Method for providing thermal contrast therapy

Abstract

A method for providing thermal contrast therapy to a vehicle occupant. The method comprises firstly operating a heating device to apply a first temperature for a first period of time, and secondly operating the heating device and a cooling device alternately for a plurality of time intervals. The thermal contrast therapy achieves a temperature change of approximately 10°C to 20°C on the surface of a seat and / or a change in the skin temperature of the vehicle occupant of approximately 3°C to 6°C.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Application No. 17 / 957,871, filed September 30, 2022, and U.S. Provisional Application No. 63 / 537,083, filed September 7, 2023, both of which are incorporated by reference in their entirety into this application. TECHNICAL FIELD

[0002] The present disclosure relates to a method for performing thermal contrast therapy through a vehicle seat. BACKGROUND

[0003] There are proposals for pain relief through vehicle seats. In some cases, massage devices have been used in vehicle seats to alleviate occupant discomfort or even pain. Some vehicle seats incorporate heating and / or cooling devices in addition to the massage devices. However, massage devices typically require a lot of space in the seats, thus increasing the overall cost of the vehicle. Managing space and costs is a constant problem in the automotive industry.

[0004] Heat therapy is a well-known method for pain relief. Heat therapy is generally performed by alternately heating and cooling the body, often by immersion in a temperature-controlled water bath. Heat therapy can be used for pain relief, injury treatment, and recovery from sports and exercise. These effects are due to increased blood flow to the target area through vasoconstriction and vasodilation, which are influenced by periods of cooling and heating, respectively. Furthermore, the acute application of heat can activate thermoreceptors and desensitize pain receptors. Other physiological effects include a reduction in inflammation and / or increased mobility.

[0005] Current clinical studies have investigated heat therapy in general. However, no operating parameters for heating and cooling devices in vehicle seats have been proposed. Furthermore, no time constraints for achieving pre- and post-treatment effects that correspond to typical travel times (e.g., 15-25 minutes) have been proposed. Current clinical studies have not yet investigated the role of the magnitude and rate of skin temperature change in therapy.

[0006] There is a need for a method to provide pain relief for vehicle occupants without the use of massage devices.

[0007] There is a need for a method of providing pain relief to vehicle occupants using only the existing heating and cooling devices in the vehicle seats.

[0008] There is a need for a method for heat therapy in vehicles.

[0009] There is a need to operate heating and cooling devices with specific time and temperature profiles to provide effects to the occupants during and / or after treatment.

[0010] There is a need for heating and cooling devices that target specific areas of the occupants' bodies.

[0011] There is a need for heat therapy that takes into account the clothing worn by inmates during cold and warm seasons. SUMMARY

[0012] The present disclosure describes a method for providing thermal contrast therapy to a vehicle occupant that may meet at least some of the above requirements. The method may include first operating a heating device to apply a first temperature for a first period of time, and second, operating the heating device and a cooling device alternately for a plurality of time intervals.

[0013] Operating the heating device at the first temperature during the first period of time may bring the temperature of at least a portion of the seat surface to about 43°C to 48°C and / or the skin temperature of the vehicle occupant in an area of ​​the at least one portion to about 36°C or more.

[0014] During the plurality of time intervals, the heating device may be operated for a second period of time. The second period of time may be approximately 3 to 5 minutes. During the plurality of time intervals, the cooling device may be operated for a third period of time. The third period of time may be approximately 3 to 6 minutes.

[0015] Thermocontrast therapy can achieve a temperature change of at least one section of the seat surface of approximately 10°C to 20°C and / or a change in the skin temperature of the vehicle occupant in the area of ​​at least one section of the seat surface of approximately 3°C to 6°C.

[0016] During the plurality of time intervals, the heating device and the cooling device can cause temperature changes in the at least one portion of the seating surface. The at least one portion can include a lower portion, a middle portion, an upper portion, or any combination thereof.

[0017] The heating device may be located in the lower and middle sections, and during the plurality of time intervals, the heating device in the lower section may be brought to a target temperature of approximately 63°C to 67°C (e.g., 65°C) and the heating device in the middle section may be brought to a target temperature of approximately 77°C to 83°C (e.g., 80°C).

[0018] The heating device may be located in the upper section and during the plurality of time intervals the heating device in the upper section may be brought to a target temperature of approximately 67°C to 73°C (e.g., 70°C).

[0019] During the several time intervals, the cooling device can be brought to a target temperature of approximately 18°C ​​to 22°C (e.g. 20°C).

[0020] During the multiple time intervals, the heating device can be operated by pulse-width modulation with a duty cycle of approximately 55% to 65% (e.g., 60%). During the multiple time intervals, the cooling device can be operated by pulse-width modulation with a duty cycle of approximately 85% to 95% (e.g., 90%).

[0021] The operating time of the heating device and the cooling device can be the same during the several time intervals.

[0022] The rate of temperature change during the multiple time intervals can be ± 0.4°C / minute to ± 0.9°C / minute for skin temperature and / or ± 1°C / minute to ± 2.5°C / minute for seat temperature.

[0023] The multiple time intervals can last from about 20 to 35 minutes.

[0024] The alternating heating and cooling can each be characterized by a ramp and step profile. The ramp and step profile of the heating can be inverse to the ramp and step profile of the cooling.

[0025] There should be no idle time between the alternating operation of the heating and cooling systems. The idle time can be characterized by a period during which both the heating and cooling systems are not in operation.

[0026] The heater can be operated by pulse width modulation with a duty cycle of about 55% to 65% (e.g. 60%) to reach the first temperature.

[0027] The first temperature can be about 55°C to 90°C.

[0028] The first period can be about 5 to 10 minutes.

[0029] The time intervals can contain 6 to 16 time intervals.

[0030] Heat contrast therapy can be adapted to relieve the pain of the vehicle occupant.

[0031] The temperature of the at least one portion of the seat surface and / or the skin temperature of the vehicle occupant may be determined by a dynamic estimation that takes into account one or more heat transfer rates relative to the at least one portion of the seat surface and / or the skin temperature of the vehicle occupant.

[0032] The at least one portion of the seating surface may comprise a lower portion and / or a middle portion.

[0033] The present disclosure describes a device that can meet at least some of the above-mentioned needs. The device can perform the method described above. The device can include the heating device located in an upper portion of the seat, a middle portion of the seat, and a lower portion of the seat, as well as a cooling device acting on the middle portion of the seat.

[0034] The heating device may comprise a resistive element. The cooling device may comprise a fan, a thermoelectric device, a fluid distribution device, or any combination thereof.

