JP5633439B2 - Compressed air supply device - Google Patents

Description

  The present invention relates to a compressed air supply apparatus.

  2. Description of the Related Art Conventionally, for example, in a production factory for various products such as a personal computer (PC), a mobile phone, and the like, a plurality of facilities (air devices) that are operated by compressed air are arranged. Air equipment is used for operation of mounting equipment, assembly equipment, and the like because of its ease of control. The compressed air that drives the air device is produced by a compressor and is supplied to each air device through a pipe of several tens to several hundreds of meters. At this time, the pressure decreases as it goes to the end of the pipe far from the compressor. If the pressure falls, it will cause malfunction of equipment operation, equipment stoppage and malfunction. In order to avoid such inconvenience and to secure the operating pressure of each air device by securing the end pressure, the pressure of the compressed air produced by the compressor is set high in advance in the conventional equipment. As a result, in the conventional equipment, the amount of electric power (energy amount) for operating the compressor has also increased.

  In view of such a situation, a proposal has been made to reduce wasteful energy consumption in a compressed air supply facility and contribute to energy saving (for example, Patent Document 1). Patent Document 1 discloses a compressed air supply facility in which a sub compressor and a sub tank are installed on the end side of an air supply pipe in which a main compressor and a main tank are arranged on one end side. This compressed air supply facility reduces the pressure supplied by the main compressor by preventing the pressure drop on the end side.

JP 2003-65498 A

  However, even with the compressed air supply equipment proposed in Patent Document 1, a local pressure drop may occur. For example, when a large amount of air is consumed in a short time (for example, about several seconds) in a facility away from the compressor, a pressure drop may occur instantaneously and locally. In addition, such a momentary and local drop in pressure also affects adjacent air equipment, which may cause an operation stop or malfunction.

  Therefore, a compressed air supply facility disclosed in the present specification is intended to cope with an instantaneous and local pressure drop.

  The compressed air supply device disclosed in this specification includes a first compressed air supply unit, a main pipe through which the air compressed by the first compressed air supply unit flows, a branch from the main pipe, and the use of the air A branch pipe to which the working machine that operates in this way is connected; an auxiliary pipe that joins the branch pipe; a second compressed air supply means that pumps air to the auxiliary pipe; and a pressure of air that circulates in the branch pipe. A pressure sensor for measuring, a flow path switching means for changing the air flow state of the branch pipe and the auxiliary pipe, and a control unit for operating the flow path switching means based on information acquired by the pressure sensor, Prepare.

  The working machine, that is, the air device is driven by the air supplied by the first compressed air supply means at the normal time when the pressure in the main pipe has a margin. For example, when a large amount of compressed air is used in the air device or another adjacent air device, when the pressure drops instantaneously or locally, the air device It is driven by the air supplied by the air supply means. In this way, by supplementing the first compressed air supply means with the second compressed air supply means, it is possible to set a small margin for the first compressed air supply means. As a result, wasteful energy consumption can be suppressed.

  According to the compressed air supply device disclosed in the present specification, it is possible to cope with an instantaneous and local pressure drop.

FIG. 1 is an explanatory diagram illustrating a schematic configuration of a compressed air supply apparatus according to a first embodiment. FIG. 2 is a flowchart illustrating an example of control of the compressed air supply device according to the first embodiment. FIG. 3 is a time chart illustrating an example of the operation of the compressed air supply device according to the first embodiment. FIG. 4 is an explanatory diagram illustrating a schematic configuration of the compressed air supply device according to the second embodiment. FIG. 5 is a flowchart illustrating an example of control of the compressed air supply device according to the second embodiment. FIG. 6 is a time chart illustrating an example of the operation of the compressed air supply device according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, in the drawings, the dimensions, ratios, and the like of each part may not be shown so as to completely match the actual ones.

  First, a schematic configuration of a compressed air supply device (hereinafter simply referred to as a “supply device”) 100 according to a first embodiment will be described with reference to FIG.

  The supply apparatus 100 includes a compressor 20 as first compressed air supply means. The supply device 100 includes a main pipe TU0 and a first branch pipe TU1, a second branch pipe TU2, and a third branch pipe TU3 that branch from the main pipe TU0. The number of branch pipes is not limited to three.

