WO2019031122A1

WO2019031122A1 - Casing for vehicle air-conditioning unit and vehicle air-conditioning duct

Info

Publication number: WO2019031122A1
Application number: PCT/JP2018/025518
Authority: WO
Inventors: 神谷　敏文
Original assignee: 株式会社デンソー
Priority date: 2017-08-10
Filing date: 2018-07-05
Publication date: 2019-02-14
Also published as: JP2019034592A

Abstract

This casing (12) for a vehicle air-conditioning unit (10) comprises a resin-based composite material. The resin-based composite material is composed of a resin substrate and a fibrous cellulose material containing cellulose.

Description

Casing of air conditioning unit for vehicle and air conditioning duct for vehicle

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on Japanese Patent Application No. 2017-155873 filed on Aug. 10, 2017, the contents of which are incorporated herein by reference.

The present disclosure relates to a casing of a vehicle air conditioning unit and a vehicle air conditioning duct.

Generally, the casing of the vehicle air conditioning unit and the vehicle air conditioning duct are made of a resin-based composite material in which a polypropylene resin and talc are blended.

Patent Document 1 discloses a casing of a vehicle air conditioning unit. The casing is made of a resin-based composite material in which a polypropylene resin and glass hollow spheres are blended.

JP, 2015-51657, A

By the way, for the casing of the air conditioning unit for a vehicle and the air conditioning duct for a vehicle, it is required to reduce the weight and to reduce the combustibility. The demand for weight reduction is to realize low fuel consumption of the vehicle by reducing the weight of the on-vehicle product. Low flammability is required for products mounted in the passenger compartment. Keeping the flammability low means keeping the burning rate low, that is, slowing the combustion.

According to the casing of Patent Document 1 described above, since the hollow glass sphere has a lower specific gravity than the resin, weight reduction of the casing can be realized. However, Patent Document 1 does not describe until the flammability of the casing can be suppressed to a low level.

In view of the above-described point, the present disclosure aims to provide a casing of a vehicle air conditioning unit and a vehicle air conditioning duct that can be reduced in weight and incombustibility.

According to one aspect of the present disclosure, the casing of the vehicle air conditioning unit is made of a resin-based composite material, and the resin-based composite material contains a resin as a base material and cellulose, and is fibrous. It is blended with a cellulose material.

Cellulose materials have a lower specific gravity than resins. For this reason, according to this, the casing can be reduced in weight as compared with the case where no cellulose material is blended. Furthermore, according to this, compared with the case where the cellulose material is not blended, the flammability of the casing can be suppressed low.

Further, according to another aspect of the present disclosure, the air conditioning duct for a vehicle is made of a resin-based composite material, and the resin-based composite material contains a resin as a substrate and cellulose and is fibrous. It is blended with a cellulose material.

Cellulose materials have a lower specific gravity than resins. For this reason, according to this, it is possible to reduce the weight of the air conditioning duct for vehicle as compared with the case where the cellulose material is not blended. Furthermore, according to this, compared with the case where a cellulose material is not mix | blended, the combustibility of the air-conditioning duct for vehicles can be restrained low.
In addition, the parenthesized reference symbol attached to each component etc. shows an example of the correspondence of the component etc. and the specific component etc. as described in the embodiment to be described later.

It is a figure which shows the air-conditioning unit in 1st Embodiment. It is a figure which shows the air-conditioning duct in 2nd Embodiment.

Hereinafter, embodiments of the present disclosure will be described based on the drawings. In the following embodiments, parts that are the same as or equivalent to each other will be described with the same reference numerals.

First Embodiment
The air conditioning unit 10 of this embodiment shown in FIG. 1 will be described. The air conditioning unit 10 is a vehicle air conditioning unit that constitutes a part of a vehicle air conditioner. The air conditioning unit 10 is mounted on the vehicle front side of the front seat in the vehicle compartment. More specifically, this air conditioning unit 10 is disposed inside the instrument panel. The air conditioning unit 10 blows the air that has passed through the heat exchanger toward the vehicle interior.

As shown in FIG. 1, the air conditioning unit 10 includes a casing 12, a blower 14, an evaporator 16, and a heater core 18.

