Method and apparatus for controlling heating based on monitoring feedback from a temperature sensor

Abstract

A method and apparatus for controlling heating based on monitoring feedback from a temperature sensor are disclosed. An example heating apparatus includes: a heater configured to apply thermal energy to an object; and a control circuit system configured to: control the heater based on a target temperature to which the object is to be heated; update a first temperature range and the first reference temperature based on the first measured temperature sample in response to determining that a first measured temperature sample associated with a first temperature sensor is greater than a first reference temperature; and reduce the priority of the first temperature sensor for controlling the application of thermal energy to the object in response to determining that a second measured temperature sample associated with the first temperature sensor is not within the first temperature range.

Description

BACKGROUND

[0001] The present disclosure relates generally to heating, and more specifically to methods and apparatus for controlling heating based on monitoring feedback from temperature sensors. SUMMARY

[0002] Methods and apparatus for controlling heating based on monitoring feedback from temperature sensors are disclosed, substantially as illustrated by and described in connection with at least one of the figures, as complete, explicit and comprehensive as in the claims. BRIEF DESCRIPTION OF DRAWINGS

[0003] FIG. 1A An example heating system configured to control a temperature of an object to be heated based on one or more temperature sensors is shown in accordance with aspects of the present disclosure.

[0004] FIG. 1B An example heating system configured to control a temperature of an object to be heated based on one or more temperature sensors is shown in accordance with aspects of the present disclosure.

[0005] FIG. 2 Example measured temperature values during an example process that can be implemented by a heating system of FIG. 1A and / or FIG. 1B are shown, along with example temperature range(s) and reference temperature(s) associated with one or more temperature sensors during a heating process.

[0006] FIG. 3A to FIG. 3C A flowchart representing example machine-readable instructions that can be executed by an example induction heating power supply of FIG. 1A and / or FIG. 1B to control a temperature of an object to be heated based on one or more temperature sensors is shown.

[0007] The drawings are not to scale. Where appropriate, the same or similar reference designators have been used to designate similar or identical elements of the drawings. DETAILED DESCRIPTION

[0008] Conventional heating systems can include algorithms to detect when a thermocouple has failed or become decoupled from the heating control system such that no signal is received from the thermocouple. However, conventional heating systems are unable to detect when a thermocouple or other temperature sensor has become thermally decoupled from the object to be heated but continues to provide feedback. As a result, conventional heating systems can potentially overheat and damage the object and / or damage the heater.

[0009] The disclosed methods and apparatuses provide a thermostatically controlled heating system that heats a workpiece or object to a target temperature, such as for a specified duration and / or at a specified rate. The disclosed example methods and apparatuses include applying heat energy to the object, adjusting energy delivery based on temperature feedback from a temperature feedback device (e.g., a sensor) thermally coupled or incorporated with the object, and monitoring for thermal decoupling of the temperature feedback device. The disclosed example methods and apparatuses take action to stop or correct the heating process, notify a user, and / or take another action in response to detecting thermal decoupling of the temperature feedback device.

[0010] As used herein, the term "induction heating power" refers to AC power that is capable of inducing a current in a workpiece to heat the workpiece by magnetic induction when flowed through a properly arranged cable.

[0011] As used herein, the terms "first," "second," "third," etc. are used to enumerate instances of similar or identical elements, and do not indicate or imply a particular order unless specifically indicated or otherwise understood.

[0012] As used herein, "circuitry" includes any analog and / or digital components, power and / or control elements, such as microprocessors, digital signal processors (DSPs), software, etc., discrete components and / or integrated components, or portions and / or combinations thereof. As used herein, the terms "control circuitry," "control circuitry system," and / or "controller" can include digital and / or analog circuitry, discrete and / or integrated circuitry, microprocessors, digital signal processors (DSPs), and / or other logic circuitry and / or associated software, hardware, and / or firmware. Control circuitry or control circuitry system can be located on one or more circuit boards that form part or all of a controller and are used to control a heating process, a device such as a power supply, and / or any other type of heating-related system.

[0013] As used herein, the term "memory" includes volatile and non-volatile memory devices and / or other storage devices.

[0014] As used herein, "blanket" refers to an insulating layer that covers an induction heating cable and protects the cable. As used herein, the term "identification" can include a serial number, model number, or any other identification value, and can be represented as a quick read (QR) code, a bar code, a human-readable number, a radio frequency identification (RFID) tag, and / or any other machine-readable indicia.

[0015] Although the following disclosed examples are discussed with reference to an inductive heating system, the examples can be modified to use other types of heating. Moreover, the term "heating" includes both heating to raise the temperature of an object and applying heat energy to reduce the rate of convective and / or radiative cooling occurring in the object.

[0016] A disclosed example heating apparatus includes a heater configured to apply heat energy to an object, and control circuitry. The control circuitry is configured to: control the heater based on a target temperature to which the object is to be heated; update a first temperature range and a first reference temperature based on a first measured temperature sample associated with the first temperature sensor in response to determining that the first measured temperature sample is greater than the first reference temperature; and reduce a priority of the first temperature sensor to control application of heat energy to the object in response to determining that a second measured temperature sample associated with the first temperature sensor is not within the first temperature range.

