JP4779137B2 - Gas supply system to container and gas supply method to container - Google Patents

Description

  The present invention relates to a gas supply system and a gas supply method for supplying gas to a container for storing powder such as powder.

  For example, reduced iron powder powder must be stored without contact with the atmosphere. As a device for storing such powder that should be prevented from coming into contact with the atmosphere, it is equipped with a gas supply passage that supplies pressurized inert gas such as nitrogen to a sealed container that stores the powder. Is known (see Patent Document 1). This container can maintain a state in which the inside of the container is purged with a gas even when powder is charged into or discharged from the container. In other words, the powder can be charged and discharged without bringing the powder into contact with the atmosphere.

  Moreover, the pressure gauge which measures the internal pressure in a container is provided in this container. When supplying gas into the container, the operator visually monitors the measured value of the pressure gauge and continues to supply gas until the internal pressure reaches a predetermined positive pressure (positive pressure relative to atmospheric pressure). When the positive pressure is confirmed, the on-off valve provided in the gas supply path is closed to stop the gas supply. By making the inside of the container a positive pressure in this way, it is possible to prevent the atmosphere from entering the container.

Japanese Patent No. 3409974

  However, in the conventional gas supply method, the worker starts other work during the gas supply, forgets that the gas is being supplied, or misreads the pressure gauge or operates the on-off valve. In some cases, carelessness of such an operator may cause excessive gas supply into the container. As a result, the inside of the container was pressurized to a high pressure, and the container was damaged, and the powder was exposed to the atmosphere, resulting in a defective product. In particular, when the amount of powder stored in each container is different, the elapsed time from the start of gas supply until the container reaches a predetermined positive pressure is different for each container. It was necessary to carefully monitor the operation, which was cumbersome and easy to cause carelessness of workers. In addition, a filter is provided between the inside of the container and the outlet of the gas supply path to prevent the powder from entering the gas supply path. The condition may vary from container to container. In other words, the flow rate of the gas supplied to the container varies, and in this case as well, the elapsed time until reaching a predetermined positive pressure may vary greatly, which is easy to cause carelessness of the operator. .

  The present invention has been made in view of the above points. A gas supply system capable of automatically performing a gas supply operation into a container and accurately adjusting an internal pressure in the container, and a gas An object is to provide a supply method.

  In order to solve the above problems, according to the present invention, there is provided a system for supplying gas to a container for storing powder, wherein the gas supply path for supplying gas into the container and the gas supply path A supply pressure adjusting mechanism for switching a supply pressure of the gas supplied into the container, and a control unit for controlling the supply pressure adjusting mechanism, wherein the control unit supplies the gas into the container at a first supply pressure. After the supply, the gas supply pressure is set to a second supply pressure lower than the first supply pressure, and the gas is supplied into the container until the inside of the container reaches a predetermined internal pressure. A system for supplying gas to a container is provided that is characterized in that it does.

  According to such a gas supply system, the gas can be automatically supplied into the container under the control of the control unit. In addition, by supplying the gas at the first supply pressure and then supplying the gas at the second supply pressure, excessive pressurization in the container can be prevented, and the gas can be supplied safely.

  The control unit detects a spatial volume obtained by subtracting the volume of the powder stored in the container from the total volume in the container based on an integrated supply amount of the gas supplied into the container and an internal pressure in the container. A function and a function of calculating an additional integrated supply amount necessary for pressurizing the internal pressure of the space volume to a predetermined value may be provided.

  The supply pressure adjusting mechanism includes a main introduction path that supplies the gas under pressure from a gas supply source, and a first flow that supplies the gas from the main introduction path to the gas supply path at the first supply pressure. It is good also as a structure provided with a 2nd flow path which supplies the said gas to said gas supply path from said main introduction path to said gas supply path by said 2nd supply pressure. The first channel is provided with a first on-off valve for communicating and blocking the first channel, and the second channel is supplied with gas passing through the second channel. A pressure adjustment valve that reduces the pressure to the second supply pressure and a second opening / closing valve that allows the second flow path to communicate and block may be provided.

  An integrated flow meter for measuring the integrated flow rate of the gas supplied to the gas supply path may be provided. Moreover, you may provide the pressure gauge which measures the internal pressure in the said container.

  According to the present invention, there is also provided a method for supplying gas to a container for storing powder, wherein the gas is supplied into the container at a first supply pressure, and then the supply pressure of the gas is set to the There is provided a gas supply method to a container, wherein the gas is supplied into the container at a second supply pressure lower than the first supply pressure, and the container is set to a predetermined internal pressure. The

  In this method, before supplying the gas at the first supply pressure, the gas is supplied into the container, and then the internal pressure in the container is measured, and the integrated value supplied into the container is measured. A space volume obtained by subtracting the volume of the powder stored in the container from the total volume in the container is calculated from the supply amount and the measured internal pressure, and the inside of the container is calculated based on the space volume. An additional integrated supply amount required to pressurize to the internal pressure is obtained, and a first integrated supply amount of the additional integrated supply amount is supplied at the first supply pressure, and the first integrated supply amount is calculated from the additional integrated supply amount. A second integrated supply amount obtained by subtracting the integrated supply amount may be supplied at the second supply pressure.

