JP4228648B2 - Cooling device for vehicle steering wheel - Google Patents

Description

【０１０２】
比較例１（作動流体なし）および比較例２（現行ステアリングホイール）の場合には、反転してから３０秒経過しても、リム上部の温度は、約１０℃しか降下せず、乗員が素手で握ることが可能な温度領域である約６０℃を超える約７０℃であり、加熱されたリム上部の冷却が不十分であった。
【０１０３】
一方、本発明の実施例の場合には、反転してから１０秒経過するだけで、リム上部の温度は、１７．３℃も降下し、乗員が素手で握ることが可能な温度領域である約６０℃近傍にまで冷却され、反転してから３０秒経過すれば、リム上部の温度は、２５．１℃も降下して５３．１℃となり、乗員が素手で握ることが可能な温度領域である約６０℃以下にまで十分に冷却された。
【０１０４】
これにより、ステアリングホイールにおいてリムをヒートパイプとすることにより、炎天下に長時間駐車することにより高温となったリムの高温部を瞬時に冷却することができ、さらに潜熱蓄熱材をヒートパイプ管内に封入することによりステアリングホイールの冷却効果を一層高め得ることが確認できた。
【図面の簡単な説明】
【図１】 図１（Ａ）は、本発明の第１の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールを示す外観図、図１（Ｂ）は、同図（Ａ）の１Ｂ−１Ｂ線に沿う断面図である。
【図２】 本発明の第２の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールの図１（Ｂ）に相当する断面図である。
【図３】 本発明の第３の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールを示す外観図である。
【図４】 本発明の第４の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールの図１（Ｂ）に相当する断面図である。
【図５】 図５（Ａ）は、本発明の第５の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールを示す外観図、図５（Ｂ）は、同図（Ａ）の５Ｂ−５Ｂ線に沿う断面図、図５（Ｃ）は、同図（Ａ）の５Ｃ−５Ｃ線に沿う断面図、図５（Ｄ）は、第５の実施形態の改変例に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールの図５（Ｃ）に相当する断面図である。
【図６】 図６（Ａ）は、本発明の第６の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールを示す外観図、図６（Ｂ）は、同図（Ａ）の６Ｂ−６Ｂ線に沿う断面図である。
【図７】 図７（Ａ）は、本発明の第７の実施形態に係る車両用ステアリングホイールの冷却装置を組み込んだステアリングホイールを示す外観図、図７（Ｂ）は、同図（Ａ）の７Ｂ−７Ｂ線に沿う断面図である。
【図８】 図８（Ａ）は、一般的な車両用ステアリングホイールを示す外観図、図８（Ｂ）は、同図（Ａ）の８Ｂ−８Ｂ線に沿う断面図、図８（Ｃ）は、他のリム芯材を示す断面図である。
【符号の説明】
１１０、１２０、１３０、１４０、１５０、１６０、１７０…車両用ステアリングホイール
１０…リム
１１、１４…リムの芯材
１２…クッション層
１５…リム下部（車輪の向きを直進方向に向ける位置を基準としたときのリムの下部部分）
２０…スポーク
４０、４１、４２、４３…ヒートパイプ
５０、５１…蓄熱体
６０…断熱材[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling device for a steering wheel for a vehicle.
[0002]
[Prior art]
In a hot summer environment, the interior of a parked automobile is very hot, and in particular, the temperature at the top of the steering wheel that is exposed to solar radiation may exceed about 80 ° C. In such a situation, it goes without saying that the passenger feels uncomfortable when he gets on, but there are also inconveniences that the driver cannot start driving immediately and the steering wheel cannot be gripped firmly during driving.
[0003]
In order to solve this type of problem, as a conventional technique for cooling a steering wheel for a vehicle, a technique in which a heat storage material sealed in a resin container is installed in a ring-shaped rim pipe provided in the steering wheel (see, for example, Patent Document 1). ) And a technique for supplying cold heat by installing a Peltier element on the steering wheel (see, for example, Patent Document 2).
[0004]
The technique described in Patent Document 1 is based on the principle that the latent heat of fusion of the heat storage material takes away the solar radiation energy applied to the rim, thereby delaying the temperature rise of the steering wheel.
[0005]
The technique described in Patent Document 2 has a structure in which a Peltier element is installed in a hub portion at the center of a wheel, and the generated cold heat is conducted to a rim through a spoke.
[0006]
[Patent Document 1]
JP 11-259157 A
[Patent Document 2]
Japanese Patent Laid-Open No. 06-249540
[0007]
[Problems to be solved by the invention]
However, since the technique described in Patent Document 1 has a structure in which the heat storage material is fixed in the pipe of the rim, the amount of the heat storage material that can be enclosed is limited. For this reason, it is difficult to obtain the sustainability of the effect of suppressing the temperature rise of the steering wheel.
[0008]
Further, the technique described in Patent Document 2 cannot immediately obtain the effect of cooling the steering wheel even if the Peltier element is operated after the engine is started. Moreover, since the power load of the Peltier element is generally large, there is a concern about troubles due to battery consumption in the summer when the load is high even for the battery.
[0009]
The present invention has been made in view of such a problem of the prior art, and is a temperature at which a high-temperature portion of a rim that has been parked for a long time under hot weather and can be operated without using energy such as electric power can be operated. It is an object of the present invention to provide a cooling device for a steering wheel for a vehicle that can be quickly cooled down to the above.
[0010]
[Means for Solving the Problems]
The object of the present invention is achieved by the following means.
