POSITIVE TEMPERATURE COEFFICIENT HEATERS AND RADIATION APPLICATIONS THEREFOR

Abstract

A heating device (100), the device (100) comprising: a heating element (109) with a positive temperature coefficient (PTC); and a power controller (107) configured to generate a pulse width modified signal and apply it to the PTC heating element (109), wherein the power controller (107) is configured to vary a current of the pulse width modified signal linearly with respect to a temperature of a space heated by the PTC heating element (109); wherein the PTC heating element (109) is a single-folded PTC heating element (420), the device (100) further comprising a rotating element (421) arranged on one side of the single-folded PTC heating element (420) perpendicular to a fold line of the single-folded PTC heating element (420), wherein the rotating member (421) rotates about an axis to place the PTC heating element (420) in an open state (425) and to close the PTC heating element (420) in a folded state.

Description

INTRODUCTION

[0001] Devices and methods consistent with exemplary embodiments relate to configurations of radiant heaters. In particular, devices and methods consistent with exemplary embodiments relate to the integration of radiant heaters into vehicles.

[0002] US 2016 / 0 046 174 A1 describes a radiant heating device comprising a heater having a heating section that generates heat by being supplied with electrical energy to radiate radiant heat based on the heat supplied by the heating section; a power control unit that controls a power of the heating section; and a maximum power determination unit that determines an upper limit of the power of the heating section depending on a heat load around the heater. The power control unit controls the power of the heating section depending on the heat load so that the upper limit of the power set by the maximum power determination unit is not exceeded.

[0003] CN 1 08 749 519 A describes an electric car and a heating method for the electric car. The electric car comprises an interior, a battery, and a heating device. The heating device comprises an electric heating foil and a control unit. The electric heating foil is placed in the interior and electrically connected to the battery via the control unit. The control unit is adapted to connect or disconnect the battery to supply power to the electric heating foil.

[0004] DE 10 2015 010 286 A1 describes a vehicle with a heating device comprising at least one heating element. The heating element is integrated into a partition element for separating a passenger compartment from another vehicle compartment and / or an exterior area of ​​the vehicle. INTRODUCTION

[0005] One or more exemplary embodiments provide a positive temperature coefficient heater integrated into the vehicle or component. In particular, one or more exemplary embodiments provide a positive temperature coefficient device and methods of application and integration thereof.

[0006] According to the invention, a heating device is provided. The device comprises a positive temperature coefficient (PTC) heating element and a power controller configured to generate and apply a pulse-width-modified signal to the PTC heating element. The power controller is configured to vary a current of the pulse-width-modified signal linearly with respect to a temperature of a space heated by the PTC heating element. The PTC heating element is a singly folded PTC heating element, the device further comprising a rotating element arranged on one side of the singly folded PTC heating element perpendicular to a fold line of the singly folded PTC heating element, the rotating element rotating about an axis to place the PTC heating element in an open state and to close the PTC heating element in a folded state.

[0007] According to the invention, a heating device is further provided. The device comprises a positive temperature coefficient (PTC) heating element and a power controller configured to generate and apply a pulse-width-modified signal to the PTC heating element. The power controller is configured to vary a current of the pulse-width-modified signal linearly with respect to a temperature of a space heated by the PTC heating element. The positive temperature coefficient (PTC) heating element comprises a cylindrical structure including a plurality of fold lines extending around a circumferential axis such that the cylindrical structure expands and contracts along a longitudinal axis of the cylindrical structure.

[0008] According to the invention, a heating device is further provided. The device comprises a positive temperature coefficient (PTC) heating element and a power controller configured to generate and apply a pulse-width-modified signal to the PTC heating element. The power controller is configured to vary a current of the pulse-width-modified signal linearly with respect to a temperature of a space heated by the PTC heating element. The PTC heating element comprises a plurality of sections, wherein the plurality of sections are stacked one above the other in a retracted state, configured to rotate about an axis so as to move from stacked positions in the retracted state to adjacent positions in the expanded state.