[0017] In some example heating apparatuses, the control circuitry is configured to repeatedly update the first temperature range in response to additional measured temperature samples at times of respective measured temperature samples being greater than the first reference temperature. In some examples, the control circuitry is configured to: compare the additional measured temperature samples to the first temperature range, and reduce the priority of the first temperature sensor to control application of heat energy to the object in response to any of the additional measured temperature samples being outside of the first temperature range according to the comparison.

[0018] In some examples, the control circuitry is configured to not update the first temperature range in response to determining that the first measured temperature sample is not greater than the first reference temperature. In some example heating apparatuses, the heater includes power conversion circuitry configured to convert input power to inductive heating power or resistive heating power. Some example heating apparatuses further include sensor monitoring circuitry configured to receive the first measured temperature sample and the second measured temperature sample, wherein the first temperature sensor includes at least one of a thermocouple, an infrared temperature sensor, or a resistance temperature detector.

[0019] In some examples, the control circuitry is configured to update the first temperature range by setting at least one of a temperature upper limit or a temperature lower limit based on the first measured temperature sample. In some examples, the control circuitry is configured to: reset and initialize a timeout counter in response to beginning to apply heat energy to the object; reset the timeout counter based on the first measured temperature sample in response to determining that the first measured temperature sample associated with the first temperature sensor has increased at least a threshold amount above the reference temperature; and reduce the priority of the first temperature sensor to control application of heat energy to the object in response to the timeout counter reaching a threshold count.

[0020] In some examples, the control circuitry is configured to determine the threshold count based on at least one of an identity of the object, a size of the object, or a material of the object. In some examples, the control circuitry is configured to increment a timeout counter in response to receiving a measured temperature sample. In some example heating devices, the timeout counter is configured to increment based on a clock. In some examples, the control circuitry is configured to demote the first temperature sensor by maintaining a temperature of the object or by stopping application of heat energy to the object by controlling application of the heat energy.

[0021] In some examples, the control circuitry is configured to: in response to determining that a third measured temperature sample associated with the second temperature sensor is greater than the second reference temperature, update the second temperature range and the second reference temperature based on the third measured temperature sample; determine whether control of the heater is based on samples associated with the second temperature sensor; when control of the heater is based on samples associated with the second temperature sensor, in response to determining that the third measured temperature sample associated with the second temperature sensor is not within the second temperature range, demote the second temperature sensor from controlling application of heat energy to the object.

[0022] In some examples, the control circuitry is configured to: when control of the heater is based on samples associated with the first temperature sensor, in response to determining that the third measured temperature sample associated with the second temperature sensor is not within the second temperature range, continue control of the heater based on the first temperature sensor. In some example heating devices, the control circuitry is configured to demote the first temperature sensor from controlling application of heat energy to the object to a priority lower than a priority of the second temperature sensor for controlling application of heat energy to the object.

[0023] Some disclosed example heating devices include a heater configured to apply heat energy to an object, and control circuitry configured to: control the heater based on a target temperature to which the object is to be heated; in response to beginning to apply heat energy to the object, reset and initialize a timeout counter; in response to determining that a first measured temperature sample associated with a first temperature sensor has increased by at least a threshold amount above a reference temperature, reset the timeout counter and update the reference temperature based on subsequent measured temperature samples; and in response to the timeout counter reaching a threshold count, demote the first temperature sensor from controlling application of heat energy to the object.

[0024] In some examples, the control circuitry is configured to determine the threshold count based on at least one of an identity of the object, a size of the object, or a material of the object. In some examples, the control circuitry is configured to increment a timeout counter in response to receiving the measured temperature sample. In some example heating devices, the timeout counter is configured to increment based on a clock. In some examples, the control circuitry is configured to turn off or ignore the timeout counter in response to the second measured temperature sample satisfying the threshold temperature.

[0025] In some example heating devices, the control circuitry is configured to output a notification that the first temperature sensor is not properly coupled to the object when the timeout counter reaches the threshold count. In some examples, the control circuitry is configured to set a baseline temperature based on at least one of the initial measured temperature or the first measured temperature sample.

[0026] FIG. 1A An example heating system 100 is shown that is configured to control a temperature of an object 108 to be heated based on one or more temperature sensors. The example heating system 100 of FIG. 1 includes an induction heating power supply 102 and an induction heating cable 104. The induction heating power supply 102 heats the object 108 by transmitting induction heating power to the object 108 via the induction heating cable 104, which is disposed proximate to the object 108 to induce a current in the object 108 via magnetic induction from a current in the induction heating cable 104.

[0027] The induction heating power supply 102 supplies induction heating power to the object 108. The induction heating power supply 102 includes power conversion circuitry 110, control circuitry 116, transmitter circuitry 118, a storage device 120, a sensor digitizer 134, a data reader 136, and a user interface 138. The induction heating power supply 102 is coupled to one or more temperature sensors 140 that are configured to measure a temperature of the object 108 at one or more points on the object 108. The example sensor(s) 140 can include a thermocouple, an infrared temperature sensor, a resistance temperature detector, and / or any other type of temperature sensor.

