Ultrasonic welding system, method of use, and related workpiece including welded conductive pins

Abstract

[Solution] An ultrasonic welding system is provided, the ultrasonic welding system including a support structure for supporting a workpiece, a welding head assembly including an ultrasonic transducer carrying a sonotrode, and a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode.

Description

[Technical Field]

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 034,345, filed June 3, 2020, the contents of which are incorporated herein by reference.

[0002] The present invention relates to ultrasonic welding, and more particularly to improved systems and methods for performing ultrasonic welding operations, including conductive pin welding. [Background technology]

[0003] Ultrasonic energy is widely used to form interconnections between two or more materials. For example, wire bonding machines (e.g., ball bonding machines, wedge bonding machines, ribbon bonding machines, etc.) are used to bond wires or ribbons to bonding locations. However, wire bonding utilizes relatively low levels of energy (e.g., cohesive force, ultrasonic energy, etc.). An exemplary wire bonding machine is sold by Click & Soffer Industries, Inc. of Fort Washington, Pennsylvania.

[0004] Some applications involve joining materials other than wire. Welding has been considered for such applications. Ultrasonic welding is also a widely used technique. Ultrasonic welding can use an ultrasonic transducer (e.g., carrying a sonotrode) that converts electrical energy into mechanical motion / scrub (e.g., linear motion / scrub, torsional motion / scrub, etc.). However, existing ultrasonic welding technologies and equipment are limited in providing solutions that can meet market demands in terms of cost, operational efficiency, flexibility, portability, and related factors.

[0005] WO 2018 / 187364 (entitled "Ultrasonic Welding System and Method of Use Thereof"), assigned to Click & Soffer Industries, Inc., relates to improvements in ultrasonic welding technology and is incorporated by reference in its entirety.

[0006] Nevertheless, improvements are needed with respect to ultrasonic welding applications, including ultrasonic pin welding (such pins are typically soldered and / or press-fit into power modules). Therefore, it is desirable to improve ultrasonic welding techniques, including ultrasonic pin welding. The prior art documents relevant to the invention of this application are as follows (including documents cited in the international phase after the international filing date and documents cited when the invention entered the national phase in other countries). (Prior art document) (Patent document) (Patent Document 1) U.S. Patent Application Publication No. 2020 / 0164460 (Patent Document 2) U.S. Patent No. 4,529,115 (Patent Document 3) U.S. Patent Application Publication No. 2012 / 0097339 (Patent Document 4) U.S. Patent Application Publication No. 2017 / 0057155 (Patent Document 5) Korean Patent Publication No. 10-2015-0087232 Summary of the Invention [Means for solving the problem]

[0007] According to another exemplary embodiment of the present invention, an ultrasonic welding system is provided, the ultrasonic welding system including a support structure for supporting a workpiece, a welding head assembly including an ultrasonic transducer carrying a sonotrode, and a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode.

[0008] In accordance with yet another exemplary embodiment of the present invention, there is provided a method of operating an ultrasonic welding system, the method including: (a) supporting a workpiece on a support structure of the ultrasonic welding system; and (b) welding a conductive pin from a conductive pin supply of the ultrasonic welding system to the workpiece using a sonotrode of a weld head assembly of the ultrasonic welding system, the conductive pin supply including a plurality of the conductive pins.

[0009] According to yet another exemplary embodiment of the present invention, there is provided a workpiece including a substrate and a conductive pin ultrasonically welded to the substrate. [Brief explanation of the drawings]

