JP2563766B2 - Gas fuel gauge - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas fuel gauge for measuring the amount of gas remaining in a gas cylinder, which is consumed at a constant flow rate, and relates to oxygen in an oxygen cylinder used in a portable oxygen inhaler for home medical care. It can be used for measuring the remaining amount of gas, measuring the remaining amount of welding gas in automatic welding machines, and measuring the remaining amount of gas used in semiconductor manufacturing.

[0002]

BACKGROUND ART Conventionally, a device using a load cell has been used as a device for measuring the amount of gas remaining in a gas cylinder (Japanese Patent Laid-Open No. 3-9).
No. 4125, etc.) or a device using a Bourdon tube pressure gauge (see Japanese Patent Laid-Open No. 61-193041 etc.). The device using the former load cell, with the gas cylinder placed on the cylinder base, tilts this cylinder base to bring the corners of the cylinder base into contact with the load cell,
At this time, the amount of gas remaining in the gas cylinder (gas pressure) is measured from the load applied to the load cell. The latter device using a Bourdon tube type pressure gauge measures the pressure inside the gas cylinder with a Bourdon tube type pressure gauge and displays this measured value by rotating the pointer on a dial with a scale. The configuration is such that the remaining gas amount is grasped as pressure.

Further, examples of the gas cylinder which is consumed at a constant flow rate include an oxygen cylinder used in a portable oxygen inhaler for home medical care. In recent years, an increasing number of patients need oxygen inhalation due to respiratory diseases, and the number of home patients is also increasing. A home patient is equipped with various equipment such as an oxygen cylinder, a pressure regulator, and a flow controller in his / her home, and inhales a required constant flow of oxygen according to a doctor's instruction. The oxygen cylinder used in the portable oxygen inhaler for home medical care is often equipped with the device using the above-mentioned Bourdon tube pressure gauge.

[0004]

However, in the device using the conventional Bourdon tube pressure gauge described above, the remaining usable time of the cylinder must be estimated from the pressure value of the gas in the cylinder indicated by the pointer. In addition, since it takes time to guess the time, it is not easy to use and there is a problem that the remaining usage time cannot be accurately grasped. Also, if the usage conditions of the cylinder change due to changes in the inhalation flow rate or the capacity of the cylinder according to the doctor's instructions, the relationship between the pressure value of the gas in the cylinder and the remaining usage time will change. Therefore, each time the condition is changed, the patient who is the user of the cylinder has to read the pressure value from the remaining usage time according to the condition at that time. Therefore, there are problems that it takes time and labor, it takes time to get used to the relationship between the new pressure value after the condition change and the remaining usage time, and there is a risk of misunderstanding of the remaining usage time. Then, if a mistake is made in grasping the oxygen, there is a situation in which the oxygen inhalation is interrupted due to the fact that it is present even though there is actually no remaining usage time. In addition,
The above-mentioned problems occur not only in oxygen cylinders used in portable oxygen inhalers for home medical care but also in other gas cylinders.

Furthermore, even when the apparatus using the above-mentioned conventional load cell is mounted on the gas cylinder, there is no change in that the pressure value (or load value) must be read to the remaining usage time. The same problem occurs as in the case of the device using the pressure gauge. Also,
The device using the load cell has a problem that it can be applied only to a cylinder that is fixedly used and cannot be applied to the portable oxygen cylinder for home medical care described above.

It is an object of the present invention to provide a gas fuel gauge capable of accurately and quickly grasping the remaining usage time of a gas cylinder and easily handled even by an unskilled person. Another object of the present invention is to provide, in addition to the above object, a gas fuel gauge capable of easily and promptly responding to changes in gas consumption flow rate and cylinder capacity.

