Patent Publication Number: US-2019168333-A1

Title: Sensor-based power controls for a welding system

Description:
BACKGROUND 
     The invention relates generally to welding systems, and, more particularly, to sensing systems for controlling power supplies or accessories of a welding system using motion sensors. 
     Welding is a process that has become ubiquitous in various industries for a variety of types of applications. For example, welding is often performed in applications such as shipbuilding, aircraft repair, construction, and so forth. The welding systems often include power sources that may generate power for consumption during the welding process. However, these power sources may generate power even when unneeded due to inactivity of the welding torch. Furthermore, if the power sources are inactive or producing reduced power until a demand event (e.g., a trigger is pressed), there may be a period of time during which power is desired but unavailable. 
     BRIEF DESCRIPTION 
     In a first embodiment, a welding system includes a power source and a torch motion sensing system associated with a welding torch and configured to sense welding torch orientations or movements. The welding system also includes a processing system communicatively coupled to the torch motion sensing system. The processing system is configured to determine movement of the welding torch prior to a welding demand from the welding torch, and to send an indication to the power source to provide power at a generation level sufficient to operate the welding torch. 
     In another embodiment, a method includes sensing an initial orientation of a welding torch, via a torch motion sensing system and sensing subsequent orientations of the welding torch, via the torch motion sensing system. The method also includes activating a power source associated with the welding torch if the power source is turned off and the subsequent orientations differ from the initial orientation. Furthermore, the method includes activating a higher power state for the power source if the power source is in a low-power state and the subsequent orientations differ from the initial orientation. 
     In a further embodiment, a retro-fit kit configured to couple to a welding torch includes a torch motion sensing system configured to determine orientations or movements of the welding torch. Furthermore, the retro-fit kit includes a processor configured to send instructions to a power supply for the welding torch to provide power in response to movements of the welding torch or changes in orientations of the welding torch. 
    
    
     
       DRAWINGS 
       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: 
         FIG. 1  is a block diagram of an embodiment of a welding system utilizing a power supply and a welding torch with motion sensors; 
         FIG. 2  is a flowchart of an embodiment of a power control process that may be used by the welding system of  FIG. 1 ; 
         FIG. 3  is a flowchart of an embodiment of a power control process that may be used by the welding system of  FIG. 1 ; 
         FIG. 4  is a block diagram of an embodiment of the power supply and welding torch of  FIG. 1 ; 
         FIG. 5  is a flowchart of an embodiment of a gesture control process that may be used to control the welding system of  FIG. 1 ; and 
         FIG. 6  is a perspective view of an embodiment of a welding torch  100  that may be used in the welding system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     As will be described in detail below, provided herein are systems and methods for using motion (e.g., inertial) sensors in a welding torch to determine likelihood of power demand prior to actual demand to reduce delays in power availability and/or waste of generated power. By determining that a welding torch is being moved, the welding system may determine demand is likely imminent and that a higher level power generation state should be initiated even before explicit requests (e.g., pressing a trigger on the torch). The generation of power when the welding torch determines that the demand is likely imminent allows a power source to ramp up power earlier, thereby reducing or eliminating a deficit in power available at the time of initial demand. 
     Turning now to the figures,  FIG. 1  is a block diagram of an embodiment of a welding system  10  in accordance with the present techniques. The welding system  10  is designed to produce a welding arc  12  with a workpiece  14  (e.g., pipe). The welding arc  12  may be generated by any type of welding system or process, and may be oriented in any desired manner. For example, such welding systems may include gas metal arc welding (GMAW) systems, and may utilize various programmed waveforms and settings. The welding system  10  includes a power supply  16  (e.g., engine-driven generator in some embodiments) that will typically be coupled to a power source  18 , such as a power grid, an engine, or a combination thereof (e.g., hybrid power). Other power sources may, of course, be utilized including generators and so forth. In the illustrated embodiment, a wire feeder  20  is coupled to a gas source  22  and the power source  18 , and supplies welding wire  24  to a welding torch  26 . The welding torch  26  is configured to generate the welding arc  12  between the welding torch  26  and the workpiece  14 . The welding wire  24  is fed through the welding torch  26  to the welding arc  12 , melted by the welding arc  12 , and deposited on the workpiece  14 . 