  Before measuring the internal pressure in the container, gas may be discharged from a gas supply path that supplies gas into the container, and the pressure in the gas supply path may be reduced. Further, when the flow rate of the gas supplied into the container is not within a predetermined range, the supply of the gas into the container may be stopped and an alarm may be generated. If the supply by the second supply pressure does not end within a predetermined elapsed time, the supply of gas into the container may be stopped and an alarm may be generated.

  After the supply by the second supply pressure is completed, when the pressure in the gas supply path for supplying the gas into the container decreases, the gas may be supplied to the gas supply path.

  That is, the present invention has been made in consideration of the automation of the pressurization work performed on a closed container (container) containing iron powder or the like. By using the integrated flow meter instead of the elapsed time of pressurization, pressurization can be performed accurately. The inside of the container can be properly pressurized even when the filter to which the gas supply hose (gas supply path) is connected is different or when the filter is clogged.

  According to the present invention, the gas can be automatically supplied into the container under the control of the control unit. An excessive supply of gas into the container can be prevented. By supplying the gas at the first supply pressure and then supplying it at the second supply pressure, it is possible to reliably prevent overpressurization in the container. By determining the gas supply stop based on the integrated supply amount, the inside of the container can be pressurized more accurately than when the gas supply stop is determined based on the elapsed time.

Hereinafter, preferred embodiments of the present invention will be described. As shown in FIG. 1, a gas supply system 1 according to this embodiment includes a hose 3 having a gas supply path 3a for supplying, for example, nitrogen (N ₂ ) gas as a gas (inert gas) into a container 2 and gas. A supply pressure adjusting mechanism 5 for switching the supply pressure of the gas supplied into the container 2 by the supply path 3a and a control unit 6 for controlling the supply pressure adjusting mechanism 5 are provided.

  In the internal space 2 a of the container 2, reduced iron powder as powder to be stored is stored. In addition, the container 2 is provided with an inlet / outlet 7 for feeding iron powder into the container 2 and discharging iron powder from the container 2. The inlet / outlet 7 is provided with an opening / closing valve 7 a for opening and closing the inlet / outlet 7. For example, a butterfly valve or the like is used as the on-off valve 7a.

  The container 2 is provided with a pressure gauge 10 as a container pressure gauge for measuring the internal pressure in the container 2. The pressure gauge 10 is provided at an end portion of a pipe line 11 extending outward from the casing of the container 2 and can be detached from the pipe line 11. The measured value of the pressure gauge 10 is transmitted to the control unit 6. In the pipe line 11, a safety valve 12 is provided between the pressure gauge 10 and the container 2. The safety valve 12 is opened, for example, when the inside of the container 2 is excessively pressurized, and has a function of lowering the pressure in the pipe line 11 so that the pressure gauge 10 does not break down due to excessive pressure. To be protected.

  Further, as shown in FIG. 2, the container 2 includes a connection cylinder 13 having a supply port 13 a for supplying gas to the container 2, and a connection tool 15 for connecting the connection cylinder 13 and the hose 3. Is provided. The connection tool 15 is provided with an on-off valve 22 for communicating and blocking the flow path in the connection tool 15. For example, a ball valve or the like is used as the on-off valve 22. By closing the on-off valve 22 and the on-off valve 7a of the inlet / outlet 7, the internal space 2a of the container 2 can be sealed. That is, the iron powder in the internal space 2a is shielded from the outside air (atmosphere), and the oxidation of the iron powder can be prevented.

  The connecting cylinder 13 has a substantially cylindrical shape and is provided so as to protrude outward from the housing of the container 2. The inside of the connection cylinder 13 serves as a supply port 13a and communicates with the storage space 2a. An internal thread portion 13 b is provided on the inner peripheral surface of the connection cylinder 13.

  The connection tool 15 includes a nipple 31 that connects the connection cylinder 13 and the opening / closing valve 22, and a coupler 32 that connects the opening / closing valve 22 and the end of the hose 3. The nipple 31 includes a cylinder body 31 a that is attached to the connection cylinder body 13. On the outer peripheral surface of the cylindrical body 31a, a male screw portion 31b that is screwed into the female screw portion 13b is provided. That is, the connecting screw 15 and the connecting cylinder 13 are coupled by screwing the female screw part 13a and the male screw part 31b and inserting the cylinder 31a into the connecting cylinder 13a.

  A filter 35 for preventing the iron powder in the container 2 from leaking to the outside through the supply port 13a is provided inside the connection cylinder 13. The filter 35 has a substantially disk shape, covers the tip end opening of the cylinder 31a, and is provided so as to partition the tip end opening of the cylinder 31a and the end of the supply port 13a. A spring 36 for pressing the filter 35 against the connecting cylinder 13 by an elastic force is provided inside the cylinder 31a. The spring 36 has a spiral shape and is provided along the inner peripheral surface of the cylindrical body 31a. Further, it is held in a compressed state between a step portion provided on the inner peripheral surface of the cylindrical body 31 a and the peripheral portion of the filter 35. In such a configuration, the gas supplied from the hose 3 passes through the flow path in the connector 15, passes through the filter 35, and then flows into the internal space 2a through the supply port 13a.

