, the display unit 28 is a touch screen. In other examples, the user interacts with the GUI via a keyboard and mouse. The display unit in some examples provides status indications to the user as the dispensing operation progresses. For example, a vision system may track the progress of the dispensing unit as material is dispensed onto the substrate and provide an indication of that progress on the display unit. In other examples, for example, a certain point in the dispensing progress may be reached where user input is required, after which the GUI prompts the user for confirmation to continue with the subsequent motor and dispensing operation.

[0072] It should be understood that the software functions described above are merely examples, and that the computer system 104 may be configured to control various additional aspects of the delivery system described in this disclosure.

[0073] In some embodiments, the controller can be configured to use machine learning techniques to develop algorithms that dispense materials around the same package and / or the same electronic board. As known in the art, machine learning techniques are directed to techniques of data analysis that automate the building of analytical models. Machine learning techniques are a subset of artificial intelligence that are based on the idea that systems can learn from data, identify patterns, and make decisions with no or minimal human intervention.

[0074] calibration In some embodiments, a table with multiple orientations, for example up to 20 or more, can be provided. Each position is definable almost infinitely within the range of the encoder resolution, for example up to 1111 counts per degree. Each orientation can be specified to include a predefined camera-to-needle calibration, with each calibration including operator-set variables, for example tilt, rotation, and feed height, as they define where the dispensed material will land on the electronics board at a given orientation. These orientations can be obtained from the program and used to dispense to a given location based on the vision data and z-axis sensing data. Multiple orientations can be used throughout the program to achieve the desired results.

[0075] Each orientation has its own camera-to-needle calibration, but it is not necessary to actually feed at each orientation to determine these calibrations: once a smaller number of orientations have been calibrated by feeding and visually located, other orientations can be interpolated to complete the calibration.

[0076] For example, an orientation with the same tilt and feed height requires only two or three rotational positions to interpolate all other rotational positions with the same tilt and feed height.

[0077] In one embodiment, the controller is further configured to calibrate a feed position of a nozzle of the feed unit relative to the vision system by feeding onto an electronic board provided on the support. The controller may include or otherwise communicate with a database having a vision system to nozzle orientation table. In particular, the controller may be configured to calibrate the nozzle orientation based in part on an interpolation of known positions and orientations.

[0078] As used in this disclosure, "sufficiently suitable for simultaneous delivery" means that two or more substrates or patterns are located in known positions, as determined by the controller after inspecting data associated with one or more images acquired by a vision system or camera, such known positions are within a predetermined tolerance, and none of the other acquired data indicates a reason not to deliver to one or more of the substrates or patterns.

[0079] As used in this disclosure, "captured data" refers to data generated within the delivery system, such as visual data, or data transferred from an external source based on prior processing.

[0080] Having thus described several aspects of at least one embodiment of the present disclosure, it is to be understood that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawings are by way of example only.

Claims

1. A supply system for supplying a viscous material onto an electronic substrate, comprising: a frame; a support coupled to the frame and configured to receive and support the electronic substrate during a supply operation; a supply unit configured to supply a viscous material including a solder paste, the supply unit having a nozzle; a gantry assembly coupled to the frame, the gantry assembly including a gantry configured to support the supply unit and move the supply unit in an x-axis direction, a y-axis direction, and a z-axis direction, and an inclination and rotation sub-assembly configured to incline and rotate the supply unit; a controller configured to control the supply unit and the gantry assembly to perform a supply operation of supplying the viscous material onto the electronic substrate, the controller being configured to simultaneously adjust movements of the gantry assembly and the inclination and rotation sub-assembly in the x-axis direction, the y-axis direction, and the z-axis direction while supplying the material along a three-dimensional path to position and direct the nozzle of the supply unit at a predetermined distance and orientation from the electronic substrate; wherein the predetermined distance is at most 5.0 mm; the controller is further configured to move the nozzle of the supply unit at a constant speed relative to components mounted on the electronic substrate, and the controller is configured to move the nozzle so as to achieve a constant speed of 1000 mm / second; the controller is further configured to supply the material from the nozzle of the supply unit at a flow rate configured to deposit a desired amount or density of the material onto the electronic substrate, and the controller is configured to supply the material from the nozzle so as to achieve a flow rate of 2000 mg / second. The supply system.

2. A method of supplying a viscous material onto an electronic substrate using the supply system according to claim 1, the method comprising: delivering an electronic substrate to a supply position within the supply system; capturing at least one image of the electronic substrate; analyzing the at least one image of the electronic substrate to determine the position of the electronic substrate; Performing a supply operation by moving, tilting, and rotating the supply unit, wherein the supply unit is coupled to the gantry configured to support the supply unit and move the supply unit in the x-axis direction, y-axis direction, and z-axis direction, and a tilt-rotation sub-assembly configured to tilt and rotate the supply unit, and performing the supply operation; including; Performing the supply operation includes simultaneously adjusting the movements of the gantry assembly and the tilt-rotation sub-assembly while supplying material along a three-dimensional path to position and direct the nozzle of the supply unit at the predetermined distance and orientation from the electronic substrate; Method.

Images