     The wire feeder  20  will typically include wire feeder control circuitry  28 , which regulates the feed of the welding wire  24  from a spool  29  and commands the output of the power supply  16 , among other things. Similarly, the power supply  16  may include power supply control circuitry  30  for controlling certain welding parameters and arc-starting parameters. In certain embodiments, the wire feeder control circuitry  28  or the power supply control circuitry  30  may be include software, hardware, or a combination thereof. For example, in certain embodiments, the wire feeder control circuitry  28  and/or the power supply control circuitry  30  may include a processor and memory configured to store instructions to be executed by the processor. In some embodiments, the wire feeder control circuitry  28  may communicate with the power supply control circuitry  30  through a weld cable  31  that is also used to provide power to the wire feeder  20 . The spool  29  of the wire feeder  20  will contain a length of welding wire  24  that is consumed during the welding operation. The welding wire  24  is advanced by a wire drive assembly  32 , typically through the use of an electric motor under control of the control circuitry  28 . In addition, the workpiece  14  is coupled to the power supply  16  by a clamp  34  connected to a work cable  36  to complete an electrical circuit when the welding arc  12  is established between the welding torch  26  and the workpiece  14 . 
     Placement of the welding torch  26  at a location proximate to the workpiece  14  allows electrical current, which is provided by the power supply  16  and routed to the welding torch  26 , to arc from the welding torch  26  to the workpiece  14 . As described above, this arcing completes an electrical circuit that includes the power supply  16 , the welding torch  26 , the workpiece  14 , and the work cable  36 . Particularly, in operation, electrical current passes from the power supply  16 , to the welding torch  26 , to the workpiece  14 , which is typically connected back to the power supply  16  via the work cable  36 . The arc generates a relatively large amount of heat that causes part of the workpiece  14  and the filler metal of the welding wire  24  to transition to a molten state that fuses the materials, forming the weld. 
     In certain embodiments, to shield the weld area from being oxidized or contaminated during welding, to enhance arc performance, and to improve the resulting weld, the welding system  10  may also feed an inert shielding gas to the welding torch  26  from the gas source  22 . It is worth noting, however, that a variety of shielding materials for protecting the weld location may be employed in addition to, or in place of, the inert shielding gas, including active gases and particulate solids. Moreover, in other welding processes, such gases may not be used, while the techniques disclosed herein are equally applicable. 
     Although  FIG. 1  illustrates a GMAW system, the presently disclosed techniques may be similarly applied across other types of welding systems, including gas tungsten arc welding (GTAW) systems and shielded metal arc welding (SMAW) systems, among others. Accordingly, embodiments of the sensor-based power supply controls may be utilized with welding systems that include the wire feeder  20  and gas source  22  or with systems that do not include a wire feeder  20  and/or a gas source  22  (e.g., embodiments where the welding torch  26  is directly coupled to the power supply  16 ), depending on implementation-specific considerations. 
     Presently disclosed embodiments are directed to sensor-based control of the power supply  16 . In some embodiments, the wire feeder control circuitry  28  and/or the power supply control circuitry  30  may control the power supply  16  based on inertial data derived using at least an accelerometer  38 , gyroscope sensor  40 , and/or magnetometer  41  (collectively referred to as the sensors) located in, on, or associated with the welding torch  26 . For example, in some embodiments, the sensors may be located in a retro-fit kit that may be mounted to the welding torch  26 . Moreover, in some embodiments, the circuitry  30  may individually control the welding power supplied by the power supply  16  based at least in part on the sensor feedback. In certain embodiments, the circuitry  28  may individually adjust wire feed speed based at least in part on the sensor feedback. In other embodiments, and either of circuitries ( 28  or  30 ) may perform their control and send a control signal to the other so that the other can perform their control in yet other embodiments. 
     In certain embodiments, the accelerometer  38  may include a single triaxial accelerometer capable of measuring dynamic motion, such as weld weaving. In other embodiments, the accelerometer  38  may include one or more orientation sensors (e.g., accelerometers) to determine a change of welding torch  26  orientation in one or more dimensions. For example, a two-dimensional position may be calculated with respect to a plane parallel to a direction of gravity based on two accelerometers. Using the accelerometer  38 , the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may determine that the welding torch  26  is in an active state (e.g., upright position) or an inactive state. For example, the welding torch  26  may be deemed inactive when remaining substantially motionless for a period of time in a position indicating idleness, such as lying on its side, upside down, or lying with the welding torch  26  facing downward. 
     In some embodiments, the gyroscope sensor  40  may include one or more gyroscope sensors, such as a single triaxial gyroscope sensor. The power supply control circuitry  30  and/or the wire feeder control circuitry  28  may use the gyroscope sensor  40  to supplement data from the accelerometer  38  to measure low value movements, such as oscillatory motions used in certain welding processes (e.g., TIG). 