[0028] The example power conversion circuitry 110 converts input power 122 to induction heating power and transmits the induction heating power via the induction heating cable 104. For example, the power conversion circuitry 110 can receive utility and / or generator power, convert the input power 122 to a frequency suitable for heating a particular type of object 108, and transmit the power via the induction heating cable 104. The induction heating cable 104 includes one or more conductors for conducting a current that can be disposed proximate to a workpiece to heat the workpiece by induction.

[0029] The control circuitry 116 can control the power conversion circuit 110 based on the data to, for example, increase and / or decrease the induction heating power output, stop and / or start the induction heating power output, modify the frequency of the induction heating power output, and / or perform any other control or modification.

[0030] The temperature data can be generated from sensor data collected by the one or more sensors 140 and converted to digital data via the sensor digitizer 134 or other sensor monitoring circuitry. The example data reader 136 can be, for example, an RFID reader, a barcode scanner, a QR code scanner, and / or any other type of data reader 136. The example user interface 138 can include any type of user interface device, such as selection buttons, switches, dials, a numeric keypad, a touchscreen, and / or any other type of user interface device.

[0031] The control circuitry 116 controls the power conversion circuit 110 to modify the induction heating power based on data received from the sensor(s) 140 via the sensor digitizer 134. For example, the data can include a measured temperature sample of the object 108.

[0032] The transmitter circuit 118 transmits some or all of the received data to, for example, a local or remote storage device, a local or remote server, and / or any other device. An example recipient of the data transmission can be, for example, a computer or server configured with Insight® software sold by Miller Electric®. Additionally or alternatively, the storage device 120 stores the received data for later retrieval and / or transmission by the transmitter circuit 118. Example transmitter circuits 118 can include wireless communication transmitters (e.g., cellular, Long-Term Evolution (LTE), WiFi, Bluetooth®, etc.) and / or wired communication transmitters (e.g., Ethernet, CAN, USB, etc.). Example storage devices 120 can be an integral storage device such as a hard drive, solid state storage device, or memory device, or a removable storage device such as a USB drive or other connected storage device.

[0033] FIG. 1B is a block diagram of another example heating system 150 that includes a heating power supply 152 and a data collection device 106. The example heating power supply 152 includes a power conversion circuit 110, control circuitry 116, a transmitter circuit 118, and / or a storage device 120 as described above. The example data collection device 106 includes an induction data framer 124, a transmitter circuit 126, a power draw circuit 130, an energy storage device 132, and a filter circuit 142. The example data collection device 106 further includes FIG. 1Asensor digital converter 134, data reader 136, user interface 138. In contrast to the example system 100, the heating system 150 obtains data from the sensor(s) 140 at a location remote from the heating power supply 152 and transmits the data to the heating power supply 152 to control the heating. FIG. 1A

[0034] The receiver circuit 112 is coupled to the induction heating cable 104 and is configured to receive data via the induction heating cable 104. As disclosed in more detail below, the power conversion circuit 110 outputs induction heating power at a first frequency and the receiver circuit 112 receives data at a second frequency different from the first frequency. To separate the data from the induction heating power, the induction heating power supply 152 includes a filter circuit 114 that attenuates the induction heating power. The filter circuit 114 can be a high pass filter and / or a band pass filter for data signals that are significantly higher than the induction heating power frequency. The filter circuit 114 can be a low pass filter for data signals that are significantly lower than the induction heating power frequency.

[0035] While the example filter circuit 114 is shown as being coupled directly to the induction heating cable 104 in parallel with the object 108, in other examples, the filter circuit 114 is coupled directly in series with the induction heating cable 104, inductively coupled to the induction heating cable 104, wirelessly coupled to the induction heating cable 104, and / or connected directly to the induction heating cable 104.

[0036] The example transmitter circuit 126 and the example receiver circuit 112 can communicate using any appropriate modulation scheme. For example, the transmitter circuit 126 and the example receiver circuit 112 can communicate using: orthogonal frequency division multiplexing (OFDM), quadrature amplitude modulation (QAM), frequency shift keying, and / or any other analog, digital, and / or spread spectrum modulation scheme, and / or any combination of modulation schemes. Example techniques that can be implemented by the transmitter circuit 126 and / or the receiver circuit 112 are described in Yonge et al., “An Overview of the HomePlug AV2 Technology,” Journal of Electrical and Computer Engineering, vol. 2013, which is incorporated by reference herein in its entirety. However, the transmitter circuit 126 or the receiver circuit 112 can use other techniques.

[0037] ​The example transmitter circuit 126 transmits induction heating data via an AC signal (e.g., output by the induction heating power supply 102) using a different frequency than the induction heating current frequency on the induction heating cable 104. The example transmitter circuit 126 is coupled to the induction heating cable 104 via the coupling circuit 128 and the filtering circuit 142. The filtering circuit 142 enables the frequency transmitted by the transmitter circuit 126 to be output to the coupling circuit 128 while attenuating the frequency of the induction heating power. FIG. 1B The example coupling circuit 128 includes a current transformer that is magnetically coupled to the induction heating cable 104.

