Multipoint controller for power distribution to multiple probes in an ultrasonic welding system

Abstract

A system for powering a plurality of ultrasonic welding probes from M power sources includes N multipoint units and a base. Each of the N multipoint units includes a housing, a plurality of analog or digital inputs configured to carry distance information related to the probing distances of the plurality of ultrasonic welding probes, a dedicated high-voltage input connector connectable via a high-voltage cable to the dedicated high-voltage output connector of one of the M power sources, and a microcontroller. The microcontroller is configured to direct power from the dedicated high-voltage input connector to corresponding ones of the plurality of ultrasonic welding probes and to sample the distance information of the plurality of ultrasonic welding probes at a rate of at least once per millisecond. The base houses the M power sources, where M and N are integers greater than or equal to 1.

Description

[Technical field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. patent application Ser. No. 16 / 541,954, filed Aug. 15, 2019, and U.S. patent application Ser. No. 16 / 898,030, filed June 10, 2020, each of which is hereby incorporated by reference in its entirety.

[0002] [Technical field] TECHNICAL FIELD This disclosure relates to ultrasonic welding, and more particularly to a system and method for powering multiple ultrasonic welding probes. [Background technology]

[0003] Ultrasonic welding is an efficient means of joining components during manufacturing. It can be used on plastic parts and fabrics during automotive manufacturing, medical manufacturing, etc.

[0004] Ultrasonic manufacturing sometimes requires the use of one or more welding probes. Each welding probe can be customized and controlled for a specific weld for a specific component. The welding probes must have access to an ultrasonic power source, and with a multi-probe controller the power source can be shared among a group of welding probes. Power sharing reduces costs in a manufacturing environment. Manufacturers can save money by acquiring a minimum number of power sources for a group of welding probes. Summary of the Invention [Problem to be solved by the invention]

[0005] While sharing a power source among multiple welding probes in a manufacturing environment can reduce costs, it can increase the complexity of connecting the power source to the welding probes. It can also increase the complexity of the manufacturing process in which the welding probes are required. Therefore, there is a need for an alternative system and method for sharing power among multiple probes. The present disclosure is directed to solving problems related to power distribution to multiple probes and addresses other needs. [Means for solving the problem]

[0006] In one embodiment of the present disclosure, a system is provided for powering a plurality of ultrasonic welding probes from M power sources. The system includes N multipoint units, each of which includes a housing, a plurality of analog inputs configured to carry distance information related to the probing distances of the plurality of ultrasonic welding probes, a dedicated high voltage input connector connectable via a high voltage cable to a dedicated high voltage output connector of one of the M power sources, and a microcontroller. The microcontroller is configured to direct power from the dedicated high voltage input connector to corresponding ones of the plurality of ultrasonic welding probes and sample the distance information of the plurality of ultrasonic welding probes at a rate of at least once per millisecond. The system further includes a base that houses the M power sources; M and N are both integers equal to or greater than 1. As will be appreciated by those skilled in the art, the analog inputs for the distance sensors could also be implemented as digital (or some type of fieldbus) type inputs for the distance sensors with appropriate outputs.

[0007] In one embodiment of the present disclosure, a method is provided for providing power from a first power source of M power sources to a plurality of ultrasonic welding probes coupled to a first multipoint unit of N multiport units, the method comprising: pairing the first multipoint unit with the first power source, where each of the N multipoint units has at least one Ethernet port for connecting the N multiport units to the M power sources in the network; receiving distance information regarding the probe distances of the plurality of ultrasonic welding probes via a plurality of analog inputs of the first multipoint unit; receiving power from the first power source via a dedicated high voltage input connector of the first multipoint unit, where the dedicated high voltage input connector is connectable to a dedicated high voltage output connector of the first power source via a high voltage cable; and directing power from the first power source to corresponding ones of the plurality of ultrasonic welding probes via a microcontroller of the first multipoint unit. The distance information of the corresponding ones of the plurality of ultrasonic welding probes is sampled at a rate of at least once per millisecond by the function of the microcontroller, where M and N are both integers of 1 or more.

[0008] To enable those skilled in the art to discern the above and additional aspects and implementations of the present disclosure, detailed descriptions of various embodiments and / or implementations are provided and are made with reference to the drawings, a brief description of which is provided in the following sections.