  The compressor 20 is connected to the main pipe TU0. The main pipe TU0 is a loop pipe. Air fed by the compressor 20 flows through the main pipe TU0. Since the main pipe TU0 is a loop pipe, it is easy to maintain a uniform pressure over the entire circumference. Normally, the pressure in the pipe tends to decrease as the distance from the compressor 20 increases, but the pressure gradient in the main pipe TU0 can be reduced by using a loop-shaped pipe.

  The first branch pipe TU1, the second branch pipe TU2, and the third branch pipe TU3 branched from the main pipe TU0 include a first air device M1, a second air device M2, and a second air device M2, which are working machines that operate using air. Three air devices M3 are connected to each other. Examples of the air equipment include a bending machine and a press equipped with an air cylinder, a vacuum generator for sucking and moving parts and products, and an air blower.

  The first auxiliary pipe TU11 joins the first branch pipe TU1 at the first joining point P1. Similarly, the second auxiliary pipe TU21 joins the second branch pipe TU2 at the second joining point P2, and the third auxiliary pipe TU31 joins the third branch pipe TU3 at the third joining point P3. ing.

  The supply device 100 includes a first pressure accumulation tank T1 that is an example of a second compressed air supply unit that pressure-feeds air to the auxiliary pipe TU11, the auxiliary pipe TU21, and the auxiliary pipe TU31. The first accumulator tank T <b> 1 is supplied with compressed air from the compressor 20. Specifically, the supply apparatus 100 includes a first pressure accumulation tank T1 connected to the main pipe TU0 via a first tank connection pipe TU101. The first tank connection pipe TU101 includes a first tank control valve VT1 corresponding to a tank control valve that controls the inflow of air from the main pipe TU0 to the first pressure accumulation tank T1. A first auxiliary pipe TU11, a second auxiliary pipe TU21, and a third auxiliary pipe TU31 are connected to the first pressure accumulation tank T1. The first pressure accumulation tank T1 is provided with a first tank pressure sensor ST1 that measures the pressure inside the first pressure accumulation tank T1.

  The supply device 100 includes a pressure sensor for measuring the pressure of air flowing through each branch pipe in each branch pipe. Specifically, the supply device 100 includes a first pressure sensor S1 that measures the pressure of the air flowing through the first branch pipe TU1. In addition, the supply device 100 includes a second pressure sensor S2 that measures the pressure of air flowing through the second branch pipe TU2, and a third pressure sensor S3 that measures the pressure of air flowing through the third branch pipe TU3. . The first pressure sensor S1 is disposed between the first junction P1 and the first air device M1. The second pressure sensor S2 is disposed between the second junction P2 and the second air device M2. The third pressure sensor S3 is disposed between the third junction P3 and the third air device M3.

  The supply apparatus 100 includes a flow path switching unit that changes the air circulation state of the branch pipe and the auxiliary pipe. The flow path switching means for the first branch pipe TU1 specifically includes a first control valve V1 that controls the flow of air in the first branch pipe TU1, and a first auxiliary that controls the flow of air in the first auxiliary pipe TU11. And a valve V11. The flow path switching means for the second branch pipe TU2 specifically includes a second control valve V2 that controls the flow of air in the second branch pipe TU2, and a second auxiliary that controls the flow of air in the second auxiliary pipe TU21. And a valve V21. Further, the flow path switching means for the third branch pipe TU3 specifically includes a third control valve V3 that controls the flow of air in the third branch pipe TU3 and a third control valve that controls the flow of air in the third auxiliary pipe TU31. 3 auxiliary valves V31.

  The first control valve V1 and the first auxiliary valve V11 are respectively disposed upstream of the first junction P1. The second control valve V2 and the second auxiliary valve V21 are respectively disposed upstream of the second junction P2. The third control valve V3 and the third auxiliary valve V31 are respectively disposed upstream of the third junction point P3.

  The supply apparatus 100 includes a control unit 10 that operates the first control valve V1 and the first auxiliary valve V11 based on information acquired by the pressure sensor, that is, the first pressure sensor S1. The control unit 10 operates the second control valve V2 and the second auxiliary valve V21 based on the information acquired by the second pressure sensor S2. Further, the third control valve V3 and the third auxiliary valve V31 are operated based on the information acquired by the third pressure sensor S3.

  The control unit 10 is electrically connected to each pressure sensor, each control valve, each auxiliary valve, and each air device, and performs integrated control of the supply device 100.