[0035] The heating device in the lower section can achieve a surface power density of about 2,100 to 2,500 W / m 2 The heating device in the middle section can have a surface power density of approximately 1,900 to 2,300 W / m 2The heating device in the upper section can have a surface power density of approximately 900 to 1,500 W / m 2 have.

[0036] The present disclosure describes a vehicle seat that can meet at least some of the above-mentioned needs. The vehicle seat may include the device described above. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic representation of a vehicle seat. Fig. Figure 2A is a graph of skin temperature versus time during the control experiment according to the present teachings. Fig. Figure 2B is a graph of seat surface temperature over time during the control test according to the present teachings. Fig. Figure 3A is a graph of the heater and cooler target temperatures over time during testing according to the present teachings. Fig.Figure 3B is a diagram of the heating and cooling device duty cycles during the experiment according to the present teachings. Fig. Figure 3C is a graph of skin temperature versus time during the experiment according to the present teaching. Fig. 3D is a graph of seat surface temperature over time during the test according to the present teaching. Fig. Figure 3E is a graph of changes in skin temperature over different time intervals during the experiment according to the present teaching. Fig. Figure 3F is a graph of changes in seat surface temperature over various time intervals during testing according to the present teachings. Fig. is a graph of subjective pain in the control study. Fig. is a diagram of subjective pain for the experimental trial. Fig.Figure 5 is a schematic representation of a system according to the present teachings. Fig. 6 is a schematic representation of a system according to the present teachings. Fig. Figure 7 is a schematic representation of a system according to the present teachings. DESCRIPTIONIntroduction.

[0037] The present teaching relates to a method for providing thermal contrast therapy, a device for performing thermal contrast therapy, and a vehicle seat with this device. In thermal contrast therapy, a human subject (e.g., a vehicle occupant) can be alternately heated and cooled. Thermal contrast therapy can be applied to the back of humans.

[0038] Thermal contrast therapy can be delivered using one or more heating and cooling devices. The target temperatures and operating times of the heating and cooling devices can be selected to modulate the temperature of a seating surface, to modulate a person's skin temperature, to achieve a clinically significant effect (reduction) in a person's pain level, to ensure that the person feels a temperature difference, or any combination thereof.

[0039] The target temperatures and operating times of the heating and cooling devices can be selected to realize the relationship between heating and cooling periods, temperature gradients, temperature change rates of the seat surface, temperature change rates of the human skin, or any combination thereof.

[0040] The target temperatures and operating times of the heating and cooling devices can be adjusted according to seasonal and / or regional climate conditions, which may vary in terms of ambient temperature, humidity, etc. This means that the thermal insulation of clothing worn in different seasons and / or regions can be taken into account. For example, the target temperature and operating time may be different in the fall and winter months, when thicker layers of clothing are typically worn, than in the spring and summer months, when thinner layers are typically worn. Furthermore, the present method can take into account the regions in which the vehicles are located.For example, a seasonal difference in the thermal insulation of clothing layers cannot be taken into account in regions with a tropical climate due to relatively constant weather conditions throughout the year, but can be taken into account in regions with a continental climate where the weather fluctuates throughout the year.

[0041] Heat contrast therapy can provide pain relief ("analgesia") to people (e.g., vehicle occupants). Analgesia can be achieved during heat contrast therapy and / or after heat contrast therapy. Analgesia can occur 0.5 hours or less, 1 hour or less, 2 hours or less, 3 hours or less, or even 6 hours or less after heat contrast therapy.

[0042] Heat contrast therapy can be directed to the back, buttocks, or thighs of people, or any combination thereof. Heat contrast therapy can be directed to the upper back, mid-back, lower back, or any combination thereof. It may be beneficial to apply heat contrast therapy to at least the lower back, which is most commonly affected by acute or chronic pain. Furthermore, the heat contrast therapy of the present teachings can be applied through a seat (e.g., a vehicle seat), where pressure exerted by the occupants may be concentrated on the lower and / or mid-back.

[0043] The person can select any body part and / or parts thereof for thermal contrast therapy. One or more body parts and / or parts of the body can be targeted. Multiple body parts and / or sections can be brought to the same or different skin temperatures.

[0044] Habitual use of thermal contrast therapy (e.g., during the morning and / or evening commute) may provide additional benefits for individuals. That is, the magnitude of change in pain level (compared to the pain level without thermal contrast therapy) during and / or after thermal contrast therapy may increase in proportion to the frequency of use. Furthermore, the duration of pain reduction (compared to pain without thermal contrast therapy) after cessation of thermal contrast therapy may increase in proportion to the frequency of use.

[0045] Although the present disclosure describes the therapy duration in the context of typical travel times, thermal contrast therapy according to the present disclosure can also be continued for shorter or longer periods. For example, during long journeys, thermal contrast therapy can be applied for 0.5 hours or more, 1 hour or more, 2 hours or more, or even 3 hours or more. According to the present disclosure, thermal contrast therapy can be applied multiple times during a single journey. There may or may not be a period of non-application between each therapy session. Device.

[0046] Thermal contrast therapy can be administered in vehicles. Vehicles may include one or more seats with heating and / or cooling devices. The heating and / or cooling devices can be set to predetermined target temperatures and operating times to deliver thermal contrast therapy according to the present teachings. One or more heating and / or cooling devices can be arranged in different sections of a vehicle seat, thus applying thermal contrast therapy to different regions of an occupant's body.

[0047] The vehicle seat may include a back portion and a seat portion. The back portion and / or the seat portion may have one or more heating devices and / or one or more cooling devices. One or more heating and / or cooling devices may be arranged in one or more sections of the vehicle seat. Each seat portion may be contacted by a different body region of an occupant. A single heating and / or cooling device may include one or more zones. The zones may be capable of operating independently of one another. The one or more zones may be arranged in one or more sections of the vehicle seat.

[0048] The backrest and / or seat portion may include one or more bolsters. The neck rolls may extend at least partially beyond the body profile of an occupant. The bolsters may extend at an angle relative to a seat surface and / or backrest surface. The bolsters may serve to at least partially cushion the occupants' lateral movement during driving (e.g., when cornering). One or more areas of an occupant's body may rest against one or more bolsters. One or more areas of an occupant's body may exchange heat with one or more bolsters.

[0049] The lower, middle, and upper sections referred to herein may be part of the back of the vehicle seat. Generally, the lower section extends over the region of the back containing the lumbar vertebral segment, the middle section extends over the region of the back containing the T7-T12 vertebral segment, and the upper section extends over the region of the back containing the T1-T6 vertebral segment. The present disclosure recognizes that occupants may have different body measurements, and therefore, one skilled in the art may adapt the present teachings so that the above-described divisions between the lower, middle, and upper sections may vary accordingly.

