JP2001206707A - Nitrogen filling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a nitrogen filling device for filling gaseous nitrogen small- sized. SOLUTION: The nitrogen filling device 10 is constituted integrally by containing an air filter 12 for removing dust from compressed air supplied from the outside, a micro mist separator 14 for removing oil mist from the compressed air, from which the dust is removed, a regulator 16 for controlling the compressed air, from which the oil mist is removed, to a fixed pressure, a membrane dryer 18 for dehumidifying the compressed air controlled to the fixed pressure, a nitrogen separator 20 for removing oxygen from the dehumidified compressed air and generating gaseous nitrogen having a prescribed concentration, a buffer tank 24 for storing the gaseous nitrogen generated in the nitrogen separator 20, a gaseous nitrogen taking-out port 50 for taking out the gaseous nitrogen stored in the buffer tank 24 to outside, an O2 sensor 44, a control unit 46 and a digital display meter 48 (there 44, 46 and 48 and used for detecting the concentration of gaseous nitrogen stored in the buffer tank 24).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nitrogen filling apparatus for filling a tire or the like with nitrogen gas, and more particularly, to a technique for promoting miniaturization of the apparatus.

[0002]

2. Description of the Related Art In recent years, a technique has been proposed in which tires of automobiles and the like are filled with nitrogen gas instead of air to improve running stability, safety and comfort of the automobile. That is, when the tire is filled with air, since the air passes through the rubber of the tire and gradually escapes, the air pressure of the tire is reduced, and there is a risk that fuel efficiency may deteriorate or burst. For this reason,
Nitrogen gas, which is less permeable to the rubber of the tire than air, was filled into the tire to avoid such danger.

[0003]

However, since the filling of a tire with nitrogen gas is usually performed by a cylinder filled with nitrogen gas, it is necessary to fill a large number of tires with nitrogen gas. Requires a large-capacity cylinder, which inevitably increases the size of the nitrogen filling device. Further, when the nitrogen gas filled in the cylinder is used up, it must be replaced with a new cylinder, and there are also problems such as an increase in the number of steps involved in replacing the cylinder and an increase in cost associated with storing the replacement cylinder. For this reason, it is economically difficult to equip individual gas stations with a nitrogen filling device, and this has been a barrier to widespread filling of tires with nitrogen gas.

On the other hand, a technique of separating a specific gas from compressed air by a gas separation membrane is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-314.
No. 539 and Japanese Patent Application Laid-Open No. H11-333237, the devices used in these techniques are still large and cannot be used easily at individual gas stations.

The present invention has been made in view of the above-mentioned conventional problems, and has a small and simple structure so that high-concentration nitrogen gas can be easily generated from compressed air. It is an object of the present invention to provide a nitrogen filling device that can be used for a fuel cell.

[0006]

SUMMARY OF THE INVENTION Therefore, the invention according to claim 1 includes a dust removing means for removing dust from compressed air, and an oil mist removing means for removing oil mist from compressed air from which dust has been removed. Pressure regulating means for regulating the compressed air from which the oil mist has been removed to a predetermined pressure; nitrogen gas generating means for removing oxygen from the compressed air regulated to the predetermined pressure to generate nitrogen gas of a predetermined concentration; Storage means for storing the nitrogen gas generated by the nitrogen gas generation means,
And a nitrogen gas extracting means for extracting the nitrogen gas stored in the storage means to the outside.

According to this configuration, the compressed air from which dust and oil mist have been removed by the dust removing means and the oil mist removing means is regulated to a predetermined pressure by the pressure regulating means. The compressed air adjusted to a predetermined pressure is introduced into a nitrogen gas generating means, and a predetermined concentration of nitrogen gas is generated. Then, the generated nitrogen gas is temporarily stored by the storage means, and is taken out to the outside by the nitrogen gas take-out means as needed. Therefore, a compact and simple configuration of the nitrogen filling apparatus is realized by integrally configuring these units. In addition, if the capacity of the storage means is set appropriately, that is, set to a predetermined capacity, nitrogen can be charged to many tires and the like even with a small device configuration, and the nitrogen charging efficiency is improved.