[0010] The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. According to common practice, the various elements of the drawings are not drawn to scale. Rather, the dimensions of the various elements have been arbitrarily expanded or reduced for clarity. The drawings include the following figures: [Figure 1] FIG. 1 is a side block diagram of an ultrasonic welding system in an exemplary embodiment of the present invention. [Figure 2A] FIG. 2A is a side block diagram of another ultrasonic welding system in accordance with another exemplary embodiment of the present invention. [Figure 2B] FIG. 2B is a perspective view of a tip portion of a sonotrode of the ultrasonic welding system of FIG. 2B. [Figure 2C] FIG. 2C is a side view of a conductive pin from the conductive pin supply of the ultrasonic welding system of FIG. 2B. [Figure 3A] FIG. 3A is a side block diagram of yet another ultrasonic welding system in accordance with yet another exemplary embodiment of the present invention. [Figure 3B] 3B-3C are side block diagrams illustrating the drawing of conductive pins from a conductive pin supply using the ultrasonic welding system of FIG. 3A. [Figure 3C]3B-3C are side block diagrams illustrating the drawing of conductive pins from a conductive pin supply using the ultrasonic welding system of FIG. 3A. [Figure 3D] FIG. 3D is a side view of a conductive pin from the conductive pin supply of the ultrasonic welding system of FIG. 3A. [Figure 4] FIG. 4 is a side block diagram of yet another ultrasonic welding system in accordance with yet another exemplary embodiment of the present invention. [Figure 5] FIG. 5 is a side block diagram of yet another ultrasonic welding system in accordance with yet another exemplary embodiment of the present invention. [Figure 6A] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6B] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6C] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6D] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6E] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6F] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 6G] 6A-6G are various views of the conductive pin and sonotrode in various exemplary embodiments of the present invention, illustrating alignment with the keying feature. [Figure 7] FIG. 7 is a side block diagram of an ultrasonic welding system in an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1 illustrates an ultrasonic welding system 100. The ultrasonic welding system 100 includes an input workpiece supply 102 that provides workpieces 102a1, the input workpiece supply 102 being configured to transport multiple workpieces 102a1 (e.g., the workpiece supply 102 may be a transport device such as a magazine handler that transports multiple workpieces 102a1, or may be another supply structure suitable for a particular application of workpieces). Exemplary workpieces 102a1 transported by the input workpiece supply 102 include power modules, power module components, lead frames, battery modules, etc. The workpieces 102a1 are transported from the input workpiece supply 102 to a material processing system 104 (by any desired transport assembly that may be included in the material processing system 104, such as a gripper assembly). The material handling system 104 moves the workpiece 102a1 from the input workpiece supply 102 to the support structure 106 (e.g., using a conveyor assembly, using a gripper assembly, etc.). The support structure 106 supports the workpiece (referred to as a clamped workpiece 102a2 when clamped to the support structure 106 using the workpiece clamp 108 shown in FIG. 5) during the welding operation. After the welding operation (described below with respect to the weld head assembly 112), the currently welded workpiece 102a3 is moved (e.g., using a conveyor assembly, using a gripper assembly) from the portion of the material handling system 104 downstream from the support structure 106 to the output workpiece source 110. Output workpiece supply 110 is configured to receive welded workpieces 102a3 after processing by welding head assembly 112 (in this case, welding head assembly 112 includes ultrasonic transducer 112b carrying sonotrode 202). Output workpiece supply 110 may be a transport device such as a magazine handler that transports multiple welded workpieces 102a3, or may be other supply structure suitable for the workpieces in a particular application.

[0012] The ultrasonic welding system 100 includes a welding head assembly 112. The welding head assembly includes an ultrasonic transducer 112b carrying a sonotrode 202 and is movable along multiple substantially horizontal axes. In the example shown in FIG. 1, the welding head assembly 112 is configured to move along the x-axis and the y-axis of the ultrasonic welding system 100. In the example shown in FIG. 1, the welding head assembly 112 is also configured to move along the z-axis of the ultrasonic welding system 100 and about the theta-axis (Θ-axis) of the ultrasonic welding system 100. Not all of these axes of motion may be required for every application. The axes of motion of the welding head assembly 112 can be used to move the sonotrode 202 to the appropriate welding position relative to the clamped workpiece 102a2. A camera 114 is also provided for imaging operations related to alignment between the sonotrode 202 and the workpiece 102a2 being held, alignment of components of the workpiece 102a2 being held itself, optical inspection of the weld after the welding operation, etc. (In this case, the camera may optionally be carried by the welding head assembly 112 or by other parts of the ultrasonic welding system 100).