  In FIG. 1, the hose 3 has an elongated, substantially circular tubular shape having flexibility, and its internal space is a gas supply path 3a. The outlet end portion of the hose 3 is removable with respect to the connection tool 15 and is fixed to the connection tool 15 by being inserted into the coupler 32 of the connection tool 15.

  The gas supply path 3a is provided with a gas supply path pressure gauge 45 for measuring the pressure in the gas supply path 3a (gas supply pressure), and a discharge path 46 for discharging gas from the gas supply path 3a. The discharge passage 46 is provided with an on-off valve 47 that allows the discharge passage 46 to communicate with and shut off. The measurement value of the gas supply path pressure gauge 45 is transmitted to the control unit 6. The opening / closing operation of the opening / closing valve 47 is controlled by a control command of the control unit 6.

  The supply pressure adjusting mechanism 5 includes a main introduction path 50 that pressurizes and supplies gas from a gas supply source 48, a first flow path 51 that supplies gas from the main introduction path 50 to the gas supply path 3a, and a main flow path. A second flow path 52 for supplying gas from the introduction path 50 to the gas supply path 3a at a low pressure is provided. The flow path 51 and the flow path 52 are branched from the downstream end portion of the main introduction path 50 and are joined at the inlet end of the gas supply path 3a.

The main introduction path 50 includes an open / close valve 61 for communicating and blocking the main introduction path 50, a pressure adjusting valve 62 for adjusting the supply pressure of gas passing through the main introduction path 50 to a predetermined supply pressure _Ps1 , and the main introduction path 50. A thermometer 63 for measuring the temperature of the gas passing through the gas (that is, the temperature of the gas supplied to the gas supply passage 3a), and the integrated flow rate of the gas passing through the main introduction passage 50 (ie, supplied to the gas supply passage 3a). An integrated flow meter 64 for measuring the integrated gas flow rate is provided in this order from the gas supply source 48 side. The measured value of the thermometer 63 and the measured value of the integrated flow meter 64 are each transmitted to the control unit 6. The integrated flow meter 64 may be provided in the gas supply path 3a.

  The flow path 51 is provided with a first on-off valve 71 that allows the flow path 51 to communicate and shut off. The opening / closing operation of the opening / closing valve 71 is controlled by a control command of the control unit 6.

In the flow path 52, the pressure adjusting valve (pressure reducing valve) 72 that reduces the supply pressure of the gas passing through the flow path 52 from the supply pressure P _s1 to the second supply pressure P _s2 and the flow path 52 are communicated and blocked. A second on-off valve 73 is provided. The opening / closing operation of the opening / closing valve 73 is controlled by a control command of the control unit 6.

  In addition, the gas supply system 1 is provided with a signal lamp 81 that is turned on when an alarm is generated and a buzzer 82 that emits a warning sound when the alarm is generated. The operation of the signal lamp 81 and the operation of the buzzer 82 are controlled by control commands of the control unit 6, respectively. For example, the signal lamp 81 may light a green lamp during normal operation, and may light a red lamp when abnormal.

As described above, the control unit 6 monitors the measured values of the pressure gauge 10, the gas supply path pressure gauge 45, the thermometer 63, and the integrated flow meter 64, and the on-off valve 47, on-off valve 71, on-off valve 73. , A command for controlling the operation of the signal lamp 81 and the buzzer 82 is given. In addition, the control unit 6 can control the gas supply system 1 to automatically operate by executing control software, and can perform a gas supply process described in detail later. In this gas supply step, as will be described in detail later, after performing the _first gas supply step S4 and the first gas supply step S4 for supplying a predetermined integrated supply amount Q1 of gas into the container 2. It is included, such as late gas supply step S21 for supplying the additional cumulative supply quantity Q ₂ gas to the container 2, control for executing these processes is adapted to be sequentially performed. The late gas supply step S21 includes a first late gas supply step S21a for supplying gas into the container 2 at the first supply pressure _PS1 , and a second supply pressure P at which the gas supply pressure is lower than the supply pressure P1. _A second late gas supply step S21b supplied in S2 is included.

Further, the control unit 6 determines the space volume V _r [L] in the container 2 (total volume V _c [L in the container 2] from the measured value of the pressure gauge 10 and the measured value (integrated supply amount) of the integrated flow meter 64. ], The volume obtained by subtracting the volume V _p [L] of the iron powder stored in the container 2: V _r = V _m −V _p ). Furthermore, the control unit 6 uses the calculated space volume V _r to add an additional integrated supply amount Q ₂ [necessary to be added to pressurize the container 2 to a predetermined internal pressure (target value) P _c2 . L] can be calculated.

As a method of calculating the space volume V _r , for example, Boyle's law can be used. That is, it is possible to use a relationship in which the increase ΔP _s of the internal pressure when supplying the gas with the predetermined integrated supply amount Q ₁ is proportional to the amount of iron powder in the container 2 and inversely proportional to the space volume V _r . For example, the increase ΔP _smax of the internal pressure in the container 2 when the gas of the integrated supply amount Q ₁ is supplied to the space volume V _rmin in a state where the maximum weight (maximum volume) of iron powder is put in the container 2 is previously set. Check it out. Then, an integrated supply amount Q ₁ of gas is supplied into the container 2 that actually performs pressurization, and the internal pressure increase ΔP _s in the container 2 is measured by the pressure gauge 10. Then, the space volume V _r can be obtained from the relationship of V _r = ΔP _smax × V _rmin / ΔP _s .

