JPS6343813A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To control the upper limit of the oxygen concentration in the car compartment by installing a partial pressure regulating means which regulates the partial pressure difference between the both interface parts of an oxygen concentrating membrane which is formed by a partial pressure difference generating means, to a prescribed value or less. CONSTITUTION:In an oxygen concentrating device 70, the space in a hollow body 81 in which oxygen concentrating membranes 82 are laminated communicates to the suction side of a vacuum pump 71 through an oxygen leading-out duct 77, and an oxygen feeding duct 74 to the car compartment is connected onto the discharge side of the vacuum pump 71. The vaccum pump 71 generates a partial pressure difference state between the air feeding side interface part and the oxygen taking-out interface part of the oxygen concentrating membrane 82. In the above-described air conditioner, an outside air introducing duct 88 is installed onto the oxygen leading-out duct 77, and a negative pressure control valve 89 is installed onto the outside air introducing duct 88. When the intake negative pressure of the vaccum pump 71 becomes over a prescribed value, outside air is introduced into the above-described duct 77 by opening the above-described valve 89, and the excessive concentration of oxygen is prevented.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a vehicle air conditioner.

(Prior art) In general, vehicles, especially automobiles, provide a comfortable riding environment for passengers regardless of the climate (especially temperature) and driving conditions, and also prevent fogging and frost on the windows so that the driver can see clearly. Air conditioning equipment is installed to ensure safe and comfortable driving.

By the way, recent air conditioners (hereinafter simply referred to as air conditioners) have not only conventional air conditioning functions such as heating, cooling, humidification, and dehumidification, but also the function of conditioned air supplied to the vehicle interior. Products with an oxygen enrichment function that increases the amount of oxygen have been proposed (for example, in JP-A-5
9-212632).

This air conditioner with an oxygen enrichment function is equipped with an oxygen enrichment device that separates and removes nitrogen from the air to produce oxygen-enriched air, and the oxygen enrichment device separates and removes nitrogen from the air to produce oxygen-enriched air. Enriched air is supplied into the vehicle interior to make the interior air oxygen-enriched, which helps occupants recover from fatigue, prevents drowsiness, and motion sickness, creating a comfortable riding environment.

Generally, as the oxygen enrichment device, one using an oxygen enrichment membrane is often used. This oxygen enrichment device using an oxygen enrichment membrane is provided with an external air supply path on one side of the oxygen enrichment membrane and an oxygen outlet path on the other side, and further includes a meat interface of the oxygen enrichment membrane. A partial pressure difference forming means is provided to form a predetermined partial pressure difference therebetween, and the air supply path side supply air Oxygen-enriched air to be supplied into the vehicle interior is generated by permeating the oxygen inside through the oxygen-enriching membrane to the oxygen outlet path side.

(Problem to be Solved by the Invention) However, the means for forming a partial pressure difference described in "2" generally forms a partial pressure difference by creating a negative pressure on the oxygen outlet side using a vacuum pump or the like directly driven by an engine. Due to the configuration adopted, variable control of the partial pressure value itself independent of the engine speed is not necessarily easy, and as a general rule, the oxygen supply amount is determined according to the drive capacity specified by the engine speed. Become.

Therefore, when the engine speed rises above a predetermined value,
The partial pressure ratio between the oxygen-enriched membrane interface portions also increases accordingly. As a result, the amount of oxygen permeation increases, and in some cases there is a problem in that the oxygen concentration in the vehicle interior becomes too high than necessary.

(Means for Achieving the Object) The present invention was made with the aim of solving the above problems, and includes an air supply path on one side of the oxygen enrichment membrane and an oxygen outlet path on the other side. In addition, a partial pressure difference forming means for forming a predetermined partial pressure difference between the meat interface portions of the oxygen enriched membrane is provided, and a partial pressure difference forming means is provided for forming a predetermined partial pressure difference between the meat interface portions of the oxygen enriched membrane formed by the partial pressure difference forming means. An air conditioner for a vehicle that generates oxygen-enriched air to be supplied into a vehicle interior by permeating oxygen in the air supply road side supply air through the oxygen enrichment membrane to the oxygen outlet road side according to the partial pressure difference. A partial pressure difference regulating means is provided for regulating the partial pressure difference between the two surfaces 3 of the oxygen enrichment membrane, which is formed by the partial pressure difference forming means, to a predetermined value or less.