[0011]
The present invention relates to a vehicle steering wheel including a ring-shaped rim, wherein the rim is configured from a heat pipe, and the lower portion of the rim is based on a position where the direction of the wheel is directed in a straight traveling direction. Pass At the same time, the lower part of the rim becomes a low temperature part whose temperature is lower than that of the upper part of the rim during parking, and the heat capacity of the low temperature part becomes a cold heat source. This is a cooling device for a steering wheel for a vehicle.
Further, the present invention provides a vehicle steering wheel including a ring-shaped rim, wherein a heat pipe is disposed along the core material of the rim, and the rim when the wheel is oriented in the straight direction is used as a reference. The heat pipe passes through the lower part At the same time, the lower part of the rim becomes a low temperature part whose temperature is lower than that of the upper part of the rim during parking, and the heat capacity of the low temperature part becomes a cold heat source. This is a cooling device for a steering wheel for a vehicle.
[0012]
【The invention's effect】
According to the present invention, by configuring the rim of the steering wheel from a heat pipe, the high temperature portion of the rim, which has been parked for a long time under the hot sun and becomes high temperature, can be operated without using energy such as electric power. There is an effect that it can be cooled quickly.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The cooling device for a vehicle steering wheel according to the present invention, in brief, in a vehicle steering wheel having a ring-shaped rim, heats the rim by sealing a working fluid under reduced pressure inside a metal tube normally used as a rim. It is characterized by comprising pipes or arranging heat pipes circumferentially along the rim. In order to further enhance the cooling effect of the steering wheel, a cold heat storage body for storing cold heat is provided in the heat pipe so that heat can be transferred, or the lower part of the rim when the wheel is oriented in the straight direction is used as a reference. It is characterized by being covered with a heat insulating material.
[0014]
A heat pipe is known as a heat transport device in which a small amount of liquid called working fluid is sealed in a metal tube and has a heat conductivity several hundred times that of a metal having high heat conductivity such as copper. The operating principle of heat transport is based on the phenomenon that the working fluid sealed with saturated vapor pressure evaporates in the high temperature part and condenses in the low temperature part in the range from the solidification temperature to the critical temperature of the working fluid. The heat transfer theoretically occurs at the speed of sound, which is the limit of the steam transfer speed, and has the function of instantaneously equalizing the temperature in the pipe. When this mechanism occurs continuously between the low-temperature part and the high-temperature part, an ultrafast heat transport function is exhibited.
[0015]
However, in order for the heat transport function to continue, it is necessary to recirculate the working fluid condensed in the low temperature part, that is, the condensing part, to the high temperature part, that is, the evaporation part. When the heat pipe is used in the bottom heat mode in which the high temperature part is placed below and the low temperature part is set up, the condensed working fluid flows down to the high temperature part again by gravity, and the heat transport cycle is continued. On the other hand, when the heat pipe is used in the top heat mode with the high temperature part on top and the low temperature part on the bottom, the reflux of the condensed working fluid to the high temperature part is delayed due to the influence of gravity, and heat transport The function stops working. Many of today's heat pipes have a wick structure formed in the tube, and the condensed working fluid is recirculated by the capillary force of the wick. However, even if the wick is installed, if the heat transport capability is significantly reduced in the top heat mode, and the capillary force of the wick is small or the height difference between the high temperature part and the low temperature part is large, the heat transport function is still necessary. Will not work. Such a point is a characteristic or a defect of the heat pipe, and is treated as common sense in designing a heat dissipation system using the heat pipe.
[0016]
The present invention makes use of the ultra-high-speed heat transport function, which is the original function of the heat pipe, and pays attention to the characteristic or defect that the function stops in the top heat mode, and switches between the operation and stop of the heat transport function. This is a new “switch function”. In other words, the steering wheel has a top heat mode temperature distribution in which the upper part that receives solar radiation becomes a high temperature part and the lower part that is shaded becomes a low temperature part when parked in hot weather, but with the start of operation, The high temperature part and the low temperature part are switched. In light of this point, focusing on the fact that the rotation of the steering wheel exhibits the “switch function”, a novel vehicle steering wheel cooling device according to the present invention has been completed.
[0017]
The present invention will be described in a practical situation.
[0018]
During parking, the upper part of the rim of the steering wheel (hereinafter referred to as “rim upper part”) is heated by solar radiation, but since this state is the top heat mode, the heat transport function does not operate. On the other hand, the lower part of the rim (hereinafter referred to as “rim lower part”) is maintained at about the room temperature. Here, even if the parking state lasts for several hours, the temperature difference between the part that receives solar radiation and the part that does not receive solar radiation is maintained, and the temperature of the low temperature part is usually 50 ° C. or less, and remains at about 60 ° C. at most. The heat capacity of the low temperature portion is a cooling heat source in the present invention, and becomes a cooling heat holding mechanism that exhibits the cooling effect of the steering wheel even after parking for a long time under hot weather.
[0019]
When riding, the top heat mode is canceled simply by the passenger turning the steering wheel half a half, and the heat transport function (function to equalize the temperature in the pipe) is activated. As described above, since the heat transport speed of the heat pipe is extremely high, the upper portion of the rim that has been a high temperature portion is instantaneously cooled to the average value of the temperature of the entire rim.
[0020]
In this way, the rim reaches a temperature at which the total amount of heat retained is leveled, and the object of the present invention is achieved.
[0021]
However, in the midsummer environment, the maximum temperature of the rim that receives solar radiation exceeds 80 ° C, and in order to cool the rim to a temperature range where it can be grasped with bare hands (about 60 ° C or less), an appropriate amount of cooling is required. is there. In the present invention, in order to make the effect more effective, a heat storage body as a cold heat source was examined, and new ideas were incorporated into the material and the installation method.