The casing 12 constitutes an outer shell of the air conditioning unit 10. The casing 12 is an air passage forming member that internally defines an air passage 122 through which air flowing into the vehicle compartment flows. The casing 12 accommodates the fan 142, the evaporator 16, the heater core 18 and the like of the blower 14 therein. The casing 12 is provided with a plurality of

suction openings

124a and 124b and a plurality of

blowout openings

126a and 126b. Each of the plurality of

suction openings

124 a and 124 b is an opening for sucking the inside air and the outside air into the interior of the casing 12. Each of the plurality of

blowout openings

126a and 126b is an opening for allowing air to flow out from the inside of the casing 12 to the outside. Each of the plurality of

outlet openings

126a and 126b is connected to each of a plurality of outlets provided in the vehicle compartment via an air conditioning duct (not shown). The blowout opening 126a is a face opening of the plurality of blowout openings. The face opening 126a is connected to a face outlet provided in the vehicle compartment. The blowout opening 126b is a defroster opening of the plurality of blowout openings. The defroster opening 126b is connected to a defroster outlet provided in the vehicle compartment.

In the casing 12, divided shapes which are shapes obtained by dividing the casing 12 into a plurality of pieces are combined. The casing 12 is made of a resin-based composite material described later.

The blower 14 forms an air flow toward the vehicle interior. The blower 14 has a fan 142 and a blower motor 144. The blower motor 144 is a drive unit that rotates the fan 142.

The evaporator 16 is a heat exchanger for cooling which cools air while evaporating the refrigerant by heat exchange between the air and the refrigerant of the refrigeration cycle. The heater core 18 is a heat exchanger for heating which heats air by heat exchange between the air and engine cooling water.

Although not shown, the air conditioning unit 10 includes an air mix door, a blowout mode door, an actuator, a temperature sensor, and a door position sensor.

The air mix door is a temperature control door that adjusts the mixing ratio of the cold air from the evaporator 16 and the warm air from the heater core 18 to adjust the temperature of the air conditioning air. The blowout mode door selectively opens and closes the plurality of

blowout openings

126a and 126b. When the blowout mode door selectively opens and closes the plurality of

blowout openings

126a and 126b, the blowout modes such as the face mode and the foot mode are realized. The actuator drives the various doors described above. The temperature sensor detects the air temperature inside the casing 12. The position sensor detects the operating position of various doors.

In the air conditioning unit 10 configured as described above, an air flow toward the vehicle interior is formed inside the casing 12 by the blower 14 as indicated by the arrows in FIG. 1. At this time, air flows into the interior of the casing 12 from any of the plurality of

suction openings

124 a and 124 b. The air that has flowed into the interior of the casing 12 passes through the heat exchanger such as the evaporator 16 and flows out from any of the plurality of

blowout openings

126a, 126b. Outflowed air is blown out from the air outlet into the vehicle compartment via an air conditioning duct (not shown).

Next, the resin-based composite material constituting the casing 12 will be described. Hereinafter, the resin-based composite material is simply referred to as a composite material.

This composite material contains a resin as a base material and a cellulose material. In this composite material, the resin has a higher blending ratio than the cellulose material. In addition, "blending" means combining a plurality of materials. "Composition" does not mean up to a large or small proportion of the composition.

The resin is an olefin-based thermoplastic resin. The olefin-based thermoplastic resin is a general purpose resin with the lowest specific gravity among general purpose resins. Olefin-based thermoplastic resins are inexpensive. The olefin-based thermoplastic resin is excellent in the environmental resistance to withstand use in an environment with temperature change, the resistance to a drug, and the like. Therefore, it is preferable to use an olefin-based thermoplastic resin as the resin of the composite material constituting the casing 12. Examples of the olefin-based thermoplastic resin include polypropylene and polyethylene.

The cellulosic material comprises cellulose as a component of cellulosic material. Cellulose is a carbohydrate represented by the molecular formula (C ₆ H ₁₀ O ₅ ) n. The cellulose material includes not only cellulose in a single state but also cellulose in a state of being bound to other compounds. Moreover, a cellulose material is obtained by disentangling a woody material into a fibrous form. Thus, the cellulosic material is fibrous. Fibrous means that the aspect ratio, which is the ratio of length to width, is greater than one. The fibrous form includes a form called fiber and a form called needle-like. The cellulose material may, for example, be cellulose nanofibers in the form of fibers alone, and lignocellulose nanofibers in the form of fibers combined with lignin and in the form of fibers. Nanofiber means that the width of the fiber is nanometer size.