     In certain embodiments, the magnetometer  41  may include one or more gyroscope sensors, such as a single triaxial magnetometer. The power supply control circuitry  30  and/or the wire feeder control circuitry  28  may use the magnetometer  41  to determine changes in magnetic fields such as movement of the welding torch  26  or other objects in the weld area. 
     Using data from one or more of the sensors, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may control the power supply  16  to ensure that sufficient power is produced when an operator begins to use the welding torch  26 . In certain embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may control the power supply  16  by implementing a power control process  50 , as illustrated in  FIG. 2 . In some embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may implement the process  50  via instructions stored in a non-transitory, computer-readable medium (e.g., memory) and executed by a processor. The power supply control circuitry  30  and/or the wire feeder control circuitry  28  receive data indicative of activity (block  52 ). In some embodiments, the data indicative of activity may be received from the welding torch  26  as data indicating that the torch  26  has moved or that some other object (e.g., via magnetometer  41 ) has moved within the weld area. As will be discussed below, the data may be transmitted to the power supply control circuitry  30  and/or the wire feeder control circuitry  28  via a transmitter located within the torch  26 . 
     Upon receipt of these indicia of activity, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  determines that the torch  26  is likely to be used (e.g., that a depression of a trigger of the torch  26 , to initiate a welding arc, may be imminent). Accordingly, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  determine whether power should be increased by determining whether the power source is active and producing sufficient power (block  54 ). For example, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  determines whether an engine is producing sufficient energy or whether AC line power is sufficient for welding. Since the power supply  16  may be beyond vision or hearing of the operator, in some embodiments, if the power supply  16  is active and producing desired energy, the welding system  10  may indicate that sufficient power is available (block  56 ). As discussed below, available power may be indicated via haptic, visual, or audio feedback through the welding torch  26 , a welding helmet, or external feedback device to an operator indicating that the welding system  10  is ready to provide a desired level of power. However, if the power supply  16  is not active or not ready to provide a desired power level (e.g., the power supply  16  is idling), the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may cause the power supply  16  to turn on or increase power consumption (block  58 ) from input line power, or power production from engine. Once sufficient power consumption is achieved, available power may be indicated to the operator via haptic, visual, or audio feedback. 
     Moreover, in some situations, it may be desirable to reduce power during periods of inactivity. For example, if the power supply  16  includes an engine, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may enable the engine to idle or shutoff when receiving indicia of inactivity, thereby reducing power production based on a sensed lack of demand. One typical form of idle state is disconnecting the input power to the main power converter for output but allows control power connected for communications to the motion sensors and reconnect the main power. One typical power consumption of the main power converter is the magnetizing current of the main transformer. By eliminating power consumption of the main transformer, less power is wasted while the welding torch  26  is inactive. Furthermore, when the power supply  16  includes an engine, the engine can be completely shut off when the welding or gouging tool is not in use. The power supply controls can be powered by battery to communicate with the motion sensors and start the engine as the operator picks up the torch ready for welding. An alternative is to run the engine at low speed for controls only but not sufficient to provide welding power but increase to high speed when the torch is picked up or moved by operator after periods of no movement. Often for stick welding, it needs an initial high power for the first few hundreds of milliseconds for arc ignition so the motion sensor can trigger the engine to go to high speed for arc start, then ramp down to lower speed for the remainder of the weld. Moreover, increased energy consumption using an engine may involve increased fuel consumption, engine wear, and noise production, thereby reducing energy consumption may reduce fuel consumption, engine wear, noise production, and so forth. 
     It is also possible to tag different motion sensors with power levels for specific tools. For example, for arc gouging uses much higher power than arc welding. It is possible to that the movement of gouging tool will trigger a higher engine speed sufficient for gouging, and the movement of the welding tool will trigger a lower engine speed sufficient for welding when the engine is waken from sleeping state (shut off). 
     Accordingly,  FIG. 3  illustrates a power control process  60  that may be implemented by the power supply control circuitry  30  and/or the wire feeder control circuitry  28 . The power supply control circuitry  30  and/or the wire feeder control circuitry  28  may receive an indication of inactivity (block  62 ). For example, if the power supply control circuitry  30  and/or the wire feeder control circuitry  28  determines that the welding torch  26  has remained substantially motionless or in a position indicating idleness, such as laying on its side, upside down, or laying with the welding torch  26  facing downward, for a given period of time. If the power supply  16  is active or producing power (block  64 ), the power supply control circuitry  30  and/or the wire feeder control circuitry  28  determines if a power reduction duration has elapsed (block  66 ). In other words, in some embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may allow some amount of idleness (e.g., less than a minute) without controlling power production. In some embodiments, more than one duration may be used. For example, in some embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may cause an engine to idle after a first threshold (e.g., 5 minutes) of inactivity is surpassed and to turn off when a second threshold (e.g., 10 minutes) is surpassed. 