[0007]

The present invention is intended to achieve the above object by calculating the remaining usage time of the cylinder from the pressure in the gas cylinder. Specifically, the gas fuel gauge of the present invention is a pressure measuring means for measuring the pressure of the gas in the gas cylinder, and a flow rate set value storage means for storing the set value of the consumption flow rate of the gas supplied from the gas cylinder to the outside. A capacity set value storage means for storing the set value of the capacity of the gas cylinder, and a set value of the gas consumption flow rate stored in the flow rate set value storage means and a set value of the cylinder capacity stored in the volume set value storage means. The remaining usage time calculating means for calculating the remaining usage time of the gas cylinder from the residual pressure of the gas in the gas cylinder measured by the pressure measuring means and the remaining usage time for displaying the remaining usage time calculated by the remaining usage time calculating means. And a time display means.

Here, as the pressure measuring means, a pressure sensor using a strain gauge type or an electrostatic capacitance type detecting method, or a pressure sensor having a structure of a diaphragm type or a bellows type or the like, the pressure of the gas in the gas cylinder is used. Any can be applied as long as it can measure. Further, the display by the remaining usage time display means may be a digital display in which hours, minutes, and seconds are represented by numbers, or an analog display using a pointer, a scale, or the like, and a length in which the remaining usage time is divided stepwise. It may be a bar graph display represented by, a display that lights or blinks only the position or section that indicates the remaining usage time, or a voice display (sound display alone or a combination of each of the above displays and sound display), but easy to grasp In view of the above, it is preferable to use digital display.

Furthermore, the set value of the gas consumption flow rate stored in the flow rate set value storage means and the set value of the cylinder capacity stored in the capacity set value storage means may be fixed values that are not changed. However, there are a flow rate setting means for inputting and setting the set value of the gas consumption flow rate to be stored in the flow rate setting value storage means, and a capacity setting means for inputting and setting the set value of the cylinder capacity to be stored in the capacity set value storage means. It is preferable to provide such a configuration that these setting values can be changed. The input setting method of these set values may be a method of selecting from a plurality of predetermined candidate values, or a method of the user inputting an arbitrary numerical value.

Further, in the vicinity of the remaining usage time display means, the flow rate set value display means for displaying the set value of the consumed flow rate of the gas stored in the flow rate set value storage means, or the inside of the gas cylinder measured by the pressure measuring means. It is preferable to provide a cylinder internal pressure display means for displaying the gas pressure. The display by the flow rate set value display means or the cylinder internal pressure display means may be any display method such as digital display, analog display, bar graph display, etc., as in the case of the remaining usage time display means. When the remaining usage time display means is digitally displayed, it is preferable to use another display method such as a bar graph display to distinguish it from the digital display. By doing so, it becomes easier to grasp the remaining usage time. , There is no risk of mistaking each display.

Furthermore, the passage of time, the amount of change in the measured value of the gas pressure by the pressure measuring means, the set value of the gas consumption flow rate stored in the flow rate set value storage means, and the cylinder stored in the capacity set value storage means. From the viewpoint of battery consumption reduction and energy saving, it is possible to determine the gas consumption by referring to the set value of the capacity, and to have an automatic off means to automatically turn off the battery power or put it into sleep mode. preferable.

Further, as a preferred application example of the gas fuel gauge of the present invention, it is possible to attach it to an oxygen cylinder used in a portable oxygen inhaler for home medical care.

[0013]

In the present invention as described above, the set value of the gas consumption flow rate is stored in advance in the flow rate set value storage means, and the set value of the cylinder capacity is stored in the capacity set value storage means. The pressure of the gas in the gas cylinder is measured, and the remaining usage time of the gas cylinder is calculated from the measurement value of the residual pressure of the gas by the remaining usage time calculation means by using the respective set values stored in the flow rate set value storage means and the capacity set value storage means. Is calculated and the calculation result is displayed by the remaining usage time display means.

For this reason, the user of the gas cylinder can easily grasp the remaining usage time of the cylinder simply by looking at or listening to the display by the remaining usage time display means, and thus the gas can be used as in the conventional gas cylinder. Since it is not necessary to read the pressure value of No. 1 to the remaining usage time, the remaining usage time of the cylinder can be grasped accurately and quickly. In addition, since there is no need to read from the pressure value to the remaining usage time, even people who are not familiar with the device can easily handle it, and there is no risk of misreading due to unfamiliarity or misunderstanding. The purpose is achieved.