[0009] The positive temperature coefficient (PTC) heating element can be integrated into one or more of a back of a headrest, an upper back of a seat, a lower back of a seat, an area under a dashboard, a roof, a visor, and a door.

[0010] The device may also comprise a sliding screen with busbars and an insulating layer disposed between an inner portion of the sliding screen and another PTC heating element. The other PTC heating element may be disposed on the insulating layer.

[0011] The sliding screen can be a sunroof visor integrated into a vehicle roof.

[0012] The device may also include a sliding canopy, a plurality of further PTC heating elements, and an insulating layer disposed between an inner portion facing the canopy and the plurality of PTC heating elements. The plurality of PTC heating elements is disposed on the insulating layer, and a first PTC heating element of the plurality of PTC heating elements may be disposed on a portion of the canopy above a left front seat, and a second PTC heating element of the plurality of PTC heating elements may be disposed on a portion of the canopy above a right front seat.

[0013] A third PTC heating element of the plurality of PTC heating elements may be arranged on a portion of the screen above a left rear seat and a fourth PTC heating element of the plurality of PTC heating elements may be arranged on a portion of the screen above a right rear seat.

[0014] The power controller may be configured to set the current of the pulse width modified signal to 100% when the temperature of the space to be heated is less than a first predetermined value and to set the current of the pulse width modified signal to 0% when the temperature of the space to be heated is greater than a second predetermined value, wherein the second predetermined value is greater than the first predetermined value.

[0015] The power control can be configured to linearly vary the current of the pulse width modified signal when the temperature of a space to be heated is between the first specified value and the second specified value.

[0016] The PTC heating element may comprise a flexible printed circuit. Furthermore, the PTC heating element may comprise one or more of ceramic, silicone rubber, and carbon. The space heated by the PTC heating element may be a vehicle interior, and the temperature may be the temperature of the vehicle interior.

[0017] Further objects, advantages and innovations of the exemplary embodiments will become apparent from the following detailed description of the exemplary embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The disclosed examples are described below in connection with the following drawing numbers, where like numbers denote elements and where: Fig. 1 shows a block diagram of a heating device according to an exemplary embodiment; The Fig. 2A and Fig. 2B shows illustrations of a positive temperature coefficient heating element and a graph illustrating power settings according to cabin air temperature according to aspects of exemplary embodiments; Fig. 3 shows various integrations of a positive temperature coefficient heating element according to several exemplary embodiments; Fig. 4 shows various illustrations of usable positive temperature coefficient heating elements according to several exemplary embodiments; Fig. 5 shows additional illustrations of usable positive temperature coefficient heating elements according to several exemplary embodiments; and The Fig. 6A-6C show illustrations of positive temperature coefficient heating elements integrated into a shield according to exemplary embodiments. DETAILED DESCRIPTION

[0019] A heater is now described with reference to the Fig. 1 - 6C of the accompanying drawings, in which like reference numerals refer to like elements throughout.

[0020] The following disclosure will enable a person skilled in the art to apply the inventive concept. However, the exemplary embodiments disclosed herein are merely exemplary and do not limit the inventive concept to the exemplary embodiments described herein. Furthermore, descriptions of features or aspects of each exemplary embodiment should typically be considered available to aspects of other exemplary embodiments.

[0021] It is also to be understood that when it is stated herein that a first element is "connected," "attached," "formed," or "disposed" to a second element, the first element may be directly connected to, formed directly on, or disposed directly on the second element, or there may be intermediate elements between the first element and the second element, unless it is stated that a first element is "directly" connected to, attached to, formed on, or disposed on the second element.When a first element is configured to "send" or "receive" information from a second element, the first element may send or receive the information directly to or from the second element, send or receive the information over a bus, send or receive the information over a network, or send or receive the information through intermediate elements, unless the first element is configured to send or receive information "directly" to or from the second element.

[0022] Throughout the disclosure, one or more of the disclosed elements may be combined into a single device or one or more devices. Furthermore, individual elements may be provided on separate devices.