[0022]
In the present invention, the action of the heat storage body is to increase the heat capacity of the low temperature portion of the steering wheel. Thus, the heat storage body is basically installed in a place where the position is low and the solar radiation is difficult to hit, for example, the lower part of the rim or the back side of the spoke supporting the lower part of the rim. By the way, the direction of the wheels at the time of parking is often directed straight in order to avoid unexpected vehicle behavior at the time of departure, so the steering wheel at the time of parking maintains a vertical relationship with a high probability. Also from this point, if the heat storage body is installed in the lower part of the rim or the like, the action of the heat storage body to increase the heat capacity of the low temperature portion of the steering wheel is exhibited with a high probability. Further, in light of the purpose of instant cooling of the present invention, the heat storage body is placed in contact with the heat pipe so as to be able to transfer heat, and when the heat transport function is activated, the cold heat is quickly supplied to the heat pipe. It is good to do.
[0023]
As the heat storage body referred to in the present invention, for example, a sensible heat storage body that stores heat in the form of sensible heat such as a lump of metal can be used. Since the metal lump is excellent in thermal conductivity, it is excellent in the speed of supplying cold heat, but has a small specific heat and requires a considerable weight. In addition, a latent heat storage material that stores heat in the form of latent heat, such as paraffins having a melting point in the range of 30 ° C. to 60 ° C. or metal salt hydrate, is also preferably used in the present invention. Since these have a latent heat of fusion several hundred times that of sensible heat of metals, it can be said that it is extremely advantageous from the viewpoint of heat capacity, but it is somewhat disadvantageous in the rate of supplying cold heat to the heat pipe because of its generally low thermal conductivity. It can be said.
[0024]
Accordingly, the present invention has found an installation method in which a latent heat storage material is enclosed inside a heat pipe as an installation method of a heat storage body that achieves both a heat capacity and a cold supply rate. As a result, the latent heat storage material comes into direct contact with the working fluid and can quickly release cold heat. Here, if the latent heat storage material is in the form of particles, that is, encapsulated in a capsule or the like, the effect of quickly releasing cold heat is further remarkable by ensuring a stable surface area in contact with the working fluid vapor. Become. The working fluid condenses on the surface of the individual heat accumulator particles, and heat exchange is performed in the form of so-called vapor phase heating, so that the stored heat of the heat accumulator can be released instantaneously.
[0025]
On the other hand, when installing a heat storage body in the pipe | tube of a rim | limb, there exists a concern about the filling amount of a heat storage body. However, the latent heat of fusion of a general latent heat storage material is 100 to 300 J / cm. ^Three Therefore, it is possible to maintain cold heat several hundred times as large as the heat capacity of the metal constituting the rim. For example, in the case of sodium sulfate decahydrate (melting latent heat 251 kJ / kg), a normal rim metal core (steel pipe, specific heat 0.44 kJ / kg / k) of about 50 kg is 20 ° C. at around 50 g. Hold the cold to cool to some extent.
[0026]
Furthermore, as an advantage of enclosing and installing the particulate heat storage body in the heat pipe, the particulate heat storage body stays at the lowermost part in the rim regardless of the direction of the steering wheel during parking, which is advantageous for keeping cold. In addition, when the function of the heat pipe is activated by the rotation of the steering wheel, the heat storage body moves closer to the high temperature portion where the position becomes lower, so that heat exchange with higher efficiency can be achieved.
[0027]
Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
[0028]
8A is an external view showing a general vehicle steering wheel, FIG. 8B is a sectional view taken along line 8B-8B in FIG. 8A, and FIG. It is sectional drawing which shows a rim core material.
[0029]
As shown in FIG. 8A, the steering wheel 180 includes a ring-shaped rim 10, spokes 20 that support the rim 10, and a hub 30 that is fixed to the column. The rim 10 has a diameter of about 400 mm. About 1 to 4 spokes 20 (three in the illustrated example) are provided.
[0030]
As shown in FIG. 8B, the rim 10 has a core material 11 made of steel or aluminum, and a cushion layer 12 formed by casting the core material 11 with foamed rubber or foamed resin. The cushion layer 12 gives the occupant a soft feel when the steering wheel 180 is gripped. Furthermore, on the surface layer of the cushion layer 12, a skin 13 made of real leather or synthetic leather is attached in order to give a high-quality appearance and feel.
[0031]
In many cases, a steel pipe is used as the rim core material 11, but in recent years, as shown in FIG. 8C, a core material 14 having an open cross section has also been used from the viewpoint of ease of processing. ing.
[0032]
(First embodiment)
FIG. 1A is an external view showing a steering wheel 110 incorporating a cooling device for a vehicle steering wheel 110 according to a first embodiment of the present invention, and FIG. 1B is 1B of FIG. It is sectional drawing which follows the -1B line.
[0033]
In the cooling device for a vehicle steering wheel 110 according to the first embodiment, the core material 11 of the rim 10 is constituted by a heat pipe 40.
[0034]
The heat pipe 40 is formed by degassing and decompressing a hollow portion in the pipe, injecting a working fluid, and sealing. The heat pipe 40 stops the heat transport function in the top heat mode state at the time of parking. On the other hand, with the rotation of the steering wheel 110 at the start of operation, the heat pipe 40 causes the condensed working fluid to recirculate mainly with gravity, and starts the operation of the heat transport function. For this reason, it is not always necessary to install a wick in the heat pipe 40, but a wick can be provided as appropriate in order to adjust the sensitivity of the operating conditions. The wick can be formed from fiber, wire mesh, sintered metal, or the like.