  Next, the operation of the supply apparatus 100 as described above will be described with reference to the flowchart shown in FIG. 2 and the time chart shown in FIG. First, the initial state before the control is started will be described. In the initial state, the first tank control valve VT1 is closed. In addition, it is assumed that the pressure in the main pipe TU0, other branch pipes, and the first pressure accumulation tank T1 when each air device is not operating is set to 0.6 MPa. In addition, in the following description, in order to simplify description, it demonstrates centering on control in 1st branch pipe TU1 and 1st auxiliary pipe TU11 when the 1st air apparatus M1 act | operates. In practice, each air device operates separately, and pressure fluctuations occur in each branch pipe. At this time, each branch pipe influences each other, and the control unit 10 controls each branch pipe.

  First, when the operation of the first air device M1 starts at time t1, the pressure (S1) in the first branch pipe TU1 starts to decrease. In step S01, the control unit 10 determines whether or not the pressure S1 is less than 0.5 MPa. Here, the pressure value of 0.5 MPa is an operation threshold value of the first control valve V1 and the first auxiliary valve V11 included in the flow path switching means, and can be arbitrarily set. The pressure value 0.4 MPa is an operation guarantee value of the first air device M1.

  When S1 falls below the pressure value of 0.5 MPa at time t2 and it is determined Yes in step S01, the process proceeds to steps S02 and S03. In step S02, the first auxiliary valve V11 is opened. As a result, compressed air is supplied from the first pressure accumulation tank T1 to the first air device M1 through the first auxiliary pipe TU11. As a result, the pressure S1 starts to rise. In the time chart shown in FIG. 3, the first branch pipe pressure indicated by a broken line indicates a case where no measures are taken when the pressure drops instantaneously and locally. For example, when a large amount of air is consumed at the same time as the adjacent second air device M2, there is a possibility that the operation guaranteed value is less than 0.4 MPa. By opening the first auxiliary valve V11, it is avoided that the pressure drops below 0.4 MPa. In step S03, the first control valve V1 is closed. This is because if the first control valve V1 remains open, the compressed air supplied through the first auxiliary pipe TU11 flows back to the first branch pipe TU1 through the first junction P1. This is to avoid the problem. That is, the system in which the compressed air is supplied through the main pipe TU0 and the first branch pipe TU1 is shut off, and is disconnected from the system in which the compressed air is supplied from the first pressure accumulation tank T1. Thereby, the pressure more than an operation guarantee value is stably securable. The first control valve V1 is preferably closed after the first auxiliary valve V11 is opened. This is because if the first control valve V1 is closed prior to the opening of the first auxiliary valve V11, a timing at which compressed air is not supplied to the first air device M1 occurs.

  In step S04, which is performed subsequent to step S03, it is determined whether or not the pressure value ST1 indicated by the first tank pressure sensor ST1 has fallen below the pressure value of 0.58 MPa. When the first auxiliary valve V11 is opened, the pressure ST1 in the first pressure accumulation tank T1 starts to decrease. The pressure value of 0.58 MPa is a threshold value for starting refilling of the pressure in the first pressure accumulation tank T1. When it is determined No in step S04, the process proceeds to step S06. When it is determined Yes in step S04, the process proceeds to step S05.

  When ST1 falls below the pressure value of 0.58 MPa at time t3, the first tank control valve VT1 is opened (step S05). At this time, the first tank control valve VT1 does not open at once, but gradually increases the opening. The reason for gradually opening the first tank control valve VT1 in this way is that when the first tank control valve VT1 is opened at once, the first pressure accumulation tank T1 and the main pipe TU0 become one path. The intention is to avoid this. Since the pressure supply from the first pressure accumulation tank T1 is performed when the pressure of the first branch pipe TU1 branched from the main pipe TU0 decreases, the main pipe TU0 and the first pressure accumulation tank T1 are basically separated. I want to keep it. However, if the pressure drop in the first pressure accumulation tank T1 becomes large, there is a possibility that a delay occurs in the response after the pressure is supplied from the first pressure accumulation tank T1. Therefore, although it is gradually, the intention is to replenish the pressure in the first pressure accumulation tank T1. When the first tank control valve VT1 starts to open, the rate of decrease of the pressure ST1 in the first pressure accumulation tank T1 becomes moderate.