The cellulose material has lower specific gravity and higher rigidity than the olefin-based thermoplastic resin. The composite material may include other materials other than the cellulose material.

The casing 12 is manufactured by injection molding using this composite material. For example, before injection molding, the resin and the cellulose material are mixed to produce pellets. Then, using the pellets, injection molding is performed on a mold for forming the casing 12. Thereby, the casing 12 is manufactured.

Next, the effects of the casing 12 according to the present embodiment will be described separately in the items of weight reduction, high rigidity, manufacturing aspect, and flammability.

(Regarding weight reduction and high rigidity)
In recent years, the spread of vehicles with low fuel consumption has been progressing as a vehicle trend. Reduction of vehicle weight, which affects vehicle fuel efficiency, is regarded as an important issue. Weight reduction is considered to be an important issue also in air conditioning units that are in-vehicle parts. For this reason, in order to reduce the weight of the air conditioning unit, conventionally, the reduction of the amount of use of the material constituting the casing has been considered. In addition, reduction in specific gravity of the material constituting the casing has also been studied.

In the study of reduction of the amount of material used, miniaturization of the air conditioning unit and thinning of the casing of the air conditioning unit were considered. However, there is a limit to the miniaturization of the air conditioning unit. In addition, when the thickness of the casing is too thin, there are problems such as deterioration in moldability in injection molding of the casing and reduction in rigidity of the casing. Furthermore, when the thickness of the casing is too thin, there is a problem that the casing is easily burned. As described above, there is a limit to thinning the casing.

The examination result about reduction in specific gravity of material is explained. The air conditioning unit is required not to be broken or deformed by the vibration of the vehicle or the impact when traveling. Also, the environment to which the air conditioning unit is exposed has a wide range of temperature change from low temperature to high temperature. For this reason, polypropylene-based composite materials are generally used as materials used for the casing, which are cheap, have a low specific gravity, have a certain degree of rigidity, and have good environmental resistance. In this composite material, polypropylene as a base material and talc as a reinforcing material are blended. Reinforcing materials are used to increase the stiffness of the material.

Polypropylene is the lightest material in general purpose resins. For this reason, it is difficult to switch the resin to a low specific gravity material. Therefore, in order to reduce the specific gravity of the material, a method of reducing the amount of blended talc has been studied. However, reducing the talc reduces the stiffness of the material. For this reason, in the method of reducing the compounding amount of talc, a great weight reduction effect can not be obtained.

Therefore, the inventor focused on the cellulose material as a compounding material to be compounded in the composite material. That is, the casing 12 of the present embodiment is made of a composite material in which a resin and a cellulose material are blended.

The cellulose material has a lower specific gravity than the olefin resin. Therefore, the specific gravity of the material constituting the casing 12 can be reduced as compared to the case where the cellulose material is not blended in the composite material. That is, the weight of the casing 12 can be reduced.

In the casing 12 of the present embodiment, a cellulose material is used as a compounding material instead of conventionally used talc. Cellulose materials have lower specific gravity and higher stiffness than talc. The cellulose material has a strength of several tens of times or more despite the specific gravity of about 60% of that of talc. Furthermore, the cellulose material is fibrous. Thus, the aspect ratio of the cellulosic material is higher than that of talc.

Therefore, according to the casing 12 of the present embodiment, when the volume ratio of the compounding material to the entire composite material is compared to be the same, weight saving of the casing is realized while the rigidity is improved compared to the conventional casing compounded with talc. Can. Further, according to the casing 12 of the present embodiment, even when the casing 12 is thinned, rigidity equivalent to that of the conventional casing can be secured, as compared with the conventional casing containing talc. Thus, by using a cellulose material as the compounding material, weight reduction of a resin molded product such as the casing 12 of the air conditioning unit 10 can be realized without changing the product shape.

(With respect to manufacturing)
The casing of Patent Document 1 and the casing 12 of the present embodiment are compared. The casing of Patent Document 1 is made of a composite material in which hollow glass spheres are blended instead of talc. Glass hollow spheres have lower specific gravity than resins because they are hollow in the middle. For this reason, according to the casing of patent document 1, weight reduction of a casing is realizable.

