Patent Publication Number: US-2023147332-A1

Title: Induction heating extension cables including control conductors

Description:
RELATED APPLICATIONS 
     This patent is a continuation-in-part of U.S. patent application Ser. No. 15/869,220, filed Jan. 12, 2018, entitled “INDUCTION HEATING EXTENSION CABLES INCLUDING CONTROL CONDUCTORS,” which claims priority to U.S. Provisional Patent Application Ser. No. 62/447,161, filed Jan. 17, 2017, entitled “INDUCTION HEATING EXTENSION CABLES INCLUDING CONTROL CONDUCTORS.” The entireties of U.S. Provisional Patent Application Ser. No. 62/447,161 is incorporated herein by reference. 
    
    
     BACKGROUND 
     Induction heating of workpieces to be welded, such as pipe, often involves arranging a fixture and/or one or more conductive cables in proximity to the workpiece. The power supply that provides induction heating power may be located a substantial distance from the workpiece and/or the fixture, such that measuring heating parameters directly at the power supply is not feasible. 
     SUMMARY 
     Induction heating extension cables including control conductors are disclosed, substantially as illustrated by and described in connection with at least one of the figures, as set forth more completely in the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1 A  is a block diagram of an example induction heating system including a cable assembly constructed in accordance with aspects of this disclosure. 
         FIG.  1 B  is a block diagram of another example induction heating system, in accordance with aspects of this disclosure. 
         FIG.  2    is an example implementation of the cable assembly of  FIGS.  1 A and/or  1 B . 
     
    
    
     The figures are not necessarily to scale. Where appropriate, similar or identical reference numbers are used to refer to similar or identical components. 
     DETAILED DESCRIPTION 
     Induction heating extension cables deliver induction heating current between an induction heating power supply (e.g., a power supply producing and/or converting induction heating currents) and an induction heating cable (e.g., a cable that is positioned proximate a workpiece such that the induction heating currents induce eddy currents within the workpiece). Induction heating extension cables may have the induction heating current-carrying conductors tightly coupled to reduce (e.g., minimize or eliminate) leakage and improve efficiency. 
     In contrast with conventional cables, disclosed example extension cables include an additional control cable that transfers data and/or power and that is contained within the outer protective layer of the extension cable (e.g., is not exterior to the extension cable). Disclosed example extension cables couple an induction heating power supply to a remote device, which may be located near the workpiece, to exchange data with the remote device and/or provide power to the remote device. Additionally, disclosed examples may omit electrical isolation measures that may be required when the data is electrically coupled to high-power heating conductors, while being protected by the relatively tough outer jacket or protective layer of the extension cable from physical damage that may occur in a welding-type environment. 
     Disclosed example cable assemblies include: a first plurality of conductors in a Litz cable arrangement, an outer protective layer configured to protect the first plurality of conductors from physical damage, and a second plurality of conductors that are electrically isolated from the first plurality of conductors and are protected by the outer protective layer from physical damage. 
     In some example cable assemblies, the second plurality of conductors include a twisted pair of wires. In some example cable assemblies, the second plurality of conductors include coaxial conductors. Some example cable assemblies further include a coupler to couple the first plurality of conductors to an induction heating cable and to couple the second plurality of conductors to an induction heating accessory. In some such examples, the second plurality of conductors conduct at least one of power or data between the induction heating accessory and an induction heating power supply. 
     In some examples, the first plurality of conductors are configured to conduct induction heating current. In some examples, the first plurality of conductors have a total cross-sectional area of at least 8.37 square millimeters, exclusive of electrical insulation. Some example cable assemblies further include a coupler to couple the first plurality of conductors to an induction heating power supply and to couple the second plurality of conductors to the induction heating power supply. In some such examples, the coupler couples the first plurality of conductors to power connectors of the induction heating power supply. In some examples, the coupler couples the second plurality of conductors to a communication connector of the induction heating power supply. 
     Disclosed example induction heating systems include an induction heating power supply, a monitoring device remote from the induction heating power supply, and a cable assembly. The cable assembly includes a first plurality of conductors in a Litz cable arrangement, an outer protective layer configured to protect the first plurality of conductors from physical damage, and a second plurality of conductors that are electrically isolated from the first plurality of conductors and are protected by the outer protective layer from physical damage. 
