JPH07101234A - Oxygen-rich air generating device for automobile - Google Patents

Abstract

PURPOSE:To keep the air conditioning in a cabin at a constantly comfortable level by automatically switching the oxygen-rich mode and the carbon dioxide removing mode according to the air supply mode and the car speed. CONSTITUTION:A microcomputer 21 judges thc car speed based on the car speed signal to be outputted from a car speed sensor 22, and also judges whether the air-supply mode of an air-conditioner 20 is the ventilation mode to supply the outside air or the inside air circulating mode to supply the air in the cabin The microcomputer 21 controls the ON/OFF of a mode switching switch 18 to switch the oxygen-rich mode and the carbon dioxide removing mode according to the air supply mode and the car speed by implementing the control program to be stored in a built-in ROM. This constitution can keep the condition of the air in the cabin at a constantly comfortable level irrespective of the air supply mode and the car speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle oxygen-enriched air generator for supplying oxygen-enriched air having an increased oxygen concentration into a vehicle compartment.

[0002]

2. Description of the Related Art Recently, it has been considered to mount an oxygen-enriched air generator on an automobile in order to prevent a decrease in the oxygen concentration in the air inside the vehicle and maintain the comfort of driving.
This oxygen-enriched air generator is provided with an adsorption tank containing an adsorbent such as zeolite that adsorbs nitrogen in the air, and air is sent by a compressor into the adsorption tank to reduce the nitrogen concentration in the air and oxygen. Enriched air is generated and this oxygen-enriched air is supplied into the passenger compartment.

[0003]

By the way, as an air environment that affects comfort, there is a carbon dioxide concentration in addition to an oxygen concentration. To confirm this, the relationship between the air environment (oxygen concentration, carbon dioxide concentration) and the human fatigue reduction rate was examined, and the results shown in FIG. 6 were obtained. In FIG. 6, the region I is a region where the fatigue reduction rate is high and the user feels comfortable due to the high oxygen concentration / low carbon dioxide concentration.
Is a region in which the oxygen concentration is slightly low, but the fatigue reduction rate (comfort) that is almost the same as in region I can be secured by reducing the carbon dioxide concentration. It is an area of low comfort.

As is clear from this relationship, even if the oxygen concentration is high, if the carbon dioxide concentration is high, the fatigue reduction rate (comfort) will be significantly reduced. Therefore, in order to maintain comfort, it is also necessary to lower the carbon dioxide concentration in addition to oxygen enrichment.

However, the above-mentioned conventional ones aim to improve the air environment only by enriching oxygen,
Since it is not configured to control the carbon dioxide concentration, sufficient comfort cannot be ensured.

Further, the oxygen concentration and the carbon dioxide concentration in the vehicle interior air also change depending on the intake mode of the air conditioner (air conditioner) mounted on the vehicle and the vehicle speed. That is,
As shown in FIG. 5, when the intake mode of the air conditioner is the ventilation mode in which the outside air is taken in, a large amount of fresh outside air can be introduced into the vehicle interior, so the oxygen concentration and the carbon dioxide concentration in the vehicle interior air can be reduced. Both can be kept at a comfortable level. However, when the intake mode of the air conditioner is the internal air circulation mode for sucking in the vehicle interior air, the ventilation volume of the vehicle interior air is very small at a vehicle speed of 20 km / h or less,
Both oxygen and carbon dioxide concentrations in the cabin air exceed the long-term safety limits of the US Department of Occupational Health, which makes passengers uncomfortable. In this state, even if the oxygen-enriched air is supplied to the passenger compartment, the occupant will feel discomfort because the carbon dioxide concentration in the passenger compartment air is high. However, even in this inside air circulation mode, as the vehicle speed increases, the amount of outside air that enters the vehicle interior increases. Therefore, as shown in FIG. 5, for example, at a vehicle speed of 60 km / h, the state of the air inside the vehicle interior is as described above. It can be maintained in almost the same good condition as in the ventilation mode.