However, the casing of Patent Document 1 has many problems in the manufacturing of the casing. The casing is manufactured by injection molding. For example, when mixing a resin and a glass hollow sphere, the glass hollow sphere may break. Moreover, in order to make specific gravity of a composite material lower, it is possible to raise the hollow rate of a glass hollow sphere. In order to increase the hollow ratio, it is necessary to make the glass hollow sphere larger. In general, if the size of the compounded material mixed into the resin is large, the flowability of the material at the time of injection molding is deteriorated. For this reason, injection molding becomes difficult when the glass hollow sphere is enlarged. In addition, there is a concern that the surface of the molding equipment and the molding die may be damaged by the fact that the glass hollow spheres hit the surface of the molding equipment and the molding die during injection molding.

On the other hand, in the casing 12 of the present embodiment, a cellulose material is used as the compounding material. For this reason, the various subjects in the manufacture surface of the above-mentioned casing which generate | occur | produce by using glass hollow sphere can be avoided.

That is, since the cellulose material is not hollow spheres, there is no risk of cracking. With cellulosic materials, there is no need to increase the size to lower the specific gravity of the composite. For this reason, the deterioration of the flowability of the material by increasing the size can be avoided. Also, cellulose materials are less rigid than glass. For this reason, the damage property to the molding equipment and molding die at the time of injection molding is also low. Therefore, the durability of the molding equipment and the molding die against damage can be made equal to that of the prior art. From this, the conventional manufacturing method can be adopted as it is. Therefore, according to the casing 12 of the present embodiment, the casing 12 can be manufactured without introducing a new manufacturing facility, and the influence on the cost can be suppressed.

(With regard to flammability)
The composite material constituting the casing 12 of the present embodiment contains a cellulose material as a compounding material. For this reason, when the volume ratio of the blended material to the entire composite material is compared to be the same, it is possible to suppress the burning rate lower than that of the composite material blended with talc as the blended material. It became clear from the result of. That is, according to the casing 12 of this embodiment, it turned out that it is effective in suppressing that resin melts and drops out by the heat from a fire point.

Therefore, for example, compared with the conventional casing in which talc is blended, even if the thickness of the casing 12 is reduced, the same combustibility as the conventional casing can be secured. Thus, since the flammability can be suppressed to a low level, the composite material of the present embodiment can be used as a material constituting the casing 12.

Second Embodiment
The air conditioning duct 20 of the present embodiment shown in FIG. 2 will be described. The air conditioning duct 20 is a vehicle air conditioning duct mounted in a vehicle compartment. The air conditioning duct 20 guides the air flowing out of the air conditioning unit 10 shown in FIG. 1 to the air outlet provided in the vehicle compartment. The air conditioning duct 20 is an air passage forming member that internally forms an air passage through which air flowing into the vehicle compartment flows.

The air conditioning duct 20 has a unit side connection port 202. The unit side connection port 202 is connected to the face opening 126 a of the air conditioning unit 10 shown in FIG. 1. Further, the air conditioning duct 20 has a center side connection port 204 and a side side connection port 206. The center side connection port 204 and the side side connection port 206 are respectively connected to a center face outlet and a side face outlet provided in an instrument panel (not shown). Thus, the air conditioning duct 20 connects the face opening 126a of the air conditioning unit 10 to the center face outlet and the side face outlet.

In the face mode, air that has been heat-exchanged with the heat exchanger such as the evaporator 16 inside the air conditioning unit 10 flows out from the face opening 126 a of the air conditioning unit 10. The air flowing out of the air conditioning unit 10 flows through the inside of the air conditioning duct 20 toward the center face outlet and the side face outlet, and then blown out into the vehicle compartment from the center face outlet and the side face outlet.

The air conditioning duct 20 is made of the composite material of the first embodiment. For this reason, the air conditioning duct 20 of the present embodiment exhibits the same effect as that of the first embodiment.

(Other embodiments)
(1) In each of the above embodiments, a cellulose material is used as a reinforcing material for the composite material constituting the casing 12 and the air conditioning duct 20, instead of talc. However, both talc and a cellulose material may be used as a reinforcing material.

