Patent Application
20120097644
The present invention relates generally to the field of welding systems, and more particularly to welding systems adapted for remote control of welding parameters.
A wide range of systems have been developed and are presently in use for performing welding operations. In general, such devices may be based upon specific technologies and system designs, including metal inert gas (MIG), tungsten inert gas (TIG), stick, and so forth. All of these techniques require a power supply for operation. In such arc welding processes, a power circuit is developed between an electrode and a workpiece, and a resulting arc serves to heat filler metal, base metal or both.
In many welding applications a number of parameters may be modified by user selection on a faceplate or panel on a welding power supply. Such parameters may include selection of a process, selection of currents and voltages, selection of wire feed speeds, and so forth. In some processes the power supply is coupled directly to leads that are used for the welding operation. However, in many applications, such as MIG welding, leads are coupled between the power supply and a wirefeeder which spools electrode wire that serves as a filler metal during the welding operation. Many power supplies and wirefeeders are equipped to exchange data, which is typically done by a control cable separate from the weld cable that is connected between data pins on the power supply and corresponding pins on the wirefeeder. Low level power and data signals may be transmitted over the control cable such that feedback may be provided from the wirefeeder, commands can be exchanged between the devices, and in some cases weld parameters may be set remotely on the wirefeeder which may be positioned at some distance from the power supply, closer to the actual location where a welding operation is being performed.
Improvements have been made in these systems wherein data signals may be superimposed on power signals. That is, data that could be transmitted via a separate control cable may be superimposed on weld power transmitted between the welding power supply and the wirefeeder. Systems of this type allow for fewer cables extending between the power supply and the wirefeeder, and may greatly facilitate certain operations, particularly where the wirefeeder is positioned at a considerable distance from the power supply. A current problem in the field, however, results from the incompatibility of many power supplies with wirefeeders designed for use with power supplies that are capable of transmitting data and welding power over the same cable. That is, while wirefeeders and power supplies work well together when both equipped to modulate and de-modulate data over welding power, these improved wirefeeders may not function with conventional power supplies that are designed to transmit data over a separate control cable. There is a need, therefore, for an improved system that will allow for such compatibility.
There present invention provides a novel welding system designed to respond to such needs. The system may be used in a wide range of settings, but is particularly well-suited to applications in which a welding power supply and a wirefeeder are used at some considerable distance from one another. The invention is well-suited to applications where a power supply is incapable of combining data with welding power, but a wirefeeder is capable of separating data from welding power signals. The invention therefore provides back compatibility for many thousands of power supplies that would not otherwise be capable of operating with such wirefeeders. The invention is particularly attractive for operations that may have a suite of wirefeeders that may now operate with both more sophisticated power supplies (capable of combining data with welding power) and more conventional welding power supplies.
In accordance with one aspect of the invention, a welding system comprises a welding power connection configured to receive welding power from a welding power supply via a weld cable, a control signal connection configured to exchange welding operation data with the welding power supply via a signal cable, and a wirefeeder connection configured both to send welding power from the welding power supply to a wirefeeder and to exchange welding operation control data with the wirefeeder over a wirefeeder cable. A communication circuit configured to combine the welding power from the welding power supply and data from the power supply for application to the wirefeeder connection, and to separate data from the wirefeeder connection for communication to the control signal connection.
The invention also provides a welding system that comprises a welding power supply configured to provide welding power suitable for a welding operation, and a wirefeeder configured to receive the welding power and to provide the power along with welding wire for the welding operation. A controller is coupled between the welding power supply and the wirefeeder, and comprises a welding power connection configured to receive welding power from the welding power supply via a weld cable, a control signal connection configured to exchange welding operation data with the welding power supply via a signal cable, a wirefeeder connection configured both to send welding power from the welding power supply to a wirefeeder and to exchange welding operation control data with the wirefeeder over a wirefeeder cable, and a communication circuit configured to combine the welding power from the welding power supply and data from the power supply for application to the wirefeeder connection, and to separate data from the wirefeeder connection for communication to the control signal connection.
In accordance with another aspect of the invention, a welding system comprises a welding power supply configured to provide welding power suitable for a welding operation, the welding power supply being incapable of combining data signals with welding power signals. A wirefeeder is configured to receive the welding power and to provide the power along with welding wire for the welding operation, the wirefeeder being capable of extracting data signals from welding power signals. A controller is coupled between the welding power supply and the wirefeeder, the controller. The controller is configured to receive welding power and separately transmitted data signals from the welding power supply, and to combine the welding power and separately transmitted data signals for transmission to the wirefeeder.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Turning now to the drawings, and referring first to
In the embodiment illustrated, the power supply 12 may be a conventional power supply that ordinarily provides welding power for a welding operation, while exchanging data with a wirefeeder via a separate control or data cable. Such cables may be configured in accordance with standards in the industry, with many such cables having connectors suitable for interfacing with multi-pin receptacles on the power supply 12 and on a conventional wirefeeder. The illustrated wirefeeder 16, however, is designed to provide data and power signals over the same cable, or in practice, to separate data from welding power provided by the power supply, and to combine data over the same conductor for sending back to a power supply. However, the power supply 12 is not designed either to combine data with welding power signals or to extract data from such welding power signals. Accordingly, the external control module 14 is provided to serve as an interface between these two system types.