[0023] Most vehicles are equipped with a heater core and a blower that forces air through the heater core to transfer heat from the coolant in the heater core to the cabin air system. The heater core and blower heating system requires vents and fans, which take up space within the vehicle. Furthermore, with the development of electric vehicles, engines and engine coolant are no longer needed in vehicles. Therefore, an alternative device for heating a vehicle compartment or cabin will be necessary.

[0024] Radiant heaters offer an alternative to heater cores in vehicle interior or cabin heaters. One type of radiant heater is a positive temperature coefficient (PTC) heater. A PTC heater converts electrical energy into heat and can be flexible, allowing for multiple integration options. However, the PTC heater must be integrated to effectively heat a vehicle while maintaining the aesthetics of the vehicle's interior. Furthermore, effectively heating an interior may require a PTC heater with a larger surface area than available. Thus, the device can also expand and contract, or retract and extend PTC heaters, as needed.

[0025] Fig. 1 shows a block diagram of a heating device according to an exemplary embodiment. As in Fig. 1, according to an exemplary embodiment, the heating device 100 includes a controller 101, a power supply 102, a memory 103, an output 104, a sensor 105, a user input 106, a power controller 107, a communication device 108, and a PTC heating element 109. However, the heating device 100 is not limited to the aforementioned configuration and may be configured to include additional elements and / or omit one or more of the aforementioned elements. The heating device 100 may be implemented as part of a vehicle, as a standalone component, or as a hybrid between a vehicle and a vehicle device.

[0026] The controller 101 controls the overall operation and function of the heater 100. The controller 101 may directly or indirectly control one or more of a power supply 102, a memory 103, an output 104, a sensor 105, a user input 106, a power controller 107, a communication device 108, and a PTC heating element 109 of the heater 100. The controller 101 may include one or more of a processor, a microprocessor, a central processing unit (CPU), a graphics processor, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), state machines, switching circuits, and a combination of hardware, software, and firmware components.

[0027] The controller 101 is configured to send and / or receive information from one or more of the power supplies 102, the memory 103, the output 104, the sensor 105, the user input 106, the power controller 107, the communication device 108, and the PTC heating element 109 of the heater 100. The information may be sent and received via a bus or network, or may be directly read or written to one or more of the power supplies 102, the memory 103, the output 104, the sensor 105, the user input 106, the power controller 107, the communication device 108, and the PTC heating element 109 of the heater 100. Examples of suitable network connections include a Controller Area Network (CAN), a Media Oriented System Transfer (MOST), a Local Area Network (LIN), a Local Area Network (LAN), wireless networks such as Bluetooth and 802.11, and other suitable connections such as Ethernet.

[0028] The power supply 102 supplies power to one or more of the memory 103, the output 104, the sensor 105, the user input 106, the power controller 107, the communication device 108, and the PTC heating element 109 of the heating device 100. The power supply 102 may comprise one or more of a battery, a wall outlet, a capacitor, a solar cell, a generator, a wind energy device, an alternator, etc.

[0029] Memory 103 is configured to store and retrieve information used by heating device 100. The information may include information about the interior cabin temperature or the exterior ambient temperature provided by a sensor 105, a thermometer, or other suitable temperature sensor. Memory 103 may be controlled by controller 101 to store and retrieve information received from one or more sensors 105, as well as computer- or machine-executable instructions for controlling PTC heating element 109.The memory 103 may include one or more floppy disks, optical disks, CD-ROMs (Compact Disc-Read Only Memories), magneto-optical disks, ROMs (Read Only Memories), RAMs (Random Access Memories), EPROMs (Erasable Programmable Read Only Memories), EEPROMs (Electrically Erasable Programmable Read Only Memories), magnetic or optical cards, flash memory, cache memory, and other types of media / machine-readable media suitable for storing machine-executable instructions.