[0035]
As the pipe material of the core material 11, that is, the heat pipe 40, a steel pipe used for a normal steering wheel, and other metal pipes such as copper, stainless steel, aluminum, and magnesium that are easily available industrially are suitable. Used for. However, since it is used as the heat pipe 40, the gas sealability and the corrosion resistance against the working fluid must be taken into consideration. For this reason, inner surface plating, a double pipe, etc. can be used conveniently.
[0036]
Here, when the heat transport function is stopped, one factor that increases the temperature of the low temperature portion of the heat pipe 40, that is, the rim lower portion 15, is heat transfer from the high temperature portion through the metal. Therefore, in order to keep the cold in the rim lower part 15, it is preferable that the thermal conductivity of the tube material is small. A stainless steel pipe is an industrially easily available material from this viewpoint. The thermal conductivity of steel is 50 to 80 W / mk, stainless steel (SUS304) is 16 W / mk, aluminum is approximately 120 to 240 W / mk, and copper is 400 W / mk.
[0037]
Furthermore, stainless steel has a high tensile strength (about 50 kg / mm2) in terms of component strength and rigidity, so the pipe wall can be designed thinner than steel (about 30 kg / mm2 for carbon steel for pipes) It is preferable for suppressing heat conduction.
[0038]
As the working fluid, a known material can be used. However, pure water is preferable in consideration of the use temperature band and safety of the present technology. However, from the viewpoint of corrosiveness, etc., hydrocarbons, ammonia, alternative chlorofluorocarbons, alcohols, etc. depending on the material of the inner wall of the pipe, those whose melting point is below room temperature and whose critical point exceeds the applicable temperature of the present invention (about 100 ° C.) Can be appropriately selected.
[0039]
The injection amount of the working fluid is not particularly limited, but the present invention takes a thermosiphon-like heat transport configuration in which the condensate is refluxed mainly by gravity when the heat pipe 40 is operated, so that a larger amount than the capillary type is used. It is preferable to inject. However, if the injection amount of the working fluid is small, sufficient recirculation does not occur. If the injection amount is excessive, the temperature gradient of the liquid surface and the high temperature portion of the working fluid is large during operation and the heat transfer is hindered. For this reason, the injection amount of the working fluid is in the range of 3% to 50%, preferably 10 to 30%, of the internal volume of the tube.
[0040]
The operation of the first embodiment will be described.
[0041]
When parking in hot weather, the upper part of the rim is heated by sunlight and the lower part of the rim 15 is kept at the room temperature. Since the heat pipe 40 is in the top heat mode, the heat transport function is stopped. Even if the parking state lasts for several hours, the temperature difference between the part that receives solar radiation and the part that does not receive solar radiation is maintained.
[0042]
The top heat mode is canceled when the occupant turns the steering wheel 110 approximately half a turn at the start of driving. The rotation of the steering wheel 110 exhibits the switch function described above, and the heat pipe 40 starts the operation of the heat transport function that attempts to equalize the temperature in the pipe. Since the heat transport speed of the heat pipe is extremely fast, the upper part of the rim, which has been a high temperature part, is instantaneously cooled to approximately the average value of the temperature of the entire rim by the cold heat held in the lower part of the rim 15.
[0043]
As described above, according to the first embodiment, since the core material 11 of the rim 10 is composed of the heat pipe 40, it is parked for a long time under the hot sun without using energy such as electric power and becomes high temperature. There is an effect that the high temperature portion of the rim 10 can be quickly cooled to a temperature at which the rim 10 can be operated.
[0044]
In addition, by using stainless steel as the pipe material of the heat pipe 40, heat conduction from the high temperature portion is suppressed compared to the case of using steel or aluminum, and the cold heat in the rim lower portion 15 is easily maintained.
[0045]
(Second Embodiment)
FIG. 2 is a cross-sectional view corresponding to FIG. 1B of a steering wheel 120 incorporating a cooling device for a vehicle steering wheel 120 according to a second embodiment of the present invention.
[0046]
In the cooling device for the vehicle steering wheel 120 according to the second embodiment, the heat pipe 41 is disposed along the core member 14 of the rim 10.
[0047]
The core material 14 has a substantially U-shaped cross section and an open cross section. The heat pipe 41 is fitted from the opening side of the core material 14 and is disposed so as to be in close contact with the core material 14.
[0048]
The operation of the second embodiment is the same as that of the first embodiment. When the operation is started after the vehicle is parked under the hot sun, the heat pipe 41 operates the heat transport function as the steering wheel 120 rotates. Then, the upper part of the rim, which was a high temperature part, is cooled instantly.
[0049]
As described above, according to the second embodiment, since the heat pipe 41 is arranged along the core material 14 of the rim 10, the high temperature portion of the rim 10 that has been parked for a long time under the hot sun and becomes high temperature is instantly displayed. There is an effect that it can be cooled.
[0050]
Furthermore, in the second embodiment, since the core material 14 and the heat pipe 41 are separate bodies, the core material 14 and the heat pipe 41 can be designed with materials and structures that satisfy the requirements for establishment thereof, and the degree of freedom in design. Increases and the configuration becomes simpler.
[0051]
Moreover, it becomes the form which is easy to industrially mass-produce by using together the core material 14 which has an open cross section.
[0052]
(Third embodiment)
FIG. 3 is an external view showing a steering wheel 130 incorporating a cooling device for a vehicle steering wheel 130 according to a third embodiment of the present invention.