[0013] Ultrasonic welding system 100 (or other systems within the scope of the present invention) can be used to weld various types of workpieces. Exemplary workpieces include power modules, lead frames, and battery modules.

[0014] In accordance with the present invention, various types of ultrasonic motion can be imparted to a conductor (e.g., a conductive pin, a signal connector, a conductive terminal, a power terminal, etc.) For example, the sonotrode may be configured to weld the conductor to a workpiece using at least one of a linear ultrasonic motion and a torsional ultrasonic motion.

[0015] Some of these workpieces are configured to receive conductive pins. As used herein, the term "conductive pin" refers to a conductive structure intended to be welded to a workpiece. The conductive pin has a free end (after being welded to the workpiece), and the body of the conductive pin may extend substantially perpendicularly from the "welded" end to the free end. The cross section of the conductive pin may be circular, square, rectangular, or have any desired cross section. The term conductive pin should also be understood to include a conductive receptacle or sleeve (e.g., tubular in shape), where the conductive receptacle / sleeve is ultrasonically welded to the workpiece and is configured to receive another conductive element. According to some exemplary embodiments of the present invention, the ultrasonic welding system 100 includes a conductive pin supply 200 configured to provide a plurality of conductive pins for welding with a sonotrode 202. Exemplary configurations of the conductive pin supply include a grid array (containing columns and rows of conductive pins, oriented for easy removal), a bowl feeder, a hopper, a spool, etc. Alternative configurations are contemplated. The conductive pin supply 200 may be configured to operate with a buffer system so that pins are fed through a staging area and ready to be removed for welding.

[0016] Ultrasonic welding system 100, including conductive pin supply 200 and sonotrode 202, can take a variety of forms. More specifically, different configurations of conductive pin supply 200, different configurations of sonotrode 202, etc. are contemplated. Figures 2A-2C illustrate an exemplary ultrasonic welding system 100a including an exemplary configuration of a conductive pin supply (referred to herein as conductive pin supply 200a and including conductive pins 200a1) and an exemplary configuration of a sonotrode (referred to herein as sonotrode 202a, defining reduced pressure channel 202a1 and coupled to reduced pressure source 204 via piping 204a). 3A-3C illustrate an exemplary ultrasonic welding system 100b including another exemplary configuration of a conductive pin supply (referred to herein as conductive pin supply 200b, including conductive pins 200b1) and an exemplary configuration of a sonotrode (referred to herein as sonotrode 202b, adapted to move with gripper actuator 206 and gripper arm 206a). FIG. 4 illustrates yet another exemplary ultrasonic welding system 100c that is substantially similar to ultrasonic welding system 100b (of FIGS. 3A-3C), except that ultrasonic welding system 100c includes gripper actuator 208, first gripper arm 208a, and second gripper arm 208b. Except as described herein, each of ultrasonic welding systems 100a, 100b, and 100c is substantially similar to ultrasonic welding system 100 described above.

[0017] 2A-2C, sonotrode 202a is configured to withdraw conductive pins 200a1 from conductive pin supply 200a, and weld head assembly 112 is configured to convey (through its various axes of motion) withdrawn conductive pins 200a1 toward and ultrasonically weld conductive pins 200a1 to clamped workpiece 102a2. Sonotrode 202a defines a reduced pressure channel 202a1 connected to reduced pressure source 204 via piping 204a for withdrawing conductive pins 200a1 from conductive pin supply 200a.

[0018] Referring specifically to FIG. 2B, the tip portion 202a3 of the sonotrode 202 is shown. The vacuum channel 202a1 is defined by the sonotrode 202a. The working surface 202a2 of the sonotrode 202a is configured to contact the weld portion of the conductive pin and press it against the workpiece for ultrasonic welding (see, for example, the weld portion of the conductive pin shown in FIG. 2C). Also shown is the vacuum hole 202a4 of the sonotrode 202a (configured to engage with the tubing 204a as shown in FIG. 2A). FIG. 2C is a side view of the conductive pin 200a1 (e.g., a round conductive pin) including a body portion 200a1a, a weld portion 200a1b, and a free end 200a1c. After being welded to the workpiece via the weld portion 200a1b, the body portion 200a1a can extend substantially vertically from the weld portion 200a1b to the free end 200a1c. The free end 200a1c (or other portion of the welded conductive pin 200a1) is available for electrical connection as needed for the given workpiece.