[0009] These and other advantages of the present disclosure will become apparent upon reading the following detailed description and upon reference to the drawings. [Brief description of the drawings]

[0010] [Figure 1A] FIG. 1 depicts a base and cassette style machine for ultrasonic welding according to one embodiment of the present disclosure. [Figure 1B] FIG. 1B illustrates a depiction of a cassette of the base and cassette style machine of FIG. 1A. [Diagram 2] FIG. 1 is a schematic diagram of a base and cassette style machine showing component placement for ultrasonic welding in the prior art. [Diagram 3] FIG. 1 illustrates a multipoint controller unit with Ethernet according to an embodiment of the present disclosure. [Figure 4A] FIG. 1 is a perspective view of a multipoint controller unit according to an embodiment of the present disclosure. [Figure 4B] FIG. 4B is another perspective view of the multipoint controller unit of FIG. 4A. [Diagram 5] FIG. 1 is a schematic diagram of a base and cassette style machine having a multi-point controller unit according to one embodiment of the present disclosure. [Figure 6] FIG. 1 is a schematic diagram of a base and cassette style machine having multi-point controller units connected in a daisy chain configuration in accordance with one embodiment of the present disclosure. [Figure 7A] FIG. 1 is a schematic diagram of a base and cassette style machine with two multipoint controller units paired with one power source according to one embodiment of the present disclosure. [Figure 7B] FIG. 1 is a schematic diagram of a base and cassette style machine with two multipoint controller units paired with one power source according to one embodiment of the present disclosure. [Figure 8] FIG. 1 is a flow diagram depicting a welding process using a multi-point controller unit according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Because the present disclosure is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail herein. It should be understood, however, that the present disclosure is not intended to be limited to the specific forms disclosed. Rather, the present disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

[0012] Ultrasonic welding machines can generally be used in the form of a "cassette" style machine, such as the base and cassette style machine 100 shown in FIG. 1A. The base and cassette style machine 100 has a base 106 that straddles a cassette 104. The base 106 has power supplies 102-1, 102-2, 102-3, and 102-4 mounted thereon. FIG. 1B shows the cassette 104 without the base 106. The cassette 104 shown can hold multiple ultrasonic welding probes 110 and several multiple probe controller units 112. The ability to hold multiple cassettes on a single base allows for more cost-effective manufacturing of articles with distinctly different details (e.g., large quantities of plastic parts). This cost-effective manufacturing can be applied to automotive manufacturing, such as the manufacture of automotive door panels, spoilers, instrument panels, etc.

[0013] A cassette style machine (e.g., base and cassette style machine 100) allows for quick change of cassettes (e.g., cassette 104). The cassette style machine base can have 6-12 ultrasonic generators (e.g., power supplies 102) and a corresponding number of multi-probe controller units in the cassette of the cassette style machine. The cassette can have about 80 ultrasonic probes. The ultrasonic probes in the cassettes can have analog distance sensors for welding control. The analog distance sensors are often connected to analog input / output (I / O) cards attached to a programmable logic controller (PLC) in the cassette style machine base.

[0014] The signals generated by these analog distance sensors can be sensitive to electronic noise, and in conventional systems the wires connecting the PLC's analog I / O card to the analog distance sensors must be carefully routed and shielded to protect against that noise.

[0015] The base and cassette style machine 100 has a power supply 102, a multi-probe controller unit 112, and a number of ultrasonic welding probes 110 in separate locations. The multi-probe controller unit 112 and the ultrasonic welding probes 110 are closer to each other than the power supply 102 to the multi-probe controller unit 112. There are quick change connectors on the base and cassette style machine 100 that can be used to connect the power supply 102 to the multi-probe controller unit 112. Signals can be passed between components through these quick change connectors. Examples of signals that can be passed through these connectors include high voltage ultrasonic power signals from each power supply 102, discrete control signals, and analog signals from distance sensors.

[0016] The use of quick change connectors involves customization of the connectors that engage and mate with both the base 106 and the cassette 104. The machine builder is required to fabricate multiple custom cables with wire terminations and shielding appropriate for high electrical noise environments. This customization can add significant manufacturing and troubleshooting costs. Field support and maintenance of these customized cassette style machines can be tedious and expensive.

[0017] To illustrate the differences between embodiments of the present disclosure and the prior art, Figure 2 provides an overview of a base and cassette style machine 200, showing the prior art component layout of an ultrasonic power supply 202, a PLC with analog I / O card 201, and a multi-probe controller unit 212. The PLC with analog I / O card 201 and ultrasonic power supply 202 are located in the base 206, while the multi-probe controller unit 212 and set of probes 210 are located in the cassette 204.