  In step S06, which is performed subsequent to step S05 or step S04, it is determined whether or not the pressure value of the first pressure sensor S1 has exceeded 0.53 MPa. That is, it is determined whether or not the pressure value of the first pressure sensor S1 has returned as a result of receiving pressure supply from the first pressure accumulation tank T1. Here, the pressure value of 0.53 MPa is an example of a threshold value for determining the return of pressure.

  When the pressure value S1 exceeds the pressure value of 0.53 MPa at time t4, it is determined Yes in step S06, and the process proceeds to steps S07 and S08. When it is determined No in step S06, the process returns to step S04. In step S07, the first control valve V1 is opened. Thereby, the pressure S1 of the first branch pipe TU1 rapidly returns to 0.6 MPa. In the first embodiment, the drive of the first air device M1 is stopped at this timing, and the amount of air used temporarily becomes zero. In step S08, the first auxiliary valve V11 is closed. As a result, the first branch pipe TU1 returns to a state where only the pressure from the main pipe TU0 is supplied. The first auxiliary valve V11 is preferably closed after the first control valve V1 is opened. This is because if the first auxiliary valve V11 is closed prior to the opening of the first control valve V1, a timing at which compressed air is not supplied to the first air device M1 occurs.

  In step S09, which is performed subsequent to step S08, it is determined whether or not the value of the first tank pressure sensor ST1 exceeds the pressure value of 0.59 MPa. That is, it is determined whether or not the first tank control valve VT1 is opened and the pressure in the first pressure accumulation tank T1 is restored. Here, the determination threshold is set to 0.59 MPa instead of 0.6 MPa because the delay until the pressure actually increases to 0.6 MPa after the first tank control valve VT1 is activated is taken into consideration. is there. This pressure value can be set arbitrarily.

  If the pressure value ST1 exceeds 0.59 MPa at time t5, it is determined Yes in step S09, and the process proceeds to step S10. On the other hand, if it is determined No in step S09, the process in step S09 is repeated. In step S10, the first tank control valve VT1 is closed. Thereby, the supply apparatus 100 returns to the initial state.

  As described above, the supply device 100 is immediately supplied with pressure from the first pressure accumulation tank T1 through the auxiliary pipe even when the pressure in the branch pipe branched from the main pipe TU0 decreases. Thereby, even if it is a case where a pressure falls instantaneously and locally, the pressure more than the operation guarantee value of an air equipment can be maintained. For example, even if a large amount of air is consumed in a short time due to the operating status of one of the air devices, the pressure supplied to other air devices, particularly adjacent air devices, is reduced. The decrease can be suppressed. That is, according to the supply device of the first embodiment, it is possible to cope with an instantaneous and local pressure drop. Moreover, since the pressure fluctuation of each pipe provided in the supply device 100 is reduced, the discharge pressure of the compressor 20 can be set low, that is, the margin can be set low and the consumption energy of the compressor can be reduced. be able to.

  In order to cope with a momentary and local pressure drop, it is conceivable to reduce the pressure fluctuation by installing a pressure accumulation tank in the vicinity of each air device. However, if a pressure accumulation tank is installed for each air device, a wide tank installation space is required. If it is the supply apparatus 100 of Example 1, the pressure accumulation tank for every air equipment is unnecessary, and it is advantageous also in terms of space.

  Next, Example 2 will be described with reference to FIGS. The supply device 200 of the second embodiment and the supply device 1 of the first embodiment are common in that the main pipe TU0, the compressor 20 connected to the main pipe TU0, and the control unit 10 are provided, but are different in the following points. The supply device 200 includes a fourth branch pipe TU4, a fifth branch pipe TU5, and a sixth branch pipe TU6 in addition to the first branch pipe TU1, the second branch pipe TU2, and the third branch pipe TU3. A fourth air device M4 is connected to the fourth branch pipe TU4. A fifth air device M5 is connected to the fifth branch pipe TU5. A sixth air device M6 is connected to the sixth branch pipe TU6.

  Further, the supply device 200 includes a fourth auxiliary pipe TU41 that joins the fourth branch pipe TU4 at the fourth joining point P4, a fifth auxiliary pipe TU51 that joins the fifth branch pipe TU5 at the fifth joining point P5, and a sixth joining point. A sixth auxiliary pipe TU61 that joins the sixth branch pipe TU6 at a point P6 is provided. A fourth pressure sensor S4 is provided between the fourth junction P4 and the fourth air device M4. A fifth pressure sensor S5 is provided between the fifth junction P5 and the fifth air device M5. A sixth pressure sensor S6 is provided between the sixth junction P6 and the sixth air device M6.

