Patent Description:
A power supply is a basic part of a welding apparatus in that it is configured to supply the necessary electric arc that is critical to welding. Depending on the method of electric welding, the power supply may deliver electric power according to different parameters. An output voltage of a welding power supply is set to levels defined by the needs of the welding method selected, safety requirements and an effectiveness of the apparatus. As a rule, a maximum voltage output by the power supply is far too low to cause electric breakdown from a working electrode to a workpiece at usual operating distances. Therefore, the start of welding operation may commence in a "contact" manner. That is, the welding is initiated upon direct contact of a working electrode and the workpiece. After an activation of the power supply, when a certain current flows out of the power supply, an arc is ignited between the electrode and the workpiece. Alternatively to the contact method, welding may begin without contact between the electrode and the workpiece. In this alternative case, the welding apparatus comprises an auxiliary device, which, for a short time, delivers a high frequency increased voltage sufficient to cause electric breakdown between the electrode and the workpiece and thus start the electric arc and the welding process.

In view of the different possible states of the welding process, it is often desirable to monitor and track various parameters such as voltage, current, and/or any number of other welding or associated parameters.

<CIT> (basis for the preamble of claims <NUM> and <NUM>) discloses systems and methods of communicating between a welding power source and a welding wire feeder to improve the operation of a welding system.

According to a first aspect of the present invention there is provided a connector and sensor unit for a welding apparatus as recited in claim <NUM>.

According to a second aspect of the present invention there is provided a method as recited in claim <NUM>.

<FIG> depicts a block diagram of an arrangement for a welding apparatus, including a connector and sensor unit <NUM>, and a loopback connection, in accordance with an example embodiment. As shown in the figure, mains power supply <NUM> supplies electric power to welding power source <NUM>. Welding power source <NUM> may also be referred to herein as a welding "power supply" <NUM>. Power supply <NUM> provides connections for two cables or leads <NUM> and <NUM>, respectively providing plus and minus welding voltages. These cables may also be referred to herein as "first" and "second" welding cables, and the "first" welding cable may be the plus welding voltage cable or the minus voltage welding cable, and the "second" welding cable would then be the other of the plus or minus voltage welding cable. For ease of description, the "plus" and "minus" voltage cable or lead terminology is employed herein, but those skilled in the art will appreciate that such terminology should not be considered to limit the scope of the invention. For example, the respective welding cables may deliver AC welding power and, as such, "plus" and "minus" designations may not have any particular relevance. The plus voltage cable <NUM> may be connected to a welding torch <NUM>. The minus voltage cable <NUM> may be connected to a workpiece <NUM> via a connector and sensor unit <NUM>, which, at a high level, provides selected power supply sensing functions and connectivity to a communications unit <NUM>, via cable <NUM>, that enables wireless communication with, e.g., a mobile device <NUM> and/or a remote or cloud server <NUM>. In the embodiment of <FIG>, loopback connection <NUM> (discussed later herein) provides a plus voltage signal to connector and sensor unit <NUM> such that plus voltage cable <NUM> does not itself need to pass through connector and sensor unit <NUM>.

In an alternative embodiment, as shown in <FIG>, loopback connection <NUM> is eliminated, and plus voltage cable passes through connector and sensor unit 200B.

The connector and sensor unit <NUM> derives power from plus and minus leads <NUM>, <NUM> of welding power supply <NUM>. That is, one function of the connector and sensor unit <NUM> is to provide a steady, e.g., <NUM> volt DC, supply of power to power circuitry within the connector and sensor unit <NUM>, and to power, at least, circuitry within communications unit <NUM> so that, together, the connector and sensor unit <NUM> and communications unit <NUM> can perform measurement, calculation, storage, compilation and/or communication functions. An issue with obtaining power from the welding cables <NUM>, <NUM>, however, is that a voltage between those cables may be on the order of <NUM>-<NUM> volts and there might also be, periodically, high frequency (HF) and high voltage (HV) signals that are used for arc ignition. In bleeding power away from welding cables <NUM>, <NUM>, it is important not to disrupt or otherwise distort the voltage signals on welding cables <NUM>, <NUM> as such distortion may detrimentally impact the ability of the welding apparatus to achieve the desired welding functionality (e.g., arc ignition).

