JP2013258055A - Heating device for vehicle seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating device for a vehicle seat capable of raising temperature fast and slowing down the temperature rising at a predetermined temperature to prevent overheating, thus realizing a stable temperature control, of maintaining a warm state for a while after power-off, and of reducing a used power amount.SOLUTION: A heat storage body 21 is arranged on a surface of a cushion pad 61 for a vehicle seat. A planar heating element 11 configured by arranging a plurality of carbon fiber bundles 15 between insulation sheets 13 in parallel and in a planar shape so as not to intersect each other, and connecting electrode conductors to both edges in a longitudinal direction of the carbon fiber bundles 15, is arranged on the heat storage body 21. Thus, the planar heating element 11 and the heat storage body 21 configure a heating device 10 for a seat. The surface of the cushion pad 61 for a seat together with the heating device 10 for a seat is covered with a skin 71.

Description

  The present invention relates to a heating device for a seat of a vehicle.

In recent years, a heating wire heater is disposed on a vehicle seat to heat the seat (Patent Document 1). The heating wire heater arranged in the seat has a heating wire that becomes a constant temperature (for example, about 40 ° C.) when energized. By continuously supplying power to the heating wire, the seating surface and the backrest surface of the seat can be warmed. it can.
Further, as a planar heating element, one in which carbon fiber bundles are arranged in parallel and electrodes are provided on both edges has been proposed (Patent Document 2).

However, the heating wire heater has a problem that it takes time to raise the temperature to a certain temperature (for example, 40 ° C.) and a problem that a large amount of power is consumed to maintain the temperature.
On the other hand, a sheet heating element using a carbon fiber bundle has a higher heating rate than a heating wire heater, but also has a higher heat dissipation, so when it is set to a resistance value that can be maintained at a constant temperature, the power consumption becomes large. There is. Furthermore, if the temperature of the planar heating element is adjusted by turning on / off the power supplied to the carbon fiber bundle, the temperature is not stabilized because the temperature rises and falls quickly, and overheating may occur.

  Also, in both the heating element heater and the planar heating element using carbon fiber bundles, in cold areas, if the power is turned off, the seat will quickly cool down. The seat cools just by leaving and sits in the cold seat when returning to the car.

JP 2003-347016 A JP 2001-237052 A

  The present invention has been made in view of the above-described points, and the temperature rises quickly, and the temperature rise becomes moderate at a predetermined temperature so that overheating does not occur, and stable temperature control is possible. It is an object of the present invention to provide a vehicle seat heating device that can maintain a warm state during the period and can reduce the amount of power used.

  According to a first aspect of the present invention, in the vehicle seat heating device installed on the vehicle seat cushion pad, the plurality of carbon fiber bundles are arranged in parallel and in a plane shape so as not to cross between the insulating sheets. It consists of a planar heating element in which electrode conductors are connected to both edges in the longitudinal direction of the carbon fiber bundle, and a thermal storage element arranged on the back surface opposite to the passenger side of the planar heating element, the thermal storage element is A heat storage material having a melting point of 35 ° C. to 45 ° C. is accommodated in a bag body, and the heat storage body is not disposed on the passenger side surface of the planar heating element.

  According to a second aspect of the present invention, in the first aspect, the power supply to the carbon fiber bundle is performed by a power supply device connected to the electrode conductor, and the power supply to the carbon fiber bundle is performed by the power supply device. Is controlled by a temperature control device, and when the temperature of the heat storage body reaches an upper limit set temperature equal to or higher than the melting point of the heat storage material, power supply to the carbon fiber bundle is stopped, and the temperature of the heat storage body is The power supply to the carbon fiber bundle is resumed when the lower limit set temperature lower than the melting point of the material is reached.

  According to the first aspect of the present invention, a plurality of carbon fiber bundles are arranged in parallel so as not to intersect between the insulating sheets, and electrode conductors are connected to both edges in the longitudinal direction of the carbon fiber bundles. Because the sheet heating element is used, the temperature rises quickly, and no heat storage element is disposed on the passenger side surface of the sheet heating element. The seat surface can be warmed.

  In addition, since the heat storage body is arranged on the back surface opposite to the passenger side of the sheet heating element, the heat storage body stores heat while power is supplied to the sheet heating element. However, the seat surface can be kept warm by the heat stored in the heat storage body for a while. Furthermore, since the heat storage material contains a heat storage material having a melting point of 35 ° C. to 45 ° C. close to the body temperature, when the heat storage material is heated to the melting point by the planar heating element, The temperature rise is suppressed, the temperature rises gradually, overheating is suppressed, and the temperature can be controlled near the body temperature.