     In some examples, the second plurality of conductors comprise a twisted pair of wires. In some examples, the second plurality of conductors comprise coaxial conductors. Some example induction heating systems further include a coupler to couple the first plurality of conductors to an induction heating cable and to couple the second plurality of conductors to the monitoring device. In some such examples, the second plurality of conductors conduct at least one of power or data between the monitoring device and the induction heating power supply. 
     In some example induction heating systems, the first plurality of conductors conduct induction heating current. In some examples, the first plurality of conductors have a total cross-sectional area of at least 8.37 square millimeters, exclusive of electrical insulation. Some example induction heating systems further include a coupler to couple the first plurality of conductors to the induction heating power supply and to couple the second plurality of conductors to the induction heating power supply. In some such examples, the coupler couples the first plurality of conductors to power connectors of the induction heating power supply. In some examples, the coupler couples the second plurality of conductors to a communication connector of the induction heating power supply. 
       FIG.  1 A  is a block diagram of an example induction heating system  100  including a cable assembly  102 . The heating system  100  includes an induction heating power supply  104  that provides heating power to a workpiece  106  via the cable assembly  102  and an induction heating cable  107 . The system  100  further includes a induction heating monitor  108 . The induction heating monitor  108  may be a monitoring device for monitoring the workpiece  106  and/or may be any other type of induction heating accessory. 
     The cable assembly  102  includes an outer protective layer  110 , multiple conductors  112   a ,  112   b  in a Litz configuration, and a second set of two or more conductors  114 . The Litz conductors  112   a ,  112   b  provide current to the heating cable  107 . When the heating cable  107  are arranged proximate the workpiece  106  (e.g., wrapped around the workpiece  106 , attached to a fixture configured to direct the current to the workpiece  106 ), the power supply  104  and the heating cable  107  induce Eddy currents into the workpiece  106  to inductively heat the workpiece  106 . In some examples, each of the example Litz conductors  112   a ,  112   b  may have effective gauge equivalent to American Wire Gauge (AWG) 8 (e.g., a total cross-sectional area of at least 8.37 square millimeters, exclusive of the electrical insulation of the Litz conductors) or larger. In examples in which multiple Litz conductors are used to implement each of the Litz conductors  112   a ,  112   b , the combination of Litz conductors used to implement each of the Litz conductors has an effective gauge equivalent to AWG  8  or larger (e.g., multiple conductors implementing the Litz conductor  112   a  have a combined total cross-sectional area of at least 8.37 square millimeters, exclusive of the electrical insulation of the Litz conductors, and multiple conductors implementing the Litz conductor  112   b  have a combined total cross-sectional area of at least 8.37 square millimeters). In still other examples, the combination of the Litz conductors  112   a ,  112   b  may have effective gauge equivalent to AWG  8  (e.g., each of the Litz conductors  112   a ,  112   b  may have a gauge equivalent less than AWG  8 ). 
     The second conductors  114  are contained within the outer protective layer  110  (e.g., an outer jacket) of the cable assembly  102 , but is electrically isolated from the Litz conductors  112   a ,  112   b  so as to be isolated from the relatively high currents and/or voltages. The example outer protective layer  110  may be constructed using, for example, a thermoplastic polyester elastomer (e.g., Hytrel®), polyurethane and/or any other material and/or combination of materials that provides mechanical and electrical protection to the Litz conductors  112   a ,  112   b  and the second conductors  114 . The second conductors  114  may deliver power to the induction heating monitor  108  and/or exchange data signals between the power supply  104  and the induction heating monitor  108 . Example implementations of the second conductors  114  include one or more twisted pairs of conductors or one or more coaxial cables. Other implementations may also be used. 
     The example cable assembly  102  of  FIG.  1 A  further includes a power supply coupler  116  and a heating cable coupler  118 . The power supply coupler  116  couples the conductors  112   a ,  112   b  to power terminals  120   a ,  120   b  (e.g., positive and negative terminals) of the induction heating power supply  104  and/or couples the second conductors  114  to a communications terminal  122  of the induction heating power supply  104 . The power terminals  120   a ,  120   b  may be studs that transmit the heating power for heating the workpiece  106  via the induction heating cable  107 . The example induction heating power supply  104  may exchange data and/or provide power to the induction heating monitor  108  via the communications terminal  122 . In some examples, the power terminals  120   a ,  120   b  and the communications terminal  122  are integrated into the same connector, to which the power supply coupler  116  may connect. 