  A fourth control valve V4 is provided upstream of the fourth junction TU4 in the fourth branch pipe TU4. A fourth auxiliary valve V41 is provided upstream of the fourth junction point P4 of the fourth auxiliary pipe TU41. A fifth control valve V5 is provided on the upstream side of the fifth junction TU5 from the fifth junction P5. A fifth auxiliary valve V51 is provided on the upstream side of the fifth merging point P5 of the fifth auxiliary pipe TU51. A sixth control valve V6 is provided on the upstream side of the sixth junction TU6 from the sixth junction P6. A sixth auxiliary valve V61 is provided on the upstream side of the sixth auxiliary pipe TU61 from the sixth junction P6.

  The supply device 200 further includes a second pressure accumulation tank T2 which is an example of a second compressed air supply unit that pressure-feeds air to the auxiliary pipe TU41, the auxiliary pipe TU51, and the auxiliary pipe TU61. Compressed air is supplied from the compressor 20 to the second pressure accumulation tank T2. Specifically, the supply apparatus 200 includes a second pressure accumulation tank T2 connected to the main pipe TU0 via the second tank connection pipe TU102. The second tank connection pipe TU102 includes a second tank control valve VT2 corresponding to a tank control valve that controls the inflow of air from the main pipe TU0 to the second pressure accumulation tank T2. A fourth auxiliary pipe TU41, a fifth auxiliary pipe TU51, and a sixth auxiliary pipe TU61 are connected to the second pressure accumulation tank T2. The second pressure accumulation tank T2 is provided with a second tank pressure sensor ST2 that measures the internal pressure.

  The first pressure accumulation tank T1 and the second pressure accumulation tank T2 are connected by a tank communication pipe TU110. The tank communication pipe TU110 is provided with a tank communication control valve VVT1.

  Thus, the supply device 200 has a configuration in which two supply devices 100 of the first embodiment are combined and the first heat storage tank T1 and the second heat storage tank T2 are connected by the tank communication pipe TU110. However, the main pipe TU0, which is a loop pipe of the supply device 200, includes a short-circuit TU120. The short-circuit TU120 is a pipe that is short-circuited in the middle of the loop of the main pipe TU0. The short-circuit TU120 is effective for reducing the pressure gradient in the main pipe TU0 as much as possible. In the second embodiment, one short-circuit tube is provided. However, it is also possible to arrange a larger number of short-circuit tubes and construct a mesh-like piping route.

  The control unit 10 included in the supply device 200 is electrically connected to each pressure sensor, each control valve, each auxiliary valve, and each air device, and performs integrated control of the supply device 200. This is the same as in the case of the first embodiment. In addition, about the element which is common in the supply apparatus 100 of Example 1, the same reference number is attached | subjected in drawing, The detailed description is abbreviate | omitted.

  Next, the operation of the supply apparatus 200 as described above will be described with reference to the flowchart shown in FIG. 5 and the time chart shown in FIG. First, the initial state before the control is started will be described. In the initial state, the first tank control valve VT1, the second tank control valve VT2, and the tank communication control valve VTT1 are closed. In addition, it is assumed that the pressure in the main pipe TU0, other branch pipes, the first pressure accumulation tank T1, and the second pressure accumulation tank T2 when each air device is not operating is set to 0.6 MPa. In addition, in the following description, in order to simplify description, it demonstrates centering on control in 1st branch pipe TU1 and 1st auxiliary pipe TU11 when the 1st air apparatus M1 act | operates. In practice, each air device operates separately, and pressure fluctuations occur in each branch pipe. At this time, each branch pipe influences each other, and the control unit 10 controls each branch pipe.

  First, when the operation of the first air device M1 starts at time t11, the pressure (S1) in the first branch pipe starts to decrease. In step S11, the controller 10 determines whether or not the pressure S1 is less than 0.5 MPa. Here, the pressure value of 0.5 MPa is an operation threshold value of the first control valve V1 and the first auxiliary valve V11 included in the flow path switching means, and can be arbitrarily set. The pressure value 0.4 MPa is an operation guarantee value of the first air device M1.