As will be explained further below, connector and sensor unit <NUM> is connected to welding cables <NUM>, <NUM> via inductors (operating as RF chokes) to ensure that, e.g., HF high voltage signals that might be present on the leads <NUM>, <NUM>, and that are meant to be applied at the torch worksite, are not problematically impacted.

The connector and sensor unit <NUM> senses or monitors several parameters regarding the state of welding power supply <NUM> (as well as other possible parameters) and, via link <NUM>, passes signals indicative of the sensed states to communications unit <NUM>. The signals may be provided in analog or in digital and/or packetized form. Communications unit <NUM> may then (digitize/packetize and) share that information with applications running on mobile device <NUM> and/or cloud server <NUM>. Communications unit <NUM> may communicate with mobile device <NUM> and/or cloud server <NUM> via well-known short range wireless communication protocols such as Bluetooth™ or wireless fidelity (WiFi), or well-known cellular communication standards.

In an embodiment, connector and sensor unit <NUM> is provided with an Internet Protocol (IP) address that is associated with cloud server <NUM>. The IP address may be supplied by a user, via, e.g., mobile device <NUM>, to communications unit <NUM>. Data collected by connector and sensor unit <NUM> and supplied to communications unit <NUM> may then be transmitted to cloud server <NUM>, via an internet connection, for storage and analysis. The amount of data stored with respect to each weld may be dependent on how much information is entered by a user, and a number of sensors attached to, or are provided within, the connector and sensor unit <NUM>. A welding time may also influence the amount of data created and stored. In one implementation, after each weld (or during a given welding operation), measured values (e.g., one or more values per second) together with entered information provided prior to welding (e.g., entered via mobile device <NUM>) is automatically sent to the cloud server <NUM>.

In an embodiment, each connector and sensor unit <NUM> has a unique identification number and/or serial number (that it is selected, e.g., at manufacturing). That identification information may be sent along with any data to ensure that data associated with a given welding machine or user is kept together. An application on mobile device <NUM> may be configured to receive still other user inputted information that can be bundled together with measured data for each weld and stored in the cloud server <NUM>. Examples of such other information include welding equipment, power source, wire feeder type, welder, work object or workpiece, type of weld joint, and weld seam in a multi-seam weld joint, among other possible information. Cloud server <NUM> may respond back to mobile device directly, or via communications unit <NUM>, with, e.g., work tips, or other feedback regarding welding, maintenance, etc..

<FIG> depicts a perspective drawing of the connector and sensor unit <NUM> in accordance with an example embodiment. In <FIG>, connector and sensor unit <NUM> may comprise a metal or hard plastic enclosure <NUM> that is configured to withstand typical welding shop environment handling. Connector and sensor unit <NUM> includes several ports through which, and from which, electrical (analog or digital) signals can pass. Reference may also be made to <FIG>, which depicts a more detailed arrangement for a welding apparatus in accordance with an example embodiment including connector and sensor unit <NUM>.

In the depicted embodiment of <FIG>, which should not be construed as limiting, towards the upper left side of the figure there are two ports (not visible in <FIG>, but visible in <FIG>). One port receives the plus power supply welding voltage from the power supply <NUM> via loopback connection <NUM>, and the other port is arranged with a coupler to output the minus supply voltage <NUM> that is to be connected to a workpiece.

The visible ports in <FIG> towards the right hand side of the drawing include a port to receive the minus supply welding voltage <NUM> from the power supply <NUM>, a port <NUM> to receive a wire feeder encode signal, and a port <NUM> to output several signals to the communications unit <NUM>. Port <NUM> may be a multi-pin port to accommodate multiple different signals and a power supply.

<FIG> depicts a perspective drawing of a connector and sensor unit 200B through which the welding cables <NUM>, <NUM> pass in accordance with an example embodiment. <FIG> is consistent with <FIG> where loopback connection <NUM> is eliminated.

The description hereafter focuses primarily on the embodiments depicted in <FIG> and <FIG>, i.e., the embodiments including loopback connection <NUM>. However, those skilled in the art will appreciate that the features described hereinafter may be equally applicable to the embodiments depicted in <FIG> and <FIG>.