From the above, in the case of an automobile, it is necessary to control the oxygen concentration and the carbon dioxide concentration in the air in the passenger compartment in consideration of both the intake mode of the air conditioner and the vehicle speed.
At present, even the technology for controlling the carbon dioxide concentration in the air inside the vehicle has not been developed.

The present invention has been made in consideration of the above circumstances, and its purpose is regardless of the intake mode or the vehicle speed.
An object of the present invention is to provide an oxygen-enriched air generator for a vehicle, which can always keep the state of the air in the vehicle compartment at a comfortable level.

[0009]

In order to achieve the above object, an automobile oxygen-enriched air generator of the present invention is provided with an adsorption tank containing an adsorbent for adsorbing nitrogen and carbon dioxide in the air, In the adsorption tank, air is sent by the air supply means to generate oxygen-enriched air, and the oxygen-enriched air is supplied into the vehicle compartment. Mode switching means for switching between an oxygen-enriched mode for producing purified air and a carbon dioxide removal mode for removing carbon dioxide in the air, and a ventilation mode for the intake mode of an air conditioner installed in a vehicle to inhale outside air Or an internal air circulation mode for inhaling the air in the passenger compartment, an intake mode determining means, a vehicle speed determining means for determining the vehicle speed, the intake mode determining means and the front The control means controls the operation of the mode switching means so as to switch between the oxygen enrichment mode and the carbon dioxide removal mode according to the intake mode and the vehicle speed determined by the vehicle speed determination means. It is a thing.

[0010]

In advance, the intake mode determination means determines whether the intake mode of the air conditioner is the ventilation mode or the inside air circulation mode, and the vehicle speed determination means determines the vehicle speed. Based on these determination results, the control means controls the operation of the mode switching means, and the operating pressure of the adsorption tank (hereinafter referred to as “swing pressure”) is switched in accordance with the intake mode and the vehicle speed, whereby the oxygen enrichment mode and the oxidation mode are changed. Switch to and from carbon removal mode.

In this case, carbon dioxide is
Since the adsorbent (for example, zeolite) in the adsorption tank has a strong selective adsorption property to polar molecules, it has a characteristic that the adsorption amount of carbon dioxide per unit time increases as the flow rate of air passing through the adsorption tank increases. By utilizing this characteristic, in the carbon dioxide removal mode, the swing pressure is made lower than that in the oxygen enrichment mode to increase the flow rate of air passing through the adsorption tank and efficiently adsorb carbon dioxide in the air. Then, the carbon dioxide concentration in the air is reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, a schematic configuration of the entire oxygen-enriched air generator for a vehicle will be described with reference to FIG. In both of the oxygen enrichment mode and the carbon dioxide removal mode, the indoor air passes through the solenoid valve EV1 and the compressor 1 serving as an air feeding means.
Inhaled to 1. The air discharged from the compressor 11 flows into the adsorption tank 12 through the electromagnetic valve EV2. In the adsorption tank 12, an adsorbent such as zeolite (not shown) that adsorbs nitrogen and carbon dioxide in the air
Is housed. A low pressure circuit 14 having a solenoid valve EV3 and a check valve 13 and a high pressure circuit 17 having an orifice 15 and a check valve 16 are connected in parallel to the air flow path on the outlet side of the adsorption tank 12.

In this case, in the oxygen enrichment mode, by closing (turning off) the solenoid valve EV3 of the low pressure circuit 14, the flow passage resistance of the air flow path on the outlet side of the adsorption tank 12 is increased to increase the adsorption tank 12. The internal pressure (swing pressure) is switched to a high pressure (for example, 50 KPa) suitable for nitrogen adsorption, and the oxygen-enriched air flowing out from the adsorption tank 12 is fed to
As indicated by a solid arrow in FIG.
5 → Outflow through check valve 16). This high voltage circuit 1
The outlet side of 7 is connected to a driver spot nozzle (not shown) attached to the backrest (not shown) of the driver's seat, and oxygen-enriched air flowing out from the high-pressure circuit 17 is discharged from the driver spot nozzle. It is designed to be spotted toward the driver's face.