  When S1 falls below 0.5 MPa at time t12 and it is determined Yes in step S11, the process proceeds to step S12 and step S13. In step S12, the first auxiliary valve V11 is opened. As a result, compressed air is supplied from the first pressure accumulation tank T1 to the first air device M1 through the first auxiliary pipe TU11. As a result, the pressure S1 starts to rise. When the first auxiliary valve V11 is opened, it is avoided that the pressure is less than 0.4 MPa, which is the operation guarantee value of the air device M1. In step S13, the first control valve V1 is closed. This is because if the first control valve V1 remains open, the compressed air supplied through the first auxiliary pipe TU11 flows back to the first branch pipe TU1 through the first junction P1. This is to avoid the problem. That is, the system in which the compressed air is supplied through the main pipe TU0 and the first branch pipe TU1 is shut off, and is disconnected from the system in which the compressed air is supplied from the first pressure accumulation tank T1. Thereby, the pressure more than an operation guarantee value is stably securable. The first control valve V1 is preferably closed after the first auxiliary valve V11 is opened. This is because if the first control valve V1 is closed prior to the opening of the first auxiliary valve V11, a timing at which compressed air is not supplied to the first air device M1 occurs.

  In step S14 performed subsequent to step S13, it is determined whether or not the pressure value ST1 indicated by the first tank pressure sensor ST1 has fallen below the pressure value of 0.58 MPa. When the first auxiliary valve V11 is opened, the pressure ST1 in the first pressure accumulation tank T1 starts to decrease. The pressure value of 0.58 MPa is a threshold value for starting refilling of the pressure in the first pressure accumulation tank T1. When it is determined No in step S14, the process proceeds to step S20. When it is determined Yes in step S14, the process proceeds to step S15.

  When ST1 falls below a pressure value of 0.58 MPa at time t13, the first tank control valve VT1 is opened (step S15). At this time, the first tank control valve VT1 does not open at once, but gradually increases the opening. The reason for gradually opening the first tank control valve VT1 in this way is that when the first tank control valve VT1 is opened at once, the first pressure accumulation tank T1 and the main pipe TU0 become one path. The intention is to avoid this. Since the pressure supply from the first pressure accumulation tank T1 is performed when the pressure of the first branch pipe TU1 branched from the main pipe TU0 decreases, the main pipe TU0 and the first pressure accumulation tank T1 are basically separated. I want to keep it. However, if the pressure drop in the first pressure accumulation tank T1 becomes large, there is a possibility that a delay occurs in the response after the pressure is supplied from the first pressure accumulation tank T1. Therefore, although it is gradually, the intention is to replenish the pressure in the first pressure accumulation tank T1. When the first tank control valve VT1 starts to open, the rate of decrease of the pressure ST1 in the first pressure accumulation tank T1 becomes moderate.

  In step S16 performed subsequent to step S15, it is determined whether or not the pressure value of the first tank pressure sensor ST1 has fallen below 0.53 MPa. That is, it is determined whether or not the pressure in the first pressure accumulation tank T1 continues to decrease as a result of the first pressure accumulation tank T1 continuing to supply pressure to the first air device M1. Here, the pressure value of 0.53 MPa is an example of a threshold value for determining whether the pressure continues to decrease.

  If the pressure value ST1 falls below the pressure value 0.53 MPa at time t14, it is determined Yes in step S16, and the process proceeds to step S17. When it is determined No in step S16, the process proceeds to step S20. In step S17, the tank communication control valve VVT1 is opened. Thereby, the 1st pressure accumulation tank T1 and the 2nd pressure accumulation tank T2 will be in a communication state. As a result, the pressure ST1 in the first pressure accumulation tank T1 starts to increase, while the pressure ST2 in the second pressure accumulation tank T2 starts to decrease.

  In step S18, which is performed subsequent to step S17, it is determined whether or not the pressure value ST2 indicated by the second tank pressure sensor ST2 has fallen below the pressure value of 0.58 MPa. As the tank communication control valve VVT1 is opened, the pressure ST2 in the second pressure accumulation tank T2 starts to decrease. The pressure value of 0.58 MPa is a threshold value for starting the replenishment of the pressure in the second pressure accumulation tank T2. When it is determined No in step S18, the process proceeds to step S20. When it is determined Yes in step S18, the process proceeds to step S19.