  In addition, the control unit 6 is provided with a start switch 91 and an end switch 92 that can be switched between an ON state and an OFF state by an operator. When the start switch 91 is input to the ON state, automatic operation of the gas supply process under the control of the control unit 6 is started. When the end switch 92 is input to the ON state, the automatic operation of the gas supply process under the control of the control unit 6 is stopped.

Next, a gas supply method using the gas supply system 1 configured as described above will be described. First, the connection tool 15 is attached to the supply port 13a of the container 2 by the operator, and the on-off valve 7a is opened with the on-off valve 22 closed. And after iron powder is thrown in in the container 2 from the inlet / outlet 7, the on-off valve 7a is closed and the storage space 2a is sealed. Thus, when iron powder is thrown into the container 2, the inside of the container 2 is maintained in a state purged with a gas (for example, nitrogen gas N ₂ ), and the iron powder is not allowed to enter the container 2 without entering the atmosphere. Can be introduced into the inlet / outlet 7.

  In the sealed container 2 in which the iron powder is thus stored, the operator attaches the outlet end of the hose 3 to the inlet end of the connector 15. That is, the gas supply path 3 a is connected to the container 2 through the connection tool 15. When the hose 3 is attached to the connection tool 15, the opening / closing valve 22 is opened manually by the operator, and the inside of the container 2 and the gas supply path 3a are communicated. Then, the start switch 91 is turned on, and a command for starting the automatic operation is given to the control unit 6.

  When a command to start automatic operation is given, the control unit 6 first confirms whether the gas supply system 1 has a start condition, that is, whether there is an abnormality in the gas supply system 1 (step S1 in FIG. 3). . Specifically, for example, whether or not each of the on-off valves 47, 71, 73 is closed, and the measured values of the pressure gauge 10, the gas supply path pressure gauge 45, and the integrated flow meter 64 are within a predetermined range, respectively. It is judged whether it is in. The starting condition is satisfied (the on-off valves 47, 71, 73 are all closed, and the measured values of the pressure gauge 10, the gas supply path pressure gauge 45, and the integrated flow meter 64 are within predetermined ranges, respectively. If it is determined that there is, the next step S2 is executed. On the other hand, when it is determined that the activation condition is not satisfied, the control unit 6 gives a command for generating an alarm to the signal lamp 81 or the buzzer 82 (step S3). Accordingly, an alarm is generated by the signal lamp 81 or the buzzer 82, and the operator is notified by the alarm that there is an abnormality in the gas supply system 1.

  In step S2, the pressure measurement value of the pressure gauge 10 is detected by the control unit 6, and the control unit 6 determines whether or not the pressure measurement value (internal pressure of the container 2) is equal to or less than a predetermined set value. The When the measured pressure value is less than or equal to the set value, it is determined that the container 2 can be safely pressurized and the first gas supply step (step S4) is executed. On the other hand, when the pressure measurement value is higher than the set value, it is determined that the state is abnormal, and step S5 (see FIG. 5) for performing an emergency stop is executed. Step S5 will be described in detail later. Thus, before supplying gas into the container 2, it is possible to check whether the internal pressure in the container 2 is equal to or lower than the set value. Can be prevented. Therefore, it is possible to prevent the container 2 from being damaged due to excessive internal pressure generated in the container 2.

In the first gas supply step S4, a command to open the on-off valve 71 is given from the control unit 6. That is, the on-off valve 71 is opened while the on-off valve 73 is closed. As a result, the gas supplied from the gas supply source 48 passes through the main introduction path 50, the flow path 51, and the gas supply path 3a in this order, and is supplied into the container 2 at a high supply pressure _PS1 . While the gas is supplied at the supply pressure _PS1 , the control unit 6 detects the measurement value of the integrated flow meter 64 and monitors the integrated flow rate from the start of gas supply in the previous gas supply step S4. When the cumulative flow from the start of the supply of gas reaches a predetermined value Q _1, the control unit 6, an opening and closing valve 71 is closed giving instructions to stop the supply of gas. That is, the previous gas supply step S4 is terminated. Thus, by a predetermined cumulative supply quantity Q ₁ minute gas is supplied into the container 2, a state where the container 2 is pressurized than the previous year gas supply step S4.

When the first gas supply step S4 is completed, the internal pressure in the container 2 is measured by the pressure gauge 10, the pressure measurement value is detected by the control unit 6 (step S6), and the pressure measurement value is set to a predetermined target value in the control unit 6. It is determined whether or not it is greater than or _{equal to Pc2} (step S7). If the pressure measurement value is lower than the target value P _c2, it is determined that there is a need for further supply of gas, step S10 of calculating the following additional cumulative supply quantity Q ₂ is performed. On the other hand, when the pressure measurement value is equal to or greater than the target value _Pc2 , it is determined that it is not necessary to supply more gas, and step S11 is executed. In step S11, it is determined whether or not the pressure measurement value is within a normal value range. If the pressure measurement value is within the normal value range, the gas supply process is terminated normally, and step S24 of the pressure holding process described later is performed. (See FIG. 4) is executed. If it is not within the range of the normal value, it is determined that the pressure is excessively abnormal, and step S5 (see FIG. 5) for performing an emergency stop is executed.