[0019] 3A-3C, the weld head assembly 112 includes a gripper mechanism configured to pull conductive pins 200b1 from a conductive pin supply 200b. In FIG. 3A, the gripper mechanism includes a gripper actuator 206 and a movable arm 206a. Actuation of the gripper actuator 206 moves the movable arm 206a between (i) an open position in which the movable arm 206a engages the conductive pins 200b1, as shown in FIG. 3B, and (ii) a closed position in which the movable arm 206a holds the conductive pins 200b1 in a position of movement toward the clamped workpiece 102a2, as shown in FIG. 3C. As shown in FIG. 3B, the movable arm 206a aligns the conductive pins 200b1 with the sonotrode 202b in the closed position and holds the conductive pins 200b1 in position relative to the sonotrode 202b. The welding head assembly 112 is configured to convey the extracted conductive pin 200b1 toward the workpiece and ultrasonically weld the conductive pin 200b1 to the clamped workpiece 102a2.

[0020] 4, the weld head assembly 112 includes another gripper mechanism configured to retrieve conductive pin 200b1 from conductive pin supply 200b. In FIG. 4, the gripper mechanism includes a gripper actuator 208, a movable arm 208a, and a fixed arm 208b. Actuation of gripper actuator 208 causes movable arm 208a to move between (i) an open position in which it engages conductive pin 200b1 and (ii) a closed position in which it holds conductive pin 200b1 in position for movement toward the gripped workpiece 102a2. As shown in FIG. 4, movable arm 208a moves to lock conductive pin 200b1 relative to fixed arm 208b in the closed position, thereby aligning conductive pin 200b1 with sonotrode 202b. The welding head assembly 112 is configured to convey the extracted conductive pin 200b1 toward the held workpiece 102a2 and ultrasonically weld the conductive pin 200b1 to the held workpiece 102a2.

[0021] Referring specifically to conductive pin 200b1 shown in Figures 3A-3C and 4 and detailed in Figure 3D, conductive pin 200b1 has a different configuration compared to conductive pin 200a1 in Figures 2A-2C. Conductive pin 200b1 includes body portion 200b1a, weld portion 200b1b, and free end 200b1c. After being welded to a workpiece via weld portion 200b1b, body portion 200b1a may extend substantially perpendicularly from weld portion 200b1b to free end 200b1c. Free end 200b1c (or other portion of welded conductive pin 200b1) is available for electrical connection as needed for the given workpiece.

[0022] It should be understood that aspects of the present invention relate specifically, but are not limited to, ultrasonic welding systems for welding conductive pins to workpieces. For example, according to some exemplary embodiments of the present invention, a sonotrode is configured to weld a conductive pin to a workpiece and also weld another conductor (e.g., a conductive terminal such as a power terminal) to the workpiece. The sonotrode may weld both the conductive pin and the other conductor, such as a power terminal, using a single working area (e.g., working surface 202a2 shown in FIG. 2B ). However, in other embodiments of the present invention, the sonotrode includes a first area configured to contact the conductive pin for welding to the workpiece and a second area configured to contact the power terminal for welding to the workpiece.