As noted, <FIG> depicts a more detailed arrangement for a welding apparatus in accordance with an example embodiment. <FIG> shows, practically, how the connector and sensor unit <NUM> is connected to the power supply <NUM> and communications unit <NUM>. It is noted that <FIG> depicts an arrangement for a MIG (metal inert gas) welding process, but the embodiments described herein are applicable to other welding processes as well, including, but not limited to, TIG (tungsten inert gas) welding, and stick welding processes. As shown, connector and sensor unit <NUM> is configured to receive power supply <NUM> minus voltage cable <NUM> and pass the minus voltage signal to an output port. As is seen in <FIG>, in accordance with one possible implementation, minus voltage cable <NUM> is used to sense the amount of current being drawn or supplied by power supply <NUM>. Connector and sensor unit <NUM> also receives the plus voltage from the power supply <NUM> via a loopback cable <NUM> connected to plus voltage cable <NUM>. In the embodiment in which plus voltage cable <NUM> passes through the connector and sensor unit 200B, plus voltage cable <NUM> could alternatively be used to sense the amount of current being drawn or supplied by power supply <NUM>.

A wire feeder <NUM> is also shown in <FIG>. In accordance with one embodiment, a separate wire feeder encoder <NUM> is provided and through which welding wire is passed to monitor, e.g., wire speed or wire amount used. In the embodiment shown in <FIG>, cable <NUM> supplies a wire feeder encoder signal from the wire feeder encoder <NUM> to the wire feeder encode signal port <NUM> of connector and sensor unit <NUM>. Cable <NUM> may also supply power to the wire feeder encoder <NUM> that is generated within connector and sensor unit <NUM>.

Finally, cable <NUM> is used to connect output port <NUM> on connector and sensor unit <NUM> and communications unit <NUM>. Cable <NUM> is used to carry signals indicative of one more states of parameters related to the power supply <NUM>, among other possible signals, and to provide power to communications unit <NUM>. In an embodiment, communications unit <NUM> is mounted on power supply <NUM> via magnets, hook and loop tape or a strap. Since the communications unit <NUM> includes a radio transmitter/receiver, it is advantageous to position the communications unit <NUM> as high as practicable. In an embodiment, communications unit <NUM> includes a rechargeable battery or charge capacitor (not shown), which is recharged by power supplied by connector and sensor unit <NUM>. Such a battery or charge capacitor (power storage device) enables the communications unit <NUM> to operate, at least for a period of time, even when no power is supplied from power supply <NUM>.

Also shown in <FIG> are a gas bottle <NUM> that feeds appropriate gas to torch <NUM> and wire <NUM> that is being fed from wire feeder <NUM>. Still also shown in <FIG> are mobile device <NUM> and cloud server <NUM>. In one embodiment, communications unit <NUM> communicates received information from connector and sensor unit <NUM> to mobile device <NUM> via, e.g., Bluetooth, and/or to cloud server <NUM> via WiFi (or mobile telephony protocols).

<FIG> depicts a block diagram of circuitry that may be deployed in the connector and sensor unit <NUM> in accordance with an example embodiment. As shown, connector and sensor unit <NUM> includes three inputs and two outputs, in the example embodiment. The inputs include ports for the plus and minus welding voltages via cable <NUM> and loopback <NUM>, and wire feeder encoder signal via cable <NUM> and port <NUM>. The outputs include the minus welding voltage <NUM> and a plurality of signals available at port <NUM>. Those skilled in the art will appreciate that more or fewer ports may be provided in connector and sensor unit <NUM>. Also, for simplicity, only one signal wire is shown being output for each of the several components <NUM>, <NUM>, <NUM>, <NUM> described below, but those skilled in the art will appreciate that each output might also include a corresponding ground signal, or might include still other associated wires/signals.

Circuitry that generates the plurality of signals available at port <NUM> is described below. Current sensor circuitry <NUM> is provided to sense an amount of current flowing through welding cables <NUM>, <NUM> by using a current sensor <NUM> that encircles, e.g., minus welding voltage cable <NUM> (or, possibly, the plus welding voltage cable <NUM> in the non-loopback connection embodiment). A signal from current sensor <NUM> is supplied to current sensor circuitry <NUM> which outputs a corresponding current sense signal <NUM>, which may be a voltage signal indicative of the amount of current flowing in the cable <NUM>.