In step S10, additional cumulative supply quantity Q ₂ for pressurized the pressure inside the container 2 to the target value P _c2 are calculated. That is, the calculation of the control unit 6 determines the space volume V _r in the container 2 from the integrated supply amount Q ₁ supplied in the previous gas supply step S4, and further calculates the additional integrated supply amount Q from the space volume V _{r. 2} is required. Then, the next late gas supply step (step S21, see FIG. 4) is executed.

In the late gas supply step S21, firstly, to supply at a first supply pressure P _S1 first late gas supply step S21a is performed a gas into the container 2, then, the second gas into the container 2 A second late gas supply step S21b that is supplied at the supply pressure P _S2 (P _S2 <P _S1 ) is performed.

In the first latter gas supply step S21a, a command to open the on-off valve 71 is given from the control unit 6, and the on-off valve 71 is opened while the on-off valve 73 is closed. As a result, the gas supplied from the gas supply source 48 passes through the main introduction path 50, the flow path 51, and the gas supply path 3a in this order, and is supplied into the container 2 at a high supply pressure _PS1 . While the gas is supplied at the supply pressure _PS1 , the control unit 6 detects the measurement value of the integrated flow meter 64, and monitors the integrated flow rate after the gas supply is started. When the integrated flow rate after starting the gas supply in the first latter gas supply step S21a reaches Q _2a (Q _2a <Q ₂ ), an instruction to close the on-off valve 71 is given to stop the gas supply. Let That is, the first late gas supply step S21a is terminated. Thus, given integration supply amount into the container 2 (first cumulative supply quantity) by Q _2a amount of gas is supplied, the container 2 is pressurized than the previous first late gas supply step S21a It becomes a state. The accumulated supply amount Q _2a of the gas supplied in the first latter gas supply step S21a may be a large amount of the additional integrated supply amount Q ₂ , for example, about 90%, for example, about 85% to It may be about 90% (Q _2a = 0.8Q _{2 to} 0.95Q ₂ ). The remaining integrated supply amount obtained by subtracting the cumulative supply quantity _{Q 2a} from the rest of the additional accumulated supply quantity _{Q 2} a (second cumulative supply _{quantity) Q 2b (Q 2b = Q} 2 -Q 2a), the following second It is preferable to supply in the latter gas supply step S21b.

When the first late gas supply step S21a is completed, the second late gas supply step S21b is then started. In the second late gas supply step S21b, a command to open the on-off valve 73 is given from the control unit 6, and the on-off valve 73 is opened while the on-off valve 71 is closed. As a result, the gas supplied from the gas supply source 48 passes through the main introduction path 50, the flow path 52, and the gas supply path 3a in this order, and is supplied into the container 2 at a low supply pressure _PS2 . While the gas is supplied at the supply pressure _PS2 , the control unit 6 detects the measurement value of the integrated flow meter 64, and monitors the integrated flow rate after the gas supply is started. The integrated flow from the start of the supply of gas in the second late gas supply step S21b is reached the Q _2b, the on-off valve 73 is closed giving instructions to stop the supply of gas. That is, the second late gas supply step S21b is finished and the late gas supply step S21 is finished. Thus, by a predetermined cumulative supply quantity Q _2b amount of gas is supplied into the container 2, more pressure than the previous container 2 has a second late gas supply step S21b, substantially pressure target value P _c2 Pressurize until.

As described above, by the first late gas supply step S21a and the second late gas supply step S21b is carried out, additional cumulative supply quantity Q ₂ of the gas calculated in step S10 in the container 2 is supplied The Then, the internal pressure in the container 2 substantially reaches the target value _Pc2 . According to the latter gas supply step S21, the majority of the additional accumulated supply quantity Q ₂ a (cumulative supply quantity Q _2a) By supplying a high pressure, quickly pressing the inside of the container 2, the later gas supply step S21 The time required can be shortened. Further, by supplying the remaining small amount (integrated supply amount Q _2b ) at a low pressure, the inside of the container 2 can be prevented from being excessively pressurized. That is, when the step of supplying at all additional cumulative supply quantity Q ₂ minutes of gas pressure, if when additional cumulative supply quantity Q ₂ there is an error in the calculation of the control unit 6 is larger amount calculated incorrectly that additional cumulative supply quantity Q ₂ by being excessively supplied at high pressure into the container 2, there is a risk that the container 2 or explode damaged, the cumulative supply quantity Q _2b minute to supply at low pressure , Such an accident can be prevented in advance. Therefore, the inside of the container 2 can be safely pressurized. As the cause of the error in the calculation of additional integrated supply quantity Q _2, errors in pressure measurements by the pressure gauge 10, error of the temperature measurement value by the thermometer 63 can be considered.