[0038] The power draw circuit 130 draws power from the induction heating cable 104 via the coupling circuit 128 for powering the transmitter circuit 126, the induction data framer 124, the sensor digitizer 134, the data reader 136, and / or the user interface 138, and / or for charging the energy storage device 132. When the power draw circuit 130 is unable to power the components, the example energy storage device 132 provides power to the transmitter circuit 126, the induction data framer 124, the sensor digitizer 134, the data reader 136, and / or the user interface 138. The example energy storage device 132 can include one or more batteries, one or more capacitors, and / or any other type of energy storage device.

[0039] In some examples, the data collection device 106 can be powered by the induction heating power supply 152 to enable the data collection device 106 to collect and / or transmit data when induction heating power is not being applied to the induction heating cable 104. The power conversion circuit 110 can output a pulse via the induction heating cable 104 to power the data collection device 106. After the pulse is output, the power conversion circuit 110 is powered off and the receiver circuit 112 receives data transmitted from the data collection device via the induction heating cable 104 in response to the pulse.

[0040] In some examples, the inductive heating power supply 152 provides intermittent power to heat the object 108 and receives data at the receiver circuit 112 when power is not provided. In some such examples, communication occurs only when the inductive heating power supply 152 is not outputting inductive heating power, and the control circuitry 116 executes logic to connect or enable the receiver circuit 112 to receive communications when the power supply 152 is not providing heating power. For example, the power conversion circuit 110 outputs inductive heating power via the inductive heating cable 104 for a first time period, reduces or withdraws the inductive heating power for a second time period after the first time period, outputs the inductive heating power again during a third time period after the second time period, and so on. The receiver circuit 112 receives data during the second time period. In some examples, instead of or in addition to including a filter circuit 114 to couple the receiver circuit 112 to the inductive heating cable 104, the inductive heating power supply 152 includes a relay, contactor, or another type of isolation device to selectively connect and disconnect the receiver circuit 112 from the inductive heating cable 104. The control circuitry 116 coordinates the power conversion circuit 110 and the isolation device to connect the receiver circuit 112 when the power conversion circuit 110 is not outputting inductive heating power, and to disconnect the receiver circuit 112 when the power conversion circuit 110 is outputting inductive heating power.

[0041] In contrast, the example heating power supply 152 can be configured to enable and / or connect the receiver circuit 112 to receive data when the inductive heating power supply 152 is outputting inductive heating power, and the control circuitry 116 executes logic to disconnect and / or disable the receiver circuit 112 when the power supply 152 is not providing heating power.

[0042] In some examples, the data collection device 106 is coupled to the inductive heating cable 104 via a cable tap instead of via the coupling circuit 128 to couple the transmitter circuit 126 in parallel with the inductance of the object 108 heated by the inductive heating cable 104.

[0043] In FIG. 1BIn an operational example of system 150, control circuitry 116 enables power conversion circuitry 110 to output inductive heating power at a first frequency via inductive heating cable 104 to heat object 108. As inductive heating power flows through inductive heating cable 104, example power extraction circuitry 130 extracts a portion of the inductive heating power to power inductive data framer 124, transmitter circuitry 126, sensor digitizer 134, data reader 136, and / or user interface 138, and / or energy storage device 132. Sensor digitizer 134 converts signals received from sensors(s) 140 (e.g., voltage signals from thermocouples measuring the temperature of object 108 when it is heated) into digital signals and provides these signals to transmitter circuitry 126. Transmitter circuitry 126 transmits data from sensor digitizer 134 at a frequency different from the frequency of the inductive heating power. For example, transmitter circuitry 126 may transmit data at a frequency several orders of magnitude higher than the frequency of the inductive heating power. The filter circuit 114 allows the received data to be received at the receiver circuit 112, which reads data from the induction heating cable 104. The receiver circuit 112 can store the data in the storage device 120, provide the data to the transmitter circuit 126 for transmission to a data collection server (or other device), and / or provide the data to the control circuit system 116 to control the induction heating.

[0044] In some examples, FIG. 1B The data collection device 106 can be powered by the induction heating power supply 152, enabling it to collect and / or transmit data when no induction heating power is applied to the induction heating cable 104. The power conversion circuit 110 can output pulses via the induction heating cable 104 to power the data collection device 106. After the pulses are output, the power conversion circuit 110 disconnects the power supply, and the receiver circuit 112 receives the data transmitted from the data collection device via the induction heating cable 104 in response to the pulses.

[0045] In some examples, the heating power supply 152 may also transmit data to the data collection device 106 via the induction heating cable 104 (e.g., bidirectional communication between the heating power supply 152 and the data collection device 106). In addition to the example data transmitted from the data collection device to the heating power supply 152 via the induction heating cable 104, the heating power supply 152 may also transmit data such as control or configuration data to the data collection device 106 for implementation by control circuitry at the data collection device 106. Additionally or alternatively, the heating power supply 152 may transmit handshake information for negotiating a connection with the data collection device 106.