[0023] In another exemplary embodiment of the present invention, an ultrasonic welding system includes a second welding head assembly having a second ultrasonic transducer carrying a second sonotrode, the second welding head assembly being configured to weld a power terminal to a workpiece. Referring specifically to FIG. 5 , an ultrasonic welding system 500 is shown. The ultrasonic welding system 500 includes a first ultrasonic welding subsystem 502 (which may be substantially similar to the ultrasonic welding system 100 shown in FIG. 1 of WO 2018 / 187364 and may be similar to the welding systems disclosed herein except that the first ultrasonic welding subsystem 502 includes a sonotrode 112a and does not include a conductive pin supply) and a second ultrasonic welding subsystem 504. The second ultrasonic welding subsystem 504 may be, for example, the ultrasonic welding system 100 shown in FIG. 1 , the ultrasonic welding system 100a shown in FIG. 2A , the ultrasonic welding system 100b shown in FIG. 3A , the ultrasonic welding system 100c shown in FIG. 4 , etc. First ultrasonic welding subsystem 502 is configured to weld a conductor (e.g., a larger power conductor such as power terminal 506), and second ultrasonic welding subsystem 504 is configured to weld a conductive pin as described herein. Figure 5 shows an example of an output workpiece 102a3' of ultrasonic welding system 500. Output workpiece 102a3' includes a substrate (not labeled), conductive terminal 506 that is ultrasonically welded to the substrate, and conductive pin 200a1 that is ultrasonically welded to the substrate. For example, workpiece 102a3' may be a power semiconductor module, in which case conductive terminal 506 is a power terminal of the power semiconductor module, and conductive pin 200a1 is a signal connection of the power semiconductor module.

[0024] Although FIG. 5 illustrates conductive pin supply 200a including conductive pin 200a1 (i.e., similar to the configuration of FIG. 2A), the inventive features of ultrasonic welding system 500 (including ultrasonic welding system 504) can be applied to any type of conductive pin within the scope of the present invention (e.g., conductive pin 200b1 shown in FIG. 3A), including corresponding modifications to the weld head assembly.

[0025] According to some exemplary embodiments of the present invention, during a welding operation, exemplary technical specifications include: (i) the sonotrode is configured to operate at a coupling force of 5 to 500 kg, or the sonotrode is configured to operate at a coupling force of 5 to 300 kg, or the sonotrode is configured to operate at a coupling force of 5 to 100 kg; (ii) the sonotrode tip has a motion amplitude of 5 to 150 microns, or the sonotrode tip has a motion amplitude of 5 to 120 microns, or the sonotrode tip has a motion amplitude of 5 to 100 microns; and (iii) the sonotrode is configured to provide a distance of 1.5 to 30 mm between a first portion of a workpiece and a second portion of a workpiece. 2 or between a first portion of the workpiece and a second portion of the workpiece, the first portion of the workpiece having an area in the range of 1.5 to 20 mm. 2 or between a first portion of the workpiece and a second portion of the workpiece, the first portion of the workpiece having an area in the range of 1.5 to 16 mm. 2 and (iv) the sonotrode is configured to operate at a frequency in the range of 15-40 kHz, or the sonotrode is configured to operate at a frequency in the range of 20-35 kHz, or the sonotrode is configured to operate at a frequency in the range of 20-30 kHz. Exemplary thicknesses of the conductive contact of the contact element (the portion of the workpiece that the sonotrode contacts) include 0.2-3 mm, 0.2-1.5 mm, and 0.2-1.2 mm.

[0026] Although not specifically shown, variations are contemplated within the scope of the present invention. For example, according to some exemplary embodiments of the present invention, the weld head assembly may define a keying feature configured to align with a corresponding keying feature on the conductive pin, such that the conductive pin held by the weld head assembly is properly aligned with the sonotrode. Figures 6A-6D and 6E-6G show examples of such embodiments of the present invention. The conductive pins and sonotrodes of Figures 6A-6D and 6E-6G may be implemented in connection with any of the ultrasonic welding systems disclosed herein (e.g., ultrasonic welding systems 100, 100a, 100b, 100c, 504, and 700) or any other ultrasonic welding system within the scope of the present invention.