According to a second aspect of the present invention, there is provided a configuration including a concentration detecting means for detecting the concentration of nitrogen gas stored in the storage means, and a concentration displaying means for displaying the detected concentration of nitrogen gas. There is a feature.

According to this configuration, if the concentration of the nitrogen gas stored in the storage means is confirmed, for example, the concentration of the nitrogen gas to be charged into the tire can be maintained substantially constant, and the nitrogen gas is charged by the nitrogen charging device. It is possible to guarantee the quality of nitrogen gas.

According to a third aspect of the present invention, the concentration detecting means detects the concentration of oxygen contained in the nitrogen gas, and calculates the nitrogen gas concentration based on the detected oxygen concentration. And a density calculating means.

According to this configuration, since the concentration of nitrogen gas is detected using the oxygen concentration detecting means such as a general O ₂ sensor, it is possible to reduce the cost for detecting the concentration of nitrogen gas. .

The invention according to claim 4 is characterized in that a dehumidifying means for dehumidifying compressed air adjusted to a predetermined pressure is interposed between the pressure adjusting means and the nitrogen gas generating means. And

According to this configuration, for example, even if the compressed air supplied from the outside to the nitrogen filling device is not dehumidified, the dehumidified compressed air is supplied to the nitrogen gas generating means. The concentration of the nitrogen gas generated thereby is further improved.

According to a fifth aspect of the present invention, there is provided a nitrogen gas releasing means for releasing nitrogen gas generated by the nitrogen gas generating means into the atmosphere, and a predetermined time after the nitrogen gas generation is started by the nitrogen gas generating means. And a nitrogen gas release control means for releasing nitrogen gas into the atmosphere by the nitrogen gas release means.

According to this configuration, the nitrogen gas is released into the atmosphere by the nitrogen gas releasing means for a predetermined time after the generation of the nitrogen gas by the nitrogen gas generating means is started.
Therefore, immediately after the startup in which the concentration of the nitrogen gas generated in the nitrogen gas generating means is low, the nitrogen gas is prevented from being stored in the storage means, and the concentration of the nitrogen gas is prevented from lowering.

The invention according to claim 6 is characterized in that the nitrogen gas extracting means has a configuration including a hose reel. According to such a configuration, when taking out the nitrogen gas stored in the storage means to the outside, if the hose stored in the hose reel is extended, for example, the filling of the tire with the nitrogen gas becomes easy. Further, when the removal of the nitrogen gas is stopped, the hose is wound around a hose reel and stored, so that the hose can be easily cleared.

[0017] The invention according to claim 7 is characterized in that the invention includes at least one set of moving wheels and a moving handle. According to such a configuration, when moving the nitrogen filling apparatus, the entire apparatus is tilted with the moving handle, so that the moving wheel can be moved with a small amount of labor. Therefore, even a single worker can install the nitrogen filling device, which contributes to the spread of the nitrogen filling device to gas stations, for example.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the attached drawings. FIG. 1 shows the overall configuration of a nitrogen filling apparatus according to the present invention.

The nitrogen filling device 10 includes an air filter 12
(Dust removing means) and the micro mist separator 14
(Oil mist removing means), regulator 16 (pressure adjusting means), and membrane dryer 18 (dehumidifying means)
, A nitrogen separator 20 (nitrogen gas generating means), a flow controller 22, and a buffer tank 24 (storage means)
And is comprised.

The membrane dryer 18 is an air dehumidifier which makes it possible to easily make supplied air in an ultra-dry state by utilizing the property of a special polymer membrane that water vapor is very easy to permeate and air is hard to permeate. It is. The peripheral wall of the membrane dryer 18 has a purge air inlet 18a for carrying out water vapor permeated through the special polymer membrane to the outside.
And an outlet 18b is opened. That is, the purge air introduced through the inlet 18a is humidified by the water vapor that has passed through the special polymer film, and is discharged from the outlet 18b to the outside. When the supplied compressed air has been dried in advance, an air dehumidifier such as the membrane dryer 18 is not necessarily required.