[0046] During the heating process, the control circuitry 116 of the power supply 102 or 152 monitors temperature samples from the sensors 140 (e.g., temperature samples received via sensor-to-digital converter 134 or data collection device 106) to control the heating process. For example, the sensors 140 can provide temperature feedback so that the control circuitry 116 can control the heating of the object to a target temperature. However, if the temperature-dependent control loop does not receive accurate temperature feedback, such as when the temperature sensors 140 are thermally decoupled or separated from the object 108, the control loop may continue to apply heat to the object 108 even though the temperature of the object 108 has reached and exceeded the target temperature.

[0047] To reduce or prevent the possibility of overheating of object 108, control circuitry 116 also determines whether sensor(s)140 have become decoupled from object 108, as explained in more detail below. If sensor(s)140 are identified as decoupled from object 108, control circuitry 116 reduces the priority of the decoupled sensor in controlling the heating process. For example, if multiple sensors are used, control circuitry 116 may change to using different sensors, or control circuitry 116 may continue the heating process without modification if it does not rely on the decoupled sensor for feedback. In some examples where multiple sensors (including decoupled sensors) are used simultaneously, control circuitry 116 may reduce the relative weight of the decoupled sensor, demote the decoupled sensor from a primary sensor to a non-primary sensor, completely stop using the decoupled sensor, and / or otherwise reduce the priority of the decoupled sensor and / or the dependence of the heating process control on that decoupled sensor. If the sensor 140 required for temperature feedback of a given heating process is determined by the control circuitry 116 to be decoupled from the object 108, the control circuitry 116 may output a notification or alarm (e.g., via user interface 138, via transmitter circuitry 118, etc.) and control the power conversion circuitry 110 to stop outputting heating energy and / or reduce the heating energy output to a level that will not overheat the object 108.

[0048] Some examples of ways in which the (multiple) sensors 140 may decouple from the object 108 include physically removing contact with the object 108, weakening the thermal coupling with the object 108, or not thermally coupling in the first place. Such decoupling can be manifested, for example, by providing temperature feedback that is significantly lower than the actual temperature of the object 108 and / or experiencing noise due to inconsistent thermal coupling.

[0049] To identify thermal decoupling between sensor 140 and object 108, example control circuitry 116 updates a reference temperature and a temperature range associated with sensor 140 as the temperature measured by sensor 140 increases. The temperature range defines an upper and / or lower temperature limit based on the reference temperature. If a measured temperature sample from the sensor is outside the temperature range, or if the reference temperature stops increasing for a period of time before the object reaches the target temperature, control circuitry 116 determines that sensor 140 has decoupled from object 108 and reduces the priority assigned to sensor 140 for controlling the heating process.

[0050] FIG. 2 It shows that it can be made by FIG. 1A and FIG. 1B The measured temperature value 200 during an example process implemented by the heating system, and the example temperature range(s) 202a to 202d and the reference temperatures(s) 204a to 204d associated with one or more temperature sensors during the heating process.

[0051] like FIG. 2 As shown, temperature ranges 202a to 202d define a lower and upper temperature limit around corresponding reference temperatures 204a to 204d. In some examples, the lower and upper temperature limits defining the temperature ranges 202a to 202d are symmetrical with respect to the reference temperatures 204a to 204d (e.g., the lower temperature limit is X degrees lower than the reference temperature, and the upper temperature limit is X degrees higher than the reference temperature). In some other examples, the temperature ranges may be defined asymmetrically with respect to the reference temperatures (e.g., the lower and upper limits may differ from the reference temperatures by different amounts).

[0052] As the temperature measured by sensor 140 increases, the example control circuit system 116 updates the reference temperatures 204a to 204d and the corresponding temperature ranges 202a to 202d. In some examples, whenever a measured temperature sample is greater than the reference temperature, the reference temperatures 204a to 204d are updated by changing the reference temperature to the new measured temperature sample. Similarly, the temperature range can be updated whenever the reference temperatures 204a to 204d are updated. Therefore, although some example reference temperatures 204a to 204d and the corresponding temperature ranges 202a to 202d are shown, FIG. 2 The example measured temperature value of 200 may result in more updates than shown.

[0053] exist FIG. 1A , FIG. 1B and FIG. 2In the example, when the measured temperature sample is lower than the reference temperature, the temperature range 204a to 204d and the reference temperatures 202a to 202d are not updated. If the measured temperature sample is outside the current temperature range 202a to 202d, or if the reference temperature is not updated before the timeout counter expires (e.g., a predetermined count or duration is reached), the example control circuitry 116 determines that the sensor 140 corresponding to the measured temperature value 200 is decoupled from the object 108.

[0054] In some examples, when the workpiece reaches the target temperature, the control circuit system 116 disables or ignores the timeout counter.

[0055] During heating operation, when the measured temperature sample is below the lower limit of the temperature range 202a to 202d for a given time, the example control circuitry 116 can determine that the sensor 140 has decoupled from the object 108 (e.g., detached). When the measured temperature sample is above the upper limit of the temperature range 202a to 202d for a given time, the example control circuitry 116 can determine that the sensor 140 is experiencing noise, which represents poor thermal coupling between the sensor 140 and the object 108.