     The heating cable coupler  118  couples the conductors  112   a ,  112   b  to the induction heating cable  107 . The heating cable coupler  118  also couples the conductors  114  to the induction heating monitor  108  via external conductors  124 . The external conductors  124  may be of the same type as the conductors  114  within the cable assembly  102 . For example, if the conductors  114  include twisted pairs of wires, the external conductors  124  may also be twisted pairs of wires. The external conductors  124  may be replaceable so that the appropriate length of external conductors  124  can be used to position the induction heating monitor  108  in a desired location. 
     The example induction heating monitor  108  communicates with the induction heating power supply  104  via the conductors  114  of the cable assembly  102 . As mentioned above, the conductors  114  are electrically isolated from the conductors  112   a ,  112   b  that carry the induction heating power, and the conductors  114  and the conductors  112   a ,  112   b  are contained within an outer protective layer  110  of the cable assembly  102 . In the example of  FIG.  1 A , the induction heating monitor  108  communicates and/or receives power via the conductors  114  within an extension cable. However, the conductors  114  may also be included at least partially within the heating cable  107 . 
     The induction heating monitor  108  includes a communications circuit  126 , a control circuit  128 , a data collection circuit  130 , a power circuit  132 , an energy storage device  134 , a user interface  136 , and sensor interface(s)  138 . The example communications circuit  126  includes a transmitter circuit  140  and a receiver circuit  142 . 
     The example transmitter circuit  140  transmits the induction heating data to the induction heating power supply  104  via the conductors  114  via the external conductors  124  and the heating cable coupler  118 . The example receiver circuit  142  may receive data from the induction heating power supply  104 . The induction heating power supply  104  may include similar communication circuitry, including transmitter circuitry and/or receiver circuitry, to receive induction heating data and/or transmit configuration data to the induction heating monitor  108 . In some examples, the induction heating power supply  104  modifies an induction heating output (e.g., induction heating power, etc.) based on the induction heating data received from the induction heating monitor  108  via the conductors  114 . 
     The transmitter circuit  140  frames induction heating data for transmission via the conductors  114 . The induction heating data may be generated from sensor data collected by one or more sensors  144  via the sensor interface(s)  138  and/or the data collection circuit  130 . The data collection circuit  130  may include sensor digitizer(s)  146  to digitize data received from the sensor(s)  144 . The induction heating data may be converted to digital data via the sensor digitizer  146  and/or input by a user or operator via the user interface  136 . 
     The example sensor(s)  144  may include a temperature sensor (e.g., a thermocouple, a thermistor, a resistive temperature device, an infrared sensor, a semiconductor-based temperature sensor, etc.), a coolant pressure sensor, or a coolant flow sensor, and/or a location sensor. Example induction heating data includes one or more of an ambient temperature at the workpiece  106  being heated with the induction heating cable  107 , a temperature of the induction heating cable  107 , a temperature of a blanket in contact with the induction heating cable  107 , a temperature of the workpiece  106 , a measurement of current flowing through the induction heating cable  107 , a voltage measurement of a voltage at the induction heating cable  107  (e.g., a voltage across the portion of the induction heating cable  107  inductively coupled to the workpiece  106 ), an error signal, a temperature of coolant flowing through the induction heating cable  107 , a coolant pressure, a coolant flow rate, a workpiece identifier, an induction heating cable identifier, an operator identifier, date information, time information, geographic information, a cable fixture identifier, and/or any type of operator or user input entered at the induction heating monitor  108 . 
     The power circuit  132  extracts power from the conductors  114 ,  124 , which may be multiplexed with data signals. The power circuit  132  provides power to the data collection circuit  130 , the sensors  144  (e.g., via the sensor interface(s)  138 ), the control circuit  128 , the user interface  136 , and/or the communications circuit  126 . Additionally or alternatively, the power circuit may charge the energy storage device  134 . The example energy storage device  134  provides power to the data collection circuit  130 , the sensors  144  (e.g., via the sensor interface(s)  138 ), the control circuit  128 , the user interface  136 , and/or the communications circuit  126  when the power circuit  132  is not capable of powering the components. The example energy storage device  134  may include one or more batteries, one or more capacitors, and/or any other type of energy storage device. 