[0050] The heating and / or cooling devices may be located beneath a surface of the vehicle seat. One or more layers of material (e.g., fabric, foam, film, and the like) may be disposed between the heating and / or cooling devices and the seat surface. The heating and / or cooling devices may provide a sensation of heat to the occupants through conduction and / or convection. With conduction, heat may be conducted through one or more layers of the vehicle seat and ultimately to an occupant contacting the surface of the vehicle seat. With convection, heated and / or cooled air may flow through one or more layers of the vehicle seat, and the air may come into contact with the occupant.

[0051] The heating devices may consist of one or more resistive elements. The resistive elements may have a negative temperature coefficient, a positive temperature coefficient, a constant temperature coefficient, or any combination thereof. The resistive elements may heat up when a current is applied to them. The resistive elements may be supported on a medium. The medium may be a film, a nonwoven mat, a woven mat, or any combination thereof.

[0052] An exemplary heating device is described in U.S. Patent No. 9,315,133 B2, which is incorporated herein by reference in its entirety for all purposes.

[0053] The heating devices can be adapted to the section of the vehicle seat in which they are located. The heating devices in different sections of the vehicle seat can have different surface power densities. A lower and / or middle section of a backrest can be equipped with a higher surface power density than an upper section of a backrest. In this context, thermal contrast therapy can be concentrated on the lower and middle regions, as these areas of the back are often affected by acute and / or chronic pain. The present teaching provides that all sections of the seat have the same surface power density or that the upper section has a greater surface power density than the lower and / or middle sections.

[0054] A heating device located in the lower part of a seat back can have a surface power density of about 1,100 W / m 2 or more, 1,300 W / m 2 or more, 1,500 W / m 2 or more or even 1,700 W / m 2 or more. A heating device in the lower area of ​​a seat back can have a surface power density of about 2,500 W / m 2 or less, 2,300 W / m 2 or less, 2,100 W / m 2 or less or even 1,900 W / m 2 or less

[0055] A heating device located in the central area of ​​a vehicle seat back can have a surface power density of approximately 1,100 W / m 2 or more, 1,300 W / m 2 or more, 1,500 W / m 2 or more or even 1,700 W / m 2or more. A heating device located in a central section of a seat back may have a surface power density of approximately 2,300 W / m 2 or less, 2,100 W / m 2 or less or even 1,900 W / m 2 or less.

[0056] A heating device located in the upper part of a vehicle seat back can have a surface power density of about 900 W / m 2 or more, 1,000 W / m 2 or more or even 1,100 W / m 2 or more. A heating device located in the upper area of ​​a vehicle seat back can have a surface power density of about 1,500 W / m 2 or less, 1,400 W / m 2 or less or even 1,300 W / m 2 or less.

[0057] A heating device in the upholstery of a vehicle seat can have a surface power density of about 800 W / m 2 or more, 900 W / m 2or more or even 1,000 W / m 2 or more. A heating device in the upholstery of a vehicle seat can have a surface power density of about 1,400 W / m 2 or less, 1,300 W / m 2 or less or even 1,200 W / m 2 or less.

[0058] The above power densities may be the maximum power densities of the heaters. As described here, the duty cycle may be less than 100%. Therefore, the effective power densities of the heaters during operation may be lower than the maximum power densities in accordance with the duty cycle realized during operation. For example, a heater with a maximum power density of 2,400 W / m 2 an effective power density of 1,200 W / m 2 when operated at a duty cycle of 50%.

[0059] The surface power density of the heater in the lower section may be approximately 5% or more, 7% or more, or even 9% or more greater than the surface power density of the heater in the middle section. The surface power density of the heater in the lower section may be approximately 15% or less, 13% or less, or even 11% or less greater than the surface power density of the heater in the middle section. The surface power density of the heater in the lower section may generally be equal to the surface power density of the heater in the middle section.

[0060] The surface power density of the heater in the middle section and / or lower section may be approximately 40% or more, 45% or more, or even 50% or more greater than the surface power density of the heater in the upper section. The surface power density of the heater in the middle section and / or lower section may be approximately 65% ​​or less, 60% or less, or even 55% or less greater than the surface power density of the heater in the upper section.

[0061] The cooling devices may include one or more fans, ducts, fluid distribution devices, thermoelectric devices, or any combination thereof.

[0062] The blower can draw in air (e.g., from under and / or behind a vehicle seat) and deliver air to one or more fluid distribution devices. The blower can be an axial fan or a centrifugal fan. Non-limiting examples of blowers are described in International Publication No. WO 2008 / 115831 A1 and US Patent No. 9,121,414 B2, which are incorporated herein by reference for all purposes.

[0063] One or more conduits may extend between the blower and one or more fluid distribution devices. The one or more conduits may transport air between the blower and the one or more fluid distribution devices.

[0064] The fluid distribution devices can be arranged below the surface of a vehicle seat. One or more layers of material (e.g., fabric, foam, film, etc.) can be arranged between the fluid distribution devices and the surface of the vehicle seat.

[0065] The fluid distribution devices may comprise an enclosure (e.g., a bag). The enclosure may be formed by one or more material segments. For example, two material segments may be secured by a seam around the perimeter of the enclosure. Another example is that the enclosure is formed by a single material segment.

[0066] The air supplied by one or more fans can enter the housing. The housing can be at least partially hermetically sealed. The housing can have one or more openings. The air can exit the housing through the one or more openings. The one or more openings can discharge air onto a surface of a vehicle seat.

[0067] The fluid distribution devices may be in conductive and / or convective thermal communication with an occupant. Heated or cooled air within the enclosure may be in conductive thermal communication with the walls of the enclosure, the walls may be in conductive thermal communication with one or more material layers of a seat disposed between the enclosure and the seat surface, the seat surface may be in conductive thermal communication with an occupant, or any combination thereof. Heated or cooled air may flow through the enclosure through one or more openings, flow through one or more openings extending through one or more layers of the seat and / or seat surface, convectively thermally communicate with an occupant, or any combination thereof. One or more openings may direct air to a location other than the surface of the seat.One or more openings may be part of a fluid circuit that returns the air to the fan inlet.

[0068] The fluid distribution devices may be located in a lower, upper, or middle region of a vehicle seatback, or any combination thereof. The fluid distribution devices may be located in seating areas subject to pressure from the occupants. The fluid distribution devices may discharge air from a lower, upper, or middle region of a vehicle seatback, or any combination thereof.

[0069] The air supplied to the enclosure can be heated and / or cooled. The air can be heated and / or cooled by one or more thermoelectric devices. The thermoelectric device(s) can be located in one or more fans, ducts, enclosures, or any combination thereof.