Further, when the flow rate setting means and the capacity setting means are provided so that the set value of the gas consumption flow rate and the set value of the cylinder capacity can be changed, the gas consumption flow rate may change (for example, the When the gas level meter of the invention is attached to an oxygen cylinder used in a portable oxygen inhaler for home medical care, when the inhalation flow rate is changed according to a doctor's instruction), or the capacity of the cylinder is changed It becomes possible to easily and quickly respond to changes in conditions. In other words, when the usage conditions of the cylinder change, the relationship between the pressure value of the gas in the cylinder and the remaining usage time changes, but it is only necessary to change each setting value according to the condition change by the flow rate setting means and the capacity setting means. Then, the remaining usage time calculating means can accurately calculate the remaining usage time. For this reason, the conventional problems such as it takes time for the cylinder user to get used to the relationship between the new pressure value after the condition change and the remaining usage time, or the risk of misunderstanding of the remaining usage time is solved. .

Further, when the flow rate set value display means for displaying the set value of the consumed flow rate of the gas stored in the flow rate set value storage means is provided near the remaining used time display means, the remaining used time calculation means Since the set value of the consumption flow rate used in the calculation process by the can be easily grasped, it is easy to find the setting mistake or the change mistake of the set value of the consumption flow rate that has a relatively large chance to change. The calculation error of the remaining usage time due to the mistake is surely prevented.

Further, in the vicinity of the remaining usage time display means,
When the cylinder internal pressure display means for displaying the pressure of the gas in the gas cylinder measured by the pressure measuring means is provided, it is possible to grasp the remaining usage time by reading from the pressure value which has been conventionally performed. Even a person who is accustomed to the conventional device can smoothly shift to the direct grasp of the remaining usage time.

Further, an automatic off means is provided, and when there is no change in the measured value of the gas pressure by the pressure measuring means even after a lapse of a certain time, it is judged that the gas is not consumed (is not in use) and automatically. If the battery-powered device is turned off or put into a sleep state, battery consumption can be reduced and energy can be saved. At this time, the threshold value of the amount of change in the measured value that serves as a reference for determining whether or not the gas is being used is the set value of the consumed flow rate of the gas stored in the flow rate set value storage means, and the capacity set value storage means. It is set according to the magnitude of the set value of the cylinder capacity stored in.

Further, when the gas fuel gauge of the present invention is attached to an oxygen cylinder used in a portable oxygen inhaler for home medical care, the oxygen cylinder consumes at a constant flow rate and the remaining usage time is accurate. Since such grasping is essential, the action and effect of the present invention as described above can be more remarkably exhibited.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a portable oxygen inhalation system 10 for home medical care according to this embodiment. The oxygen inhalation system 10 includes an oxygen cylinder 11 having oxygen gas therein,
A cylinder valve 12 provided on top of the oxygen cylinder 11,
A gas level meter 20 provided near the cylinder valve 12 for measuring and displaying the amount of oxygen gas remaining in the oxygen cylinder 11, and a flow rate of oxygen gas supplied from the oxygen cylinder 11 to an external point of use are adjusted. A flow rate adjusting valve 13 and a flow rate setting dial 14 for operating the opening degree of the flow rate adjusting valve 13 are provided.

FIG. 2 shows a front view of the gas fuel gauge 20, and FIG. 3 shows the gas fuel gauge 20 taken along the line AA in FIG.
A cross-sectional view of is shown. Further, FIG. 4 shows a signal flow between the respective parts of the gas fuel gauge 20 as a block diagram. 2 and 3, the gas fuel gauge 20 includes a case 21 that covers the outer periphery, a front panel 22 that is partially or entirely transparent, and a liquid crystal display (LCD) 30 that is fitted inside the front panel 22. A circuit section 40 formed on the surface of a substrate provided in a space surrounded by the case 21 and the front panel 22 and a battery 25 connected to the circuit section 40 are provided.