     The example user interface  136  may include any type(s) of user interface devices, such as selection buttons, switches, dials, number pads, touchscreens, and/or any other type of user interface device. 
       FIG.  1 B  is a block diagram of another example induction heating system  150 . The induction heating system  150  of  FIG.  1 B  is similar to the induction heating system  100  of  FIG.  1 A , and includes the cable assembly  102 , the induction heating power supply  104 , the workpiece  106 , the induction heating cable  107 , the induction heating monitor  108 , the outer protective layer  110 , the conductors  112   a ,  112   b  in the Litz configuration, the second set of two or more conductors  114 , the power supply coupler  116 , the power terminals  120   a ,  120   b , and the communications terminal  122 . 
     In contrast with the example system  100  of  FIG.  1 A , the example system  150  couples the cable assembly  102  to the induction heating monitor  108  instead of a heating cable coupler  118 . The example induction heating monitor  108  receives the power and/or data via the second conductors  114  (e.g., by terminating the second conductors  114 ). The induction heating monitor  108  of  FIG.  1 B  passes the heating power from the conductors  112   a ,  112   b  through to the heating cable  107 . In some examples, the induction heating monitor  108  may include connectors and/or terminations for the conductors  112   a ,  112   b  and for the heating cable  107 , and include passthrough conductors to connect the conductors  112   a ,  112   b  and the heating cable  107 . 
     The example induction heating monitor  108  of  FIG.  1 B  includes the communications circuit  126 , the control circuit  128 , the data collection circuit  130 , the power circuit  132 , the energy storage device  134 , the user interface  136 , and the sensor interface(s)  138 . The induction heating monitor  108  collects induction heating data from one or more sensor(s)  144 . 
     While example couplers  116 ,  118  are disclosed, the example cable assembly  102  may be coupled to the induction heating power supply  104 , the heating cable  107 , and/or the induction heating monitor  108  using any combination and/or types of couplers and/or hard wiring. 
       FIG.  2    is an example implementation of the cable assembly  102  of  FIGS.  1 A and/or  1 B . The example cable assembly  102  includes four Litz wire bundles  202 , two conductors  204  arranged in a twisted pair configuration, an outer jacket  206 , and an internal wrap  208 . Each of the Litz wire bundles  202  and the conductors  204  include an additional jacket  210 , which may be constructed of a thermoplastic elastomer (TPE). The example outer jacket  206  is constructed of a thermoplastic polyester elastomer (e.g., Hytrel®), polyurethane and/or any other material and/or combination of materials that provides mechanical and electrical protection to the Litz wire bundles  202  and the conductors  204 . The internal wrap  208  may be constructed using polytetrafluoroethylene (PTFE) tape. 
     As shown in  FIG.  2   , the outer jacket  206  provides an outer protective layer that protects the Litz wire bundles  202  and the twisted pair conductors  204  from physical damage. 
     As utilized herein, “and/or” means any one or more of the items in the list joined by “and/or”. As an example, “x and/or y” means any element of the three-element set {(x), (y), (x,y)}. In other words, “x and/or y” means “one or both of x and y”. As another example, “x, y, and/or z” means any element of the seven-element set {(x), (y), (z), (x,y), (x,z), (y,z), (x,y,z)}. In other words, “x, y and/or z” means “one or more of x, y and z”. As utilized herein, the term “exemplary” means serving as a non-limiting example, instance, or illustration. As utilized herein, the terms “e.g.,” and “for example” set off lists of one or more non-limiting examples, instances, or illustrations. 
     While the present method and/or system has been described with reference to certain implementations, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present method and/or system. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. For example, blocks and/or components of disclosed examples may be combined, divided, re-arranged, and/or otherwise modified. Therefore, it is intended that the present method and/or system not be limited to the particular implementations disclosed, but that the present method and/or system will include all implementations falling within the scope of the appended claims, both literally and under the doctrine of equivalents.