The nitrogen separator 20 allows oxygen to selectively permeate through the membrane while compressed air flows through the hollow fiber membrane as a nitrogen-enriched membrane. As a result, nitrogen-rich gas ( (Hereinafter referred to as "nitrogen gas"). The oxygen that has passed through the membrane is introduced from the outlet 20a to the inlet 18a of the membrane dryer 18 so as to be used as purge air for the membrane dryer 18.

The flow controller 22 includes a flow control valve 22a and a flow meter 22b.
The flow rate of the nitrogen gas is set in order to set the concentration of the nitrogen gas generated by the above. That is, since the nitrogen separator 20 has a characteristic that the nitrogen gas concentration changes according to the flow rate, for example, a flow rate at which a desired nitrogen gas concentration is obtained is set based on catalog data.

Between the regulator 16 and the membrane dryer 18, a direct acting two-port valve 26 which closes when not energized and opens when energized is interposed. On the downstream side of the nitrogen separator 20, the nitrogen gas generated by the nitrogen separator 20 is discharged to the outside (hereinafter referred to as “open position”) or introduced into the buffer tank 24 via the flow rate controller 22 (hereinafter referred to as “open position”). A direct-acting three-port valve 28 (nitrogen gas releasing means) for switching the “storage position” is interposed. A muffler 30 for reducing exhaust noise is attached to a port for discharging nitrogen gas to the outside. On the other hand, linear motion 3
Between the port valve 28 and the flow regulator 22, the nitrogen gas stored in the buffer tank 24 does not flow backward,
A check valve 32 is interposed.

The buffer tank 24 has a safety valve 3 that opens when the nitrogen gas in the tank exceeds a predetermined pressure.
4, a drain valve 36 for discharging the drain in the tank to the outside, and a pressure gauge 38 for detecting the nitrogen gas pressure in the tank.
And are attached. Further, in order to detect the concentration of nitrogen gas in the tank, an O ₂ sensor 44 is provided through a check valve 40 and a flow control valve 42.
(Oxygen concentration detecting means) is attached. O ₂ sensor 4
The output signal of No. 4, ie, the output signal corresponding to the oxygen concentration in the buffer tank 24, is input to the control unit 46 having a built-in microcomputer, and the nitrogen gas concentration (%) is calculated by a calculation process described later. And
The calculated nitrogen gas concentration is displayed on a digital indicator 48 (concentration display means).

The concentration detecting means is constituted by including the O ₂ sensor 44 and the control unit 46, and the concentration calculating means and the nitrogen gas release controlling means are realized by the control unit 46 as software.

Further, the buffer tank 24 is provided with at least one nitrogen gas outlet 50 (50a to 50c; nitrogen gas extracting means) for extracting the stored nitrogen gas to the outside. Therefore, by connecting the hose to the nitrogen gas outlet 50, the nitrogen gas can be extracted to the outside and, for example, the tire can be filled with the nitrogen gas.

Note that one end of the air ring may be connected to the nitrogen gas outlet 50 so that the hose can be extended and contracted from the air ring. In this case, the removal of the nitrogen gas becomes easy, and for example, the operation of filling the tire of the customer's automobile with the nitrogen gas at the gas station can be performed more quickly.

Further, if the capacity of the buffer tank 24 is set to an appropriate value (for example, a large capacity), it is possible to fill many tires with nitrogen gas even with a small device configuration, and the nitrogen filling efficiency can be improved. .

FIGS. 2 and 3 show the appearance of a nitrogen filling apparatus 10 in which such various devices are integrated. An unillustrated air hose is led out from an outlet 52a opened in the main body cover 52, and a tire flatter is attached to the tip thereof, for example. Further, the instrumentation panel 54 includes pushbutton switches 56 and 58 for starting and stopping the nitrogen filling device 10, and an operation and stop indicator lamp 60,
62 and a pressure gauge 38 for detecting the nitrogen gas pressure in the buffer tank 24 are attached.

Further, a set of wheels 64 (moving wheels) is attached to a lower portion and a rear portion of the nitrogen filling device 10.
A rotary adjuster 66 is attached to a lower part and a front part of the nitrogen filling device 10. Therefore, when installing the nitrogen filling device 10, by adjusting the length of the rotary adjuster 66, the nitrogen filling device 10 is installed substantially horizontally by the set of wheels 64 and the rotary adjuster 66. In addition, a handle 68 (a handle for movement) used when transporting the nitrogen filling device 10 is attached to the upper rear portion of the nitrogen filling device 10. That is, if the nitrogen filling device 10 is tilted backward with the handle 68, the nitrogen filling device 10 can be moved with a small amount of labor by a set of wheels 64.