[0018] The PLC with analog I / O card 201 is discretely connected to each of the ultrasonic power supplies 202-1, 202-2, ..., 202-M via corresponding ones of the wires 222-1, 222-2, ..., 222-M. The wires 222-1 to 222-M allow the PLC with analog I / O card 201 to communicate with the ultrasonic power supplies 202-1 to 202-M and vice versa. Each of the ultrasonic power supplies 202 provides power to the probe set 210 via a high voltage ultrasonic cable 214. The ultrasonic power supplies 202 also provide power to the multi-probe controller unit 212 via a customized cable 216. The quick change connector 220 provides an interface between the ultrasonic power supplies 202 and the multi-probe controller unit 212 for powering and communicating with the multi-probe controller unit 212. A quick change connector 218 provides an interface between the ultrasonic power supply 202 and the multi-probe controller unit 212 for supplying ultrasonic signals to the probe set 210. Each probe in each probe set 210-1, 210-2, ... 210-M has an actuator with an analog distance sensor that can send distance information from the analog distance sensor to the PLC with analog I / O card 201 via one or more sensor cables 208 and quick disconnects 219.

[0019] The PLC with analog I / O card 201 communicates with each ultrasonic power source 202-1, 202-2, ... 202-M to perform ultrasonic welding using the distance and / or position of the probe set 210. The PLC with analog I / O card 201 notifies the ultrasonic power sources 202 via wire 222 that a selected probe in the probe set 210 should be activated. The corresponding one of the ultrasonic power sources 202, i.e., the one responsible for the selected probe, updates the signal on the individual customized cable 216 connected to the corresponding multi-probe controller unit 212, so that the selected probe is selected by the logic circuitry in the individual multi-probe controller unit 212.

[0020] Thereafter, the selected probe is positioned within a suitable distance from the part to be welded by monitoring the distance and position using the analog distance sensor of the selected probe. The PLC 201 with analog I / O card monitors the distance based on the distance information captured by the analog distance sensor.

[0021] Then, the PLC with analog I / O card 201 sends a signal to the corresponding one of the ultrasonic power supplies 202 to turn on the ultrasonic output unit that supplies ultrasonic power to the selected probe. The PLC with analog I / O card 201 then monitors the analog distance sensor, and when a suitable reading is reached, sends a signal to the corresponding one of the ultrasonic power supplies 202 to stop the ultrasonic output. Alternatively, a weld by time mode or weld by energy mode that does not require a distance sensor may be used, or the welding may be controlled by the corresponding one of the power supplies 202, and the PLC with analog I / O card 201 may use distance information to determine whether or not a good weld condition has occurred.

[0022] The PLC with Analog I / O Card 201 can then read the welding cycle from the corresponding one of those ultrasonic sources, if available. This process can be repeated with different probe output selections. The drawback of using the PLC with Analog I / O Card 201 is that since the PLC with Analog I / O Card 201 is responsible for multiple systems and not just the welding process, there can be a delay in the distance information monitored by the PLC with Analog I / O Card 201, which can cause processing to be postponed. This delay can be as much as 20 milliseconds, which can result in poor welds on the parts or a very slow welding process.

[0023] Some embodiments of the present disclosure provide a base and cassette style machine with a multipoint controller unit that has an analog input that receives distance information from a distance sensor. Some embodiments of the present disclosure provide Ethernet style communication instead of discrete control signals.

[0024] 3 is a block diagram of a multipoint controller unit 312 according to embodiments of the present disclosure. The multipoint controller unit 312 may incorporate one or more high voltage relays 350 that control the delivery of high voltage ultrasonic signals to ultrasonic probes connected to the multipoint controller unit 312. The multipoint controller unit 312 has an SHV port 352 that interfaces with ultrasonic probes to deliver high voltage ultrasonic signals to the ultrasonic probes. The multipoint controller unit 312 has a dedicated high voltage input connector 364 for receiving ultrasonic signals from an ultrasonic power source. The multipoint controller unit 312 has a multi-channel distance input 356 for receiving analog distance information from ultrasonic probes connected to the multipoint controller unit 312.

[0025] The multipoint controller unit 312 may include a button 360 for quickly pairing the multipoint controller unit 312 with an ultrasonic power source. The multipoint controller unit 312 may incorporate a microcontroller 354. The microcontroller 354 may control which high voltage relays 350 are activated to provide ultrasonic power to a particular probe. The microcontroller 354 may interpret distance information received via a multichannel distance input 356 to control the welding process. The microcontroller 354 may be programmed and controlled via a USB port 358. The microcontroller 354 may communicate with the ultrasonic power source via one or more Ethernet ports 362.

[0026] 4A and 4B are perspective views of a multipoint controller unit 412 according to one embodiment of the present disclosure. The multipoint controller unit 412 has a housing with two Ethernet ports 362, a USB port 358, a multichannel range input port 356, a dedicated high voltage input connector 364, a power input port 440, a main power LED 442, an LED indicator 444, and an SHV port 352.