[0053]
The cooling device for a vehicle steering wheel 130 according to the third embodiment bends a straight tubular heat pipe 42 along the shape of the rim 10, and the core member 14 of the rim 10 is bent similarly to the second embodiment. A heat pipe 42 is arranged along the line.
[0054]
Further, both ends of the heat pipe 42 are folded back to the back side of the lower spoke 20 which is shaded at the position of the lower rim 15.
[0055]
The operation of the third embodiment is the same as that of the first and second embodiments. When the operation is started after parking in the hot sun, the heat pipe 42 is transported by heat as the steering wheel 130 rotates. The operation of the function starts, and the upper part of the rim, which has been a high-temperature part, is instantly cooled.
[0056]
As described above, according to the third embodiment, since the heat pipe 42 is disposed along the core member 14 of the rim 10, the high temperature portion of the rim 10 that has been parked for a long time under the hot sun and becomes high temperature is instantly displayed. There is an effect that it can be cooled.
[0057]
Furthermore, in the third embodiment, since both ends of the heat pipe 42 are folded back to the back side of the lower spoke 20, the design flexibility is high from the viewpoint of heat transfer with the cold heat source.
[0058]
In addition, since many ordinary heat pipes are straight pipes, the use of the core material 14 having an open cross section as shown in FIG.
[0059]
(Fourth embodiment)
FIG. 4 is a cross-sectional view corresponding to FIG. 1B of a steering wheel 140 incorporating a cooling device for a vehicle steering wheel 140 according to a fourth embodiment of the present invention.
[0060]
The vehicle steering wheel 140 cooling device according to the fourth embodiment includes a plurality of small-sized heat pipes 43 used in general for electronic parts and the like arranged in parallel along the core 11 of the rim 10. It is.
[0061]
The operation of the fourth embodiment is the same as that of the first to third embodiments. When the driving is started after the vehicle is parked under the hot sun, the plurality of heat pipes 43 are accompanied by the rotation of the steering wheel 140. Starts operation of the heat transport function, and the upper part of the rim, which has been a high-temperature part, is instantaneously cooled.
[0062]
As described above, according to the fourth embodiment, since the heat pipe 43 is disposed along the core material 11 of the rim 10, the high temperature portion of the rim 10 that has been parked for a long time under the hot sun and becomes high temperature is instantly There is an effect that it can be cooled.
[0063]
Furthermore, in the fourth embodiment, since a general-purpose heat pipe 43 is used, it is more easily industrially mass-produced.
[0064]
(Fifth embodiment)
FIG. 5A is an external view showing a steering wheel 150 in which a cooling device for a vehicle steering wheel 150 according to a fifth embodiment of the present invention is incorporated, and FIG. 5B is 5B of FIG. FIG. 5C is a cross-sectional view taken along line 5C-5C in FIG. 5A.
[0065]
As in the first embodiment, the cooling device for the vehicle steering wheel 150 according to the fifth embodiment includes the core material 11 of the rim 10 composed of the heat pipe 40, and further heats the heat storage body 50 that stores heat. It is provided in the heat pipe 40 so that it can be exchanged. The heat storage body 50 is disposed in the rim lower part 15. As shown in FIG. 5B, the heat storage body 50 is provided so as to surround the outer periphery of the heat pipe 40, and heat exchange with the working fluid in the heat pipe 40 is performed quickly.
[0066]
In addition, the heat storage body 50 may be a metal lump installed so that the outer periphery of the heat pipe 40 is wrapped with metal, or a form in which a latent heat storage material is enclosed by forming a double tube metal container outside the heat pipe 40.
[0067]
Moreover, since the back side of the lower spoke 20 is shaded, it is an excellent part as a part for holding cold. Therefore, as shown in FIG. 5C, the heat storage body 50 can be installed on the back side of the lower spoke 20. The thickness of the back side of the spoke 20 is not limited like the rim 10 gripped by the driver. Therefore, it can be said that it is a suitable site for securing the cold heat capacity. In FIG. 5C, reference numeral “21” indicates a spoke core material, and “22” indicates a cushion layer.
[0068]
The operation of the fifth embodiment will be described. When the operation is started after the vehicle is parked under the hot sun, the heat pipe 40 starts the operation of the heat transport function along with the rotation of the steering wheel 150. The upper part of the rim that was supposed to be cooled immediately. Furthermore, by providing the heat storage body 50, the heat capacity of the low temperature part is increased, and the rim 10 can be gripped with bare hands even when the maximum temperature of the rim 10 exceeds 80 ° C. in a midsummer environment. Cool to the region (about 60 ° C. or less). In addition, even when the vehicle is left in the sun for a long time, sufficient heat is retained by the heat storage body 50, and the effect of cooling the steering wheel 150 is sufficiently exhibited.
[0069]
As described above, according to the fifth embodiment, since the core material 11 of the rim 10 is constituted by the heat pipe 40, the high temperature portion of the rim 10 that has been parked for a long time under the hot sun and becomes high temperature is instantaneously cooled. There is an effect that can be.
[0070]
Furthermore, in the fifth embodiment, since the heat storage body 50 that stores heat is provided in the heat pipe 40 so as to be able to transfer heat, the heat capacity of the low temperature portion is increased, and the high cooling effect of the steering wheel 150 is provided for a long time. Can be ensured over the entire range.
[0071]
FIG. 5D is a cross-sectional view corresponding to FIG. 5C of a steering wheel incorporating a cooling device for a vehicle steering wheel according to a modification of the fifth embodiment.