[0070] The thermoelectric devices may be Peltier devices. The thermoelectric devices may have two surfaces, one of which is the "hot" side and the other of which is the "cold" side relative to each other. By reversing the polarity of the energy supplied to the thermoelectric component, the relative temperatures of the two sides can be reversed. A non-limiting example of a thermoelectric device is described in U.S. Patent No. 9,857,107 B2, which is incorporated herein by reference for all purposes.

[0071] The cooling device can be configured to provide additional heat to the heating device. In this context, the polarity of one or more thermoelectric devices can be switched to convert the cold side into the hot side. Procedure.

[0072] The present disclosure describes a method for providing thermal contrast therapy to a vehicle occupant. The thermal contrast therapy may be designed to alleviate the vehicle occupant's pain. The pain may be alleviated during and / or after treatment.

[0073] The method of the present disclosure may include operating a heating device to apply a first temperature for a first period of time. The first temperature may be about 55°C to 90°C. The first period of time may be about 5 to 10 minutes. Operating the heating device at the first temperature during the first period of time may overcome the thermal inertia of a vehicle seat and / or raise the skin temperature of an occupant to therapeutic levels. The temperature during the first period of time may be higher than the temperature during the multiple time intervals described further below.

[0074] The temperature of the heating device referred to here may be understood to mean the temperature of the resistance element (e.g. a resistance element with a negative temperature coefficient).

[0075] The heater can be operated by regulating the power supplied to it. The power can be controlled by pulse-width modulation (PWM), constant current control, or similar. The heater can be operated with a duty cycle of at least about 60%, at least about 70%, at least about 80%, at least about 90%, or even 100% to reach the first temperature.

[0076] The heating device can be operated during the initial period to bring the temperature of at least a portion of the seat surface to about 43°C to 48°C and / or the skin temperature of a vehicle occupant to about 34°C to 40°C. Preferably, the skin temperature is brought to about 36°C or more, which is considered therapeutic but below the pain / burn threshold. The at least one portion can comprise a lower, middle, and / or upper portion. Preferably, the at least one portion can comprise a lower and / or middle portion. The skin temperature of the vehicle occupant can be the skin temperature of the portion of skin that comes into contact with the lower, middle, and / or upper portion (directly or indirectly through clothing located between the seat surface and the skin).

[0077] Therapy can be performed on the occupant's spine and / or an area near the spine. Therapy can be performed across the back, at least partially from one side of the back to the opposite side of the back, and in sections that run at different heights along the spine.

[0078] A temperature of 43°C is typically considered the threshold at which occupants may experience pain, and a temperature of 44°C is typically considered the threshold at which occupants may sustain a burn. While seat surface temperatures exceed these pain / burn thresholds, the time the pain / burn thresholds are exceeded (e.g., 2 minutes or less), the rate of temperature change (e.g., no more than 0.5°C / minute, according to Carter et al., Sensory and sympathetic nerve contributions to the cutaneous vasodilator response from a noxious heat stimulus, Exp. Physiol. 96.11:1208-1217), the thermal insulation of participants' clothing (e.g., at least about 0.05 Clo), or any combination thereof may preclude a pain / burn response in participants.

[0079] The method may involve operating the heating device and a cooling device alternately for a plurality of time intervals. The number of time intervals may be 6 or more, 8 or more, or even 10 or more time intervals. The number of time intervals may be 16 or fewer, 14 or fewer, or even 12 or fewer time intervals.

[0080] During each of the time intervals, the heating device may be in operation for approximately 3 to 5 minutes. During each of the time intervals, the cooling device may be in operation for approximately 3 to 6 minutes. The operating time of the heating device and the cooling device during the multiple time intervals may be equal or unequal. The operating times of the heating device and the cooling device may or may not overlap. In each time interval, there may be a period of time during which either the heating device or the cooling device is in operation and the other device is not in operation.

[0081] The multiple time intervals can last for approximately 20 to 35 minutes or until the process is completed. The vehicle occupant can manually terminate operation. A fault condition can automatically terminate operation (e.g., overheating beyond a threshold temperature and / or exceeding a threshold temperature for a predefined period of time).

[0082] There may or may not be an idle time between the alternating operation of the heating and cooling devices. An idle time may be characterized by a period of time during which both the heating and cooling devices are not operating.

[0083] The alternating heating and cooling can each be characterized by a ramp and step profile. The ramp and step profile can manifest itself as a steep temperature rise, a temperature hold for a certain period, and a steep temperature drop. The ramp and step profile of heating can be opposite to the ramp and step profile of cooling.

[0084] Thermal contrast therapy can cause a change in the temperature of the seat surface by approximately ± 10°C to ± 20°C and / or a change in the skin temperature of the vehicle occupant by approximately ± 3°C to ± 6°C. The magnitude of the change can promote vasodilation and vasoconstriction in the occupants.

[0085] The rate of temperature change during the multiple time intervals may be approximately (±0.2) ± 0.4°C / minute to ± 0.9°C / minute for skin temperature and / or approximately (±0.2) ± 1°C / minute to ± 2.5°C / minute for seat temperature. These temperature change rates may apply in environments outside and / or inside the vehicle with an air temperature of approximately 20°C to 25°C. In environments with an air temperature below 20°C, the temperature change rate for skin temperature may be up to ± 1.8°C / minute. In environments with an air temperature below 20°C, the temperature change rate for seat temperature may be up to approximately ± 5°C / minute.

[0086] The present disclosure contemplates that a particular magnitude and / or rate of change in skin temperature may be targeted to provide the desired thermal sensation to the vehicle occupant. That is, the present method aims to provide thermal contrast therapy that can be perceived by vehicle occupants while simultaneously providing comfort to the vehicle occupants. While unpleasant thermal contrast therapy may relieve pain, it may deter occupants from using a vehicle's thermal therapy feature, causing discomfort. For example, a relatively rapid rate of change may be painful to an occupant, while a relatively slow rate of change may not be perceived by an occupant.

[0087] The sensation of heat (ie comfort) depends not only on the temperature of a surface with which the skin comes into contact, but above all on the rate of temperature change of the skin.

[0088] The present method may be controlled and / or evaluated based on the temperature of a heating device, a cooling device, and / or a seating surface, but ultimately these temperatures may be related to how they affect the magnitude of temperature change and / or the rate of change of the occupants' skin.

[0089] The heating device and the cooling device can effect temperature changes in at least one portion of the seat surface. The at least one region can comprise a lower region, a middle region, an upper region, or any combination thereof. Preferably, the at least one region comprises the lower region and optionally the middle region, where back pain often occurs and where pressure on vehicle seats is typically concentrated.