In the vicinity of the wheel 64, a nitrogen filling device 1 is provided.
A stopper 70 is mounted to prevent the nitrogen filling device 10 from tilting more than necessary when transporting zero. next,
The operation of the nitrogen filling device 10 having such a configuration will be described.

First, in preparation for operation, a grounded 100
A power plug (not shown) is inserted into the V outlet, and a hose from the compressor is connected to a compressed air inlet (not shown) provided on the upstream side of the air filter 12.

When the start push button switch 56 of the instrument panel 54 is pressed, the operation indicator light 60 is turned on, and the energization of the direct acting two-port valve 26 is started to open the valve. Is switched to the open position.

Then, the compressed air supplied from outside is
Air filter 12 and micro mist separator 1
4 removes dust and oil mist, and a predetermined pressure (for example, 0.5 to 1.0MP
a, typically 0.7 MPa). The compressed air adjusted to a predetermined pressure is dehumidified by the membrane drier 18, oxygen is removed by the nitrogen separator 20 to become nitrogen gas, and is discharged to the outside via the direct-acting three-port valve 28 and the muffler 30.

Then, when a predetermined time (for example, one minute) elapses after the activation push button switch 56 is pressed, the direct acting three-port valve 28 is switched to the storage position. As described above, the nitrogen gas generated by the nitrogen separator 20 is discharged to the outside for a predetermined time from the start of the nitrogen filling device 10 because the concentration of the nitrogen gas is low immediately after the start and the concentration gradually increases. This is because the coming characteristics are considered. Therefore, introduction of a low-concentration nitrogen gas into the buffer tank 24 is prevented, and the concentration of the nitrogen gas can be kept substantially constant.

Here, the switching of the direct acting three-port valve 28 is performed as follows.
For example, the processing may be performed based on a timer provided in the control unit 46, and such processing corresponds to nitrogen gas release control means.

When the direct-acting three-port valve 28 is switched to the storage position, the nitrogen gas generated by the nitrogen separator 20 is stored in the buffer tank 24 via the direct-acting three-port valve 28, the check valve 32 and the flow regulator 22. Is done. The nitrogen gas stored in the buffer tank 24 is introduced into the O ₂ sensor 44 via the check valve 40 and the flow control valve 42, and the concentration of oxygen contained in the nitrogen gas is detected. Here, in order to detect the concentration of oxygen contained in the nitrogen gas in real time, the buffer tank 24 is always used.
The opening of the flow control valve 42 is adjusted so that a small amount of nitrogen gas is introduced into the O ₂ sensor 44 from the above.

The oxygen concentration detected by the O ₂ sensor 44 is converted by the control unit 46 into a nitrogen gas concentration. That is, since the concentration of nitrogen gas generated by the nitrogen separator 20 accurately represents the sum of the concentrations of components other than oxygen, the nitrogen gas concentration (%) = 100−the oxygen concentration (%) The nitrogen gas concentration is calculated.

The process for calculating the nitrogen gas concentration corresponds to the concentration calculating means. When the nitrogen gas pressure in the buffer tank 24 becomes 0.3 MPa or more, the tire can be filled with nitrogen gas using an air hose or the external tank can be filled with nitrogen gas using the nitrogen gas outlet 50. Becomes

Finally, when the work is completed, when the stop push button switch 58 of the instrumentation panel 54 is pressed, the energization to the direct acting two-port valve 26 is cut off and the valve is closed. Is switched to the open position, and the storage of the nitrogen gas in the buffer tank 24 is stopped. At this time, since a small amount of nitrogen gas is introduced into the O ₂ sensor 44 from the buffer tank 24 for detecting the nitrogen gas concentration, the pressure of the nitrogen gas in the buffer tank 24 gradually decreases.