[0072]
In this modified example, a part of the heat pipe 40 is guided to the back side of the lower spoke 20 as in the third embodiment, and the heat storage body 50 is provided to the folded heat pipe 40 so that heat can be transferred. is there. In such a configuration, the heat exchange efficiency between the heat storage body 50 and the working fluid in the heat pipe 40 is further increased in combination with the fact that the back side of the lower spoke 20 is excellent as a part that can retain cold heat and secure cold heat capacity. improves.
[0073]
(Sixth embodiment)
6A is an external view showing a steering wheel 160 in which a cooling device for a vehicle steering wheel 160 according to a sixth embodiment of the present invention is incorporated, and FIG. 6B is 6B of FIG. It is sectional drawing which follows the -6B line.
[0074]
In the cooling device for a vehicle steering wheel 160 according to the sixth embodiment, the core material 11 of the rim 10 is constituted by the heat pipe 40, and further, the heat storage body 51 that stores heat is provided in the heat pipe 40 so as to be capable of receiving and transferring heat. is there. The heat storage body 51 is disposed in the rim lower portion 15. As shown in FIG. 6B, the heat storage body 51 is provided in the pipe of the heat pipe 40, and heat exchange with the working fluid in the heat pipe 40 is quickly performed.
[0075]
The illustrated heat storage body 51 is obtained by encapsulating a heat storage material encapsulated in a heat pipe 40. Encapsulation prevents the heat storage material from adhering to the tube wall or blocking the vapor path when it repeatedly melts and solidifies. If the capsule diameter is too small, the vapor path between the particles is blocked by the condensed working fluid, resulting in poor heat exchange efficiency. On the other hand, when the capsule diameter is too large, the heat conduction to the core of the heat storage material is inferior, and the cold heat release rate decreases. Therefore, the heat storage body 51 is preferably a granular body having a particle size of about 2 mm to 10 mm. The shape of the heat accumulator 51 is a shape that can be easily obtained industrially, such as a sphere or a cylinder, and has no problem.
[0076]
A sufficient amount of the heat storage body 51 can be obtained as long as it can be stored in the low temperature portion of the pipe (about 1/3 of the volume in the pipe), but even if packed in a large amount, the effect is not impaired. However, in the case of filling an amount exceeding 1/2 of the pipe internal volume, it is possible to expect the function of delaying the temperature rise of the heating unit during parking as in the technique of Patent Document 1 described above. Care must be taken to block the path and to make it easier to dry up due to lack of hydraulic fluid.
[0077]
The heat storage body 51 suitable for the present invention contains a latent heat storage material that stores heat in the form of latent heat and has a melting point in the range of 30 ° C to 60 ° C. According to such a latent heat storage material, cold heat is accumulated at a temperature near room temperature, and a large amount of cold heat is supplied in a temperature range slightly lower than the temperature range where the steering wheel 160 cannot be gripped.
[0078]
As a specific material of such a latent heat storage material, a metal salt or a metal salt hydrate is preferable. For example, metal salt hydrates such as sodium sulfate decahydrate (melting point: 32 ° C.), sodium acetate trihydrate (55 ° C.), sodium acetate trihydrate + sodium nitrate mixture (about 47-50 ° C.) There are also paraffins having about 18 to 25 carbon atoms, which can be used as appropriate.
[0079]
However, the higher the density of the heat storage material, the greater the amount of heat stored in the limited volume. In particular, when the working fluid is water, if the specific gravity of the heat storage material is 1.0 or more, it is easier to hold the cold by settling in the working fluid. From this point of view, as a kind of latent heat storage material, for example, sodium sulfate decahydrate has a specific gravity of 1.46, and metal salt hydrate type is preferable to paraffin type.
[0080]
The operation of the sixth embodiment is the same as that of the fifth embodiment. When the operation is started after the vehicle is parked under the hot sun, the heat pipe 40 operates the heat transport function as the steering wheel 160 rotates. Then, the upper part of the rim, which was a high temperature part, is cooled instantly. Furthermore, by providing the heat storage body 51, the heat capacity of the low temperature part is increased, and the rim 10 is sufficiently cooled even in a midsummer environment. Further, even when the vehicle is left in the sun for a long time, sufficient heat is retained by the heat storage body 51, and the effect of cooling the steering wheel 160 is sufficiently exhibited.
[0081]
As described above, according to the sixth embodiment, the core material 11 of the rim 10 is composed of the heat pipe 40, so that the high temperature portion of the rim 10 that has been parked for a long time under the hot sun and becomes high temperature is instantaneously cooled. There is an effect that can be.
[0082]
Further, in the sixth embodiment, since the heat storage body 51 that stores heat is provided in the heat pipe 40 so as to be able to transfer heat, the heat capacity of the low temperature part is increased, and the high cooling effect of the steering wheel 160 is maintained for a long time. Can be ensured over the entire range.
[0083]
And since it is provided in the pipe | tube of the thermal storage body 51 heat pipe, the thermal storage body 51 will be in direct contact with a working fluid, can discharge | release a cold quickly, and can further improve the cooling effect of the steering wheel 160.
[0084]
Moreover, since the heat storage body 51 is a granular body, the surface area which contacts a working fluid is ensured stably and the effect which discharge | releases cold heat rapidly becomes further remarkable.
[0085]
Moreover, since the heat storage body 51 stores a latent heat storage material in the form of latent heat and contains a latent heat storage material having a melting point in the range of 30 ° C. to 60 ° C., it has several hundred times the latent heat of fusion compared to the sensible heat of metal. Therefore, the cooling effect of the steering wheel 160 can be further enhanced.
[0086]
Further, since the latent heat storage material is a metal salt or metal salt hydrate, it accumulates cold heat at a temperature near room temperature and supplies a large amount of cold heat at a temperature range slightly lower than the temperature range where the steering wheel 160 cannot be gripped. can do.