On the other hand, in the carbon dioxide removal mode, the solenoid valve EV3 of the low pressure circuit 14 is opened (turned on) to reduce the flow path resistance of the air flow path on the outlet side of the adsorption tank 12 and to reduce the swing pressure. The air having a low carbon dioxide concentration flowing out from the adsorption tank 12 is switched to a low pressure suitable for carbon adsorption (for example, 8 KPa), and the low pressure circuit 14 (solenoid valve EV3 → return valve) is operated as shown by the one-dot chain arrow in FIG. Drain through valve 13). The outlet side of the low-voltage circuit 14 has an air conditioner 20 (see FIG. 3) installed in the automobile.
The air having a low carbon dioxide concentration flowing out of the low-pressure circuit 14 is connected to a blower duct (not shown) of the vehicle and is mixed with the conditioned air flowing in the blower duct to be discharged from the dashboard outlet (not shown) to the passenger compartment. It is supposed to be blown out to.

In any of the above-described oxygen enrichment mode and carbon dioxide removal mode, during the operation of the mode, nitrogen or carbon dioxide molecules adsorbed by the adsorbent in the adsorption tank 12 are removed to obtain an adsorption capacity. The operation in the regeneration mode for recovering the temperature is executed intermittently. In this regeneration mode, the solenoid valves EV1 and EV2 are closed (OFF) and the solenoid valves EV4 and EV5 are opened (ON).
Then, the compressor 11 is operated. As a result, the air remaining in the adsorption tank 12 is discharged to the outside of the vehicle cabin through the path of the electromagnetic valve EV4 → the compressor 11 → the electromagnetic valve EV5 as shown by the dotted arrow in FIG. Is reduced to, for example, about -80 KPa to remove nitrogen and carbon dioxide molecules adsorbed by the adsorbent in the adsorption tank 12 and recover the adsorption capacity. The operation (opening), the operation time, the operation pressure, and the air flow rate of the solenoid valves EV1 to EV5 in each mode described above are set as shown in FIG.

Next, the structure of the electric circuit will be described with reference to FIG. The mode changeover switch 18 functions as a mode changeover means for changing over between the oxygen enrichment mode and the carbon dioxide removing mode, and the first relay coil RL1 is connected in series to the mode changeover switch 18. When the mode changeover switch 18 is off, the oxygen enrichment mode is set, the normally open relay switch RL1a is maintained in the off state, and the solenoid valve EV3 is maintained in the closed state. After that, when the mode changeover switch 18 is turned on, the first relay coil RL1 is energized, the normally open relay switch RL1a is turned on, the solenoid valve EV3 is opened (turned on), and the carbon dioxide removal mode is set. Can be switched.

On the other hand, the main switch 19 is connected to the second relay coil RL2. When the main switch 19 is turned on, the second relay coil RL2 is energized and the relay switch RL2a is turned on. As a result, the operation of the compressor 11 is started and the first relay timer RLT1 and solenoid valves EV1 and EV2 are energized via the normally closed relay switch RL3a. The first relay timer RLT1 starts timing operation at the same time as energization, and after a predetermined time elapses, the relay switch RLT1.
Switch 1a on. This relay switch RLT1
When a is turned on, the third relay coil RL3 is energized via the normally closed relay switch RLT2a, the normally closed relay switch RL3a is turned off, and the electromagnetic valve EV1,
The EV2 is turned off, the relay switch RL3b is turned on, and the solenoid valves EV4 and EV5 are energized via the relay switch RL3b and the normally closed relay switch RLT2a to start the deaeration mode operation.

During the operation in the deaeration mode, the second relay timer RLT2 is energized via the relay switch RL3b. The second relay timer RLT2 counts the operation time of the deaeration mode (deaeration time), and turns off the normally closed relay switch RLT2a after a predetermined time has elapsed. As a result, the third relay coil RL3 and the solenoid valves EV4 and EV5 are turned off, and the normally-closed relay switch RL3a is returned to the on state, so that the solenoid valves EV1 and E5.
V2 is turned on, and the operation is performed in either the carbon dioxide removal mode or the oxygen enrichment mode set by the mode changeover switch 18.