On the back side of the gas fuel gauge 20, there is provided a connection joint 27 having a gas introduction hole 26 for guiding the pressure of the oxygen gas in the oxygen cylinder 11, and this connection joint 27 is provided.
A pressure sensor 28, which is a pressure measuring means for measuring the pressure of the oxygen gas guided to the gas introduction hole 26, is provided inside the. The pressure sensor 28 is connected to the circuit unit 40 by a conductor (not shown) or the like. The pressure sensor 28 includes
For example, a strain gauge type pressure sensor having a diaphragm type structure can be used.

The liquid crystal display 30 is an oxygen cylinder 11
The remaining usage time display section 31 which is a remaining usage time display means for digitally displaying the remaining usage time of the gas, and the flow rate set value display means for displaying the set value of the gas consumption flow rate in a bar graph arranged in the horizontal direction in FIG. A certain flow rate set value display unit 32, and a cylinder internal pressure display unit 33 which is a cylinder internal pressure display unit for displaying the gas pressure in the oxygen cylinder 11 measured by the pressure sensor 28 in a bar graph vertically arranged in FIG. Is equipped with. In addition, the front panel 22 has each of the display units 31 to 31.
A SET button 60 and an ON button 61 for switching the mode or turning on the power of the gas fuel gauge 20 are provided on the lower side of the arrangement position of 33 in FIG. The details of the mode will be described later.

In FIG. 4, the circuit section 40 includes an amplifier 41 for amplifying the pressure value signal S1 sent from the pressure sensor 28 and a remaining usage time of the oxygen cylinder 11 based on the pressure value signal S2 received from the amplifier 41. A central processing unit (CPU) 42 that performs calculation processing, a power supply circuit 43 that receives a power supply / oscillation ON-OFF signal S3 output from the CPU 42 and applies a predetermined voltage to the pressure sensor 28 and the amplifier 41, and a power supply An oscillation circuit 44 that receives the oscillation ON-OFF signal S3 and sends an electric signal of a predetermined oscillation frequency to the CPU 42. Power supply circuit 43 and CPU 42
Is connected to the battery 25.

Further, the circuit section 40 has a flow rate set value storage means 50 for storing the set value of the consumption flow rate of the gas supplied from the oxygen cylinder 11 to the outside, and the flow rate set value storage means 50.
Flow rate candidate value storage means 51 for pre-storing a plurality of candidate values for the set value of the consumed flow rate to be stored in and capacity set value storage means 52 for storing the set value of the capacity of the oxygen cylinder 11.
And a cylinder internal pressure storage means 53 for temporarily storing the pressure value measured by the pressure sensor 28. Among these, the flow rate candidate value storage means 51 and the cylinder internal pressure storage means 5
3 is provided inside the CPU 42.

The flow rate set value storage means 50 is composed of a readable / writable memory (EEPROM, RAM) or the like, and is selected by the user from a plurality of candidate values stored in the flow rate candidate value storage means 51. One candidate value is stored as the set value. The flow rate candidate value storage means 51 is composed of a read-only memory (ROM) or the like, and has a plurality of flow rate candidate values selectable as set values, for example, 0.5, 1, 1.5, 2, 2.5 NL / min. Five flow rate candidate values of (liter per minute in standard state) are stored. The capacity setting value storage means 52 reads and
It is composed of a writable memory (EEPROM, RAM) and the like, and the capacity of the oxygen cylinder 11 is stored up to 9.9 liters in 0.1 liter increments within a range of one digit above the decimal point and one digit below the decimal point. It has become so. The cylinder internal pressure storage means 53 is composed of a readable / writable memory (RAM) and the like, and the pressure sensor 2
The pressure value sequentially measured by 8 is stored while being updated at regular time intervals.

The CPU 42 is an A / D converter 45 for converting the pressure value signal S2, which is an analog signal, into a digital signal.
And a remaining usage time calculation processing unit 46, which is a remaining usage time calculation means for calculating the remaining usage time of the oxygen cylinder 11, and an automatic power-off or sleep mode when it is determined that no gas is consumed. An automatic off processing section 47 which is an off means, a flow rate setting mode processing section 48 for inputting and setting a set value of the consumed flow rate, and a capacity setting mode processing section 49 for inputting and setting a set value of the capacity of the oxygen cylinder 11. The above-mentioned flow rate candidate value storage means 51 and cylinder internal pressure storage means 53
It has and. The flow rate set value storage means 50 and the capacity set value storage means 52 may be provided inside the CPU 42.