[0087]
(Seventh embodiment)
FIG. 7A is an external view showing a steering wheel 170 incorporating a cooling device for a vehicle steering wheel 170 according to a seventh embodiment of the present invention, and FIG. 7B is 7B of FIG. It is sectional drawing which follows the -7B line.
[0088]
As in the sixth embodiment, the cooling device for the vehicle steering wheel 170 according to the seventh embodiment includes the core material 11 of the rim 10 composed of the heat pipe 40, and is capable of transferring heat to the granular heat storage body 51. The heat pipe 40 is enclosed in a pipe. Furthermore, the rim lower part 15 is covered with a heat insulating material 60 when a position where the direction of the wheel is directed in the straight traveling direction is used as a reference, and a heat insulating coating layer is formed.
[0089]
When the parking time takes a long time, the air temperature around the steering wheel may rise to around 60 ° C. Moreover, the rim lower part 15 may receive solar radiation depending on the direction of sunlight. Assuming these cases, it is desirable to keep the rim lower part 15 cold by the heat insulating material 60 as in the seventh embodiment.
[0090]
As a material of the heat insulating material 60, a generally known material such as a foam or a fiber nonwoven fabric can be appropriately used. The surface of the heat-insulating coating layer is preferably a highly reflective surface that hardly absorbs solar radiation or ambient radiation, and is preferably a cover formed of an aluminum sheet, a resin cover that has been subjected to metal plating, or metallic coating using aluminum flakes. In addition, a white skin or a coating with white paint also has a high reflectivity and has a cooling effect.
[0091]
As in the case of the sixth embodiment, the operation of the seventh embodiment is that the heat pipe 40 activates the heat transport function along with the rotation of the steering wheel 170 when the operation is started after parking under the hot sun. The upper part of the rim, which has started and became a high-temperature part, is immediately cooled. Furthermore, by providing the heat storage body 51, the heat capacity of the low temperature part is increased, and the rim 10 is sufficiently cooled even in a midsummer environment. Further, even when the vehicle is left in the sun for a long time, sufficient heat is retained by the heat storage body 51, and the effect of cooling the steering wheel 170 is sufficiently exhibited. In addition, since the lower portion of the rim 10 is cooled by the heat insulating material 60 and sufficient cold heat is maintained, the effect of cooling the steering wheel 170 is more fully exhibited.
[0092]
As described above, according to the seventh embodiment, since the rim lower part 15 is covered with the heat insulating material 60 when the position where the direction of the wheel is directed in the straight traveling direction is used as a reference, in addition to the effect of the sixth embodiment. Furthermore, the high cooling effect of the steering wheel 170 can be further ensured over a long period of time.
[0093]
【Example】
Examples of the present invention will be described below.
[0094]
A stainless steel pipe having an outer diameter of 20 mm and an inner diameter of 16 mm was bent to produce a tubular rim having an outer diameter of 400 mm. A working fluid inlet was provided in a part of the tubular rim. The inlet is made of copper. Inside the tubular rim, a capsule-type latent heat storage material was sealed in advance as a heat storage body. The capsule-type latent heat storage material was adjusted by the method described later. The encapsulation amount of the capsule-type latent heat storage material was 100 g. This amount of the capsule-type latent heat storage material accounted for about half of the inner volume of the tubular rim.
[0095]
Next, 60 g of pure water was injected as a working fluid from the inlet into the tube of the tubular rim, and the inlet was temporarily tightened. Thereafter, the entire tubular rim was heated to 125 ° C., the temporary fastening was released, and the non-condensable gas in the pipe was expelled. Thereafter, the inlet was again crimped and cut to seal the working fluid. The amount of working fluid (pure water) after sealing the inlet was about 50 g.
[0096]
As the heat storage material, an STL latent heat storage material sodium acetate / sodium nitrate mixed heat storage material (melting point: 50 ° C., latent heat of fusion: 205 KJ / Kg) manufactured by Mitsubishi Chemical Corporation was used. This heat storage material was melt-filled into a polypropylene tube having an outer diameter of 4 mm and a tube wall thickness of 0.15 mm, and then the tube was thermocompression-bonded at intervals of 5 mm and cut. Thus, the capsule-type latent heat storage material was adjusted, and a simple granular heat storage body was obtained.
[0097]
The rim thus obtained was welded to the spokes of an actual vehicle steering wheel, and a black foamed urethane tape was uniformly wound to a thickness of about 3 mm as a cushion layer. Further, as shown in FIG. 7A, a urethane tape is further wound to a thickness of 2 mm in the vicinity of the rim lower portion 15, and a layer of aluminum reflective tape is wound on the surface thereof. As an example.
[0098]
Further, as Comparative Example 1, a steering wheel without heat pipe action without enclosing the working fluid was manufactured. The steering wheel of Comparative Example 1 was prototyped in the same procedure as in the example except that the working fluid was not sealed.
[0099]
Further, as Comparative Example 2, an existing steering wheel was used.
[0100]
(Results of actual vehicle test)
The actual vehicle equipped with each steering wheel of Example, Comparative Example 1 and Comparative Example 2 was parked outdoors on a fine day in July, and the temperature change of each steering wheel was measured. The temperature measurement point is the surface of the rim upper end and rim lower end. The temperature was measured using a thermocouple. The measuring method starts parking at 10 am, measures the temperature at parking at noon 2 hours later, and immediately after that, the steering wheel is reversed, and the temperatures 10 seconds and 30 seconds after reversing are measured. It was measured. The measurement results are shown in Table 1 below.