[0090] During the multiple time intervals, a heating device located in a lower portion of a vehicle seat may be heated to a target temperature of approximately 60°C or more, 63°C or more, or even 65°C or more. A heating device located in a lower portion of a vehicle seat may be heated to a target temperature of approximately 71°C or less, 69°C or less, or even 67°C or less.

[0091] During the multiple time intervals, a heating device located in a central region of a vehicle seat may be brought to a target temperature of approximately 74°C or more, 77°C or more, or even 80°C or more. A heating device located in the central region of a vehicle seat may be brought to a target temperature of approximately 89°C or less, 86°C or less, or even 83°C or less.

[0092] During the multiple time intervals, a heating device located in an upper portion of a vehicle seat may be brought to a target temperature of approximately 64°C or more, 67°C or more, or even 70°C or more. A heating device located in the upper portion of a vehicle seat may be brought to a target temperature of approximately 79°C or less, 76°C or less, or even 73°C or less.

[0093] The target temperature of the lower and middle zones compared to the upper zones can be based on the typical pressure exerted by occupants on these zones and / or where back pain typically occurs. Typically, higher pressures are exerted in the lower and middle zones than in the upper zones.

[0094] During the multiple time intervals, the cooling device can be brought to a target temperature of approximately 16°C or more, 18°C ​​or more, or even 20°C or more. During the multiple time intervals, the cooling device can be brought to a target temperature of approximately 26°C or less, 24°C or less, or even 22°C or less.

[0095] During the multiple time intervals, the heating device can be operated by controlling the power supplied to it. The power can be controlled by pulse width modulation (PWM), constant current control, or the like. The heating device can be operated with a duty cycle of approximately 50% or more, 55% or more, or even 60% or more. The heating device can have a duty cycle of approximately 75% or less, 70% or less, or even 65% or less. The cooling device can be equipped with a duty cycle of approximately 75% or more, 80% or more, or even 85% or more. The cooling device can be equipped with a duty cycle of approximately 100% or less, 95% or less, or even 90% or less.

[0096] The method may be time-, temperature-, or time- and temperature-controlled. Operation of one or more heating and / or cooling devices may begin and end when a predetermined time and / or a predetermined temperature is reached. Operation of one or more heating and / or cooling devices may be terminated by occupant input (e.g., by changing a temperature and / or airflow setting).

[0097] The method may be controlled based on sensor feedback. The sensor feedback may provide the temperature of one or more heating and / or cooling devices. Each section of a heating device may include a temperature sensor. That is, various independently controllable resistive element circuits may each include a sensor. The sensor feedback may provide the temperature of a seating surface and / or an occupant's skin. The sensor may include a negative temperature coefficient resistor (NTC), a resistance temperature detector (RTD), a thermocouple, a semiconductor sensor, or any combination thereof.

[0098] The method can be controlled based on a dynamically estimated seat surface temperature and / or skin temperature. That is, the heating and / or cooling device can be operated while the seat surface temperature and / or skin temperature is / are dynamically estimated until time and / or temperature targets specified by the therapy described herein are met or a threshold temperature (e.g., burn or pain threshold) is reached. Dynamic estimates can occur cyclically (e.g., approximately every 1 second or less, 50 milliseconds or less, 30 milliseconds or less, or even 10 milliseconds or less), and each dynamically estimated temperature can be compared to the heat therapy targets and / or threshold temperatures.

[0099] The heating and / or cooling device can be operated in accordance with the time and / or temperature targets of the heat therapy, predetermined thresholds for surface and / or skin temperature change, an error between the dynamically estimated temperature and the heat therapy targets, or any combination thereof. That is, the temperature to which the heating and / or cooling device operates (e.g., via pulse-width modulation, constant current control, and the like) can be determined based on one or any combination of the aforementioned factors.

[0100] Dynamic estimation, as referred to herein, may mean the approximation of a temperature of an element based ultimately on a sensor input remote from the element. In one example, the element may include a surface, an airflow, or an occupant's skin, and the sensor input may indicate the temperature of the cabin air, the temperature of a heating device, the temperature of a cooling device, or any combination thereof. It should also be noted that the sensors discussed herein are not suitable for directly or indirectly measuring the temperature of an occupant or surface, although such sensors may be employed in the thermal therapy described herein.

[0101] In this context, the concept of heat transfer rates can be used. The heat transfer rates between two thermally communicating elements can initially be determined based on one or more sensor inputs. The present disclosure contemplates that, in cases where heat is transferred through multiple elements (e.g., two or more, three or more, or even four or more layers), the heat transfer rates can be determined sequentially by propagating through each of the elements until, ultimately, the temperature of a surface, an air stream, or an occupant's skin is dynamically estimated. The present disclosure also contemplates that, in cases where heat is transferred simultaneously from multiple elements to one element, the sum of the heat transfer rates to the one element (e.g., a surface, an air stream, or an occupant's skin) can be considered by the present method.

[0102] In one example, vehicle seats may be comprised of multiple material layers, including a spacer layer disposed between a heating / cooling device and a trim layer having a surface upon which an occupant is positioned. This arrangement is merely exemplary and not intended to be limiting.

[0103] In another example, vehicle seat occupants may be thermally connected to one or more portions of the seat (e.g., a seat, backrest, bolsters, etc.), the cabin air, one or more radiant heat sources, or any combination thereof. Furthermore, surfaces of the seat may be thermally connected to an underlying material layer that is ultimately thermally affected by a heating and / or cooling device, the cabin air, one or more radiant heat sources, or any combination thereof.

[0104] In another example, HVAC systems may include one or more heat exchangers that may be thermally connected to heating and / or cooling devices, air ducts, air streams, or any combination thereof. Thus, heat may be transferred between a heating and / or cooling device and an air stream through one or more heat exchangers.

[0105] In another example, an air stream may thermally penetrate a duct on its way from a fan to a vent.

[0106] These provisions are also intended to be exemplary only and not restrictive.

[0107] Back to the dynamic estimation. The heat transfer rates (Q̇) can be calculated based on the temperatures of two thermally communicating elements (T1,T2), the surface through which heat is transferred (A surf), and the thermal resistance (R) of the thermally communicating media. The above can be represented by Equation A below. Q˙=(T2−T1)×AsurfR

[0108] The temperatures of the elements can be determined by a sensor input. A sensor can monitor the temperature of a heating / cooling device. A sensor can determine the cabin air temperature. If the temperature of an element that is not directly / indirectly monitored by a sensor is required, the interior air temperature or the dynamically estimated temperature from an immediately preceding program cycle can be used. In the first case, it can be assumed that all elements discussed here were saturated with the measured interior air temperature when the vehicle was started up.

[0109] The surface area and thermal resistance may be predetermined values ​​based on the vehicle design and geometry. These values ​​can be looked up for each pair of media considered in determining the heat transfer rate.