The remaining usage time calculation processing section 46 stores in the cylinder internal pressure P received from the A / D conversion section 45, the set value of the consumed flow rate Q stored in the flow rate set value storage means 50, and the capacity set value storage means 52. Based on the stored information on the set value of the capacity V of the oxygen cylinder 11, the oxygen cylinder 1 is calculated by the following equation.
The remaining usage time T of 1 is calculated. T = P × V / Q That is, in the above equation, the consumption flow rate Q and the cylinder capacity V
Is a constant value during use, the remaining use time T is obtained as a linear function of the cylinder internal pressure P.

The automatic off processing section 47 includes an A / D conversion section 45.
The present value of the cylinder internal pressure received from the tank is compared with the past value stored in the cylinder internal pressure storage means 53 for a certain period of time, and when the difference is within a certain range, no gas is consumed (not used). Power supply / oscillation ON-OFF signal S
3 is output as an OFF signal, and the power is automatically turned off or the sleep state is set. Further, the threshold value that defines a certain range for determining whether or not it is in use is the currently set consumption flow rate Q and the cylinder capacity V.
Are set according to the size of each set value.

The flow rate setting mode processing unit 48 sends a SET button 60 to the command signal for shifting to the flow rate setting mode by the user.
When receiving from, the one candidate value selected by the user from the plurality of candidate values stored in the flow rate candidate value storage means 51 is displayed while performing various displays necessary for input setting on the liquid crystal display 30. The setting value is stored in the flow rate setting value storage means 50. The user selects the set value by operating the SET button 60 and the ON button 61. Then, the flow rate setting mode processing unit 4
8, the SET button 60, and the ON button 61
A flow rate setting means is configured.

The capacity setting mode processing section 49 sends a set command signal to the capacity setting mode signal from the user.
When it is received from the ON button 61 and the ON button 61, various values required for input setting are displayed on the liquid crystal display 30, and a value arbitrarily input by the user is stored in the capacity setting value storage means 52 as a setting value. Has become. The SET button 60 and ON are used for the user to input the set value.
This is performed by operating the button 61. The capacity setting mode processing unit 49, the SET button 60, and the ON button 61 constitute a capacity setting means.

In this embodiment, the gas fuel gauge 20 is used in each mode as follows. [Remaining usage time display mode] First, when the ON button 61 is pressed to turn on the gas fuel gauge 20, the remaining usage time display mode executed in a normal usage state is activated. In the remaining usage time display mode, the remaining usage time calculation processing unit 46 calculates the remaining usage time based on the measurement value of the pressure sensor 28, and the calculation result is displayed on the remaining usage time display unit 31 of the liquid crystal display 30.

Further, in this remaining usage time display mode,
The flow rate set value display section 32 displays the set value of the gas consumption flow rate used in the calculation processing by the remaining usage time calculation processing section 46 (the set value currently stored in the flow rate set value storage means 50). . The display of the flow rate setting value display section 32 is
This is performed by turning on the position corresponding to each value described on the lower side.

Further, in the remaining usage time display mode, the cylinder internal pressure (the current value of the measured value sent from the pressure sensor 28) used in the calculation processing by the remaining usage time calculation processing section 46 is displayed. It is displayed on the part 33. Only the position corresponding to the remaining amount of the cylinder between the full state (symbol F) and the empty state (symbol E) shown on the left side of the cylinder internal pressure display portion 33 is turned on or displayed from the corresponding position. This is done by turning on all sides. Then, in the remaining usage time display mode, the power-off / oscillation ON-OFF signal S3 is turned off by the automatic-off processing unit 47.
It will continue to run unless signaled.