  When ST2 falls below the pressure value of 0.58 MPa at time t15, the second tank control valve VT2 is opened (step S19). At this time, the second tank control valve VT2 is not opened all at once, but gradually increases in opening. The reason for gradually opening the second tank control valve VT2 in this way is that when the second tank control valve VT2 is opened at once, the twelfth pressure tank T2 and the main pipe TU0 become one path. The intention is to avoid this. Since the pressure supply from the second pressure accumulation tank T2 is performed when the pressure of the first branch pipe TU1 branched from the main pipe TU0 decreases, basically, the main pipe TU0 and the second pressure accumulation tank T2 are separated. I want to keep it. However, if the pressure drop in the second pressure accumulation tank T2 becomes large, there is a possibility that a delay occurs in the response after the pressure is supplied from the second pressure accumulation tank T2. Therefore, although it is gradually, the intention is to replenish the pressure in the second pressure accumulation tank T2.

  In step S20 performed subsequent to step S19 or steps S14, S16, and S18, it is determined whether or not the pressure value of the first pressure sensor S1 has exceeded 0.53 MPa. That is, it is determined whether or not the pressure value of the first pressure sensor S1 has returned as a result of receiving pressure supply from the first pressure accumulation tank T1 and further from the second pressure accumulation tank T2. Here, the pressure value of 0.53 MPa is an example of a threshold value for determining the return of pressure.

  If the pressure value S1 exceeds the pressure value 0.53 MPa at time t16, it is determined Yes in step S20, and the process proceeds to step S21 and step S22. When it is determined No in step S20, the process returns to step S14. In step S21, the first control valve V1 is opened. Thereby, the pressure S1 of the first branch pipe TU1 rapidly returns to 0.6 MPa. In the second embodiment, the driving of the first air device M1 is stopped at this timing, and the amount of air used temporarily becomes zero. In step S22, the first auxiliary valve V11 is closed. As a result, the first branch pipe TU1 returns to a state where only the pressure from the main pipe TU0 is supplied. The first auxiliary valve V11 is preferably closed after the first control valve V1 is opened. This is because if the first auxiliary valve V11 is closed prior to the opening of the first control valve V1, a timing at which compressed air is not supplied to the first air device M1 occurs.

  In step S23 performed subsequent to step S22, the tank communication control valve VTT1 is closed. Thereby, the communication between the first pressure accumulation tank T1 and the second pressure accumulation tank T2 is blocked. The processing in step S22 may be performed simultaneously with the measures in step S21 or S22, or prior to these measures.

  By closing the first auxiliary valve V11, the pressure ST1 in the first pressure accumulation tank T1 starts to increase. Further, when the tank communication control valve VTT1 is closed, the pressure ST2 in the second pressure accumulation tank T2 starts to increase.

  In step S24 performed subsequent to step S23, it is determined whether or not the value of the first tank pressure sensor ST1 exceeds the pressure value of 0.59 MPa. That is, it is determined whether or not the first tank control valve VT1 is opened and the pressure in the first pressure accumulation tank T1 is restored. Here, the determination threshold is set to 0.59 MPa instead of 0.6 MPa because the delay from when the first tank control valve VT1 is activated until the pressure actually increases to 0.6 MPa is taken into account. is there. This pressure value can be set arbitrarily.

  If the pressure value ST1 exceeds the pressure value 0.59 MPa at time t17, it is determined Yes in step S24, and the process proceeds to step S25. On the other hand, if it is determined No in step S24, the process of step S24 is repeated. In step S25, the first tank control valve VT1 is closed. In the second embodiment, in consideration of the reaction speed of the first tank control valve VT1 and the pressure increase rate, the valve closing command is issued slightly after time t17. This delay time can be adjusted.

  In step S26 performed subsequent to step S25, it is determined whether or not the value of the second tank pressure sensor ST2 has exceeded the pressure value of 0.59 MPa. That is, it is determined whether the second tank control valve VT2 is opened and the pressure in the second pressure accumulation tank T2 is restored. Here, the determination threshold is set to 0.59 MPa instead of 0.6 MPa because the delay until the pressure actually increases to 0.6 MPa after the first tank control valve VT2 is activated is taken into consideration. is there. This pressure value can be set arbitrarily.