(Function) According to the above means, since it becomes possible to regulate the partial pressure difference to a predetermined value or less using the partial pressure difference regulating means, it becomes possible to control the upper limit of the oxygen concentration in the vehicle interior, and complex control means such as feedback control become possible. This makes it possible to easily prevent the oxygen concentration from rising too high without using.

(Embodiment) FIG. 1 shows a vehicle air conditioner according to an embodiment of the present invention, which is equipped with an oxygen enrichment function.

The air conditioner first includes a cooling system device consisting of a compressor 10, a condenser 111, an evaporator 12, etc., which are interconnected by a refrigerant pipe 14, and a hot water pipe (engine cooling water). A heating system device consisting of a hot water valve 20, a heater core 21, etc., interconnected by a hot water valve 20 (connected to piping) 13, a blower unit 30 for taking in outside air, an inside/outside air switching motor 31 for outside air ventilation and inside air circulation, and a blower. A ventilation system device consisting of a duct 32, etc., and an air conditioning temperature setting device 4
1, 42, an operation system device 40 consisting of various operation switches 43 to 50, etc., an air conditioning control unit 500 having various air conditioning control functions formed by a microcomputer, and an outside temperature sensor 5! , an internal temperature sensor 52, a water temperature sensor 53, a duct internal temperature sensor 54, an in-vehicle oxygen sensor 3, various control motors (mode switching motor 61, air mix damper control motor 62), etc.
Oxygen concentrator 70, vacuum pump 71. Air filter 72
, a blower motor 73, a duct 74 for supplying oxygen into the vehicle interior
It consists of an oxygen enrichment device and an oxygen enrichment device.

The evaporator 12 of the cooling system device and the heater core 21 of the heating system device are installed, for example, in a cooling/heating path unit case 6.7 provided below the dash panel, and are installed in a duct. The respective unit cases 6 and 7 are connected to each other via the portion 5 in a communicating state. A blower duct 32 of the blower unit 30 of the blower system is also connected to the unit case 6 side. Further, on the unit case 7 side, there is a heat duct 15 for heating and a vent duct 16 for ventilation and cooling.
are provided for each. Further, reference numeral 17 is rotatably pivotally attached to one end of the heater core 21 and located within the duct portion 5, and includes a passage from the duct side that passes through the heater core 21 and a passage that bypasses the heater core 21. , and a branch passage that together form both passages.The opening of the air mix damper 17 is controlled by the control motor 62, and the actual opening is controlled by a potentiometer. 63, and the detected value is input to the air conditioning control unit 500.

Further, reference numeral 66 is an opening/closing damper for the heat duct 15, and 67 is an opening/closing damper for the defroster 18, and the opening/closing portions of both opening/closing dampers 66, 67 are interlocked with each other in an inversely proportional opening degree. Note that the reference numeral 19 is a radiator.

On the other hand, the oxygen concentrator 70 on the oxygen enrichment device side is
For example, an oxygen-enriched film 82 formed of a polycarbonate-silicon copolymer is placed inside the hollow casing 81 as a partition wall 83.8.
The air intake port 84 side of the hollow housing 81 is connected to the main duct 75 for air intake in which the blower motor 73 and air filter 72 are interposed. At the same time, the oxygen permeation side space between the partition walls 83 and 83 in the hollow casing 81 is connected to the suction side of the vacuum pump 71 from the oxygen extraction lower part through the oxygen derivation duct 77. Further, one end of the oxygen supply duct 74 into the vehicle interior is connected to the discharge side of the vacuum pump 71.

The vacuum pump 71 is a compressor lO of the cooling system.
It is also driven by the engine E of the vehicle.