[Capacity Setting Mode] Next, an example of cylinder capacity setting will be described. For example, SET button 60 and ON
When the buttons 61 are simultaneously pressed for 3 seconds or more, the capacity setting mode is activated. At this time, "CAP" is displayed on the remaining usage time display section 31 to inform that the capacity setting mode has been entered.

In this capacity setting mode, the currently set cylinder capacity is first digitally displayed in the remaining usage time display portion 31 with one digit after the decimal point and one digit after the decimal point, and the upper digit thereof is in a blinking state. . When the SET button 60 is pressed in this blinking state, the blinking upper digit number is incremented by one. When the desired value is reached, the ON button 61 is pressed to fix the value and the blinking stops. Then, the lower digit blinks at the same time when the upper digit is fixed, and similarly to the case of the upper digit, the SET button 60 is pressed to set the lower digit to a desired value, and the ON button 61 is pressed to fix the lower digit. . When the setting of these upper digit and lower digit is completed, it automatically returns to the remaining usage time display mode.

In addition, about 10 while the capacity setting mode is entered.
If no operation is performed for a second, the setting value is not changed and the remaining use time display mode is automatically returned. Then, when returning from the capacity setting mode to the remaining usage time display mode, the newly set setting value is displayed for about 2 seconds.

[Flow Rate Setting Mode] Further, an example of flow rate setting will be described. For example, if only the SET button 60 is pressed for 5 seconds or longer, the flow rate setting mode is activated. On this occasion,
"FLO" is displayed on the remaining usage time display section 31,
It is informed that the flow rate setting mode has been entered.

In this flow rate setting mode, the currently set consumption flow rate is first lit and displayed on the bar graph of the flow rate setting value display section 32. In this state, SET button 6
When 0 is pressed, the lighting position on the bar graph moves. Then, when the ON position of the desired value is reached at the lighting position, the ON button 61 is pressed to confirm the value as a set value, and then the display automatically returns to the remaining usage time display mode. Further, when about 10 seconds or more elapses without pressing the ON button 61 while the flow rate setting mode is being entered, the mode automatically returns to the remaining usage time display mode. At this time, the set value remains the previous set value.

According to this embodiment, the following effects can be obtained. That is, since the remaining usage time is displayed on the remaining usage time display unit 31, the user can easily grasp the remaining usage time of the oxygen cylinder 11 only by looking at this display. It is no longer necessary to read the pressure value from the pressure value to the remaining usage time, and the remaining usage time can be grasped more accurately and quickly than before.

Since the display of the remaining usage time display section 31 is a digital display, it can be grasped more easily. Further, since there is no need to replace the pressure value with the remaining usage time, even a person who is not familiar with the device can easily handle it, and the risk of misreading due to inexperience or misunderstanding can be eliminated.

Further, since the set value of the gas consumption flow rate and the set value of the cylinder capacity can be changed in the flow rate setting mode and the volume setting mode, the inhalation flow rate (gas consumption flow rate) is changed or the cylinder is instructed by a doctor. It is possible to easily and quickly respond to changes in the operating conditions of the cylinder due to changes in the capacity of the cylinder.

In the remaining use time display mode which is the normal state, the set value currently stored in the flow set value storage means 50 is displayed on the flow set value display section 32, so that the remaining used time calculation processing section is provided. Since the set value used in the calculation process by 46 can be easily grasped, it becomes easy to find the setting error or the setting error of the set value of the consumption flow rate, which has a relatively large chance of being changed. It is possible to reliably prevent the calculation error of the remaining usage time due to the error.

In the remaining usage time display mode, which is the normal state, the current value of the measured value of the internal cylinder pressure sent from the pressure sensor 28 is displayed on the internal cylinder pressure display section 33, which is conventionally performed. The remaining usage time can be grasped by reading from the pressure value, and even a person who is accustomed to the conventional device can smoothly shift to the grasp by directly reading the remaining usage time.

Further, since the automatic off processing unit 47 is provided, when the gas fuel gauge 20 is not in use, the power of the gas fuel gauge 20 can be automatically turned off or in the sleep state. It is possible to reduce battery consumption and save energy.