     Upon determination that the welding torch  26  is inactive for some period and the power supply  16  is producing unused power, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  reduces power production (block  68 ). Otherwise, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  do not adjust power production. As discussed above, in some embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may reduce power in one or more steps. For example, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may reduce a power production level at various intervals of inactivity and shut off power production after another duration of inactivity. 
       FIG. 4  illustrates a block diagram view of an embodiment of a power supply  16  and welding torch  26  that may be used to implement the power control processes  50  and  60  discussed above. The welding torch  26  may include at least one of the magnetometer  41 , the accelerometer  38 , and the gyroscope  40 . In some embodiments having one or more of the sensors, a data fusion unit  70  may receive the measurements from the magnetometer  41 , the accelerometer  38 , and the gyroscope  40  and may fuse the data for transmission via a transmitter  72 . For example, a magnetometer  41  may detect changes in a magnetic field while the accelerometer  38  detects movement. The data fusion unit  70  may fuse the data by using data from both sensors to an accurate model of welding torch movement. In some embodiments, the data fusion unit  70  may fuse data from sensors external to the welding torch  26  (e.g., a light sensor in the weld area) with the internal sensors. In other embodiments, only one of the sensors may be relied upon at a time without fusing the data or having a data fusion unit  70 . In some embodiments, the data from the sensors may be transmitted by the transmitter  72  without first being fused such that the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may receive the data separately and analyze the information. In some embodiments, the data fusion unit  70  may include hardware, software, or some combination thereof (e.g., processor and memory storing instructions). 
     The transmitter  72  used to transmit information from the welding torch  26  to the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may include wired or wireless connections. For example, in the illustrated embodiment, the transmitter  72  transmits sensor data to a receiver  74  of the power supply control circuitry  30  using the weld cable  31  that is used to power the welding torch  26 . In certain embodiments, the wire feeder  20  may also include a transmitter, a receiver, or a transceiver. In some embodiments, the transmitter  72  may transmit sensor data to the receiver  74  using a data line separate from the weld cable  31 . In some embodiments, the transmitter  72  and the receiver  74  may include wireless communication radios configured to transmit and receive data wirelessly. For example, in some embodiments, the transmitter  72  and the receiver  74  may include transceivers configured to communicate via 802.11 (WiFi), 802.15.4, ZigBee®, 802.15.1, Bluetooth, Cellular Machine to Machine (M2M) technologies. 
     In some embodiments, the welding torch  26  includes a torch power storage  76  (e.g., chemical batteries or capacitors) that may be used to provide power for operating the sensors, the data fusion unit  70 , and/or the transmitter  72 . In some embodiments, the sensors, the data fusion unit  70 , and/or the transmitter  72  may be at least partially powered by the power supply  16  when the power supply  16  is producing power. However, in certain embodiments, the welding torch  26  may also include an energy harvester  78  that may be used to replenish the torch power storage  76  during operation of the welding torch  26 . The energy harvester  78  scavenges power (e.g., electricity, heat, magnetic fields, etc.) from the immediate environment to power the sensors. For example, an inductive unit of the energy harvester  78  may extract a small amount of energy from the fluctuating current in the weld cable  31  to charge the torch power storage  76 . 
     In some embodiments, a feedback unit  80  may be used to alert the operator that a level of power is being produced to enable the operator to determine whether sufficient power is available for using the welding torch  26 . In some embodiments, the feedback unit  80  may include one or more LEDs, one or more sound emitting units (e.g., speakers), one or more haptic feedback units, dials, meters, other units suitable for indicating power availability, or some combination thereof. The present embodiment illustrates the feedback unit  80  as part of the welding torch  26 . In some embodiments, the feedback unit  80  may be located within a welding helmet, separate from the operator in the weld area, on the welding torch  26 , or some combination thereof 
     In some embodiments, the sensors may be used to determine more than presence of motion. In some embodiments, the sensors may be used to determine various gestures to a change in weld process. For example,  FIG. 5  illustrates a flow chart of a gesture control process  90  that may be used to control the welding system  10 . The welding system  10  receives a recognized gesture (block  92 ). In some embodiments, various gestures may be preprogrammed the power supply control circuitry  30  and/or the wire feeder control circuitry  28  or later learned using the welding torch  26 . For example, the gestures may include a horizontal swipe (e.g., left or right), a vertical swipe (e.g., up or down), a circular motion (e.g., clockwise or counterclockwise loop), a twist (e.g., clockwise or counterclockwise rotation of the torch  26 ), or other gestures that may be recognized by the sensors. In other words, the raw data generated by the sensors may be analyzed to determine when certain gestures are being performed by the operator using the welding torch  26 . In some embodiments, the gestures may be analyzed by a preprocessor (e.g., the data fusion unit  70 , in certain embodiments) prior to communication to the power supply control circuitry  30  and/or the wire feeder control circuitry  28 . In other words, in such embodiments, raw data may be analyzed by the data fusion unit  70 , and the data fusion unit  70  transmits which gestures are recognized to the power supply control circuitry  30  and/or the wire feeder control circuitry  28 . In other embodiments, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may analyze raw data from the sensors to recognize the gestures. 