  When the second late gas supply step S21b is completed, the pressure measurement value of the pressure gauge 10 is measured, the internal pressure in the container 2 is detected by the control unit 6 (step S22), and the pressure measurement value is predetermined by the control unit 6. It is determined whether it is within the range (step S23). When the pressure measurement value is within the normal value range, it is determined as normal, and the next pressure holding step (step S24) is executed. On the other hand, when the pressure measurement value is not within the range of the normal value, it is determined that the pressure is excessively increased, and an emergency stop step S5 is executed.

  In the pressure holding step S24, the control unit 6 constantly monitors the pressure measurement value measured by the gas supply path pressure gauge 45, and the pressure measurement value of the gas supply path pressure gauge 45 has decreased below a predetermined set value. In this case, the on-off valve 73 is opened so that gas flows through the flow path 52 and the gas supply path 3a. If the pressure measurement value of the gas supply path pressure gauge 45 is higher than a predetermined set value, the on-off valve 73 is kept closed. Thus, by constantly monitoring the pressure measurement value of the gas supply path pressure gauge 45, the pressure measurement value of the gas supply path pressure gauge 45 decreases when the hose 3 is removed from the connector 15. Thus, it can be detected that the hose 3 has been removed from the connector 15. Further, in this case, it is possible to prevent the outside air from entering the gas supply path 3a from the outlet end of the gas supply path 3a by flowing the gas. Therefore, the gas supply path 3a, the flow paths 51 and 52, and the main introduction path 50 can be maintained in the purged state with the inert gas, and when the gas is supplied to the next container 2, the gas supply path 3a It is possible to prevent outside air from entering the container 2.

  Thus, the gas supply system 1 stands by while performing the pressure holding step S23 until the end switch 92 is turned on by the operator (step S25). When the operator confirms that the gas supply has been completed normally, the operator inputs the end switch 92 to the ON state. When the control unit 6 confirms that the end switch 92 has been input to the ON state, the automatic operation of the gas supply system 1 is stopped. As described above, a series of gas supply steps is completed.

  Next, step S5 for performing an emergency stop will be described. In step S <b> 5, the control unit 6 gives a command for generating an alarm to the signal lamp 81 or the buzzer 82. Accordingly, an alarm is generated by the signal lamp 81 or the buzzer 82, and the operator is notified by the alarm that there is an abnormality in the gas supply system 1. Further, the control unit 6 gives a command to close all the on-off valves 47, 71, 73. Thereafter, step S31 similar to the pressure holding step S24 is performed. The gas supply system 1 stands by while performing the pressure holding step S24 until the end switch 92 is turned on by the operator (step S32). The operator confirms that there is an abnormality, inspects each part, and then inputs the end switch 92 to the ON state. When the control unit 6 confirms that the end switch 92 has been input to the ON state, the automatic operation of the gas supply system 1 is stopped. As described above, the gas supply process is stopped.

According to the gas supply system 1, the gas can be automatically supplied into the container 2 under the control of the control unit 6. An excessive supply of gas into the container 2 can be prevented. After supplying the gas at the supply pressure _PS1 , the supply pressure is lowered to _PS2, and the overpressure in the container 2 and the breakage of the container 2 can be prevented, and automatic supply can be performed safely.

Further, predetermined the integrated supply quantity Q ₁ and add the integrated supply quantity Q _2, by determining the timing of the supply stop of gas on the basis of these cumulative supply quantity Q _1, Q _2, to ensure the container 2 pressure it can. For example, if an attempt is made to determine the timing of gas supply stop based on the elapsed time from the start of gas supply, it cannot cope with the case where the space volume V _r in the container 2 differs, and the internal pressure in the container 2 May not be accurately adjusted. In addition, when the opening of the filter 35 is different or when the filter 35 is clogged, the flow rate of the gas into the container 2 changes. There is a risk that the supply cannot be sufficiently performed. On the other hand, according to the gas supply system 1, the inside of the container 2 is accurately adjusted according to the space volume V _r in the container 2 regardless of the size of the opening of the filter 35 and the clogging state of the filter 35. Can be pressurized.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various changes and modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

For example, after step S2, before performing the year gas supply step S4, on the basis of the temperature measurements of the gas by the thermometer 63, the step of correcting the value of the integrated supply quantity Q ₁ is supplied with the previous term gas supply step S4 You may carry out. That is, as the temperature of the gas is low, may increase the cumulative supply quantity Q _1. Thus corrected cumulative supply quantity Q ₁ in accordance with the temperature of the gas can be supplied more gas in the previous term gas supply step S4. Therefore, the time required for the later gas supply step S21 performed later can be shortened, which is efficient.

  In the first gas supply step S4, the flow rate of the gas supplied to the gas supply path 3a is measured, and when the flow rate is not within a predetermined range, the gas supply may be stopped. For example, the control unit 6 detects the flow velocity of the gas in the main introduction path 50 from the measurement value of the integrated flow meter 64, and determines whether or not this flow velocity measurement value is within a predetermined range. When the flow rate is slower than the predetermined range, there is a possibility that gas supply is hindered by clogging of the filter 35 or the like. Further, when the flow velocity is faster than a predetermined range, for example, the hose 3 may be detached from the connector 15 or the hose 3 or the filter 35 may be damaged. Therefore, when the flow velocity is not within the predetermined range, it is preferable to execute step 5 by an instruction from the control unit 6 to generate an alarm and notify the operator.