  In addition, as described above, the temperature of the seat rises quickly, and the seat surface is warm for a while after the power is turned off, so when you turn off the vehicle and leave the vehicle for a short period of shopping, when you return to the vehicle, Is not completely cold and does not feel cold. Moreover, since the vehicle seat heating device is not completely cooled down by the heat stored in the heat storage body, when the power is turned on again, the temperature of the seat surface can be raised in a short time, The amount of power used can be reduced.

  According to the invention of claim 2, when the temperature of the heat storage body reaches an upper limit set temperature equal to or higher than the melting point of the heat storage material, power supply to the carbon fiber bundle is stopped, and the temperature of the heat storage body is changed to the heat storage body. When the lower limit set temperature lower than the melting point of the material is reached, power supply to the carbon fiber bundle is resumed, so that overheating can be suppressed and the power consumption can be further reduced.

It is a schematic sectional drawing which shows the use condition of the heat generating apparatus for seats of the vehicle which concerns on one Embodiment of this invention. 1 is a perspective view showing a sheet heating element and a heat storage element of a vehicle seat heating device according to an embodiment of the present invention. 1 is an exploded perspective view of a sheet heating element of a vehicle seat heating device according to an embodiment of the present invention. It is a graph which shows the surface temperature change of a seat.

  As shown in FIG. 1, a vehicle seat heating device (hereinafter referred to as a seat heating device) 10 according to an embodiment of the present invention is installed between a vehicle seat cushion pad 61 upper surface and a skin 71 lower surface. used. The vehicle seat is composed of a seat portion 51 and a backrest portion 55, and is composed of a seat cushion pad 61 and a skin 71, respectively. In the present embodiment, the seat heating device 10 is installed in both the seat 51 and the backrest 55, but the seat heating device 10 is installed only in either the seat 51 or the backrest 55. May be.

The seat cushion pad 61 is made of foam such as urethane foam. The surface of the cushion pad 61 for the seat is provided with a recess 63 for accommodating the seat heating device 10, and the seat heating device 10 is disposed in the recess 63 so that the seat heating device 10 protrudes toward the passenger side. It is preferable to prevent such a feeling of incongruity.
The skin 71 is made of fabric, leather, synthetic leather, or the like, covers the surfaces of the seat cushion pad 61 and the seat heating device 10, and forms the surfaces of the seat 51 and the backrest 55.

  The seat heating device 10 includes a planar heating element 11 and a heat storage body 21 disposed on the back surface opposite to the occupant side of the planar heating element 11. The heat storage body 21 is not disposed between the skin 71 and the planar heating element 11.

  As shown in the perspective view of FIG. 2 and the exploded perspective view of FIG. 3, the planar heating element 11 is arranged in a planar manner in parallel between the insulating sheets 13 and 13 so that the plurality of carbon fiber bundles 15 do not intersect. The electrode conductors 17 and 17 are connected to both edges in the longitudinal direction L of the carbon fiber bundle 15.

  The insulating sheets 13 and 13 are preferably resin sheets having insulating properties, and more preferably resin sheets having insulating properties and heat resistance. Examples of the insulating sheet include a thickness of 0.01 to 1 mm, a polyethylene terephthalate resin (PET resin), or a polypropylene resin (PP resin). The insulating sheets 13 and 13 are laminated (bonded) by bonding or the like with the plurality of carbon fiber bundles 15 and the electrode conductors 17 and 17 interposed therebetween.

The carbon fiber bundle 15 is not particularly limited as the type of carbon fiber. For example, a polyacrylonitrile-based carbon fiber (PAN-based carbon fiber) obtained by firing polyacrylonitrile fiber, or a pitch-based carbon fiber formed using a pitch. Any of these may be used. Moreover, although the number of carbon fibers is made into an appropriate number, 1000-60000 can be mentioned as an example.
The electrode conductors 17 and 17 are composed of a metal tape made of metal foil or the like, or a conductive wire such as a metal wire. The positions of the plurality of carbon fiber bundles 15 and electrode conductors 17 and 17 are fixed by joining the insulating sheets 13 and 13. A lead wire 19 made of a conductive wire such as a metal wire is connected to the electrode conductors 17, 17 and extends outside the insulating sheets 13, 13.