     Upon receipt of a recognized gesture, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  changes a corresponding weld process parameter (block  94 ). For example, if a rapid left or right swipe is recognized, the power supply control circuitry  30  and/or the wire feeder control circuitry  28  may decrease or increase a corresponding welding parameter, such as voltage for MIG welding or current for shielded metal arc welding (SMAW) and tungsten inert gas (TIG) welding. Additionally or alternative, the welding parameter may include a current for carbon arc gouging (CAG) process, plasma cutting, or welding process or a current for tools powered off auxiliary output of the power source, such as a grinder or pump. In some embodiments, a recognized gesture may progress the power supply through a number of states. 
     Additionally or alternatively, if a clockwise circular motion or a clockwise twist is recognized, an engine of the power supply  16  may be turned on while corresponding clockwise motions may turn off the power supply engine. Such gestures and associated actions are merely exemplary, and not intended to be limiting. Other gestures and resulting actions may also be used. 
       FIG. 6  illustrates a perspective view of an embodiment of a welding torch  100  that may be used in the welding system  10  of  FIG. 1 . The welding torch  100  includes a handle  102  for a welding operator to hold while performing a weld. At a first end  104 , the handle  102  is coupled to a cable  106  where welding consumables are supplied to the weld. Welding consumables generally travel through the handle  102  and exit at a second end  108  opposite from the first end  104 . The welding torch  100  includes a neck  110  extending out of the end  108 . As such, the neck  110  is coupled between the handle  102  and a nozzle  112 . As should be noted, when the trigger  111  is pressed or actuated, welding wire travels through the cable  106 , the handle  102 , the neck  110 , and the nozzle  112 , so that the welding wire extends out of an end  114  (i.e., torch tip) of the nozzle  112 . 
     As illustrated, the handle  102  is secured to the neck  110  via fasteners  116  and  118 , and to the cable  106  via fasteners  120  and  122 . The nozzle  112  is illustrated with a portion of the nozzle  112  removed to show welding wire  124  extending out of a guide or contact tip  126  (or other guiding device). The guide tip  126  is used to guide the welding wire  124  out of the end  114  of the welding torch  100 . Although one type of welding torch  100  is illustrated, any suitable type of welding torch may include the indicator  128 . For example, a welding torch having the indicator  128  may be configured for shielded metal arc welding (SMAW), gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), and so forth. 
     The welding torch  100  may also include one or more motion sensors  130  (e.g., accelerometer) that may detect motion of or near the welding torch  100 . As previously discussed, by detecting motion via the welding torch  100 , the welding system  10  may receive indications of activity or inactivity to control corresponding power management processes. In other words, by relying on the sensors  130 , the welding system  10  may produce power when desired by increasing power production prior to actual demand (e.g., actuation of trigger  111 ) thereby enabling the welding system  10  to reduce power during inactivity without significant lag between power demand and availability of the power. For example, when the sensors  130  detect motion, the power supply  16  may provide power in anticipation of depression of the trigger  111 . 
     Although the foregoing discussion primarily discusses motion sensing for a welding torch, some embodiments may include motion sensing for other tools or accessories. For example, motion sensing may be used for any welding-type tool or accessory associated with a welding-type process. As used herein, welding-type refers to any process related to welding, such as welding, cutting, or gouging. Furthermore, a welding-type tool or accessory may be any tool or accessory using in such processes. For example, welding-type tools may include torches, electrode holders, machining tools, or other similar tools that may be used in the welding-type processes. Moreover, welding-type accessories may include helmet, jackets, gloves, or other equipment that may be used in the welding-type processes. 
     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.