In step S6, before the pressure measurement value by the pressure gauge 10 is detected, the on-off valve 47 may be opened by a command from the control unit 6, and the gas may be discharged from the gas supply path 3a by the discharge path 46. That is, the internal pressure in the container 2 can be measured more accurately by extracting gas from the gas supply path 3a and reducing the pressure in the gas supply path 3a. Thus, by measuring the following additional cumulative supply quantity Q ₂ more accurately, the container 2 can be suitably pressurized.

  In the second late gas supply step S21b, for example, the controller 6 detects and monitors the elapsed time, and according to the elapsed time since the second late gas supply step S21b is started, the second late gas supply step S21b is performed. Step S21b may be stopped. In other words, if the second late gas supply step S21b does not end within a predetermined elapsed time, there is a possibility that an abnormality such as clogging of the filter 35 has occurred and the gas supply is hindered. For this reason, it is preferable to execute step 5 according to a command from the control unit 6, stop the gas supply, generate an alarm, and notify the operator.

  In the above embodiment, the powder stored in the container 2 is iron powder, but the powder is not limited to this. Moreover, although nitrogen gas illustrated the gas, it is not limited to this, For example, inert gas, such as argon gas (Ar), may be sufficient.

The inventors of the present invention have determined an integrated supply amount Q _x of nitrogen gas necessary for pressurizing the inside of the container 2 having a volume V _c = 4000 [L] (4 [m ³ ]) to a predetermined internal pressure, and a gas equation of state Was used for estimation. The gas constant of nitrogen gas was R = 0.082 [L · atm / mol · K]. Further, 1 mol = 22.4 [L] was set.

(Estimation 1)
In an empty container 2 in which iron powder is not stored, when the gas temperature T _o = 273 [K] (0 ° C.), the internal pressure P _c in the container 2 is changed from 1 [atm] to 1.24 [atm. ] (0 [MPa] to 0.025 [MPa] (gauge pressure)).
The number of moles n _x1 of gas in the container 2 before pressurization is
n _x1 = P _c V _c / RT _o = 178.68 [mol]
Moles n _x2 of the gas in the container 2 after pressing,
_{n x2 = P c V c /} RT o = 221.57 [mol]
Therefore, the cumulative supply amount Q _x that must be supplied into the container 2 is
Q _x = n _x2 −n _x1 = 42.89 [mol] × 22.4 [L]
= 960.74 [L]
From the above, it can be seen that the internal pressure _Pc can be increased from 1 [atm] to 1.24 [atm] by supplying 960.74 [L] gas into the container 2.

(Estimation 2)
As in the trial calculation 1, in the empty container 2 in which the iron powder is not stored, when the gas temperature T _o = 313 [K] (40 ° C.), the internal pressure P _c in the container 2 is set to 1 [atm ] To 1.24 [atm], the number of moles of gas in the container 2 before pressurization n _x1 = 155.85 [mol], the number of moles after pressurization n _x2 = 193.25 From [mol], the cumulative supply amount Q _x that must be supplied into the container 2 is 837.76 [L].

(Trial calculation 3)
In the container 2 in which the iron powder is stored for the maximum storage volume V _p = 2500 [L], when the gas temperature T _o = 273 [K], the internal pressure P _c in the container 2 is set to 1 [atm ] To 1.24 [atm].
The number of moles n _x1 of gas in the container 2 before pressurization is
_{n x1 = P c (V c} -V p) / RT o = 67.01 [mol]
Moles n _x2 of the gas in the container 2 after pressing,
_{n x2 = P c (V c} -V p) / RT o = 83.09 [mol]
Therefore, the cumulative supply amount Q _x that must be supplied into the container 2 is
_{Q x = n x2 -n x1 =} 16.08 [mol] × 22.4 [L]
= 360.19 [L]
From the above, it can be seen that the internal pressure _Pc can be increased from 1 [atm] to 1.24 [atm] by supplying 360.19 [L] gas into the container 2.

(Estimation 4)
Similar to estimate 3, in volume _V p = 2500 container 2 iron powder is stored in [L], when the temperature _T o = 313 gas [K], the internal pressure _{P c} in the container 2, 1 When calculating from the case of increasing from [atm] to 1.24 [atm], the number of moles of gas in the container 2 before pressurization n _x1 = 58.44 [mol], From the number of moles n _x2 = 72.47 [mol], the integrated supply amount Q _x that must be supplied into the container 2 is 314.27 [L].

From the above trial calculations 1 to 4, in the container 2 having a volume of 4000 [L] and a maximum storage amount of iron powder of 2500 [L], at least about 300 [L] (0.3 [m ³ ]) or more gas It turns out that it is necessary to supply. In other words, if it is up to about 300 [L], it can be considered that the container 2 is not damaged even if it is supplied at a relatively high supply pressure, and can be safely supplied with a margin. Further, it is understood that it is efficient if an additional integrated supply amount to be added is calculated after supplying about 300 [L] of gas. For example, the integrated supply amount Q1 in the _first- stage gas supply step S4 of the present embodiment may be about 300 [L], and then the additional integrated supply amount Q2 is calculated and added in the _second- stage gas supply step S21. It is thought that it should be supplied.