Turning on / off of the mode changeover switch 18 is controlled by a microcomputer 21. This microcomputer 21 has a vehicle speed sensor 22.
It functions as a vehicle speed determination unit that determines the vehicle speed based on the vehicle speed signal output from the vehicle, and whether the intake mode of the air conditioner 20 is a ventilation mode for inhaling outside air or an inside air circulation mode for inhaling air in the vehicle compartment. It also functions as intake mode determination means for determining. Further, the microcomputer 21 executes the control program of FIG. 4 stored in a built-in ROM (not shown) to switch between the oxygen enrichment mode and the carbon dioxide removal mode according to the intake mode and the vehicle speed. Mode selector switch 1 to switch
It also functions as a control means for controlling ON / OFF of No. 8.

By the way, as shown in FIG.
When the intake mode of 0 is the ventilation mode, a large amount of fresh outside air can be introduced into the vehicle interior, so that both the oxygen concentration and the carbon dioxide concentration of the vehicle interior air can be maintained at comfortable levels. However, when the intake mode is the internal air circulation mode, for example, at a vehicle speed of 20 km / h or less, since the ventilation volume of the vehicle interior air is very small, both the oxygen concentration and the carbon dioxide concentration in the vehicle interior air become Exceeding the long-term safety limit of the Occupational Health Bureau, occupants will feel discomfort. In this state, even if the oxygen-enriched air is supplied to the passenger compartment, the occupant will feel discomfort because the carbon dioxide concentration in the passenger compartment air is high. However, even in this inside air circulation mode, as the vehicle speed increases, the amount of outside air that enters the vehicle interior increases, so as shown in FIG.
At a vehicle speed of 0 km / h, the state of the air inside the vehicle interior can be maintained in a good state that is almost the same as in the ventilation mode described above.

In consideration of such a situation, in the present embodiment, the microcomputer 21 sets the oxygen enrichment mode and the carbon dioxide removal mode in accordance with the intake mode and the vehicle speed as follows by the control program shown in FIG. Switch.
First, in step S1, it is determined whether the vehicle speed exceeds 20 km / h. When the vehicle speed exceeds 20 km / h, the ventilation volume in the vehicle compartment is large and the air quality control effect is small even when operating in the carbon dioxide removal mode. Therefore, the process proceeds to step S4, and oxygen enrichment is performed. Switch to mode. In this oxygen enrichment mode, the solenoid valve E of the low pressure circuit 14 is
By closing (off) V3, the pressure (swing pressure) in the adsorption tank 12 is switched to a high pressure suitable for adsorbing nitrogen,
The oxygen-enriched air flowing out of the adsorption tank 12 is supplied to the high pressure circuit 17 (orifice 15 →
It flows through the check valve 16) and is blown out in spots from the driver spot nozzle toward the driver's face. Here, the reason why the oxygen-enriched air is blown out in spots is that when the vehicle speed exceeds 20 km / h, the oxygen-enriched air is mixed with the conditioned air because the ventilation volume in the vehicle compartment is large. This is because blowing out from the air outlet (not shown) of the dashboard causes the oxygen-enriched air to diffuse and the air quality control effect to decrease.

On the other hand, if the vehicle speed is 20 km / h or less,
From step S1 to step S2, the air conditioner 20
It is determined whether the intake mode of is the ventilation mode or the internal air circulation mode. In the ventilation mode, since the ventilation volume in the passenger compartment is large, the process proceeds to step S4 to perform the oxygen enrichment mode operation as in the case where the vehicle speed exceeds 20 km / h. For example, since the ventilation volume in the passenger compartment is low and the carbon dioxide concentration in the passenger compartment air is high, the process proceeds to step S3, and the mode is switched to the carbon dioxide removal mode. In this carbon dioxide removal mode, the solenoid valve EV3 of the low pressure circuit 14 is opened (turned on) to switch the swing pressure to a low pressure suitable for adsorption of carbon dioxide, and the air with a low carbon dioxide concentration flowing out from the adsorption tank 12 is removed. , Figure 1
As indicated by the one-dot chain line arrow, the low pressure circuit 14 (solenoid valve E
It is made to flow out through V3 → check valve 13), mixed with the conditioned air flowing in the air duct of the air conditioner 20, and blown out into the vehicle compartment from the air outlet (not shown) of the dashboard. This reduces the carbon dioxide concentration in the cabin air,
Stay comfortable.