[0110] The temperature of an element (T) can be dynamically adjusted based on the previous temperature of the element (T n-1 ), one or more heat transfer rates associated with the element (∑ Q̇), the thermal capacity (C) associated with the elements, and the program cycle time (Δt) of the method described herein. The above can be represented by Equation B below. T=Tn−1+∑Q˙C×Δt

[0111] As mentioned above, the previous temperature of an element can be observed by a sensor, obtained from a previous program cycle, or assumed to correspond to the cabin air temperature at startup. The thermal capacity and cycle time can be predetermined values. The thermal capacity can be based on the vehicle design and determined based on the element whose temperature is being determined. The cycle time can be based on a timer or clock.

[0112] The one or more heat transfer rates may include the values ​​associated with an element. For example, a spacer layer within a seat may thermally communicate with a heating and / or cooling device and a trim layer of the seat. As another example, a surface of a seat may thermally communicate with a material layer, the cabin air, one or more radiant heat sources, or any combination thereof. As another example, an occupant may thermally communicate with the cabin air, one or more thermally conditioned air streams, a seat surface, one or more radiant heat sources, or any combination thereof. As another example, a heat exchanger may thermally communicate with a heating and / or cooling device, a duct, and an air stream.Another example is that an air stream may be thermally connected to a duct through which it flows and one or more heat exchangers. The above statements are merely exemplary and not intended to be limiting.

[0113] Ultimately, the method described above can be used to dynamically estimate the temperature of a surface, an airflow, and / or an occupant's skin. Thus, if the temperature of an element is determined according to Equation B, and that element is located between two other elements, the temperature determined by Equation B can be used to determine a heat transfer rate with respect to the next element, and the process embodied by Equation A and Equation B can be repeated sequentially until the temperature of a surface, an airflow, and / or an occupant's skin is finally determined.

[0114] This allows target temperatures and / or thresholds for heat therapy (e.g., burn or pain thresholds) to be compared with the dynamic estimates to control heat therapy.

[0115] Estimation is the calculation of a parameter with the knowledge that the result of this calculation may not exactly correspond to the actual value (e.g., the temperature of a surface). Therefore, the result of such a calculation may be an estimate of the actual value. The method of the present disclosure may provide an estimate that deviates from the actual value by 10% or less, preferably by 5% or less, or even preferably by 1% or less.

[0116] Each calculation, determination, dynamic estimation, storage, transmission, and / or retrieval step mentioned herein may be performed by one or more control units. The one or more control units may store predetermined values ​​as described above (e.g., in the form of lookup tables). Any dynamic estimates from previous program cycles may be stored by the one or more control units and / or updated / replaced by dynamic estimates from a current program cycle. Example.Summary.

[0117] A human trial was conducted using heat contrast therapy according to the present teaching. During the trial, the temperature of the seat surface and the participants' skin were monitored, and participants were asked about their subjective local heat sensation, subjective heat comfort, and subjective pain level. The human trial showed that heat contrast therapy provided clinically significant benefits to participants. Device.

[0118] A vehicle seat 10 was designed according to the schematic representation in Fig. 1. The vehicle seat 10 consists of a lower part 12, a middle part 14, an upper part 16, and two side bolsters 18. A heating device 20 is arranged beneath the surface of the vehicle seat 10, comprising a first zone 22, a second zone 24, and a third zone 26. The first zone 22 has a surface power density of 2,407 W / m 2, the second zone 24 has a surface power density of about 2,142 W / m 2 and the third zone 26 has a surface power density of about 1,101 W / m 2 The vehicle seat 10 includes a cooling device 28 located in the center portion 15 of the vehicle seat 10 and within the boundaries of the second zone 24 of the heating device 20. Eight temperature measuring sensors 30 are mounted at various locations on the surface of the vehicle seat 10.

[0119] Participants' skin temperature was measured at nine locations on their backs in a grid of approximately 3x3. One sensor was located above the spine at the lumbar vertebral segment, the lower thoracic vertebral segment (in the region of the T7-T12 vertebrae), and the upper thoracic vertebral segment (in the region of the T1-T6 vertebrae). In addition, two additional sensors were located near each vertebral segment on either side of the spinal sensors.

[0120] During the experiment, participants reported their subjective local heat sensation across their entire back (rated on 9 sensation levels from very hot (level 4) to very cold (level -4)), their subjective local heat comfort across their entire back (rated on 8 comfort levels from extremely comfortable (level 4) to extremely uncomfortable (level -4)), and their subjective pain sensation across their entire back (rated on 11 pain levels from no pain (level 0) to the worst imaginable pain (level 10)). In addition, participants could choose between warm, neutral, or cold settings at each of the 9 locations on their back. After the experiment, participants reported their subjective pain over a period of 2 hours to determine the extent to which the heat therapy continued to have an effect after treatment.

[0121] Regarding subjective pain levels, Chou et al., Nonpharmacologic Therapies for Low Back Pain: A Systematic Review for an American College of Physicians Clinical Practice Guideline, Ann. Int. Med. (2017) offers guidelines for classifying changes in pain severity on a scale of 0 to 10. Any change in pain severity below 0.5 is associated with no effect, any change in pain severity from 0.5 to 0.9 is associated with a small effect, any change in pain severity from 1 to 2 is associated with a moderate effect (considered clinically significant), and any change in pain severity above 2 is associated with a large effect (also considered clinically significant). Chou notes that most medications (e.g., anti-inflammatories, relaxants, opioids, etc.) commonly prescribed for low back pain have only small to moderate and short-term effects. Participant.

[0122] The experiment was conducted with 15 participants aged 20 to 70 (average age 45), of whom 9 were female and 6 were male. The participants wore clothing with a thermal insulation value between 0.29 and 0.45 Clo (1 Clo = 0.155 m 2 C / W) (average 0.38 Clo). Before the study, 5 participants reported chronic back pain (i.e., lasting more than 12 weeks), 5 participants reported subacute back pain (i.e., lasting for 4 to 12 weeks), and 5 participants reported acute back pain (i.e., lasting less than 4 weeks). Methodology.

[0123] In a control experiment, participants remained seated for 38 minutes without the heating or cooling device being activated.

[0124] In the experimental study, participants were seated and preconditioned for 5 minutes without either the heating or cooling device operating. The seated participants then underwent 33 minutes of thermal contrast therapy. During thermal contrast therapy, the first zone of the heating device in the lower part of the seat was set to a target temperature of 65°C, the second zone of the heating device in the middle part of the seat was set to a target temperature of 80°C, and the third zone of the heating device in the upper part of the seat was set to a target temperature of 70°C. The time to reach the target temperature was 1 minute, and the target temperature was maintained for 4 minutes. Then, the heating device was stopped. At the time the heating device stopped operating, the cooling device began operating.The cooling device was operated to a target temperature of 18°C. The time to reach the target temperature was 1 minute, and the target temperature was held for 5 minutes. Then, the cooling device stopped operating, and the time interval was repeated for a total of 3 heating and cooling time intervals. The profile of this heating and cooling is referred to here as the ramp and step profile. The target temperature and the duty cycle of the heater and cooler to reach the target temperatures are shown in the . Fig. shown. Results.