In the heat storage body 21, a heat storage material is accommodated in a bag body 22, and the bag body 22 is sealed. The bag body 22 is made of an insulating material, and more preferably made of a material having insulating properties and heat resistance. For example, a laminate made of a resin sheet made of polypropylene resin (PP resin) or polyethylene resin (PE resin), or a laminate in which a metal foil such as aluminum is sandwiched between resin films made of PP resin or PE resin. The formed can be mentioned.
The said heat storage material consists of a 35 to 45 degreeC whose melting | fusing point is close to body temperature. Examples thereof include polyethylene glycol (molecular weight 1500, melting point 40 ° C.) and paraffin (melting point 40 ° C.).
The size of the heat storage body 21 is determined according to the size of the planar heating element 11 and the like, and one or a plurality of the thermal storage elements 21 are arranged on the back surface opposite to the passenger side of the planar heating element 11.

  In the seat heating device 10, the lead wire 19 is connected to a temperature control device 31 and a power supply device 35 (for example, a battery of a vehicle), and power is supplied from the power supply device 35 to the carbon fiber of the planar heating element 11. Supplied to the bundle 15. The temperature control device 31 is a device that controls power supply to the carbon fiber bundle 15, that is, a thermostat, and is a temperature detection unit disposed in contact with the heat storage body 21, for example, a thermocouple that detects the heat storage body 21. When the temperature reaches the preset upper limit set temperature, the power supply to the carbon fiber bundle 15 is stopped (OFF), while the temperature of the heat storage body 21 is set in advance. When the power reaches the value, the power supply to the carbon fiber bundle 15 is resumed (ON).

  The upper limit set temperature is set to a predetermined temperature equal to or higher than the melting point of the heat storage material, for example, 0 to 20 ° C., while the lower limit set temperature is a predetermined temperature, for example, 1 to 10 ° C. lower than the melting point of the heat storage material. Set to

  The seat heating device 10 disposed in the vehicle seat is supplied with power from the power supply device (battery) 35 to the carbon fiber bundle 15 of the planar heating element 11, so that the carbon fiber bundle 15 is Heat is generated in a short time (for example, 1 to 2 seconds), and the planar heating element 11 is heated to heat the seat surface. At this time, since the heat storage body 21 does not exist on the passenger side, the seat surface is quickly heated. Further, as the temperature of the sheet heating element 11 is increased, the heat storage body 21 disposed on the back side of the sheet heating element 11 is heated, and heat is stored in the heat storage material accommodated in the heat storage element 21. It is done.

When the sheet heating element 11 reaches the melting point (35 to 45 ° C.) of the heat storage material, the heat storage material is melted and heat is taken away from the back side of the sheet heating element 11 by the latent heat of fusion, and the sheet heat generation is performed. The temperature rise of the body 11 becomes moderate, and overheating is suppressed. When the temperature of the heat storage body 21 further rises after the heat storage material is melted and reaches the upper limit set temperature, the power is cut by the temperature control device 31, and the power supply to the carbon fiber bundle 15 is stopped (OFF). The When the power supply is stopped, the carbon fiber bundle 15 stops generating heat, and instead of the planar heating element 11, the heat storage material that has been storing heat so far dissipates and heats the seat surface. When the temperature of the heat storage material of the heat storage body 21 is lowered to the melting point, the solidification heat is released when the heat storage material is solidified to heat the seat surface, and the temperature decrease of the seat surface is further delayed even when the power is stopped (OFF).
Thereafter, when the temperature of the heat storage body 21 is lowered to the lower limit set temperature, the temperature control device 31 restarts (ON) the power supply to the carbon fiber bundle 15, the carbon fiber bundle 15 generates heat again, and the seat Heating of the surface and heat storage of the heat storage material are performed.

First, the following heat storage body was arranged on the surface of a cushion pad (urethane foam) for a vehicle seat. Next, the following sheet heating element A is placed on the heat storage body, and the seat heating apparatus of Example 1 including the heat storage element and the sheet heating element A is formed, and a temperature detection unit ( The seat heating device of Example 1 was placed between the cushion pad and the skin by covering the seat cushion pad together with the seat heating pad together with the seat heating pad.
-Thermal storage body The thermal storage body used the product number: HAL-400 + 40, the product made by Inoac Corporation. The bag body of the heat storage body is a laminate having an inner layer made of a nylon film, an intermediate layer made of an aluminum film, and an outer layer made of a polyethylene film in a bag shape having dimensions of 200 × 300 × t7.5 mm. The heat storage material accommodated in the bag is 400 g of polyethylene glycol (molecular weight 1500, melting point 40 ° C.).
・ Surface heating element A
On one of two polyethylene terephthalate (PET) films (dimensions 200 × 300 × t0.05 mm), carbon fiber bundles (filament symbol: 24K, manufactured by Toho Tenax Co., Ltd., length 70 cm) are arranged at approximately equal intervals. This is placed parallel to each other so as not to cross each other, electrode conductors made of copper wire are placed on both edges in the longitudinal direction of the carbon fiber bundle, and the other polyethylene terephthalate film is placed on the carbon fiber bundle and laminated. Thus, a planar heating element A was formed.