[0030] Output 104 outputs information in one or more forms, including: visual, audible, and / or haptic. Output 104 may be controlled by controller 101 to provide outputs to the user of heater 100. Output 104 may include one or more of a speaker, audio, a display, a centrally located display, a head-up display, a windshield display, a haptic feedback device, a vibration device, a tactile feedback device, a tap feedback device, a holographic display, an instrument light, an indicator light, etc.

[0031] Output 104 may output a notification, including one or more of an audible notification, a light notification, and a display notification. The notification may include information about the activation or deactivation of PTC heating element 109 or heater 100. Output 104 may also display images and information provided by one or more sensors 105. Output 104 may display a graphic illustrating the positions of PTC heating elements 109 and indicating their status, e.g., on, off, power setting, etc.

[0032] Sensor 105 may include one or more of a thermometer, a power sensor, and a temperature sensor. The power sensor may be a current sensor, a voltage sensor, or another sensor that detects the current or other power value of the signal output to PTC heating element 109.

[0033] User input 106 is configured to provide information and commands to heater 100. User input 106 can be used to provide user input, etc., to controller 101. User input 106 can include one or more of a touchscreen, keyboard, soft keyboard, button, motion detector, voice input detector, microphone, camera, trackpad, mouse, touchpad, etc. User input 106 can be configured to receive user input to confirm or dismiss the notification output through output 104. User input 106 can also be configured to receive user input to enable or disable heater 100.

[0034] The power controller 107 may include circuitry configured to control or adjust the voltage and frequency of a power signal applied to the PTC heating element. The power controller 107 may include a signal generator, such as a pulse generator (e.g., a solid-state pulser) and / or an amplifier. Furthermore, the power controller 107 may include a DC-to-DC converter and a pulse generator, such as a solid-state pulse generator. According to one example, the power controller may include a transformer configured to convert the AC voltage supplied by the power supply into an AC voltage and frequency to operate the PTC heating element 109.According to another example, the power controller may include a DC-DC converter configured to convert the power supplied by the power supply into a suitable voltage and frequency to operate the PTC heating element 109.

[0035] The communication device 108 can be used by the heating device 100 to communicate with various types of external devices according to various communication methods. The communication device 108 can be used to send / receive various information, such as information about the vehicle's operating mode and control information for the operation of the heating device 100, to / from the controller 101.

[0036] The communication device 108 may include various communication modules, such as one or more of a telematics unit, a broadcast receiving module, a near-field communication (NFC) module, a GPS receiver, a wired communication module, or a wireless communication module. The broadcast receiving module may include a terrestrial broadcast receiving module with an antenna for receiving a terrestrial broadcast signal, a demodulator, and an equalizer, etc. The NFC module is a module that communicates with an external device located at a nearby distance using an NFC method. The GPS receiver is a module that receives a GPS signal from a GPS satellite and detects a current location.The wired communication module may be a module that receives information over a wired network, such as a local area network, a Controller Area Network (CAN), or an external network. The wireless communication module is a module that connects to an external network using a wireless communication protocol, such as the IEEE 802.11 protocol, WiMAX, Wi-Fi, or IEEE communication protocol, and communicates with the external network. The wireless communication module may further include a mobile communication module that accesses a cellular network and performs communication according to various cellular standards, such as . 3. Generation (3G), partnership project of the 3. Generation (3GPP), Long Term Evolution (LTE), Bluetooth, EVDO, CDMA, GPRS, EDGE or ZigBee.

[0037] The PTC heating element 109 is an electrical device that generates heat when an electric current is passed through the element. The heating element is self-regulating and self-limiting because the electrical resistance of the element increases with the element's temperature. In particular, the PTC heating element 109 may be a flexible substrate and printed with an ink or rubber. The PTC heating element 109 may comprise ceramic-, silicone rubber-, or carbon-based ink applied to a plastic film.

[0038] The Fig. 2A and Fig. 2B show illustrations of a positive temperature coefficient heating element and a graph illustrating power settings according to cabin air temperature according to several aspects of exemplary embodiments.