According to the present embodiment described above, the oxygen enrichment mode and the carbon dioxide removal mode are appropriately switched depending on the intake mode of the air conditioner 20 and the vehicle speed in consideration of the ventilation amount in the vehicle interior. Therefore, regardless of the intake mode or the vehicle speed, the state of the air inside the vehicle can be always maintained at a comfortable level. Moreover, since the switching between the oxygen enrichment mode and the carbon dioxide removal mode is controlled by the intake mode and the vehicle speed, it is not necessary to provide a costly gas sensor, and the demand for cost reduction can be satisfied.

In this embodiment, the vehicle speed at which the oxygen enrichment mode is switched to the carbon dioxide removal mode is set to 20 km / h when the intake mode is the internal air circulation mode. However, this is appropriately set according to the type of vehicle. It goes without saying that you can change it. Further, in the present embodiment, the driver spot nozzle that blows out the oxygen-enriched air is provided, but the oxygen-enriched air may be blown out through the outlet of the dashboard.

Besides, the present invention is not limited to the above-mentioned embodiment, and for example, the air feeding means may be the compressor 11
To a blower, a high-pressure circuit 17 may be provided with a solenoid valve, and the swing pressure may be appropriately changed according to the size and structure of the adsorption tank 12. It goes without saying that you can do it.

[0026]

As is apparent from the above description, according to the present invention, the oxygen enrichment mode and the carbon dioxide removal mode are automatically switched according to the intake mode and the vehicle speed. Regardless of the vehicle speed, the air condition inside the vehicle can be maintained at a comfortable level. Moreover, since the switching between the oxygen enrichment mode and the carbon dioxide removal mode is controlled by the intake mode and the vehicle speed, it is not necessary to provide a costly gas sensor, and the demand for cost reduction can be satisfied.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between each mode and operation of each solenoid valve, operating time, operating pressure, and air flow rate.

FIG. 3 is an electric circuit diagram showing an electric configuration of the entire oxygen-enriched air generator for an automobile.

FIG. 4 is a flowchart showing the flow of control.

FIG. 5 is a diagram showing the relationship among intake mode, vehicle speed, oxygen concentration, and carbon dioxide concentration.

FIG. 6 is a diagram showing a relationship between an air environment and a fatigue reduction rate.

[Explanation of symbols]

11 ... Compressor (air supply means), 12 ... Adsorption tank,
13 ... Check valve, 14 ... Low pressure circuit, 15 ... Orifice, 1
7 ... High-pressure circuit, 16 ... Check valve, 18 ... Mode changeover switch (mode changeover means), 19 ... Main switch, 21 ...
Microcomputer (control means, intake mode determination means, vehicle speed determination means), 22 ... Vehicle speed sensor (vehicle speed determination means), EV1 to EV5 ... Electromagnetic valves (mode switching means).

Claims (1)

[Claims] 1. An adsorption tank containing an adsorbent for adsorbing nitrogen and carbon dioxide in air is provided, and air is sent to the adsorption tank by an air supply means to generate oxygen-enriched air.
In an oxygen-enriched air generator for a vehicle adapted to supply this oxygen-enriched air to a vehicle compartment, an oxygen-enriched mode for generating oxygen-enriched air by switching the operating pressure of the adsorption tank, and Mode switching means for switching between the carbon dioxide removal mode for removing the carbon dioxide of the vehicle and the intake mode of the air conditioner installed in the vehicle is the ventilation mode for inhaling the outside air or the inside air circulation for inhaling the air inside the vehicle Intake mode determination means for determining whether the vehicle is in a mode, vehicle speed determination means for determining the vehicle speed, the intake mode determined by the intake mode determination means and the vehicle speed determination means, and the oxygen enrichment mode according to the vehicle speed And a control means for controlling the operation of the mode switching means so as to switch between the carbon dioxide removal mode and the automatic mode. Oxygen-rich air generator for vehicles.