[0101]
[Table 1]

[0102]
In the case of Comparative Example 1 (no working fluid) and Comparative Example 2 (current steering wheel), the temperature at the top of the rim drops only about 10 ° C. even after 30 seconds have passed since the turnover, and the passenger is bare It was about 70 ° C., which is higher than about 60 ° C., which is the temperature range that can be gripped with the rim, and cooling of the heated rim top was insufficient.
[0103]
On the other hand, in the case of the embodiment of the present invention, the temperature at the top of the rim drops by 17.3 ° C. just after 10 seconds have passed since the reversal, and is a temperature region in which the occupant can grasp with bare hands. If it is cooled to around 60 ° C and 30 seconds have passed after reversing, the temperature at the top of the rim will drop by 25.1 ° C to 53.1 ° C, and the temperature range where the passenger can hold it with bare hands It was sufficiently cooled to about 60 ° C. or less.
[0104]
As a result, the rim is used as a heat pipe in the steering wheel, so that the high temperature part of the rim that has become hot due to parking for a long time under the sun can be cooled instantly, and the latent heat storage material is enclosed in the heat pipe. By doing so, it was confirmed that the cooling effect of the steering wheel could be further enhanced.
[Brief description of the drawings]
FIG. 1 (A) is an external view showing a steering wheel incorporating a cooling device for a vehicle steering wheel according to a first embodiment of the present invention, and FIG. 1 (B) is the same drawing (A). It is sectional drawing which follows the 1B-1B line.
FIG. 2 is a cross-sectional view corresponding to FIG. 1B of a steering wheel incorporating a vehicle steering wheel cooling device according to a second embodiment of the present invention.
FIG. 3 is an external view showing a steering wheel incorporating a cooling device for a vehicle steering wheel according to a third embodiment of the present invention.
FIG. 4 is a cross-sectional view corresponding to FIG. 1B of a steering wheel incorporating a vehicle steering wheel cooling device according to a fourth embodiment of the present invention.
FIG. 5 (A) is an external view showing a steering wheel incorporating a cooling device for a vehicle steering wheel according to a fifth embodiment of the present invention, and FIG. 5 (B) is the same drawing (A). FIG. 5C is a cross-sectional view taken along line 5C-5C in FIG. 5A, and FIG. 5D is a vehicle according to a modified example of the fifth embodiment. It is sectional drawing equivalent to FIG.5 (C) of the steering wheel incorporating the cooling device of the steering wheel for vehicles.
FIG. 6 (A) is an external view showing a steering wheel incorporating a vehicle steering wheel cooling device according to a sixth embodiment of the present invention, and FIG. 6 (B) is the same drawing (A). It is sectional drawing which follows the 6B-6B line.
FIG. 7 (A) is an external view showing a steering wheel incorporating a cooling device for a vehicle steering wheel according to a seventh embodiment of the present invention, and FIG. 7 (B) is the same drawing (A). It is sectional drawing which follows the 7B-7B line.
8A is an external view showing a general vehicle steering wheel, FIG. 8B is a sectional view taken along line 8B-8B in FIG. 8A, and FIG. 8C. These are sectional drawings which show another rim core material.
[Explanation of symbols]
110, 120, 130, 140, 150, 160, 170 ... steering wheel for vehicle
10 ... Rim
11, 14 ... Rim core
12 ... Cushion layer
15 ... Rim lower part (lower part of the rim when the wheel is oriented in the straight direction)
20 ... spoke
40, 41, 42, 43 ... heat pipe
50, 51 ... thermal storage
60 ... Insulation

Claims (9)

In a vehicle steering wheel having a ring-shaped rim,
The core material of the rim is composed of a heat pipe, and the heat pipe passes through the lower portion of the rim when the wheel is oriented in the straight direction, and the lower portion of the rim is the rim when parked. A cooling device for a steering wheel for a vehicle, characterized in that the temperature becomes a low-temperature part whose temperature is lower than that of the upper part of the motor, and the heat capacity of the low-temperature part becomes a cold heat source . In a vehicle steering wheel having a ring-shaped rim,
A heat pipe is disposed along the core of the rim, and the heat pipe passes through the lower portion of the rim when the wheel is oriented in the straight direction, and the lower portion of the rim is parked. A cooling device for a steering wheel for a vehicle, characterized in that a low temperature part having a temperature lower than that of the upper part of the rim is provided, and a heat capacity of the low temperature part becomes a cold heat source .   3. The cooling device for a vehicle steering wheel according to claim 1, wherein a heat storage body for storing heat is provided in the heat pipe so as to be able to transfer heat. 4.   The said heat storage body is provided in the pipe | tube of the said heat pipe, The cooling device of the steering wheel for vehicles of Claim 3 characterized by the above-mentioned.   The said heat storage body is a granular body, The cooling device of the steering wheel for vehicles of Claim 3 or Claim 4 characterized by the above-mentioned.   6. The vehicle according to claim 3, wherein the heat storage body stores a heat in the form of latent heat and contains a latent heat storage material having a melting point in the range of 30 ° C. to 60 ° C. 6. Steering wheel cooling device.   The cooling apparatus for a vehicle steering wheel according to claim 6, wherein the latent heat storage material is a metal salt or a metal salt hydrate.   The cooling device for a steering wheel for a vehicle according to any one of claims 1 to 7, wherein a pipe material of the heat pipe is stainless steel.   The cooling device for a vehicle steering wheel according to any one of claims 1 to 8, wherein a lower portion of the rim is covered with a heat insulating material when a position where the direction of the wheel is directed in a straight traveling direction is used as a reference.

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