[0056] In an example where multiple temperature sensors 140 are used for temperature feedback (e.g., multiple thermocouples attached to different locations on object 108), the control circuitry 116 maintains and updates a respective reference temperature and / or temperature range for each of these temperature sensors. The control circuitry 116 may update a first reference temperature and a first temperature range in response to receiving a temperature sample from a first temperature sensor 140, a second reference temperature and a second temperature range in response to receiving a temperature sample from a second temperature sensor 140, a third reference temperature and a third temperature range in response to receiving a temperature sample from a third temperature sensor 140, and so on.

[0057] In some examples, the control circuitry 116 may maintain a single reference temperature and / or a single temperature range for multiple temperature sensors 140. For example, the control circuitry 116 may update the single reference temperature and / or the single temperature range in response to a temperature sample from any of the multiple temperature sensors being greater than the current reference temperature, such as by updating the reference temperature to be equal to the temperature sample and / or updating the single temperature range based on the temperature sample. Additionally or alternatively, the control circuitry 116 may compare a temperature sample from any of the multiple temperature sensors 140 with a single temperature range (which may be updated based on only one, some, or all of these temperature sensors). If a temperature sample from one of the multiple temperature sensors 140 is outside that range, the example control circuitry 116 may determine that the temperature sensor 140 from which it received the temperature sample is decoupled from object 108.

[0058] FIG. 3A to FIG. 3C A flowchart representing example machine-readable instructions 300 is shown, which can be generated by... FIG. 1A and / or FIG. 1B Example induction heating power supplies 102, 152 execute to control the temperature of the object to be heated based on one or more temperature sensors. Example instruction 300 can be executed by example control circuitry 116. In some examples, control circuitry 116 can implement multiple portions of instruction 300 for multiple temperature sensors 140 in parallel to monitor for thermal decoupling of each of the multiple sensors.

[0059] At box 302, control circuitry 116 determines the target temperature of the workpiece (e.g., object 108). For example, control circuitry 116 can be configured via... FIG. 1A or FIG. 1B The user interface 138 receives the target temperature. At block 304, example control circuitry 116 determines whether heating has started. For example, control circuitry 116 can determine whether the operator has started heating via user interface 138. If heating has not yet started (block 304), control returns to block 302 to determine whether the target temperature has changed.

[0060] When heating has begun (box 304), at box 306, control circuitry 116 determines the initial workpiece temperature via measurements from a temperature sensor. For example, control circuitry 116 may receive the initial temperature measurement from sensor 140. At box 308, control circuitry 116 sets a reference temperature and temperature range to default values ​​based on the initial workpiece temperature. For example, control circuitry 116 may set the reference temperature to be equal to the initial temperature measurement and set the initial temperature range based on the reference temperature, such as + / - 25 degrees relative to the reference temperature. Other values ​​may be used to set the initial temperature range.

[0061] At block 310, control circuitry 116 resets and initializes the timeout counter. If the timeout counter reaches a threshold count, control circuitry 116 determines that the sensor 140 corresponding to the counter has not incremented within an acceptable time (e.g., sensor 140 may not have been thermally coupled to the workpiece before the heating process begins). An example reset value can be 0 or any other predetermined value. The timeout counter can be a clock timer (e.g., a timer operating on a clock circuit or other substantially consistent timer, a clock-incrementing counter, etc.) or a counter that increments based on the number of received samples.

[0062] At block 312, control circuitry 116 controls the heater (e.g., power conversion circuitry 110) based on a target temperature. For example, control circuitry 116 may implement a temperature control loop to raise the workpiece temperature toward the target temperature and / or at a desired rate.

[0063] At block 314, control circuitry 116 receives a measured temperature sample from a temperature sensor. For example, control circuitry 116 may receive the temperature sample via a sensor-to-digital converter 134. At block 316, control circuitry 116 determines whether temperature sensor 140 has been decoupled from workpiece 108. For example, control circuitry 116 may compare the measured temperature sample to a temperature range and / or determine whether a timeout has occurred. FIG. 3B and FIG. 3C Example instructions for implementing box 316 are disclosed in the document.

[0064] Go to FIG. 3B Box 318 is connected to box 316. Control circuitry 116 determines whether the temperature sample (received at box 314) is greater than or less than the temperature range (box 318) or temperature range (box 320). If the temperature sample is neither greater than nor less than the temperature range (box 318 or box 320), then at box 322, control circuitry 116 determines whether the temperature sample is greater than a reference temperature. If the temperature sample is not greater than the reference temperature (box 322), then at box 324, control circuitry 116 determines whether the timeout counter has expired.

[0065] If the temperature sample is within the temperature range (box 318 or box 320) and greater than the reference temperature (box 324), then at box 326, control circuitry 116 resets the timeout counter. At box 328, control circuitry 116 sets the reference temperature based on the temperature sample. In some examples, control circuitry 116 sets the reference temperature equal to the measured temperature sample. At box 330, control circuitry 116 updates the temperature range based on the reference temperature and / or the temperature sample. For example, control circuitry 116 may set the temperature range to have temperature limits above and below the updated reference temperature. After updating the reference temperature and temperature range (boxes 328 and 330), control returns to box 312 to continue controlling the heater.