The present invention is not limited to the above-mentioned embodiments, and modifications and the like within the range in which the object of the present invention can be achieved are included in the present invention. That is, in the above-described embodiment, the flow rate setting means and the volume setting means constituted by the SET button 60, the ON button 61, the flow rate setting mode processing section 48, and the volume setting mode processing section 49 are provided. Are not necessary for the invention. However, it is preferable to provide these means, and by doing so, the set values of the consumption flow rate and the cylinder capacity can be easily changed, and the function of the gas fuel gauge 20 can be improved.

Further, in the above embodiment, the flow rate set value display section 32 and the cylinder internal pressure display section 33 are provided.
These display units are not always necessary for the present invention, and in short, the remaining usage time display unit 31 may be provided. However, it is preferable to provide the flow rate set value display unit 32 because it is possible to reliably prevent the calculation error of the remaining usage time due to the setting error or the change error of the flow rate setting value, and the cylinder internal pressure display unit 33 is provided. It is preferable that the person who is accustomed to the conventional device can smoothly shift to the direct grasp of the remaining usage time of the present invention.

Further, in the above-mentioned embodiment, the remaining use time display means, the flow rate set value display means and the cylinder internal pressure display means are constituted by the respective display portions 31 to 33 of the liquid crystal display 30, but these means are CRTs. It may be configured by another device such as a display.

Further, the gas fuel gauge 20 of the above-mentioned embodiment was applied to the portable oxygen inhalation system 10 for home medical care, but the gas fuel gauge of the present invention is limited to such an application example. However, the present invention may be applied to, for example, measuring the remaining amount of welding gas in an automatic welding machine, measuring the remaining amount of gas used in semiconductor manufacturing, and in other words, a gas cylinder that consumes at a constant flow rate. It can be applied as long as the remaining amount of gas inside is measured.

[0050]

As described above, according to the present invention, the pressure measuring means measures each set value stored in the flow rate set value storage means and the volume set value storage means by the remaining usage time calculation means. The remaining usage time of the gas cylinder is calculated from the remaining pressure of the gas, and the calculation result is displayed by the remaining usage time display means, so that the user of the gas cylinder can use the remaining usage of the cylinder just by looking at or listening to this display. Since it is possible to easily grasp the time, there is no need to replace the conventional gas pressure value with the remaining usage time, and the remaining usage time of the cylinder can be grasped accurately and quickly, and you are accustomed to the equipment. Even an inexperienced person can easily handle it, and there is an effect that it is possible to eliminate the risk of misreading due to inexperience or misunderstanding.

Further, when the flow rate setting means and the capacity setting means are provided so that the set value of the gas consumption flow rate and the set value of the cylinder capacity can be changed, the operating conditions of the cylinder can be changed easily and quickly. There is an effect that it can respond and the function of the device can be improved.

Further, when the flow rate set value display means is provided, the set value of the consumed flow rate used for the calculation processing by the remaining usage time calculation means can be easily grasped, so that the consumption rate is changed relatively frequently. There is an effect that it is easy to find a setting mistake or a change mistake of the set value of the flow rate, and it is possible to reliably prevent a calculation mistake of the remaining usage time due to the setting mistake or the change mistake.

Further, when the cylinder internal pressure display means is provided, the remaining usage time can be grasped by reading the pressure value which has been conventionally used, so that even a person who is accustomed to the conventional apparatus can use the remaining pressure. This has the effect of smoothly shifting to the direct grasp of time.

When an automatic off means is provided,
It is possible to automatically determine that the cylinder is not in use and turn off the battery-powered gas fuel gauge or put it into a sleep state. This has the effect of reducing battery consumption and saving energy. .

Further, when the gas fuel gauge of the present invention is attached to an oxygen cylinder used in a portable oxygen inhaler for home medical care, the oxygen cylinder consumes at a constant flow rate and the remaining usage time is accurate. Since it is indispensable to grasp such information, there is an effect that the effect of the present invention can be more remarkably exhibited.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a portable oxygen inhalation system for home medical use equipped with a gas fuel gauge according to an embodiment of the present invention.