Wire feeder encoder signal conditioning circuitry <NUM> receives the wire feeder encoder signal and applies appropriate normalization, or voltage conditioning, and outputs a corresponding conditioned wire feeder encoder signal <NUM>. Wire feeder encoder signal conditioning circuitry <NUM> may, for example, include optical isolation circuitry to isolate the input and output thereof.

Voltage sensing circuitry <NUM> senses the voltage between plus and minus welding cables <NUM>, <NUM> and outputs a corresponding voltage sense signal <NUM>.

Supply power circuitry <NUM> receives power from the plus and minus welding voltages <NUM> (<NUM>), <NUM> and converts the same to, e.g., a <NUM> volt DC voltage. That DC voltage is used within connector and sensor unit <NUM> (i.e., the voltage provides power to, e.g., current sensor circuitry <NUM>, wire feeder encoder signal conditioning circuitry <NUM>, and/or voltage sensing circuitry <NUM>) and is also output as power supply voltage <NUM> that is supplied to communications unit <NUM> so that communications unit <NUM> has the necessary power to operate. Power supply voltage <NUM> may also be supplied to cable <NUM> to power wire feeder encoder <NUM>. By generating and supplying power from the welding voltages, power is available within connector and sensor unit <NUM> and can be made available to the wire feeder encoder <NUM>, and the communications unit <NUM> to recharge a battery therein.

In one embodiment, signals <NUM>, <NUM>, <NUM> and voltage supply <NUM> are provided directly to communications unit <NUM>, without further processing, e.g., in an analog format.

In another embodiment, processor <NUM> and memory <NUM> may also be provided and used to, e.g., generate, and/or process, e.g., signal <NUM>, <NUM>, and/or <NUM> prior to transmitting the same to communications unit <NUM>. More specifically, memory <NUM> may be used to store logic instructions (e.g., software or firmware) that, when executed by processor <NUM>, enable any of the circuitry shown in the connector and sensor unit <NUM> to be configured or operated. The software or firmware (or adequate hardware circuits) can also be used to analog-to-digital convert, bundle and/or packetize one or more of the several signals, generated by connector and sensor unit <NUM>, with, e.g., identification information of the connector and sensor unit <NUM>. Resulting bundles of data or packets may then be passed to communications unit <NUM> via port <NUM>. In one embodiment, connector and sensor unit <NUM> may include a user interface, e.g., a display (not shown), and processor <NUM> and memory <NUM> may execute/store instructions that enable the user interface to provide information to a user, e.g., voltage, current, and/or wire feeder parameter values. In the embodiments depicted now such user interface is shown. In general, connector and sensor unit <NUM> may perform no processing using a processor, or may perform processing using a processor such as processor <NUM>.

Analog-to-digital converting, bundling and packetizing may also be performed partly or fully in communications unit <NUM>, which preferably has its own processor and memory (not shown).

In one possible embodiment, connector and sensor unit <NUM> and communications unit <NUM> are integrated into a single physical unit. However, separation of the connector and sensor unit <NUM> and communications unit <NUM> from each other, i.e., separate and apart from each other as is depicted herein, may be more desirable in order to avoid radio frequency (RF) interference to the communications unit <NUM> caused by the possibly noisy high voltage and current passing through the connector and sensor unit <NUM>, and also in order to enable the communications unit <NUM> to be positioned as high as possible to improve wireless connectivity.

In still another embodiment, gas usage rate, or gas volume data can also be provided to communications unit <NUM> via connector and sensor unit <NUM>, or directly through other (wireless or wired) means. Such data can also be supplied to cloud server <NUM>.

In an embodiment, processor <NUM> (or a processor in communications unit <NUM>) may be a simple programmable logic device (SPLD), complex programmable logic device (CPLD), field programmable gate array (FPGA), microprocessor, or application specific integrated circuit (ASIC) that is configured to execute the logic instructions stored in memory <NUM>.

Memory <NUM>(or a memory in communications unit <NUM>) may be implemented as non-transitory computer readable media such as random access memory (RAM) or other dynamic storage device (e.g., dynamic RAM (DRAM), static RAM (SRAM), and synchronous DRAM (SD RAM)), read only memory (ROM) or other static storage device (e.g., programmable ROM (PROM), erasable PROM (EPROM), and electrically erasable PROM (EEPROM)).