[0027] Since the power input port 440 is a separate power port for supplying power to electronic circuits in the multipoint controller unit 412 itself, the power port and the communication port of the multipoint controller unit 412 itself can be separated in contrast to the multiprobe controller unit 212 of Fig. 2. The multiprobe controller unit 212 receives power and performs communication via the customized cable 216.

[0028] A main power LED 442 may be provided as a visual indicator of the status of the local multipoint controller unit 412, specifically whether the local multipoint controller unit 412 is receiving power via the power input port 440. An LED indicator 444 may be provided as a visual indicator of which of multiple probes is selected to receive ultrasound power.

[0029] Replacing a multi-probe controller unit in a base and cassette style machine (e.g., base and cassette style machine 100) with a multi-point controller unit (e.g., multi-point controller unit 312) can provide an architectural change that has several advantages. FIG. 5 is a schematic diagram of a base and cassette style machine 500 with a multi-point controller unit 512 according to one embodiment of the present disclosure. The base and cassette style machine 500 includes a base 506 and a cassette 504. The base 506 includes a PLC 501, one or more ultrasound power supplies 502, one or more wires 522, one or more Ethernet cables 516, and one or more high voltage ultrasound cables 514. The cassette 504 includes a multi-point controller unit 512 and an ultrasound probe set 510.

[0030] The PLC 501 is connected to one or more ultrasonic power sources 502 via one or more wires 522. The wires 522-1, 522-2, ... 522-M can be industrial bus or discrete I / O connections that allow communication between the PLC 501 and each of the power sources 502-1, 502-2, ... 502-M. Ethernet cables 516-1, 516-2, ... 516-M allow communication between each of the ultrasonic power sources 502-1, 502-2, ... 502-M and the multipoint controller units 512-1, 512-2, ... 512-M. The cassette 504 has one or more ultrasonic power ports 518-1, 518-2, ... 518-M that can accept the wires 512-1, 512-2, ... 512-M. Cassette 504 also includes one or more RJ-45 couplers 520-1, 520-2, . . . 520-M that can receive Ethernet cables 516-1, 516-2, . . . 516-M.

[0031] Each probe set 510-1, 510-2, ... 510-M includes at least one probe. It is not necessary that each probe set 510-1, ... 510-M include the same number of probes. For example, probe set 510-1 may have eight probes while probe set 510-2 may have ten probes. Each probe in a probe set 510 includes a distance sensor that provides distance information. The distance information is carried on the sensor bus 508 from the individual probe sets 510 to the individual multipoint controller units 512. For example, if probe set 510-1 includes six probes, then distance information will be generated by each of the six probes and carried on the sensor bus 508-1 to the multichannel distance input port of the multipoint controller unit 512-1.

[0032] Comparing FIG. 5 with FIG. 2 reveals some architectural differences. In FIG. 5, PLC 501 is all digital and multipoint controller unit 512 is capable of processing analog information. In FIG. 2, PLC 201 with analog I / O cards is not all digital, but rather has custom analog I / O cards for processing analog information, and multi-probe controller 212 is all digital. In FIG. 5, multipoint controller unit 512 processes distance information provided by probe set 510, while in FIG. 2, PLC 201 with analog I / O cards processes distance information provided by probe set 210. Sensor bus 508-1, 508-2, ... 508-M is much shorter than sensor cable 208. Therefore, distance information can be provided to multipoint controller unit 512 much more quickly than PLC 501 with analog I / O cards due to the longer processing time in the I / O cards. Furthermore, because the distance information is an analog signal, the longer cables routed from cassette to base require electromagnetic shielding to protect the signal integrity of the distance information. By processing the distance information in the multipoint controller unit 512, wiring and electromagnetic requirements are reduced. Also, in the embodiment of FIG. 2, additional quick disconnects (e.g., quick disconnect 219) for analog distance sensors (e.g., analog distance sensor 210) are required between the base 206 and each cassette (e.g., cassette 204).

[0033] Due to these architectural changes, the role of PLC 501 during the welding process is different from that of PLC 201 with analog I / O card. PLC 501 notifies ultrasonic power supplies 502 via wire 522 that a selected probe in probe set 510 should be activated. The corresponding one of ultrasonic power supplies 502, i.e., the one responsible for the selected probe, updates a signal on a separate Ethernet cable 516 connected to the corresponding multipoint controller unit 512, causing the selected probe to be selected by logic in the separate multipoint controller unit 512.

[0034] The PLC 501 then sends a signal to the corresponding one of the ultrasonic power supplies 502 to start the welding cycle and then waits until the welding cycle is complete. Once the welding cycle is complete, the data from the corresponding one of the ultrasonic power supplies 502 can be read by the PLC 501. The welding process can then continue with a different probe output selection. There is no delay due to the PLC 501 since the PLC 501 is not responsible for monitoring the distance information and therefore the welding process can be controlled by the individual multipoint controller unit 512 which does monitor the distance information.