[0039] With reference to Fig. Figure 2A shows a flexible PTC heating element 201. The PTC heating element 201 includes a pattern printed on a substrate connected to two electrodes configured to supply power to the ink. Upon application of energy, the ink pattern radiates heat.

[0040] With reference to Fig. 2B, an exemplary diagram 210 illustrating the power values ​​of a pulse-width-modified signal applied to the PTC heating elements and the cabin air temperature 211 corresponding to the power values ​​212. The example illustrated in diagram 210 shows that the pulse-width-modified signal is set to full power when the temperature is less than a first predetermined value and is turned off when the temperature is greater than a second predetermined value. Furthermore, the pulse-width-modified signal changes linearly when the temperature is between the first predetermined value and the second predetermined value. In this example, between 0 and 25 degrees Celsius.

[0041] Fig. 3 shows various integrations of a positive temperature coefficient heating element according to several exemplary embodiments.

[0042] With reference to Fig. 3, PTC heating elements 109 may be integrated into one or more of a headliner 301, a door panel 302, and an area under a dashboard 303. Other examples of integration of the PTC heating element 109 may include a dashboard, a steering wheel, a center console, etc. In addition, PTC heating elements 109 may also be integrated into one or more of a back of a headrest 304, an upper back of a seat 305, and a lower back of a seat 306.

[0043] Fig. 4 shows various illustrations of usable positive temperature coefficient heating elements according to several exemplary embodiments.

[0044] With reference to Fig. 4, the PTC heating element 201 is a double-folded PTC heating element 410. The double fold may be a Z-fold. A sliding element 411 is arranged on one or two longitudinal edges of the double-folded PTC heating element 410 perpendicular to the fold lines of the double-folded PTC heating element 410. The sliding element 411 can slide along a guide to bring the double-folded PTC heating element 410 into an expanded state 415 and to retract the double-folded PTC heating element 410 back into a folded state. The sliding element 411 can be actuated by a motor, an actuator, a shape memory alloy, or another electromechanical device, or it can be moved manually.

[0045] The PTC heating element 201 can be configured as a single-fold PTC heating element 420. The single fold can be a half-fold. The single-fold PTC heating element 420 can include a rotating element 421 disposed on one side of the single-fold PTC heating element 420 perpendicular to a fold line of the single-fold PTC heating element 420. The rotating element 421 rotates about an axis 422 of the single fold to bring the single-fold PTC heating element 420 into an open state 425 and to place the PTC heating element into a folded state. The rotating element 421 can be located on the side of the single-fold PTC heating element 420 that does not emit heat or on an edge of the single-fold PTC heating element 420. The rotating element 421 can be actuated by a motor, an actuator, a shape memory alloy, or other electromechanical device, or can be moved manually.

[0046] The PTC heating element 201 can be configured as an accordion-fold PTC heating element 430 with a plurality of folds. The accordion-fold PTC heating element 430 can include two double-jointed arms 431 and 432 arranged on opposite edges of the PTC heating element 201 perpendicular to the fold lines of the PTC heating element.

[0047] The first arm 431 of the double-jointed arms is arranged at one end parallel to the plurality of folds. The first arm 431 may include a first joint 434 at a first end of the first arm and a second joint 433 between the first joint and a second end of the first arm. The first joint is configured to rotate a first or lower portion of the first arm 431 in a counterclockwise direction, and the second joint 433 is configured to rotate a second or upper portion of the first arm 431 in a clockwise direction to extend the PTC heating element to an extended state 435, and the first joint 434 is configured to rotate in a clockwise direction, and the second joint 433 is configured to rotate in a counterclockwise direction to retract the PTC heating element to a folded state.The first arm 431 may be actuated by a motor, actuator, shape memory alloy, or other electromechanical device, or may be moved manually.