(Example)
The total volume _{V c} of the container 2 to about 4000 [L], the maximum storage amount of the iron powder was about 2500 [L], the target value _{P c} of the internal pressure in the container 2 to about 0.02 [MPa] to 0.025 [MPa] (gauge pressure). In year gas supply step S4, the integrated supply quantity _{Q 1} is set to about 300 [L], the supply pressure of the gas is about 0.5 [MPa]. In the first late gas supply step S21a, the integrated supply quantity _{Q 2a} is about 0.8Q ₂ ~0.95Q _2, the first supply pressure _{P S1} is about 0.5 [MPa]. In a second late gas supply step S21b, cumulative supply quantity _{Q 2b} was approximately 0.15Q ₂ ~0.2Q _2, the second supply pressure _{P S2} is approximately 0.03 [MPa]. Thereby, the inside of the container 2 can be safely pressurized.

  The present invention can be applied to a gas supply system and a gas supply method for supplying gas to a container and adjusting the internal pressure to a desired value.

It is explanatory drawing which showed the structure of the system for gas supply concerning this Embodiment. It is the fragmentary sectional view which showed the structure of the connection cylinder and the connection tool. It is a flowchart of a gas supply method. It is a flowchart of a gas supply method. It is a flowchart of a gas supply method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas supply system 2 Container 3a Gas supply path 5 Supply pressure adjustment mechanism 6 Control part 10 Pressure gauge 50 Main introduction path 51 1st flow path 52 2nd flow path 64 Integrated flowmeter 71,73 On-off valve

Claims (11)

A system for supplying gas to a container for storing powder,
A gas supply path for supplying gas into the container;
A supply pressure adjusting mechanism for switching the supply pressure of the gas supplied into the container by the gas supply path;
A control unit for controlling the supply pressure adjusting mechanism,
The control unit supplies the gas into the container at a first supply pressure, and then sets the gas supply pressure to a second supply pressure lower than the first supply pressure, A system for supplying gas to a container, wherein control is performed to supply the gas into the container until a predetermined internal pressure is reached. The control unit detects a spatial volume obtained by subtracting the volume of the powder stored in the container from the total volume in the container based on an integrated supply amount of the gas supplied into the container and an internal pressure in the container. The system for supplying gas to a container according to claim 1, comprising a function and a function of calculating an additional integrated supply amount required to pressurize the internal pressure of the space volume to a predetermined value. The supply pressure adjusting mechanism includes a main introduction path that supplies the gas under pressure from a gas supply source, and a first flow that supplies the gas from the main introduction path to the gas supply path at the first supply pressure. And a second flow path for supplying the gas from the main introduction path to the gas supply path at the second supply pressure,
The first flow path is provided with a first on-off valve for communicating and blocking the first flow path,
The second flow path includes a pressure regulating valve that reduces the supply pressure of the gas passing through the second flow path to the second supply pressure, and a second flow path that connects and blocks the second flow path. The system for supplying gas to a container according to claim 1 or 2, wherein an on-off valve is provided. The system for supplying gas to a container according to any one of claims 1 to 3 , further comprising an integrated flow meter for measuring an integrated flow rate of gas supplied to the gas supply path. The system for supplying gas to a container according to any one of claims 1 to 4, further comprising a pressure gauge for measuring an internal pressure in the container. A method of supplying gas to a container for storing powder,
Supplying the gas into the container at a first supply pressure;
Thereafter, the gas supply pressure is set to a second supply pressure lower than the first supply pressure, the gas is supplied into the container, and the inside of the container is set to a predetermined internal pressure, Gas supply method to the container. Before supplying the gas at the first supply pressure, supplying the gas into the container;
Then measure the internal pressure in the container,
Calculate the volume of space obtained by subtracting the volume of the powder stored in the container from the total volume in the container from the integrated supply amount supplied into the container and the measured internal pressure.
From the space volume, an additional integrated supply amount required to pressurize the container to the predetermined internal pressure is obtained,
A first integrated supply amount of the additional integrated supply amount is supplied at the first supply pressure;
The gas supply to the container according to claim 6, wherein a second integrated supply amount obtained by subtracting the first integrated supply amount from the additional integrated supply amount is supplied at the second supply pressure. Method. 8. The method according to claim 7, wherein before measuring the internal pressure in the container, the gas is discharged from a gas supply path that supplies gas into the container, and the pressure in the gas supply path is reduced. Gas supply method to the container. 9. The apparatus according to claim 6, wherein when the flow rate of the gas supplied into the container is not within a predetermined range, the supply of the gas into the container is stopped and an alarm is generated. The gas supply method to the container of description. The supply of the gas into the container is stopped and the alarm is generated when the supply by the second supply pressure does not end within a predetermined elapsed time. The gas supply method to the container of description. The gas is supplied to the gas supply path when the pressure in the gas supply path for supplying the gas into the container is lowered after the supply by the second supply pressure is completed. The gas supply method to the container in any one of -10.

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