[0035] There are several advantages to the embodiments of the present disclosure. For example, Ethernet style communication eliminates the need for customized quick change connectors (e.g., quick change connector 220 and quick disconnect 219 in FIG. 2). Custom quick change connectors can be replaced with inexpensive off-the-shelf RJ-45 couplers (e.g., RJ-45 coupler 520 in FIG. 5). Using off-the-shelf shielded CAT-5 cables and eliminating customized cables can significantly reduce wiring costs. Using CAT-5 cables and RJ-45 couplers also reduces the risk of miswired signals. Using these cables and couplers also reduces the risk of improper cable shielding from customized cables. Because Ethernet communication uses differential signals and runs them over twisted pairs, the presence of high voltage signals that generate electronic noise has a fairly minor effect on the communication between the power source (e.g., ultrasonic power source 502 in FIG. 5) and the multipoint controller unit (e.g., multipoint controller unit 512 in FIG. 5) according to some embodiments of the present disclosure.

[0036] Ethernet hardware can be used with any communication protocol that is transparent to other protocols, such as TCP / IP, industrial automation protocols, etc. A multipoint controller unit with Ethernet can operate simultaneously with PLCs, ultrasonic power supplies, and other devices on the same physical network. Using custom Ethernet frames to transmit protocol data avoids conflicts with existing network protocols that may reside on the same physical network. The communication protocol also provides error checking that is not available with the discrete wiring presented in Figure 2.

[0037] The Ethernet style communication allows more feedback information about the status of the multipoint controller unit (e.g., multipoint controller unit 512-1 in FIG. 5) to be passed to the ultrasonic power supply (e.g., ultrasonic power supply 502-1) and vice versa, without the need for cumbersome and expensive cables (e.g., customized cable 216 in FIG. 2) that would require discrete connections. The Ethernet style communication supports port forwarding, allowing multiple multipoint controller units to be daisy-chained without the use of an external switch. This allows a network with multiple multipoint controller units and power supplies to use a single switch port to communicate with all of the multiple controller units.

[0038] 6 is a schematic diagram of a base and cassette style machine 600 with a multipoint controller unit 612 connected in a daisy chain configuration in accordance with one embodiment of the present disclosure. The base and cassette style machine 600 includes a base 606 and a cassette 604, with the base 606 including a PLC 601, one or more ultrasonic power supplies 602, and an Ethernet switch 630. The cassette 604 includes a multipoint controller unit 612 and a probe set 610. The probe set 610 includes a distance sensor that provides distance information to the multipoint controller unit 612 via a sensor bus 608. Ultrasonic power is provided to the probe set 610 by a high voltage ultrasonic cable originating from the ultrasonic power supply 602, but is not shown in FIG. 6.

[0039] PLC 601 (similar or identical to PLC 501) is connected to an Ethernet switch 630. Ultrasonic power sources 602-1, 602-2, ... 602-M are also connected to the Ethernet switch 630. RJ-45 couplers 620 of cassettes 604 are also connected to the Ethernet switch 630. Ethernet switch 630 facilitates communication between PLC 601 and each ultrasonic power source 602-1, 602-2, 602-3, ... 602-M. Ethernet switch 630 also facilitates communication between ultrasonic power sources 602-1, 602-2, 602-3, ... 602-M and multipoint controller units 612-1, 612-2, 612-3, ... 612-N.

[0040] The multipoint controller units 612-1, 612-2, 612-3, ... 612-N are arranged in a daisy chain configuration. In one embodiment, each multipoint controller unit 612-2, 612-3, ... 612-N is provided with at least two Ethernet ports to facilitate connection of the multipoint controller units in the daisy chain configuration. One or more Ethernet cables 632 are used to connect the multipoint controller units in the daisy chain configuration. The daisy chain configuration allows the RJ-45 coupler 620 of the cassette 604 to be shared between the multipoint controller units 612. As shown in FIG. 6, an Ethernet switch (e.g., Ethernet switch 630) in the machine base allows multiple power supplies to control multiple multipoint controller units 612 with a single base-to-cassette connection.

[0041] According to some embodiments, multiple ultrasound power sources and multiple multipoint controller units can exist on the same network without mutual interference. A specific multipoint controller unit can be paired with a specific power source. A power source can be paired with multiple multipoint controller units switching ultrasound signals in a daisy chain fashion to expand the total number of probe selections available for that power source. Figure 7A is a schematic diagram of a base and cassette style machine 700 with two multipoint controller units 712-3 and 712-4 paired with one power source 702-3 in accordance with one embodiment of the present disclosure.