The vacuum pump 71 includes the oxygen enriched membrane 82,
A partial pressure difference (differential pressure) state is formed between the air supply side interface part and the oxygen extraction interface part of 82..., and the permeated oxygen is supplied into the vehicle interior.

The oxygen enrichment membranes 82, 82, . . . are non-porous amorphous polymer membranes, and when the vacuum pump 71 is driven, the interface on the permeation side is exposed to a predetermined negative pressure state, while On the other hand,
The interface portion on the air supply side is exposed to a positive pressure state equal to or higher than atmospheric pressure due to the air blowing pressure from the blower motor 73 described above. As a result, oxygen molecules mainly permeate from the high pressure side to the low pressure side between the interface parts of the oxygen enrichment membranes 82, 82, . . . in response to a partial pressure difference of a predetermined value or more. This permeation specifically occurs through a combination of dissolution and diffusion.

That is, as is well known, when air comes into contact with the surface of the amorphous polymer membrane, oxygen and nitrogen molecules in the air (note that the argon component is ignored due to its small proportion) are first absorbed by the oxygen-enriching membrane 82. It adsorbs on the surface and then dissolves into the interior of the oxygen-enriched membrane 82 due to molecular movement, resulting in a dissolving action. The oxygen and nitrogen molecules that have entered the oxygen-enriched film 82 due to the dissolution action further move inside the line film 82.

−8= That is, a diffusion effect occurs, and the gas eventually desorbs and exits from the permeation side (low pressure side) of the oxygen enrichment membrane 82, and the series of these effects causes a gas molecule permeation phenomenon as a whole.

In this case, the permeation amount of oxygen and nitrogen gas molecules is expressed by the following equation.

Therefore, in the case of a specific oxygen enrichment module, if the operating conditions of the vacuum pump 71 and blower motor 73 of the above embodiment are kept constant, the amount of permeation of each gas molecule is determined by the permeation coefficient unique to each gas molecule and the time (when the permeation is possible). (time to maintain).

The above-mentioned permeability coefficient is, of course, determined by the composition of the above-mentioned oxygen enrichment membrane 82, but for example, in the case of the polycarbonate-silicon copolymer of this embodiment, the permeability coefficient of the above-mentioned oxygen molecules is generally determined. It is much larger (about 3 times) than the permeability coefficient of nitrogen molecules.

Therefore, the amount of transmission naturally increases. In addition, to explain the relationship between these in more detail, the above transmission coefficient is
It is determined by the product of the solubility coefficient, which determines the size of the above-mentioned dissolution effect, and the diffusion coefficient, which determines the size of the diffusion effect, and the latter diffusion coefficient is determined by the van der Waals diameter (molecular diameter) of the gas molecule. It is known that it will be decided. In the case of the above-mentioned oxygen molecules, first of all, the solubility coefficient is larger than that of nitrogen molecules, while the van der Waals diameter of the molecule is small, so the diffusion coefficient is large. Therefore, the transmission coefficient, which is the product of these, naturally also increases. As a result, the time required for permeation of nitrogen molecules is much longer than that of oxygen molecules, and the air flow rate between the oxygen-enriching membranes 82, 82, etc. is based on, for example, the solubility coefficient of oxygen molecules. If the setting is made to obtain an effective permeation time, the oxygen molecules will dissolve first while the nitrogen molecules are hardly dissolved, and the adsorbing nitrogen molecules will be swept away to the discharge lower 8 side. Eventually, only oxygen molecules will be able to pass through. Therefore, according to the oxygen concentrator 70 having such a configuration, the oxygen concentration (%) taken out to the passenger compartment side basically depends on the oxygen enrichment membrane 82.8 as shown in FIG.
2. Air supply side pressure Pi and oxygen extraction side pressure Po
It is determined by the partial pressure ratio (Po/Pi).