According to the nitrogen filling apparatus 10 described above,
With a small and simple configuration as compared with the related art, it is possible to easily generate high-concentration nitrogen gas from compressed air. Therefore, in the future, even if it is common to fill the automobile tires with nitrogen gas from the viewpoint of safety, etc., for example,
It is possible to provide a nitrogen filling device in a limited space such as a gas station or a tire maintenance space, so that it is possible to easily respond to social demands.

[0042]

As described above, according to the first aspect of the present invention, it is possible to realize a small and simple nitrogen filling apparatus. For this reason, for example, it is possible to equip each gas station with a nitrogen filling device,
Even if it is common to fill a car tire with nitrogen gas, it can be easily handled. Further, if the capacity of the storage means is set to an appropriate value, that is, a predetermined capacity, nitrogen can be charged into many tires and the like even with a small device configuration, and nitrogen filling efficiency can be improved.

According to the second aspect of the present invention, by confirming the concentration of the nitrogen gas, it is possible to guarantee the quality of the nitrogen gas filled by the nitrogen filling device. Claim 3
According to the described invention, it is possible to reduce the cost for detecting the nitrogen gas concentration.

According to the invention described in claim 4, the nitrogen gas concentration can be further improved. According to the fifth aspect of the invention, immediately after the start-up in which the concentration of the nitrogen gas generated by the nitrogen gas generating means is low, the nitrogen gas is prevented from being stored in the storage means, and the concentration of the nitrogen gas is prevented from lowering. can do.

According to the sixth aspect of the present invention, it is possible to reduce the labor involved in extracting nitrogen gas. Claim 7
According to the described invention, even one worker can install the nitrogen filling device, which can contribute to the spread of the nitrogen filling device to gas stations, for example.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a nitrogen filling apparatus according to the present invention.

FIG. 2 is a front view showing the appearance of the nitrogen filling apparatus according to the present invention.

FIG. 3 is a side view of the above.

[Explanation of symbols]

10 nitrogen-filled apparatus 12 Air Filter 14 micro mist separator 16 regulator 18 membrane dryer 20 nitrogen separator 24 buffer tank 28 linear three-port valve 44 O ₂ sensor 46 control unit 48 the digital display meter 50 nitrogen gas outlet 64 wheel 68 handle

Claims (7)

[Claims] 1. Dust removing means for removing dust from compressed air, oil mist removing means for removing oil mist from compressed air from which dust has been removed, and regulating the compressed air from which oil mist has been removed to a predetermined pressure. Pressure adjusting means, nitrogen gas generating means for removing oxygen from compressed air adjusted to a predetermined pressure to generate nitrogen gas of a predetermined concentration, and storage means for storing nitrogen gas generated by the nitrogen gas generating means. And a nitrogen gas extracting means for extracting the nitrogen gas stored in the storage means to the outside. 2. The apparatus according to claim 1, further comprising: concentration detecting means for detecting the concentration of nitrogen gas stored in said storage means; and concentration displaying means for displaying the detected concentration of nitrogen gas. Nitrogen filling equipment. 3. An oxygen concentration detecting means for detecting a concentration of oxygen contained in nitrogen gas, a concentration calculating means for calculating a concentration of nitrogen gas based on the detected oxygen concentration, and The nitrogen filling apparatus according to claim 2, wherein the nitrogen filling apparatus has a configuration including: 4. The apparatus according to claim 1, wherein a dehumidifying means for dehumidifying the compressed air adjusted to a predetermined pressure is interposed between said pressure adjusting means and said nitrogen gas generating means. A nitrogen filling apparatus according to any one of the preceding claims. 5. A nitrogen gas discharging means for releasing nitrogen gas generated by said nitrogen gas generating means into the atmosphere, and said nitrogen gas being discharged for a predetermined time from the start of generation of nitrogen gas by said nitrogen gas generating means. The nitrogen filling apparatus according to any one of claims 1 to 4, comprising: nitrogen gas release control means for releasing nitrogen gas into the atmosphere by the release means. 6. The nitrogen filling apparatus according to claim 1, wherein said nitrogen gas take-out means includes a hose reel. 7. The nitrogen filling apparatus according to claim 1, wherein the nitrogen filling apparatus includes at least one set of moving wheels and a moving handle.