The length of the carbon fiber bundle in the sheet heating element A of Example 1 is set to 100 cm, and the sheet heating element B is formed in the same manner as in Example 1 except that the sheet heating element B is formed without using a heat storage element. The seat heating device of Comparative Example 1B was formed between the cushion pad and the skin.
Further, instead of the planar heating element B in the comparative example 1B, a 10 m long nichrome wire (resistance value: 9.8Ω) is arranged meandering between the cushion pad and the skin, did. In Comparative Example 2, both ends of the nichrome wire constitute an electrode conductor.

・ Comparison of power consumption A power source of 12 V was applied to both ends of the sheet heating element A of Example 1 and the electrode conductor B of Comparative Example 1B and the nichrome wire of Comparative Example 2 at an ambient temperature of 23 ° C., and the temperature detector By measuring the temperature with a thermocouple, and turning off the power when it reaches 40 ° C (upper limit temperature), while turning on the power when the temperature drops to 35 ° C (lower limit temperature), The power was turned on and off so that the temperature was 35 ° C. to 40 ° C. over 30 minutes. As a result, the total ON time in 30 minutes, that is, the total energization time was 10 minutes in Example 1 (planar heating element A + heat storage element), whereas Comparative Example 1B (planar heating element B only). And in Comparative Example 2 (Nichrome wire only), the temperature immediately became 35 ° C. or less when turned off, so it had to be turned on for 30 minutes.

  Table 1 shows data during seat heating for 30 minutes in Example 1, Comparative Example 1B, and Comparative Example 2. The resistance value (Ω) in Table 1 is the resistance value for each carbon fiber bundle in Example 1 and Comparative Example 1B, and the resistance value of the entire nichrome wire in Comparative Example 2. The current value (A) is a current value during energization, the power (W) is a voltage value × current value, and the amount of heat (1h) (Wh) is a value obtained by converting the value of power × energization time to 1 hour. In addition, calorie | heat amount (1h) (kWh) is the value which converted unit Wh of calorie | heat amount (1h) (Wh) into kWh.

  As shown in Table 1, Example 1 (planar heating element A + heat storage body) has a smaller amount of heat (amount of power) than Comparative Example 1B (planar heating element B only) and Comparative Example 2 (only nichrome wire), It can be seen that a reduction in power consumption can be realized.

-Comparison of surface temperature change Comparative Example 1A (only the planar heating element A) using only the sheet heating element A of Example 1 without using a heat storage element is prepared, and the cushion is the same as in Example 1 etc. It arrange | positions between a pad and an outer_skin | epidermis, Example 1 (planar heating element A + heat storage body), Comparative example 1A (planar heating element A only), Comparative example 1B (planar heating element B only), and Comparative example 2 (Nichrome wire only) A 12V power source at an ambient temperature of 23 ° C., a temperature detection unit (on the skin) where the temperature of the seat surface when the power is turned off after energizing for 10 minutes (600 seconds) ( Thermocouple). FIG. 4 shows the measurement results. Note that the time in FIG. 4 is the elapsed time from the start of energization.

  As shown in FIG. 4, Example 1 (planar heating element A + heat storage element) is similar to Comparative Example 1A (planar heating element A) and Comparative Example 1B (planar heating element B only). It can be seen that the temperature rises more quickly than in Comparative Example 2 using only the nichrome wire, and the seat surface warms in a short time. Further, when Example 1 (planar heating element A + heat storage element) using the same planar heating element A is compared with Comparative Example 1A (planar heating element A only), immediately before the power is turned off (600 seconds have passed since energization). Then, while Example 1 (sheet heating element A + heat storage body) using the heat storage body was about 42 ° C., Comparative Example 1A (only the sheet heating element A) not using the heat storage body was about 71. The temperature was raised to ° C. From the result, it can be seen that in Example 1 (planar heating element A + heat storage element), heat generated by the sheet heating element is stored in the heat storage material of the heat storage element, and overheating is suppressed. On the other hand, a sheet heating element B different from that of Example 1 is used, and Comparative Example 1B (only the sheet heating element B) that does not use a heat storage body is used. Nichrome wire only) was about 41 ° C. just before the power was turned off.