As further shown in <FIG>, supply power circuitry <NUM> may be fed power via two inductors L1 and L2, respectively connected to the plus and minus welding voltages cables <NUM> (<NUM>), <NUM>. The inductors L1, L2 are configured such that sufficient power may be drawn from the welding cables, while not significantly degrading the available power for welding functions, in particular any high frequency arc ignition voltages that may be present on the plus and minus welding voltage cables. Although two inductors are shown, it is possible that only one inductor or no inductors could be employed. In a single inductor case, the inductor may be disposed between the plus voltage welding cable <NUM> (<NUM>) and the supply power circuitry <NUM>, or the minus voltage welding cable <NUM> and the supply power circuitry <NUM>. Two inductors may be used to ensure that even if the welding cables are attached to connector and sensor unit <NUM> in a reverse way, HF ignition voltage waveforms are still steered toward torch <NUM>, and not supply power circuitry <NUM>.

Several parameters are taken into account to determine a value for inductors L1 and L2, including:.

The parameters may be dependent on any one or more of the following interactions:.

The following is an example in which supply power conditioning circuitry <NUM> is expected to supply <NUM> W of power to communications unit <NUM>.

Assume the input voltage is <NUM>-<NUM> V between the welding cables, and the required output voltage from the supply power conditioning circuitry <NUM> is <NUM> V.

A <NUM>% reduction of HF voltage is acceptable.

For this example, the interaction among the parameters is as follows:.

Those skilled in the art will appreciate that other values of inductance may be used, resulting in different amounts of damping of the high frequency, high voltage waveforms. A range of permissible damping may be on the order of <NUM>% up to <NUM>%.

In a working prototype, inductor material was selected to avoid reduction of permeability due to DC current through the winding. However, less expensive material may also be selected to achieve the desired function. For the specific material selected, <NUM> turns were used for the winding.

With a core having a height of <NUM>, an outer diameter of <NUM> and an inner diameter of <NUM>, the length of <NUM> copper wire used was <NUM>.

<FIG> depicts a flow chart of plurality of operations that may be performed by the connector and sensor unit <NUM> in accordance with an example embodiment. At <NUM> the connector and sensor unit is configured to source power from, respectively, a first (e.g., a plus voltage) welding cable of a welding apparatus and/or a second (e.g., a minus voltage) welding cable of the welding apparatus. At <NUM>, the connector and sensor unit is configured to generate a predetermined DC voltage from voltage available on the first welding cable of the welding apparatus and the second welding cable of the welding apparatus. At <NUM>, the connector and sensor unit is configured to sense a current being supplied by the first welding cable and/or the second welding cable, and generate a corresponding current sense signal. At <NUM>, the connector and sensor unit is configured to sense a voltage between the first welding cable and the second welding cable, and generate a corresponding voltage sense signal. At <NUM>, the connector and sensor unit is configured to supply the predetermined DC voltage to a communications unit to power the communications unit, or power storage device therein. And at <NUM>, the connector and sensor unit is configured to send at least the current sense signal and the voltage sense signal to the communications unit which is configured to send data indicative of the current sense signal and the voltage sense signal to a remote server.

Those skilled in the art will appreciate that the operations described in connection with <FIG> could also be performed in a different order or selectively simultaneously.

Claim 1:
A connector and sensor unit (<NUM>) for a welding apparatus, comprising
a first port configured to be connected to a first welding cable (<NUM>) of the welding apparatus;
a second port configured to be connected to a second welding cable (<NUM>) of the welding apparatus;
current sensor circuitry (<NUM>) configured to sense a current being supplied to the first port and the second port, and to output a corresponding current sense signal (<NUM>);
voltage sensing circuitry (<NUM>) configured to sense a voltage between the first port and the second port, and to output a corresponding voltage sense signal (<NUM>) ; and
supply power circuitry (<NUM>) configured to generate a predetermined voltage for at least the current sensor circuitry,
wherein the supply power circuitry (<NUM>) is configured to receive power via the first port and second port when the first welding cable (<NUM>) and the second welding cable (<NUM>) are connected thereto, characterised in that the connector and sensor unit (<NUM>) further comprises first and second inductors (L1, L2), and the power is received via, respectively, the first inductor and the second inductor (L1,L2), and the first inductor and the second inductor are configured to dampen a high frequency arc ignition voltage, generated by the welding apparatus and carried by the first welding cable and the second welding cable, by no more than <NUM>%.