[0027] 6A and 6B are side and top views, respectively, of a conductive pin 600a1 (e.g., a round conductive pin) including a body portion 600a1a, a weld portion 600a1b, a free end 600a1c, and a key feature 600a1d. The key feature 600a1d of the conductive pin 600a1 is used to align with a corresponding key feature of a weld head assembly (e.g., a keyway), thereby ensuring that the conductive pin 600a1 held by the weld head assembly is properly aligned with the sonotrode 602a. After being welded to a workpiece via the weld portion 600a1b, the body portion 600a1a can extend substantially vertically from the weld portion 600a1b to the free end 600a1c. The free end 600a1c (or other portion of the welded conductive pin 600a1) is available for electrical connection as needed for the given workpiece. FIG. 6C is an end view of sonotrode 602a, showing that it includes a vacuum channel 602a1 defined by sonotrode 602a. In vacuum channel 602a1, sonotrode 602a defines a key feature 602a1d (e.g., a recess). When conductive pin 600a1 engages sonotrode 602a, key feature 600a1d engages key feature 602a1d. FIG. 6D shows conductive pin 600a1 aligned with sonotrode 602a of a welding head assembly (not shown, see welding head assembly 112 in the various figures).

[0028] 6E and 6F are side and top views, respectively, of conductive pin 600b1 (e.g., a conductive pin having an "L" shape), shown to include body portion 600b1a, weld portion 600b1b, free end 600b1c, and key feature 600b1d (e.g., a protrusion). Key feature 600b1d of conductive pin 600b1 may be used to align with a corresponding key feature (e.g., a keyway) on gripper arm 206a' (similar to gripper arm 206a in FIGS. 3A-3C) so that conductive pin 600b1 is held in place by gripper arm 206a' of a welding head assembly, thereby aligning conductive pin 600b1 with sonotrode 602a. After being welded to the workpiece via weld portion 600b1b, body portion 600b1a may extend substantially vertically from weld portion 600b1b to free end 600b1c. Free end 600b1c (or other portion of welded conductive pin 600b1) is available for electrical connection as needed for the given workpiece. Figure 6G is a top view of gripper arm 206a' engaged with conductive pin 600b1. Gripper arm 206a' defines key feature 206a'1 (i.e., recess). When conductive pin 600b2 engages gripper arm 206a', key feature 206a'1 engages key feature 602b1d.

[0029] 6A-6G are exemplary in nature, and alternative keying or alignment features are contemplated within the scope of the present invention. For example, although keying feature 600a1d protrudes from body portion 600a1a of conductive pin 600a1, a recessed keying feature may be used with such conductive pin if the mating keying feature on the sonotrode (or other part of the bond head assembly) is a protruding feature.

[0030] Furthermore, according to some exemplary embodiments of the present invention, the sonotrode (or other aspects of the weld head assembly, such as the gripper mechanism) may not function as a pick tool. Rather, the ultrasonic welding system may further include a pick tool configured to withdraw conductive pins from a conductive pin supply, where the withdrawn conductive pins are transferred to the weld head assembly for welding to the workpiece.

[0031] 7, an ultrasonic welding system 700 is shown. The ultrasonic welding system 700 (which is similar to the ultrasonic welding systems herein described in detail above) includes a pick tool 702. The pick tool 702 includes a contact portion 702a. According to some exemplary embodiments of the present invention, the pick tool 702 withdraws (or receives) a conductive pin 200a1 from a conductive pin supply 200a. The conductive pin 200a1 is transferred to the welding head assembly 112 for welding to the workpiece 102a2. The contact portion 702a may have a number of different alternative configurations that engage when retrieving the conductive pin 200a1 from the conductive pin supply 200a and transferring the conductive pin 200a1 to the sonotrode 202a of the welding head assembly 112. Exemplary configurations of the contact portion 702a include a magnetic holding mechanism, a mechanical gripper mechanism, and a vacuum-based holding mechanism, among others.