[0048] The second arm 432 of the double-jointed arms is disposed at the one end parallel to the plurality of folds on a side opposite the first arm. The second arm 432 may include a first joint 434 at a first end of the second arm and a second joint 433 between the first joint and a second end of the second arm 432. The first joint 434 of the second arm 432 can be configured to rotate clockwise and the second joint 433 of the second arm 432 can be configured to rotate counterclockwise to extend the PTC heating element to the extended state 435, and the first joint 434 of the second arm 432 can be configured to rotate counterclockwise and the second joint 433 of the second arm 432 can be configured to rotate clockwise to retract the PTC heating element to the folded state.The second arm 432 may be actuated by a motor, actuator, shape memory alloy, or other electromechanical device, or may be moved manually.

[0049] Fig. 5 shows additional illustrations of usable positive temperature coefficient heating elements according to several exemplary embodiments.

[0050] With reference to Fig. 5, in one example, the PTC heating element may include a plurality of sections 501-506. The plurality of sections 501-506 may be stacked one upon another in a retracted state 510. The plurality of sections 501-506 may be configured to rotate about an axis or rod 512 to move from the stacked positions 511 in the retracted state 510 to the adjacent positions in the extended state 515. The rod 512 may be actuated by a motor, actuator, shape memory alloy, or other electromechanical device, or may be manually moved.

[0051] In another example, the PTC heating element may include a cylindrical structure 532. The cylindrical structure 532 may include a plurality of fold lines 521 extending around a circumferential axis such that the cylindrical structure 530 expands and contracts 520 along a longitudinal axis of the cylindrical structure 532. Alternatively, the cylindrical structure 532 may expand and retract along an arc, as shown in Fig. The cylindrical structure 532 of the element can be expanded or contracted by a motor, actuator, shape memory alloy, or other electromechanical device, or can be moved manually.

[0052] In yet another example, a box 543 containing consumables, food, or medical supplies requiring a temperature-controlled environment may be placed within a container or space 540. The container or space may be integrated into a vehicle. One or more of the interior walls (e.g., top, bottom, left, right) of the container 540 may be lined with the PTC heating element 542.

[0053] The Fig. 6A-6C show illustrations of positive temperature coefficient heating elements integrated into a shadow, according to several aspects of an exemplary embodiment.

[0054] Related to Fig. 6A, a sliding screen 606 is shown. The sliding screen 606 can cover a moonroof, a sunroof, or other window of a vehicle. In the Fig. 6A, the sliding shade 606 slides over a roof 601 of a vehicle. The sliding shade 606 may include bus bars 602 and an insulating layer 604 disposed between an interior attachment 603 of the sliding shade 606 and a PTC heating element 605. The PTC heating element 605 may be disposed on the insulating layer 604. The sliding shade 606 may transition from a closed position 610 to an open position 620 by sliding or rolling along guides, tracks, or other mechanisms. The sliding shade 606 may be actuated by a motor, actuator, shape memory alloy, or other electromechanical device, or may be manually moved.

[0055] With reference to Fig. 6B, a roller shade 606 is shown. The roller shade 606 may cover a sunroof, a moonroof, or other window of a vehicle. The roller shade 606 may include bus bars 602 and an insulating layer disposed between an interior portion facing the portion 603 of the roller shade 606 and the PTC heating element 605. The PTC heating element 605 may be disposed between the bus bars 602. The insulating layer is optional, and in one example, the insulating layer may be omitted. The roller shade 606 may transition from a closed position 630 to an open position 640 by being rolled onto the rolling rod 607. The rod 607 may be actuated by a motor, actuator, shape memory alloy, or other electromechanical device, or may be manually moved.

[0056] With reference to Fig.6C illustrates a zoned PTC heating system 650. A canopy 603 having a plurality of PTC heating elements (651-654) is illustrated. An insulating layer 604 disposed between an interior portion of the canopy and the plurality of PTC heating elements (651-654) is illustrated. The plurality of PTC heating elements (651-654) are disposed on the insulating layer 604. The canopy may be a sunroof, a moonroof, or a panoramic roof disposed within a vehicle roof 601.