[0125] In the control experiment, the skin temperature of the participants and the temperature of the seat surface were monitored and are shown in the Fig.shown (expressed as the average across all participants). Participants' skin temperature increased by approximately 1.5°C on average due to heat transfer between participant and seat by conduction, and the seat surface temperature remained approximately 2°C below skin temperature on average. Thermal sensation remained neutral (Level 0) on average throughout the experiment; thermal comfort remained slightly comfortable (Level 1) on average throughout the experiment; and average subjective pain did not change on average, measured from immediately before the experiment until the end of the two-hour post-experiment period.

[0126] During the experiment, the skin temperature and seat surface temperature of the participants were monitored and are recorded in Fig. 3C-3D (expressed as an average of all participants). In accordance with the Fig.At the target temperatures of the heating and cooling devices shown in Figure 3A, the participant's skin temperature and the seat surface temperature rise to a sharp peak during heating and fall to a sharp valley during cooling. Skin temperature fluctuated by an average of approximately ± 3.5°C in the lower and mid-back region. The small fluctuation in the upper back region can be attributed to the participant's lack of contact and / or pressure against the seat surface. The seat surface temperature fluctuated by an average of approximately ± 10-20°C.

[0127] The rates of temperature change of the participants' skin and the seat surface at each of the time intervals (expressed as an average across all participants) are shown in Table 1 below. Table 1. Rate of change (°C / min) HeatingEvent1 CoolingEvent1 HeatingEvent2 CoolingEvent2 HeatingEvent3 CoolingEvent3 skin 0.93 -0.62 0.66 -0.52 0.57 -0.49 seat 2.4 -1.5 1.4 -1.2 1.2 -1.0

[0128] In the experiment, the seat surface temperature exceeded 43°C for an average of 160 seconds during event 1, 180 seconds during event 2, and 120 seconds during event 3. A temperature of 43°C is generally considered the threshold at which occupants experience pain. While the seat surface temperature is above this pain threshold, the time it takes to exceed the pain threshold, the rate of temperature change, and the thermal insulation of the participants' clothing preclude a pain response.

[0129] In the experimental study, the average thermal sensation fluctuated between hot (level 3) and cold (level -3) throughout the study period; the average thermal comfort fluctuated between comfortable (level 2) during hot events and slightly comfortable (level 1) during cold events throughout the study period; and the average subjective pain decreased by 1.5 (i.e., moderate effect) measured from immediately before the study to the end of the two-hour period beginning after the study, with the decrease in subjective pain being greatest during the first 25 minutes of thermal contrast therapy. 60% of participants reported a reduction in pain. The subjective pain measured before and after the study for the control study are in Fig. The subjective pain measured before and after the experimental trial is shown in Fig.The dashed lines represent the information provided by individual participants, while the solid line represents the average of all reporting participants.

[0130] Fig.5 shows a thermally regulated surface 30. The surface 30 is a trim layer in a vehicle seat 34, although any surface in the cabin of a vehicle may be contemplated for the method of the present disclosure. The surface 32 is thermally regulated by a heating device 36 (e.g., a resistive heating mat). Heat generated by the heating device is ultimately transferred to the surface 32. As shown, a layer of material 38 (e.g., a spacer layer) is disposed between the heating device 36 and the surface 32. The present teachings contemplate that more than one layer of material 38 may be disposed therebetween, but also that no layer of material 38 may be disposed therebetween. An occupant 40 is located on the surface 32, and the cabin air 42 is in thermal communication with the surface.The control of the heater 36 is ultimately determined by the heat transfer rates in the system, which are indicated by the arrows running between the elements.

[0131] Fig.6 shows a thermally regulated airflow 44. As shown, the airflow 44 is expelled from a seat 46, although any airflow 44 exiting a vent in the vehicle cabin may be considered for the method of the present disclosure. The airflow 44 is thermally regulated by a heating and / or cooling device 48 (e.g., a thermoelectric device). The heat generated by the heating and / or cooling device 48 is ultimately transferred to the airflow 44. As shown, the heating and / or cooling device 48 and the airflow 44 are in thermal communication with a heat exchanger 50, although the present teachings contemplate that no heat exchanger 50 may be present. The airflow 44 flows through a conduit 52 from a fan from which it originates to a vent from which it is expelled.The control of the heating and / or cooling device 48 is ultimately determined by the heat transfer rates in the system, which are indicated by the arrows running between the elements.

[0132] Fig. Figure 7 shows a thermally regulated airflow 54 and a surface 56. The airflow 54 is thermally regulated and passed to a containment device 58. The containment device 58 then thermally regulates the surface 56. The containment device 58 functions similarly to the Fig. 5, although it can also heat and / or cool.

[0133] Here too, heat transfer rates between the aforementioned elements as well as a heating and / or cooling device 60, a heat exchanger 62, a line 64, a material layer 66, an occupant 68 and the cabin air 70 can be determined in a similar manner as described above and in Fig. 7 can be realized.

[0134] The explanations and illustrations contained herein are intended to familiarize those skilled in the art with the invention, its principles, and its practical application. The above description is intended to be illustrative and not restrictive. Those skilled in the art may adapt and apply the invention in its numerous forms as best suited to the needs of a particular application. Other combinations are also possible, as will be apparent from the following claims, which are also hereby incorporated by reference into this written description.

[0135] Accordingly, the specific embodiments of the present invention illustrated are not intended to be exhaustive or limiting. The scope of the teachings should therefore be determined not by reference to this specification, but by reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The omission of any aspect of any subject matter disclosed herein from the following claims is not a waiver of such subject matter, nor should it be construed that the inventors did not consider such subject matter to be part of the disclosed inventive subject matter.

[0136] The information in all articles and references, including patent applications and publications, is incorporated by reference for all purposes.

[0137] Multiple elements or steps can be provided by a single integrated element or step. Alternatively, a single element or step can be divided into multiple separate elements or steps.

[0138] The use of “a” or “an” to describe an element or step is not intended to exclude other elements or steps.