  When the pressure value ST2 exceeds the pressure value of 0.59 MPa at time t18, it is determined Yes in step S26, and the process proceeds to step S27. On the other hand, if it is determined No in step S26, the process of step S26 is repeated. In step S27, the second tank control valve VT2 is closed. As a result, the supply device 200 returns to the initial state. In the second embodiment, in consideration of the reaction speed of the first tank control valve VT1 and the pressure increase rate, the valve closing command is issued slightly after time t18. This delay time can be adjusted.

  As described above, the supply device 200 is immediately supplied with pressure from the first pressure accumulation tank T1 through the auxiliary pipe even when the pressure in the branch pipe branched from the main pipe TU0 decreases. Furthermore, even when the pressure in the first pressure accumulation tank T1 decreases, the pressure is immediately supplied from the second pressure accumulation tank T2 through the tank communication TU110. Thereby, even if it is a case where a pressure falls instantaneously and locally, the pressure more than the operation guarantee value of an air equipment can be maintained. That is, according to the supply device of the first embodiment, it is possible to cope with an instantaneous and local pressure drop.

  Moreover, providing a plurality of pressure storage chamber tanks is advantageous when the site where the supply device 200 is arranged is extensive. That is, if the pressure storage chamber tank and the air device are separated from each other, pressure loss occurs and the reaction speed also deteriorates.However, by providing multiple pressure storage chamber tanks and arranging them appropriately in the site, pressure loss is reduced. , Compressed air can be supplied efficiently.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications, within the scope of the gist of the present invention described in the claims, It can be changed.

  For example, in the above example, the first compressed air supply means and the second compressed air supply means are provided, but other compressed air supply means can also be provided.

DESCRIPTION OF SYMBOLS 10 Control part 20 Compressor ST1 1st tank pressure sensor ST2 2nd tank pressure sensor S1 1st pressure sensor S2 2nd pressure sensor S3 3rd pressure sensor T1 1st pressure accumulation tank T2 2nd pressure accumulation tank V1 1st control valve V11 1st Auxiliary valve V2 2nd control valve V21 2nd auxiliary valve V3 3rd control valve V31 3rd auxiliary valve VT1 1st tank control valve VT2 2nd tank control valve VTT1 Tank communication control valve 100, 200 Supply device TU0 Main piping TU1 1st Branch pipe TU11 first auxiliary pipe TU2 second branch pipe TU21 second auxiliary pipe TU3 third branch pipe TU31 third auxiliary pipe TU101 first tank connection pipe TU102 second tank connection pipe TU110 tank communication pipe TU120 short-circuit pipe M1 first air Equipment M2 Second air equipment M3 Third air equipment

Claims (8)

First compressed air supply means;
A main pipe through which air pumped by the first compressed air supply means flows;
A branch pipe branched from the main pipe and connected to a work machine that operates using the air;
An auxiliary pipe joining the branch pipe;
Second compressed air supply means for pumping air to the auxiliary pipe;
A pressure sensor for measuring the pressure of air flowing in the branch pipe;
Flow path switching means for changing the air flow state of the branch pipe and the auxiliary pipe;
A control unit that operates the flow path switching unit based on information acquired by the pressure sensor;
Compressed air supply device.   The compressed air supply device according to claim 1, wherein the main pipe includes a loop-shaped pipe.   The compressed air supply apparatus according to claim 2, wherein the loop-shaped pipe includes a short-circuit pipe.   The compressed air supply device according to any one of claims 1 to 3, wherein the second compressed air supply means is a first pressure accumulation tank to which compressed air is supplied from the first compressed air supply means.   The first pressure accumulation tank is connected to the main pipe via a first tank connection pipe, and the first tank connection pipe is a tank control valve that controls the inflow of air from the main pipe to the first pressure accumulation tank. The apparatus for supplying compressed air according to claim 4.   The compressed air supply device according to claim 4 or 5, wherein the second compressed air supply means includes a second pressure accumulation tank to which compressed air is supplied from the first compressed air supply means.   A tank communication control valve comprising a tank communication pipe connecting the first pressure accumulation tank and the second pressure accumulation tank, and controlling a flow state of air between the first pressure accumulation tank and the second pressure accumulation tank in the tank communication pipe. The apparatus for supplying compressed air according to claim 6.   The compressed air according to any one of claims 1 to 7, wherein the flow path switching means includes a control valve that controls the flow of air in the branch pipe and an auxiliary valve that controls the flow of air in the auxiliary pipe. Feeding device.

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