[0057] A first PTC heating element 651 from the plurality of PTC heating elements (651-654) is arranged on a portion of the screen above a left front seat, and a second PTC heating element 652 from the plurality of PTC heating elements (651-654) is arranged on a portion of the screen above a right front seat. Furthermore, a third PTC heating element 653 from the plurality of PTC heating elements (651-654) is arranged on a portion of the screen above a left rear seat, and a fourth PTC heating element 654 from the plurality of PTC heating elements (651-654) is arranged on a portion of the screen above a right rear seat.

[0058] The processes, methods, or algorithms disclosed herein may be delivered to or implemented by a processing device, controller, or computer, which may include an existing programmable electronic control device or a dedicated electronic control device. Likewise, the processes, methods, or algorithms may be stored as data and instructions executable by a controller or computer in many forms, including, but not limited to, information permanently stored on non-writable storage media such as ROM devices and information modifiably stored on writable storage media such as floppy disks, magnetic tapes, CDs, RAM devices, and other magnetic and optical media. The processes, methods, or algorithms may also be implemented in an executable software object.Alternatively, the processes, methods or algorithms may be represented in whole or in part using suitable hardware components such as Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), state machines, controllers or other hardware components or devices or a combination of hardware, software and firmware components.

[0059] One or more exemplary embodiments have been described above with reference to the drawings. The exemplary embodiments described above are to be considered in an illustrative sense only and not for purposes of limitation. Furthermore, the exemplary embodiments may be modified without departing from the spirit and scope of the inventive concept defined by the following claims.

Claims

[1] A heating device (100), the device (100) comprising: a heating element (109) with a positive temperature coefficient (PTC); and a power controller (107) configured to generate a pulse width modified signal and apply it to the PTC heating element (109), wherein the power controller (107) is configured to vary a current of the pulse width modified signal linearly with respect to a temperature of a space heated by the PTC heating element (109); wherein the PTC heating element (109) is a single-folded PTC heating element (420), the device (100) further comprising a rotating element (421) arranged on one side of the single-folded PTC heating element (420) perpendicular to a fold line of the single-folded PTC heating element (420), wherein the rotating member (421) rotates about an axis to place the PTC heating element (420) in an open state (425) and to close the PTC heating element (420) in a folded state. [2] The device (100) of claim 1, wherein the positive temperature coefficient (PTC) heating element (420) is integrated into one or more of a back of a headrest (304), an upper back of a seat (305), a lower back of a seat (306), an area under a dashboard (303), a roof, a visor, and a door. [3] The device (100) of claim 1, wherein the power controller (107) is configured to set the current of the pulse width modified signal to 100% when the temperature of the space to be heated is less than a first predetermined value, and to set the current of the pulse width modified signal to 0% when the temperature of the space to be heated is greater than a second predetermined value, the second predetermined value being greater than the first predetermined value. [4] A heating device (100), the device (100) comprising: a heating element (109) with a positive temperature coefficient (PTC); and a power controller (107) configured to generate a pulse width modified signal and apply it to the PTC heating element (109), wherein the power controller (107) is configured to vary a current of the pulse width modified signal linearly with respect to a temperature of a space heated by the PTC heating element (109); wherein the positive temperature coefficient (PTC) heating element (109) comprises a cylindrical structure (532) comprising a plurality of fold lines extending about a circumferential axis such that the cylindrical structure (532) expands and contracts along a longitudinal axis of the cylindrical structure (532). [5] A heating device (100), the device (100) comprising: a heating element (109) with a positive temperature coefficient (PTC); and a power controller (107) configured to generate a pulse width modified signal and apply it to the PTC heating element (109), wherein the power controller (107) is configured to vary a current of the pulse width modified signal linearly with respect to a temperature of a space heated by the PTC heating element (109); wherein the PTC heating element (109) comprises a plurality of sections (501-506), and wherein the plurality of sections (501-506) are stacked one above the other in a retracted state, configured to rotate about an axis (512) so as to move from stacked positions (511) in the retracted state (510) to adjacent positions in the expanded state (515).

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