[0042] The base and cassette style machine 700 includes a PLC 701 and three power supplies 702-1, 702-2, and 702-3. The PLC 701 and the three power supplies 702 are connected to an Ethernet switch 730. The Ethernet switch 730 is similar to the Ethernet switch 630 and facilitates communication between the three power supplies 702 and the PLC 701. The Ethernet switch 730 also facilitates communication between each of the three power supplies 702 and each of the multipoint controller units 712-1, 712-2, 712-3, and 712-4 via RJ-45 couplers 720. Each multipoint controller unit 712 controls the ultrasonic power provided to a probe set 710. The probe set 710 provides distance information to the multipoint controller unit 712 via a sensor bus 708. As in FIG. 6, the multipoint controller units 712 are daisy-chained using Ethernet cables 732.

[0043] To provide ultrasound power to the probe set 710, the power supply 702 has a high voltage connection via wire 714 to the multiport controller unit 712. Power supply 702-1 is connected to the multipoint controller unit 712-1 via wire 714-1 and power port 718-1. Power supply 702-2 is connected to the multipoint controller unit 712-2 via wire 714-2 and power port 718-2. Power supply 702-3 is connected to the multipoint controller unit 712-3 via wire 714-3 and power port 718-3. Power supply 702-3 is also connected to the multipoint controller unit 712-4 via a daisy chained power configuration between the multipoint controller units 712-3 and 712-4. This daisy-chained power configuration allows ultrasonic power to flow from power supply 702-3 to multipoint controller unit 712-3, and from multipoint controller unit 712-3 via wires 734 to multipoint controller unit 712-4.

[0044] In Figure 7A, power supply 702-3 can provide ultrasonic power to probe sets 710-3 and 710-4. Power supply 702-3 also communicates with both multipoint controller units 712-3 and 712-4 via RJ-45 coupler 720. Thus, power supply 702-3 can be paired with multiple multipoint controller units 712. Although one-to-two pairing is shown as an example in Figure 7A, one power supply can be paired with more than two multipoint controller units.

[0045] Similar to Figure 7A, Figure 7B is a schematic diagram of a base and cassette style machine 700 with two multipoint controller units 712-3 and 712-4 paired with one power supply 702-3 according to one embodiment of the present disclosure. Instead of using a daisy chain configuration as in Figure 7A, Figure 7B uses a high voltage T-branch 736 to split the ultrasound power from power supply 702-3. High voltage T-branch 736 acts as a power splitter so that power supply 702-3 can provide power through multipoint controller unit 712-3 to probe set 708-3 and also through multipoint controller unit 712-4 to provide power to probe set 708-4.

[0046] There are several advantages to the embodiments of the present disclosure: Multi-channel analog inputs are located on the multipoint controller unit (e.g., multipoint controller unit 712 in FIG. 7A), allowing welding using distance or position sensors without the need for costly analog I / O cards for PLCs. In base and cassette style machines, the multipoint controller unit can typically be located close to the ultrasonic probe, so having analog distance inputs on the multipoint controller unit significantly reduces machine wiring costs and electrical noise induction risks.

[0047] By providing an analog distance input to the multipoint controller unit, the distance traveled by the distance information from the analog distance sensor is reduced. This allows welding using the distance information to be much more accurate, since the sampling rate in the multipoint controller unit is much higher than in most PLCs. The rate at which the distance information from the analog distance sensor can be sampled in the PLC can be affected by the scan time, which is determined by the processor speed, the number of program steps, the number of I / Os, etc. The accuracy of the trigger position that starts the welding process, as well as the accuracy of the welding end position or distance, are directly affected by the scan time. Scan times in modern PLCs are often from a few milliseconds to as much as 20 ms.

[0048] The Ethernet cable communication protocol can be custom designed for the multipoint controller units to provide custom frames with messages specific to the multipoint controller units. The communication protocol allows the power supplies to be remotely paired with the multipoint controller units to form a master-slave control relationship that is protected from external influences using a shared secret established during the pairing operation. The pairing operation creates a logical control channel between the individual power supplies and the individual multipoint controller units, thereby emulating discrete physical I / O. The physical network topology between the paired multipoint controller units and power supplies can be changed without affecting the logical connections. That is, for example, ultrasonic power supplies 602-2 and 602-3 are logically paired with corresponding ones of multipoint controller units 612-2 and 612-3, and the positions of the multipoint controller units 612-2 and 612-3 are swapped in the daisy chain. Although a change has occurred in the physical configuration of the multipoint controller units 612-2 and 612-3, the multipoint controller units 612-2 and 612-3 will maintain their pairing logical connections to their corresponding ones of the power sources 602-2 and 602-3.