  Further, after the power is turned off, in Example 1 (planar heating element A + heat storage body) that uses a heat storage body together, the temperature drop is gradual, and when 100 seconds have passed since the power supply was turned off (700 seconds have passed since the start of energization). The temperature difference was about 33 ° C. at the time of about 36 ° C. for 500 seconds (1100 seconds after the start of energization), and there was only about 9 ° C. temperature difference immediately before the power was turned off and after 500 seconds had passed since the power was turned off. On the other hand, Comparative Example 1A (only the planar heating element A) not using a heat storage body is about 38 ° C. and 500 seconds have elapsed (from the start of energization) when 100 seconds have elapsed since the power was turned off (700 seconds have elapsed since the start of energization). At about 1100 seconds, the temperature difference was about 25 ° C., and the temperature difference between just before the power was turned off and 500 seconds after the power was turned off was about 46 ° C.

  On the other hand, Comparative Example 1B (only the planar heating element B) using the planar heating element B different from that of Example 1 and not using the heat accumulating member is used when 100 seconds have elapsed since the power was turned off (700 seconds have elapsed since the start of energization). ) And about 23 ° C. when 500 seconds have elapsed (when 1100 seconds have elapsed since the start of energization), and the temperature difference between just before the power was turned off and after 500 seconds had passed since the power was turned off was about 18 ° C. Further, Comparative Example 2 using only nichrome wire and not using a heat storage body (only nichrome wire) is about 28 ° C. and 500 seconds have passed after 100 seconds have elapsed since power was turned off (700 seconds have passed since the start of energization). The temperature difference was about 23 ° C. at the time when 1100 seconds had elapsed from the start, and the temperature difference between just before the power was turned off and 500 seconds after the power was turned off was about 18 ° C.

  From these results, Comparative Example 1A (only the planar heating element 1A) and Comparative Example 1B (only the planar heating element B) and Comparative Example 2 (only the nichrome wire) that do not use the thermal storage body are combined with the thermal storage body. It can be seen that the temperature drop after turning off the power is faster than in Example 1 (planar heating element A + heat storage element). Furthermore, Comparative Example 1B consisting only of the planar heating element B has a faster temperature drop at the time when 100 seconds have elapsed since turning off the power than Comparative Example 2 consisting only of the nichrome wire, and the carbon fiber bundle is after the power is turned off than the nichrome wire. It can be seen that the temperature drops quickly.

  Thus, the embodiment can reduce the amount of power used as shown in Table 1, and the temperature can be raised quickly as shown in FIG. Further, as is clear from the comparison with Comparative Example 1A in FIG. 4, the example suppresses the temperature rise of the planar heating element by the heat storage element, suppresses overheating as the temperature rises gradually, and the temperature near the body temperature. It is possible to control. In addition, the seat surface can be kept warm by the heat stored in the heat storage body for a while after the power is turned off. Even when the power is turned on again for heating, the seat heating unit is not cooled down, so that the amount of power used can be reduced.

DESCRIPTION OF SYMBOLS 10 Seat heating device 11 Planar heating element 13 Insulating sheet 15 Carbon fiber bundle 17 Electrode conductor 21 Heat storage body 31 Temperature control device 35 Power supply device 61 Seat cushion pad 71 Skin

Claims (2)

In a vehicle seat heating device installed on a vehicle seat cushion pad,
A planar heating element in which a plurality of carbon fiber bundles are arranged in parallel so as not to cross between the insulating sheets in parallel and the electrode conductors are connected to both edges in the longitudinal direction of the carbon fiber bundle;
It consists of a heat storage body arranged on the back surface opposite to the passenger side of the planar heating element,
In the heat storage body, a heat storage material having a melting point of 35 ° C. to 45 ° C. is accommodated in a bag body,
The vehicle seat heating device, wherein the heat storage body is not disposed on a passenger-side surface of the planar heating element. Power supply to the carbon fiber bundle is performed by a power supply device connected to the electrode conductor,
Power supply to the carbon fiber bundle by the power supply device is controlled by a temperature control device,
When the temperature of the heat storage body reaches an upper limit set temperature equal to or higher than the melting point of the heat storage material, power supply to the carbon fiber bundle is stopped,
2. The vehicle seat heat generation according to claim 1, wherein when the temperature of the heat storage body reaches a lower limit set temperature lower than the melting point of the heat storage material, power supply to the carbon fiber bundle is resumed. apparatus.

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