FIG. 2 is a front view of the gas fuel gauge of the embodiment.

FIG. 3 is a cross-sectional view of the gas fuel gauge of the above embodiment taken along the line AA in FIG.

FIG. 4 is a block diagram showing a signal flow between respective parts of the gas fuel gauge of the embodiment.

[Explanation of symbols]

10 Portable Oxygen Inhalation System for Home Health Care 11 Oxygen Cylinder 20 Gas Fuel Gauge 28 Pressure Sensor as Pressure Measuring Means 31 Remaining Usage Time Display Unit of Liquid Crystal Display as Remaining Usage Time Display Means 32 Flow Rate Setting Value Display Means Flow rate setting value display section of liquid crystal display 33 Cylinder internal pressure display section of liquid crystal display which is cylinder internal pressure display means 46 Remaining usage time calculation processing section 47 which is remaining usage time calculation means 47 Automatic off processing section which is automatic off means 48 Flow rate setting means The flow rate setting mode processing unit 49 constituting the capacity setting unit 50 the capacity setting mode processing unit constituting the capacity setting unit 50 the flow rate setting value storage unit 52 the capacity setting value storage unit 53 the cylinder internal pressure storage unit 60 the SE configuring the flow rate setting unit and the capacity setting unit
T button 61 ON which constitutes flow rate setting means and capacity setting means
button

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jinichi Todoroki 1-30-4 Higashimagome, Ota-ku, Tokyo President of Nokei Keiki Co., Ltd. (72) Inventor Takuma Takeuchi 1-30-Higashimagome, Ota-ku, Tokyo 4 In stock company president Nokiki Seisakusho (72) Inventor Masakazu Okubo 1318, Ojiwara, Ageo City, Saitama Prefecture Daito Valve Seisakusho Co., Ltd. (56) Reference JP-A-3-261274 (JP, A) JP 4 -262199 (JP, A)

Claims (6)

(57) [Claims] 1. A pressure measuring means for measuring a pressure of gas in a gas cylinder, a flow rate set value storing means for storing a set value of a consumption flow rate of gas supplied from the gas cylinder to the outside, and a capacity setting of the gas cylinder. The pressure measurement using a capacity set value storage means for storing a value, a gas consumption flow rate set value stored in the flow rate set value storage means, and a cylinder capacity set value stored in the capacity set value storage means. Remaining usage time calculation means for calculating the remaining usage time of the gas cylinder from the residual pressure of the gas in the gas cylinder measured by the means, and remaining usage time display means for displaying the remaining usage time calculated by the remaining usage time calculation means. Gas fuel gauge characterized by having and. 2. The gas fuel gauge according to claim 1, wherein the flow rate setting means for inputting and setting a set value of the consumption flow rate of the gas stored in the flow rate setting value storage means and the capacity set value storage means. A gas fuel gauge, comprising: a capacity setting means for inputting and setting a set value of a cylinder capacity to be stored. 3. The gas fuel gauge according to claim 1 or 2, wherein a set value of the consumption flow rate of gas stored in the flow rate set value storage means is provided near the remaining usage time display means. A gas fuel gauge characterized in that a flow rate set value display means for displaying is provided. 4. The gas fuel gauge according to any one of claims 1 to 3, wherein the gas pressure in the gas cylinder measured by the pressure measuring means is provided in the vicinity of the remaining usage time display means. A gas fuel gauge, characterized in that it is provided with a cylinder internal pressure display means for displaying. 5. The gas fuel gauge according to any one of claims 1 to 4, wherein the passage of time, the amount of change in the measured value of the gas pressure by the pressure measuring means, and the flow rate set value storage means are stored. It is determined that there is no gas consumption by referring to the set value of the consumed gas flow rate and the set value of the cylinder capacity stored in the capacity set value storage means, and the battery-powered power is automatically turned off or A gas fuel gauge, which is provided with an automatic off means for putting it into a sleep state. 6. The gas fuel gauge according to any one of claims 1 to 5, wherein the gas cylinder is an oxygen cylinder used for a portable oxygen inhaler for home medical care. Quantity meter.