[0049] The communication protocol can support both a simple, tool-free "one button" pairing operation as well as a more comprehensive operation using a personal computer (PC) utility. The "one button" pairing operation can be used for rapid field replacement of known defective units. The PC utility supported operation can provide detailed pairing status and system identification information (e.g., model number, serial number, firmware version) that is useful for debugging tasks. Both the "one button" pairing option and the PC utility option are simpler than any PLC development tool, allowing for a lower training level for maintenance personnel than may be required for PLC-based networks.

[0050] According to one embodiment, each multipoint controller unit (e.g., multipoint controller unit 612) can be in one of three states with respect to its communications protocol. The three states include an unpaired state ("UNPAIRED" state), a paired but unconnected state ("UNCONNECTED" state), and a paired and connected state ("CONNECTED" state). Real-time control and status information is only exchanged in the CONNECTED state. Each paired multipoint controller unit must be in the CONNECTED state before it is operational.

[0051] According to an embodiment, a paired multipoint controller unit (e.g., multipoint controller unit 612) can detect improper wiring of the high voltage ultrasonic cable between the power source and the multipoint controller unit. For example, when a multipoint controller unit 612-2 is paired with an ultrasonic power source 602-1, the multipoint controller unit 612-2 is in communication with the ultrasonic power source 602-1. During a welding process, if the ultrasonic power source 602-1 indicates that it is providing ultrasonic power to the multipoint controller unit 612-2, but the multipoint controller unit 612-2 is not receiving any ultrasonic power at its ultrasonic power input (e.g., ultrasonic power input 364), the multipoint controller unit 612-2 can provide a signal to stop the power delivery from the ultrasonic power source 602-1. The multipoint controller unit 612-2 can sense that the ultrasonic power output from the power source 602-1 is not properly wired to its own multipoint controller unit 612-2.

[0052] Using a multipoint controller unit according to embodiments of the present disclosure in a base and cassette style machine, distance information can be used to start and stop a weld. According to some embodiments, the distance information can be used to determine the quality of the weld. Figure 8 is a flow diagram illustrating a welding process using a multipoint controller unit (e.g., multipoint controller unit 612-1) according to an embodiment of the present disclosure. In step 802, the multipoint unit is paired with a power source. For example, the multipoint controller unit 612-1 is paired with the power source 602-1 using "one button" pairing or PC utility pairing according to embodiments of the present disclosure.

[0053] In step 804, the multipoint controller unit 612-1 monitors distance information received from the selected probe in the probe set 610-1. In step 806, the multipoint controller unit 612-1 determines from the distance information whether a trigger position has been reached. The trigger position is the distance that separates the selected probe from a particular location on the part being welded. The probes or parts continue to be moved until the trigger position is reached. If the trigger position has not been reached, the distance information is monitored in step 804. A triggered by power method could also be used to initiate ultrasonic welding.

[0054] Once the trigger position is encountered, the multipoint controller unit 612-1 sends a signal to the power supply 602-1 to deliver ultrasound power to the selected probe to the multipoint controller unit 612-1 in step 808. This signal is sent over Ethernet by the Ethernet switch 630.

[0055] When power is being delivered, distance information from the selected probe in probe set 610-1 is monitored. When the part is being welded, the target collapse distance is checked in step 812. If the target collapse distance has not been reached, the distance information continues to be monitored in step 810.

[0056] Once the target disruption distance has been reached, the multipoint controller unit 612-1 sends a signal to the power supply 602-1 to stop delivering ultrasonic power to that multipoint controller unit 612-1, step 814. This signal is sent over the Ethernet by the Ethernet switch 630.

[0057] The multipoint controller unit 612-1 may send data about the welding process to the power source at step 816. This data may include the quality status of the weld completion.

[0058] Although the present disclosure has been described with reference to one or more specific embodiments and implementations, those skilled in the art will recognize that many modifications may be made thereto without departing from the spirit and scope of the present disclosure, and all such embodiments and implementations, and obvious variations thereof, are deemed to fall within the spirit and scope of the present disclosure, as set forth in the following patent description.