[0032] Referring again to FIG. 7 , once the pick tool 702 holds the conductive pin 200a1, it can be moved toward the sonotrode 202a for transfer of the conductive pin 200a1 (see the dotted line of the conductive pin 200a1 engaged with the sonotrode 202a). Alternatively, the sonotrode 202a (carried by the welding head assembly 112) may be moved toward the pick tool 702 for transfer of the conductive pin 200a1. In yet another alternative, both the pick tool 702 and the sonotrode 202a may be moved toward each other for transfer of the conductive pin 200a1. While FIG. 7 shows the conductive pin supply 200a including the conductive pin 200a1 (i.e., similar to the configuration of FIG. 2A ), the inventive features of the ultrasonic welding system 700 may be applied to any type of conductive pin (e.g., the conductive pin 200b1 shown in FIG. 3A ) within the scope of the present invention, with corresponding modifications to the welding head assembly.

[0033] Although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications can be made in the details within the scope of the claims and their equivalents without departing from the invention.

Claims

1. 1. An ultrasonic welding system comprising: a support structure configured to support a workpiece; a welding head assembly including an ultrasonic transducer carrying a sonotrode; a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode; and the sonotrode of the welding head assembly is configured to draw conductive pins from the conductive pin supply, and the welding head assembly is configured to convey the drawn conductive pins toward the workpiece and ultrasonically weld the conductive pins to the workpiece. Ultrasonic welding system.

2. 10. The ultrasonic welding system of claim 1, wherein the sonotrode defines a vacuum channel for drawing the conductive pins from the conductive pin supply.

3. An ultrasonic welding system, comprising: a support structure configured to support a workpiece; a welding head assembly including an ultrasonic transducer carrying a sonotrode; a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode; and the welding head assembly including a gripper mechanism configured to extract conductive pins from the conductive pin supply, the welding head assembly configured to convey the extracted conductive pins toward the workpiece and ultrasonically weld the conductive pins to the workpiece. Ultrasonic welding system.

4. 4. The ultrasonic welding system of claim 3, wherein the gripper mechanism includes a movable arm configured to move between (i) an open position in which the gripper mechanism engages the conductive pin and (ii) a closed position in which the gripper mechanism holds the conductive pin in a position for movement toward the workpiece.

5. 5. The ultrasonic welding system of claim 4, wherein the movable arm aligns the conductive pin with the sonotrode in the closed position.

6. 4. The ultrasonic welding system of claim 3, wherein the gripper mechanism includes a movable arm and a fixed arm, the movable arm configured to move between (i) an open position in which it engages the conductive pin and (ii) a closed position in which it holds the conductive pin in a position of movement toward the workpiece, and the movable arm aligns the conductive pin with the sonotrode in the closed position.

7. An ultrasonic welding system, comprising: a support structure configured to support a workpiece; a welding head assembly including an ultrasonic transducer carrying a sonotrode; a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode; and the weld head assembly defining key features configured to align with corresponding features on the conductive pin, such that the conductive pin held by the weld head assembly is properly aligned with the sonotrode; Ultrasonic welding system.

8. An ultrasonic welding system, comprising: a support structure configured to support a workpiece; a welding head assembly including an ultrasonic transducer carrying a sonotrode; a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode; a pick tool configured to extract conductive pins from the conductive pin supply, the extracted conductive pins being transferred to the weld head assembly for welding to the workpiece; and An ultrasonic welding system having:

9. An ultrasonic welding system, comprising: a support structure configured to support a workpiece; a welding head assembly including an ultrasonic transducer carrying a sonotrode; a conductive pin supply configured to provide a plurality of conductive pins for welding with the sonotrode; and the sonotrode including a first region configured to contact the conductive pin for welding to the workpiece and a second region configured to contact a power terminal for welding to the workpiece. Ultrasonic welding system.

10. 10. The ultrasonic welding system of claim 1, 3, 7, 8, or 9, wherein the welding head assembly is configured to move along multiple separate axes of motion.

11. 11. The ultrasonic welding system of claim 10, wherein the plurality of separate axes of motion include an x-axis, a y-axis, and a z-axis.

12. 11. The ultrasonic welding system of claim 10, wherein the welding head assembly is configured to move about a theta axis.

13. 10. The ultrasonic welding system of claim 1, 3, 7, 8, or 9, wherein the sonotrode is configured to weld the conductive pin to the workpiece and to weld a power terminal to the workpiece.