On the other hand, the oxygen derivation duct 77 connecting the vacuum pump 71 to the oxygen concentrator 70 is provided with an outside air introduction duct 88, and the outside air introduction duct 88 also has a A negative pressure control valve 89 consisting of a valve is provided. The negative pressure control valve 89 is automatically opened/closed when the suction negative pressure of the vacuum pump 71 exceeds a predetermined regulation value (see Fig. 3), regardless of the control signal from the air conditioning control unit 500. When the valve is opened, outside air is introduced into the oxygen deriving duct 77, and the oxygen enrichment membranes 82, 82,
By lowering the suction negative pressure of the vacuum pump 71 (this becomes the negative pressure at the oxygen outlet side interface of the oxygen concentrator 70), the partial pressure ratio in the graph of FIG. acts to reduce the amount of oxygen supplied to the body.

As a result, the oxygen concentration in the vehicle compartment can always be restricted to a certain value or less even when the rotational speed of the vacuum pump 71 increases significantly due to an increase in the engine speed by 1. This prevents the oxygen concentration within the vehicle from becoming excessively high. Furthermore, in this case, it is sufficient to simply provide a negative pressure control valve 89 with a relief function to regulate the upper limit of the partial pressure ratio acting on the oxygen enrichment membranes 82, 82, so for example, an oxygen concentration sensor may be provided in the vehicle interior, If a configuration is adopted in which the driving state of the vacuum pump 71 is feedback-controlled in accordance with the detected oxygen concentration value, the structure can be significantly simplified.

(Effects of the Invention) As explained above, the present invention provides an air supply path on one side of the oxygen enrichment membrane and an oxygen outlet path on the other side, and further provides an air supply path on one side of the oxygen enrichment membrane and an oxygen outlet path on the other side. A partial pressure difference forming means for forming a predetermined partial pressure difference between the interface parts is provided, and the pressure difference in the air supplied to the air supply path side is adjusted according to the partial pressure difference between both interface parts of the oxygen enriched membrane formed by the partial pressure difference forming means. In the air conditioner for a vehicle, the air conditioner is configured to generate oxygen-enriched air to be supplied into a vehicle interior by permeating oxygen through the oxygen-enriching membrane to the oxygen outlet path side, wherein the oxygen-enriched air formed by the partial pressure difference forming means The present invention is characterized in that a partial pressure difference regulating means is provided for regulating the partial pressure difference between the oxygen derivation side interface portions to a predetermined value or less.

Therefore, according to the present invention, since the partial pressure difference regulating means can regulate the partial pressure difference to a predetermined value or less, it is possible to control the upper limit of the oxygen concentration in the vehicle interior, and it is not necessary to use complicated control means such as feedback control. This makes it easy to prevent the oxygen concentration from rising too high.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a vehicle air conditioner system according to an embodiment of the present invention using an oxygen enrichment membrane, and Fig. 2 shows the partial pressure ratio and oxygen separation concentration of the oxygen concentrator in the same embodiment. FIG. 3 is a graph showing the relationship between the oxygen concentration and the negative pressure value on the oxygen outlet side 4, which is the oxygen concentration determining factor, in the apparatus according to the embodiment of the present invention using the above-mentioned oxygen enrichment membrane. It is. 500... Air conditioning control unit 70...
... Oxygen concentrator 71 ... Vacuum pump 73 ... Blower motor 74 ... Oxygen supply duct 75 ... Air intake main duct 77 ...
・Oxygen derivation duct 81...Hollow casing 82...Oxygen enrichment membrane 88...Outside air introduction duct

Claims (1)

[Claims] 1. An air supply path is provided on one side of the oxygen enrichment membrane, and an oxygen outlet path is provided on the other side, and a partial pressure difference forming means is further provided for forming a predetermined partial pressure difference between both interface portions of the oxygen enrichment membrane. , allowing oxygen in the air supplied to the air supply path side to permeate through the oxygen enrichment membrane to the oxygen outlet path side in accordance with the partial pressure difference between the interface portions of the oxygen enrichment membrane formed by the partial pressure difference forming means; In a vehicle air conditioner that generates oxygen-enriched air to be supplied into a vehicle interior, the partial pressure difference between both interface portions of the oxygen-enriching membrane formed by the partial pressure difference forming means is reduced to a predetermined value or less. An air conditioner for a vehicle, characterized in that it is provided with partial pressure difference regulating means.