[0001] This international application claims priority to U.S. Patent Application Serial No. 15/928,272, filed March 22, 2018, entitled“INDUCTION HEATING EXTENSION CABLES INCLUDING CONTROL CONDUCTORS.” The entirety of U.S. Patent Application Serial No. 15/928,272 is incorporated herein by reference.

BACKGROUND

[0002] 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

[0003] 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

[0004] FIG. 1A is a block diagram of an example induction heating system including a cable assembly constructed in accordance with aspects of this disclosure.

[0005] FIG. 1B is a block diagram of another example induction heating system, in accordance with aspects of this disclosure.

[0006] FIG. 2 is an example implementation of the cable assembly of FIGS. 1A and/or 1B.

[0007] The figures are not necessarily to scale. Where appropriate, similar or identical reference numbers are used to refer to similar or identical components. DET AILED DESCRIPTION

[0008] 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.

[0009] 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.

[0010] 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.

[0011] 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.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] FIG. 1A 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.

[0017] The cable assembly 102 includes an outer protective layer 110, multiple conductors 112a, 112b in a Litz configuration, and a second set of two or more conductors 114. The Litz conductors H2a, H2b provide current to the heating cable 107. When the heating cable l07are 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 l07induce Eddy currents into the workpiece 106 to inductively heat the workpiece 106. In some examples, each of the example Litz conductors H2a, H2b 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 1 l2a, 1 l2b, 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 H2a 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 H2b have a combined total cross-sectional area of at least 8.37 square millimeters). In still other examples, the combination of the Litz conductors 1 l2a, 1 l2b may have effective gauge equivalent to AWG 8 (e.g., each of the Litz conductors H2a, H2b may have a gauge equivalent less than AWG 8).

[0018] 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 1 l2a, 112b 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 112a, 112b 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. [0019] The example cable assembly 102 of FIG. 1A further includes a power supply coupler 116 and a heating cable coupler 118. The power supply coupler 116 couples the conductors 1 l2a, 1 l2b to power terminals l20a, l20b (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 l20a, l20b 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 l20a, l20b and the communications terminal 122 are integrated into the same connector, to which the power supply coupler 116 may connect.

[0020] The heating cable coupler 118 couples the conductors 112a, 112b 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.

[0021] 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 H2a, H2b that carry the induction heating power, and the conductors 114 and the conductors 112a, 112b are contained within an outer protective layer 110 of the cable assembly 102. In the example of FIG. 1A, 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] FIG. 1B is a block diagram of another example induction heating system 150. The induction heating system 150 of FIG. 1B is similar to the induction heating system 100 of FIG. 1A, 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 1 l2a, 1 l2b in the Litz configuration, the second set of two or more conductors 114, the power supply coupler 116, the power terminals l20a, l20b, and the communications terminal 122.

[0029] 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. 1B passes the heating power from the conductors H2a, H2b through to the heating cable 107. In some examples, the induction heating monitor 108 may include connectors and/or terminations for the conductors 1 l2a, 1 l2b and for the heating cable 107, and include passthrough conductors to connect the conductors 112a, 112b and the heating cable 107.

[0030] The example induction heating monitor 108 of FIG. 1B 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.

[0031] 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. [0032] FIG. 2 is an example implementation of the cable assembly 102 of FIGS. 1A and/or 1B. 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.

[0033] 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.

[0034] 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.

[0035] 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.