14. 10. The ultrasonic welding system of claim 1, further comprising a second welding head assembly including a second ultrasonic transducer carrying a second sonotrode, the second welding head assembly configured to weld a power terminal to the workpiece.

15. 1. A method of operating an ultrasonic welding system, comprising: supporting a workpiece on a support structure of the ultrasonic welding system; welding a conductive pin from a conductive pin supply unit of the ultrasonic welding system to the workpiece using a sonotrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply unit including a plurality of the conductive pins; and Prior to the welding step, the method further includes (i) withdrawing the conductive pin from the conductive pin supply using the sonotrode of the welding head assembly; and (ii) conveying the withdrawn conductive pin toward the workpiece using the welding head assembly. method.

16. 16. The method of claim 15, wherein the sonotrode defines a vacuum channel for drawing the conductive pins from the conductive pin supply.

17. A method of operating an ultrasonic welding system, comprising: supporting a workpiece on a support structure of the ultrasonic welding system; welding a conductive pin from a conductive pin supply unit of the ultrasonic welding system to the workpiece using a sonotrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply unit including a plurality of the conductive pins; and the welding head assembly includes a gripper mechanism, the method further comprising: (i) withdrawing the conductive pin from the conductive pin supply using the gripper mechanism; and (ii) conveying the withdrawn conductive pin toward the workpiece using the welding head assembly. method.

18. 20. The method of claim 17, wherein the gripper mechanism includes a movable arm configured to move between (i) an open position in which it engages the conductive pin, and (ii) a closed position in which it holds the conductive pin in a position of movement toward the workpiece.

19. 20. The method of claim 18, wherein the movable arm aligns the conductive pin with the sonotrode in the closed position.

20. 18. The method of claim 17, wherein the gripper mechanism includes a movable arm and a fixed arm, the movable arm configured to move between (i) an open position in which it engages the conductive pin and (ii) a closed position in which it holds the conductive pin in a position of movement toward the workpiece, the movable arm aligning the conductive pin with the sonotrode in the closed position.

21. A method of operating an ultrasonic welding system, comprising: supporting a workpiece on a support structure of the ultrasonic welding system; welding a conductive pin from a conductive pin supply unit of the ultrasonic welding system to the workpiece using a sonotrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply unit including a plurality of the conductive pins; and the weld head assembly defining key features configured to align with corresponding features on the conductive pin, such that the conductive pin held by the weld head assembly is properly aligned with the sonotrode; method.

22. A method of operating an ultrasonic welding system, comprising: supporting a workpiece on a support structure of the ultrasonic welding system; welding a conductive pin from a conductive pin supply unit of the ultrasonic welding system to the workpiece using a sonotrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply unit including a plurality of the conductive pins; and the method further comprising the steps of: (i) withdrawing the conductive pin from the conductive pin supply with a pick tool; and (ii) transferring the conductive pin from the pick tool to the weld head assembly for welding to the workpiece. method.

23. A method of operating an ultrasonic welding system, comprising: supporting a workpiece on a support structure of the ultrasonic welding system; welding a conductive pin from a conductive pin supply unit of the ultrasonic welding system to the workpiece using a sonotrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply unit including a plurality of the conductive pins; welding a power terminal to the workpiece using the sonotrode; and the sonotrode including a first region configured to contact the conductive pin for welding to the workpiece and a second region configured to contact a power terminal for welding to the workpiece. method.

24. 24. The method of any one of claims 15, 17, 21, 22, or 23, wherein the welding head assembly is configured to move along multiple separate axes of motion of the ultrasonic welding system.

25. 25. The method of claim 24, wherein the plurality of distinct axes of motion include an x-axis, a y-axis, and a z-axis.

26. 25. The method of claim 24, wherein the weld head assembly is configured to move about a theta axis.

27. 24. The method of any one of claims 15, 17, 21, 22, or 23, wherein the ultrasonic welding system includes a second weld head assembly including a second ultrasonic transducer carrying a second sonotrode, the method further comprising welding a power terminal to the workpiece using the second sonotrode.

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