[0139] Although the terms "first," "second," "third," etc., may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used to distinguish one element, component, region, layer, and / or section from another element, component, region, layer, and / or section. Terms such as "first," "second," and other numerical terms do not imply order unless clearly indicated by the context.Thus, a first element, a first component, a first region, a first layer and / or a first section discussed below may also be referred to as a second element, a second component, a second region, a second layer and / or a second section without departing from the teaching.

[0140] The use of "about" or "approximately" in connection with a range applies to both ends of the range. For example, "about 20 to 30" is intended to cover "about 20 to about 30," including at least the specified endpoints.

[0141] Unless otherwise noted, all numerical values ​​mentioned herein include both endpoints and all values ​​from the lower value to the upper value in increments of one unit, provided that there is a separation of at least 2 units between each lower value and each higher value. For example, when the amount of a component, property, or value of a process variable, such as temperature, time, and the like, is stated to be, for example, 1 to 90, 20 to 80, or 30 to 70, it is intended that intermediate values ​​such as (e.g., 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc.) are included within the teachings of this specification. Likewise, individual intermediate values ​​are included in the present description. For values ​​less than one, a unit is considered to be 0.0001, 0.001, 0.01, or 0.1.These are only examples of what is expressly intended, and all possible combinations of numerical values ​​between the lowest and highest enumerated values ​​are to be considered as expressly stated in this application in a similar manner.

[0142] The terms "generally" or "approximately" used to describe numbers or ranges of numbers may mean ± 0.2 for numbers from 0.1 to 1, ± 2 for numbers from 2 to 100, and ± 20 for numbers above 100. The foregoing applies to all percentages, temperatures, times, surface energy densities, or other values ​​unless otherwise specified herein.

[0143] The term "consisting essentially of" to describe a combination includes the recited elements, components, or steps, as well as additional elements, components, or steps that do not substantially affect the basic and novel features of the combination. The use of the terms "consisting of" or "including" to describe combinations of elements, components, or steps also includes embodiments that consist essentially of those elements, components, or steps. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 17 / 957,871

[0001] US 63 / 537,083

[0001] US 9.315.133 B2

[0052] WO 2008 / 115831 A1

[0062] US 9.121.414 B2

[0062] US 9,857,107 B2

[0070] Zitierte Nicht-Patentliteratur

[0000] Carter et al., Sensory and sympathetic nerve contributions to the cutaneous vasodilator response from a noxious heat stimulus, Exp. Physiol. 96.11:1208-1217

[0078]

Claims

[1] A method of providing thermal contrast therapy to a vehicle occupant, the method comprising: first, operating a heating device to apply a first temperature for a first period of time to bring a temperature of at least one portion of a seat surface to about 43°C to 48°C and / or a skin temperature of the vehicle occupant in an area of ​​the at least one portion to about 36°C or more; and second, operating the heating device and a cooling device alternately for a plurality of time intervals, wherein during the plurality of time intervals the heating device is operated for a second period of time and the cooling device is operated for a third period of time; wherein the thermal contrast therapy causes a change in the temperature of the at least one portion of the seat surface of approximately 10°C to 20°C and / or a change in the skin temperature of the vehicle occupant in the region of the at least one portion of the seat surface of approximately 3°C to 6°C. [2] The method of claim 1, wherein the heating device and the cooling device cause temperature changes in the at least one portion of the seating surface during the plurality of time intervals, the at least one portion comprising a lower portion, a middle portion, an upper portion, or any combination thereof. [3] The method of claim 1 or claim 2, wherein the heater is located in the lower and middle sections, and during the plurality of time intervals, the heater in the lower section is brought to a target temperature of about 63°C to 67°C and the heater in the middle section is brought to a target temperature of about 77°C to 83°C. [4] The method according to any one of the preceding claims, wherein the heating device is located in the upper section and during the plurality of time intervals the heating device in the upper section is brought to a target temperature of about 70°C. [5] The method according to any one of the preceding claims, wherein the cooling device is brought to a target temperature of about 18°C ​​to 22°C during the plurality of time intervals. [6] The method according to any one of the preceding claims, wherein during the plurality of time intervals the heating device is operated by pulse width modulation with a duty cycle of about 55% to 65% and the cooling device is operated by pulse width modulation with a duty cycle of about 85% to 95%. [7] The method according to any one of the preceding claims, wherein the operating time of the heating means and the cooling means is the same during the plurality of time intervals. [8] The method according to any one of the preceding claims, wherein the rate of temperature change during the plurality of time intervals is ± 0.4°C / minute to ± 0.9°C / minute for skin temperature and / or ± 1°C / minute to ± 2.5°C / minute for seat temperature. [9] The method of any preceding claim, wherein the plurality of time intervals last for a duration of about 20 to 35 minutes. [10] The method according to any one of the preceding claims, wherein the alternating heating and cooling are each characterized by a ramp and step profile, the ramp and step profile of heating being inverse to the ramp and step profile of cooling. [11] The method according to any one of the preceding claims, wherein there is no idle time between the alternating operation of the heating device and the cooling device; wherein the idle time is characterized by a period in which both the heating device and the cooling device are not in operation. [12] The method according to any one of the preceding claims, wherein the time intervals comprise 6 to 16 time intervals. [13] The method according to any one of the preceding claims, wherein the second time period is 3 to 5 minutes and wherein the third time period is 3 to 6 minutes. [14] The method according to any one of the preceding claims, wherein the heating device is operated by pulse width modulation with a duty cycle of about 55% to 65% to realize the first temperature. [15] The method according to any one of the preceding claims, wherein the first temperature is about 55°C to 90°C. [16] The method according to any one of the preceding claims, wherein the first period of time is about 5 to 10 minutes. [17] The method according to any one of the preceding claims, wherein the thermal contrast therapy is directed to alleviate pain of the vehicle occupant. [18] An apparatus for performing the method according to claim 1, the apparatus comprising: a heating device arranged in an upper portion of the seat, a middle portion of the seat and a lower portion of the seat; and a cooling device acting on the middle portion of the seat. [19] The device of claim 18, wherein the heating device comprises a resistive element; and the cooling device comprises a fan, a thermoelectric device, a fluid distribution device, or any combination thereof; wherein the heating device in the lower portion has a surface power density of about 2,100 W / m 2 up to 2,500 W / m 2 the heating device in the middle section has a surface power density of about 1,900 W / m 2 up to 2,300 W / m 2 and the heating device in the upper section has a surface power density of about 900 W / m 2 up to 1,500 W / m 2 has. [20] A vehicle seat comprising the device according to claim 18 or claim 19. [21] The method according to any one of claims 1 to 17, wherein the temperature of the at least one portion of the seat surface and / or the skin temperature of the vehicle occupant is determined by a dynamic estimation taking into account one or more heat transfer rates relative to the at least one portion of the seat surface and / or the skin temperature of the vehicle occupant.

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