[0066] If the temperature sample is outside the temperature range (box 318 or 320), or if the timeout counter has expired (box 324), the example control circuitry 116 determines that sensor 140 is thermally decoupled from the workpiece and executes a response procedure. The response procedure may include one or more of the following: reducing the relative weight of the decoupled sensor, degrading the decoupled sensor from a primary sensor to a non-primary sensor, completely disabling the decoupled sensor to support a different sensor, reducing heating to a low level, stopping the output of heating energy, and / or outputting a notification or alarm regarding the decoupled sensor. FIG. 3C The example response process was made public.

[0067] At box 332, the control circuitry 116 outputs a notification that the temperature sensor 140 has been decoupled from the workpiece. For example, the control circuitry 116 may output a visual and / or audible alarm via user interface 138, transmit the notification to an external device via transmitter circuitry 118, and / or otherwise output the notification to the appropriate personnel or system.

[0068] At block 334, control circuitry 116 determines whether the heater control loop is based on temperature sensor 140. For example, when multiple temperature sensors are used for the heating process, control circuitry 116 may implement a heater control loop with the highest temperature sample as the most recent sample (e.g., to reduce the likelihood of heating the workpiece above the target temperature). If the heater control loop is based on temperature sensor 140 (block 334), then at block 336, control circuitry 116 determines whether there are available additional temperature sensors(s). For example, control circuitry 116 may determine whether there are other temperature sensors 140 from which temperature samples have been received during the heating process, and whether these temperature sensors have not yet been determined to be decoupled from the workpiece.

[0069] If multiple additional temperature sensors are available (box 336), then at box 338, control circuitry 116 changes the control of the heater to use a different temperature sensor 140. After changing the control to use a different temperature sensor 140 (box 338), or if the heater control loop is based on a different temperature sensor 140 (box 334), control returns to... FIG. 3A The frame 312 is used to continue controlling the heating process.

[0070] If no additional temperature sensor is available (box 336), then at box 340, control circuitry 116 determines whether a low-energy heating mode will be used. For example, control circuitry 116 may continue to output low energy to reduce or prevent workpiece cooling. In some examples, the low energy level is selected based on workpiece characteristics, such as workpiece thickness, workpiece radius (e.g., for pipe fittings), workpiece material, and / or any other characteristics. If a low-energy heating mode (box 340) will be used, then at box 342, control circuitry 116 controls the heater (e.g., power conversion circuitry 110) based on a predetermined thermal energy. Control then returns to... FIG. 3A Box 314.

[0071] If the low-energy heating mode (box 340) is not used, then at box 344, the control circuitry 116 stops applying heat to the object. For example, the control circuitry 116 can control the power conversion circuitry 110 to stop outputting heat energy. Example instruction 300 can then end.

[0072] Although the examples above are described with reference to induction heating, these examples can be modified for resistance heating, where the heating cable supplies power to the heating element (or acts as the heating element itself), which is connected via I... 2 R-heating is used to heat and thermally couple to the workpiece to be heated. The above example can be modified to communicate via a resistive heating cable based on the applied heating power and / or heating frequency in the heating cable.

[0073] As used herein, the terms “circuit” and “circuit system” refer to physical electronic components (i.e., hardware) and any software and / or firmware (“code”) that can configure, be executed by, and / or otherwise associate with the hardware. As used herein, for example, a particular processor and memory may constitute a first “circuit” when executing a first line or more of code, and a second “circuit” when executing a second line or more of code. As used herein, “and / or” refers to any one or more of the multiple items in the list combined by “and / or”. For example, “x and / or y” refers to any element in 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” refers to any element in 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 used herein, the term "exemplary" means used as a non-limiting example, instance, or illustration. As used herein, the terms "for example" and "likely" list one or more non-limiting examples, instances, or illustrations. As used herein, when a circuit system includes the hardware and code necessary to perform a certain function (if necessary), the circuit system is "capable of operating" to perform that function, regardless of whether the execution of that function is disabled or not enabled (e.g., through user-configurable settings, factory settings, etc.).

[0074] Although this method and / or system has been described with reference to certain embodiments, those skilled in the art will understand that various changes and equivalents can be made without departing from the scope of this method and / or system. Furthermore, many modifications can be made to adapt specific situations or materials to the teachings of this disclosure without departing from the scope of this disclosure. For example, the blocks and / or components of the disclosed examples can be combined, divided, rearranged, and / or otherwise modified. Therefore, this method and / or system is not limited to the specific embodiments disclosed. Instead, this method and / or system will include all embodiments that fall within the scope of the appended claims, both literally and according to the principle of equivalents.

Claims

1. A heating apparatus comprising: a heater configured to apply heat energy to an object; and control circuitry configured to: control the heater based on a target temperature to which the object is to be heated; update a first temperature range and a first reference temperature based on a first measured temperature sample associated with a first temperature sensor in response to determining that the first measured temperature sample is greater than the first reference temperature; repeatedly update a previously updated temperature range and a previously updated reference temperature in response to a new measured temperature sample being greater than the previously updated reference temperature at a time of the respective measured temperature sample; and decrease a priority of the first temperature sensor to control application of the heat energy to the object in response to determining that a second measured temperature sample associated with the first temperature sensor is not within the updated temperature range. the control circuitry is configured to decrease the priority of the first temperature sensor to control application of the heat energy to the object in response to determining that the second measured temperature sample associated with the first temperature sensor and subsequent to the first measured temperature sample is not within the first temperature range.