In a presently contemplated embodiment, power supply 12 may be of the type available commercially from Miller Electric Mfg. Co. of Appleton, Wis. under the designation XMT 350 CC/CV. The wirefeeder 16, on the other hand, may be of the type commercially available from the same company under the designation Suitcase X-treme 8VS, WCC and Suitcase X-treme 12VS, WCC Other models and system types may, of course, be employed. The latter device is specifically designed in conformance with a technique sometimes referred to in the field as weld control cable (WCC) according to which a wirefeeder may allow welding operators to control certain welding parameters, such as voltage, at the wirefeeder, eliminating the need to travel to the power source for parameter adjustments. WCC-enabled devices, however, allow for connection between a WCC-enabled power supply and a WCC-enabled wirefeeder. The external control module 14, then, allows for back compatibility between WCC-enable wirefeeders and non-WCC-enabled power supplies.
In the illustrated embodiment, the power supply 12 has a front panel 18 which may permit adjustment of certain welding parameters. Depending upon the design of the power supply, such welding parameters may include selection of a welding operation, currents and voltages, and so forth. It should be noted that the provision of the external control module 14 allows for interoperability between a wide range of power supplies (i.e., sized, configurations, types) designed for different applications, where the power supplies are not WCC-enabled. Such capabilities will greatly expand the number of power supplies that can be operated with a WCC-enabled wirefeeder. Regardless of the power supply design, power supply 12 is equipped with a weld cable connection 20 and a workpiece cable connection 22. In certain operations, weld cables and workpiece cables may be coupled directly to these connections for performing a welding operation in the vicinity of the power supply. A control signal connection 24 is provided which, again, may consist of a multi-pin connector for providing data, receiving data, and providing low-level power where desired. The control signal connection 24, in conventional systems, may be used to communicate with a non-WCC-enabled wirefeeder in a conventional manner. However, in the present invention, the control signal connection 24 will be coupled to the external control module 14 and described below.
The power supply weld cable connection 20 is designed to receive a weld cable 26 and a workpiece cable 28 that extend between this power supply and the external control module 14. A control cable 30 is then coupled between the external control module 14 and the control signal connection 24 of the power supply. Thus, the external control module 14 receives weld power and may exchange data with the power supply 12 as would a conventional wirefeeder connected to the power supply. The weld cable 26, workpiece cable 28 and control cable 30 may be considered the inputs to the external control module 14. Outputs of the module are provided by a wirefeeder cable 32 that extends between the external control module and the wirefeeder, and a workpiece cable 34. In many applications, the workpiece cable 34 will terminate in a clamp 36 designed to be clamped to a workpiece. The wirefeeder 16 receives weld power and data via the cable 32 and provides weld power output via a weld cable 38 which will typically terminate in a welding torch 40. In the illustrated embodiment, the system further comprises a sensing cable 42 which may be coupled to the workpiece, and a torch trigger receptacle 44. For MIG welding, the wirefeeder may also be coupled to a gas cylinder 46 to provide desired shielding gas. As will be appreciated by those skilled in the art, depending upon the type of wire supplied in the wirefeeder 16, such welding gas may not be required.
With the arrangement shown in
The external control module 14 comprises a power supply circuitry 70 and a weld cable communication interface 72. The power supply circuitry 70 is coupled to the remote receptacle 68 via the multi-conductor control cable. The power supply circuitry provides signals to the weld cable communication interface 72 which itself serves to combine data signals onto the welding conductors as indicated by reference numerals 26 and 28 which are output via cables 32 and 34. The weld cable communication interface 72 also serves to extract data from the welding power on these conductors for providing command and/or feedback to the remote receptacle 68 and therethrough to the control circuitry 62. As noted above, the weld cable communication interface 72 may use a range of communication and signal modulating protocols, such as Echelon LonWorks™ Powerline Communications (PL-22), a narrow-band BPSK modulated carrier. Moreover, the operation of the external control module and wirefeeder may conform to the functionality set forth in the following U.S. patent applications, all of which are incorporated into the present disclosure by reference: U.S. patent application Ser. No. 11/625,357, entitled Method and System for a Remote Wire Feeder where Standby Power and System Control are Provided via Weld Cables, filed on Jan. 22, 2007 by Ott; U.S. patent application Ser. No. 11/276,288, entitled Remote Wire Feeder using Binary Shift Keying to Modulate Communications of Command/Control Signals to be Transmitted over a Weld Cable, filed on Feb. 22, 2006 by Ott; U.S. patent application Ser. No. 11/609,871, entitled Remote Wire Feeder using Binary Shift Keying to Modulate Communications of Command/Control Signals to be Transmitted over a Weld Cable, filed on Dec. 12, 2006 by Ott et al.
As further illustrated in
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.