Claims

1. A system for supplying power to a plurality of ultrasonic welding probes from M power sources, comprising: N multipoint units, each of the N multipoint units having Housing and a plurality of analog or digital inputs configured to carry distance information relating to the probing distances of a plurality of ultrasonic welding probes; a dedicated high voltage input connector connectable to a dedicated high voltage output connector of one of the M power sources via a high voltage cable; At least one Ethernet port, A microcontroller, directing power from the dedicated high voltage input connector to corresponding ones of the plurality of ultrasonic welding probes; and sampling the distance information of the plurality of ultrasonic welding probes at a rate of at least once per millisecond; A microcontroller configured Including, The system further comprises: a base housing the M power sources, where M and N are both integers equal to or greater than 1; each of the N multipoint units being interconnected by Ethernet to form a network having the N multipoint units and the M power sources as components thereof, whereby (i) each of the N multipoint units is paired with a different one of the M power sources in the network to avoid interference between any of the N multipoint units and any of the M power sources; (ii) a first one of the N multipoint units is paired with a first one of the M power sources in the network; the microcontroller of the first one of the N multipoint units; receiving a signal from the first one of the M power sources over the network indicating that the first one of the M power sources is providing power to the dedicated high voltage input connector of the first one of the N multipoint units; detecting a power level at the dedicated high voltage input connector of the first one of the N multipoint units; generating an error signal for the first one of the M power sources to stop providing power in response to the detected power level falling below a threshold; It is composed of system.

2. 2. The system of claim 1, wherein a first multipoint unit of the N multipoint units further comprises a button configured to form a pairing between the first multipoint unit and a first one of the M power sources.

3. 2. The system of claim 1, wherein a first multipoint unit of said N multipoint units further comprises a Universal Serial Bus (USB) port.

4. 2. The system of claim 1, wherein the pairing between the first one of the M power sources and the first one of the N multipoint units creates a logical control channel between them, such that physical changes in the physical topology of the network do not disrupt the logical control channel between the first one of the M power sources and the first one of the N multipoint units.

5. 2. The system of claim 1, wherein the N multipoint units and the M power sources communicate according to a custom communication protocol that supports pairing operations and enables the exchange of control status and information.

6. 6. The system of claim 5, wherein the at least three states for a first multipoint unit of the N multipoint units include a first state indicating that the first multipoint unit is not paired with any of the M power sources, a second state indicating that the first multipoint unit is paired with a first power source of the M power sources but not connected to the first power source, and a third state indicating that the first multipoint unit is paired with the first power source and connected to the first power source.

7. 2. The system of claim 1, further comprising: The system includes an Ethernet switch configured to physically interface the N multipoint units with a programmable logic controller (PLC).

8. 8. The system of claim 7, the at least one Ethernet port of each of the N multipoint units being at least two Ethernet ports; The system wherein the Ethernet switch is further configured to accept N Ethernet cables from the N multipoint units.

9. 8. The system of claim 7, the at least one Ethernet port on each of the N multipoint units is at least two Ethernet ports; the Ethernet switch is further configured to interface the M power sources with the N multipoint units, and the N multipoint units are arranged in the network in a daisy chain manner such that the Ethernet switch accepts one Ethernet cable from one of the N multipoint units.

10. 2. The system of claim 1, wherein the microcontroller in a first one of the N multipoint units further comprises: comparing distance information of corresponding ones of the plurality of ultrasonic welding probes to determine whether the distance information indicates that a threshold has been violated; generating an error signal and stopping the welding process if said threshold value is violated; The system being configured.

11. 11. The system of claim 10, wherein the error signal is generated after the welding process has begun.

12. 1. A method for providing power from a first power source of M power sources to a plurality of ultrasonic welding probes coupled to a first multipoint unit of N multiport units, comprising: pairing the first multipoint unit with the first power source, wherein each of the N multipoint units has at least one Ethernet port for connecting the N multiport units to the M power sources in a network; receiving distance information relating to the probe distances of the plurality of ultrasonic welding probes via the plurality of analog or digital inputs of the first multipoint unit; a dedicated high voltage input connector of the first multipoint unit, the dedicated high voltage input connector being connectable via a high voltage cable to a dedicated high voltage output connector of the first power source to receive power from the first power source; directing the power from the first power source to corresponding ones of the plurality of ultrasonic welding probes in response to a microcontroller in the first multipoint unit; sampling the distance information of the corresponding ones of the plurality of ultrasonic welding probes at a rate of at least once per millisecond under the control of the microcontroller; the microcontroller comparing the sampled distance information to determine whether a threshold has been violated; the microcontroller generates an error signal to stop the initiation of the welding process upon the threshold being violated, the error signal being generated before the welding process begins. It is a method, The method wherein M and N are both integers of 1 or greater.

13. 13. The method of claim 12, further comprising, prior to pairing the first multipoint unit with the first power source, receiving a pairing signal from a button on the first multipoint unit, and initiating the pairing between the first multipoint unit and the first power source according to the pairing signal.

14. 13. The method of claim 12, wherein pairing the first multipoint unit with the first power source is performed by either one button pairing or computer utility pairing.

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