2. The heating apparatus of claim 1, wherein, the control circuitry is configured to:

3. The heating apparatus of claim 1, wherein, compare the new measured temperature sample to the updated temperature range; and decrease the priority of the first temperature sensor to control application of the heat energy to the object in response to a comparison result that any of the new measured temperature sample is outside the updated temperature range. the control circuitry is configured to not update the previously updated temperature range in response to determining that the first measured temperature sample is not greater than the updated reference temperature.

4. The heating apparatus of claim 1, wherein, the heater comprises power conversion circuitry configured to convert input power to inductive heating power or resistive heating power.

5. The heating apparatus of claim 1, wherein, 6. The heating apparatus of claim 1, further comprising sensor monitoring circuitry configured to receive the first measured temperature sample and the second measured temperature sample, the first temperature sensor comprising at least one of a thermocouple, an infrared temperature sensor, or a resistance temperature detector. the control circuitry is configured to update the first temperature range by setting at least one of a temperature upper limit or a temperature lower limit based on the first measured temperature sample.

7. The heating apparatus of claim 1, wherein, the control circuitry is configured to:

8. The heating apparatus of claim 1, wherein, reset and initialize a timeout counter in response to beginning application of the heat energy to the object; reset the timeout counter based on the first measured temperature sample in response to determining that the first measured temperature sample associated with the first temperature sensor has risen at least a threshold amount above a reference temperature; and decrease the priority of the first temperature sensor to control application of the heat energy to the object in response to the timeout counter reaching a threshold count. the control circuitry is configured to determine the threshold count based on at least one of an identity of the object, a size of the object, or a material of the object.

9. The heating apparatus of claim 8, wherein, the control circuitry is configured to increment the timeout counter in response to receiving a measured temperature sample.

10. The heating apparatus of claim 8, wherein, ​ 11. The heating apparatus of claim 8, wherein, The timeout counter is configured to increment based on a clock.

12. The heating apparatus of claim 1, wherein, The control circuitry is configured to maintain the temperature of the object by controlling application of the thermal energy or to reduce the priority of the first temperature sensor by stopping application of the thermal energy to the object.

13. The heating apparatus of claim 1, wherein, The control circuitry is configured to: update a previously updated temperature range and a previously updated reference temperature based on a third measured temperature sample associated with a second temperature sensor in response to determining that the third measured temperature sample is greater than the updated reference temperature; determine whether control of the heater is based on samples associated with the second temperature sensor; and when control of the heater is based on samples associated with the second temperature sensor, reduce a priority of the second temperature sensor to control application of the thermal energy to the object in response to determining that a third measured temperature sample associated with the second temperature sensor is not within the updated temperature range.

14. The heating apparatus of claim 13, wherein, The control circuitry is configured to continue control of the heater based on the first temperature sensor in response to determining that the third measured temperature sample associated with the second temperature sensor is not within the updated temperature range when control of the heater is based on samples associated with the first temperature sensor.

15. The heating apparatus of claim 1, wherein, The control circuitry is configured to reduce a priority of the first temperature sensor to control application of the thermal energy to the object below a priority of a second temperature sensor to control application of the thermal energy to the object.

16. A heating apparatus comprising: a heater configured to apply thermal energy to an object; and control circuitry configured to: control the heater based on a target temperature to which the object is to be heated; reset and initialize a timeout counter in response to beginning application of the thermal energy to the object; reset the timeout counter and raise a reference temperature based on a first measured temperature sample associated with a first temperature sensor in response to determining that the first measured temperature sample has risen at least a threshold amount above the reference temperature; repeatedly raise the reference temperature in response to a new measured temperature sample being greater than a previously raised reference temperature at a time of a respective measured temperature sample; and reduce a priority of the first temperature sensor to control application of the thermal energy to the object in response to the timeout counter reaching a threshold count.

17. The heating apparatus of claim 16, wherein, The control circuitry is configured to reduce a priority of the first temperature sensor to control application of the thermal energy to the object in response to the timeout counter reaching the threshold count without a measured temperature sample satisfying a threshold temperature.

18. The heating apparatus of claim 16, wherein, The control circuitry is configured to determine the threshold count based on at least one of an identity of the object, a size of the object, or a material of the object.

19. The heating apparatus of claim 16, wherein, The control circuitry is configured to increment the timeout counter in response to receiving a measured temperature sample.

20. The heating apparatus of claim 16, wherein, The timeout counter is configured to increment based on a clock.

21. The heating apparatus of claim 16, wherein, The control circuitry is configured to turn off or ignore the timeout counter in response to a second measured temperature sample satisfying a threshold temperature.

22. The heating apparatus of claim 16, wherein, The control circuitry is configured to output a notification that the first temperature sensor is not properly coupled to the subject when the timeout counter reaches the threshold count.

23. The heating apparatus of claim 16, wherein, The control circuitry is configured to set the reference temperature based on at least one of an initial measured temperature or the first measured temperature sample.

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