That is, a part of talc may be replaced with a cellulose material as compared with a conventional composite material in which talc is blended. Thereby, the compounding ratio of talc to the composite material can be reduced, and the specific gravity of the composite material can be reduced. As mentioned above, the cellulosic material is more rigid and has a higher aspect ratio than talc. Therefore, even if the blending ratio of the cellulose material to the composite material is small, the blending ratio of talc can be greatly reduced.

(2) In said each embodiment, in the composite material which comprises the casing 12 and the air-conditioning duct 20, the cellulose material was used as a reinforcing material. In other words, the blending ratio of the cellulose material to the composite material is the blending ratio at which the reinforcing effect can be obtained. However, the blending ratio of the cellulose material may be lower than the blending ratio at which the reinforcing effect is obtained. In this case, even if the reinforcing effect is not obtained, the effect of suppressing the flammability can be obtained.

(3) In each of the above embodiments, an olefin resin is used as the resin of the composite material. However, an engineering plastic such as polybutylene terephthalate may be used as the resin of the composite material.

(4) In the first embodiment, the air conditioning unit 10 is mounted on the vehicle front side of the front seat in the vehicle interior. However, the air conditioning unit may be mounted on the side or the ceiling of the rear seat in the vehicle compartment.

(5) In the second embodiment, the air conditioning duct 20 connects the face opening 126a of the air conditioning unit 10 to the center face outlet and the side face outlet. However, the air conditioning duct may connect the other air outlet of the air conditioning unit and the other air outlet of the vehicle interior. For example, the air conditioning duct may connect a blowout opening of the air conditioning unit and a rear seat outlet provided at the rear of the vehicle than the front seat.

(6) The present disclosure is not limited to the above-described embodiment, and can be appropriately modified within the scope of the claims, and includes various modifications and variations within the equivalent range. Moreover, said each embodiment is not mutually irrelevant and can be combined suitably, unless the combination is clearly impossible. Further, in each of the above-described embodiments, it is needless to say that the elements constituting the embodiment are not necessarily essential except when clearly indicated as being essential and when it is considered to be obviously essential in principle. Yes. Further, in the above embodiments, when numerical values such as the number, numerical value, amount, range, etc. of constituent elements of the embodiment are mentioned, it is clearly indicated that they are particularly essential and clearly limited to a specific number in principle. It is not limited to the specific number except when it is done. Further, in the above embodiments, when referring to materials, shapes, positional relationships, etc. of constituent elements etc., unless specifically stated otherwise or in principle when limited to a specific material, shape, positional relationship, etc., etc. It is not limited to the material, the shape, the positional relationship, etc.

(Summary)
According to the first aspect shown in part or all of each of the above-described embodiments, the casing of the air conditioning unit for a vehicle is made of a resin-based composite material. The resin-based composite material contains a resin as a base material and cellulose and is blended with a fibrous cellulose material.

Further, according to the second aspect, the resin is an olefin-based thermoplastic resin. The olefin-based thermoplastic resin is the resin with the lowest specific gravity among general purpose resins. For this reason, in order to reduce the weight of the casing, it is preferable to use an olefin-based thermoplastic resin as the resin.

Further, according to the third aspect, the vehicle air conditioning duct is made of the resin-based composite material. The resin-based composite material contains a resin as a base material and cellulose and is blended with a fibrous cellulose material.

Further, according to the fourth aspect, the resin is an olefin-based thermoplastic resin. The olefin-based thermoplastic resin is the resin with the lowest specific gravity among general purpose resins. For this reason, in order to reduce the weight of the air conditioning duct for vehicles, it is preferable to use an olefin-based thermoplastic resin as the resin.

Claims

A casing of a vehicle air conditioning unit configured of a resin-based composite material, comprising:
The casing of a vehicle air conditioning unit, wherein the resin-based composite material contains a resin as a base material, cellulose, and a fibrous cellulose material.
The casing of a vehicle air conditioning unit according to claim 1, wherein the resin is an olefin-based thermoplastic resin.
A vehicle air conditioning duct composed of a resin-based composite material, comprising:
The air-conditioning duct for a vehicle, wherein the resin-based composite material contains a resin as a base material, cellulose, and a fibrous cellulose material.
The air conditioning duct for a vehicle according to claim 3, wherein the resin is an olefin-based thermoplastic resin.