Dry air supply device

Abstract

To improve the durability of a pneumatic device by appropriately adjusting the dew-point temperature of dry air supplied to the pneumatic device.SOLUTION: A first flow rate control valve 20 adjusts a flow rate of dry air flowing through a main flow path 51 so that the flow rate of the dry air detected by a first flow meter 21 can become a flow rate where the dew-point temperature of the dry air does not exceed a preset dew-point temperature. A dry air supply device 10 adjusts the opening of a second flow rate control valve 28 so that an air flow rate detected by a second flow meter 29 can be a flow rate calculated on the basis of a saturation water vapor content of the dry air derived from a dew-point temperature detected by a first dew point meter 22, a saturation water vapor content of air derived from a dew-point temperature detected by a second dew point meter 30, a saturation water vapor content derived from the preset dew-point temperature, and the flow rate of the dry air detected by the first flow meter 21, and adjusts a dew-point temperature of the dry air flowing through a merging flow path 53 to the preset dew-point temperature.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a dry air supply device. [Background technology]

[0002] In a dry air supplying device, in order to supply air supplied from an air supply source as dry air to a pneumatic device, it is necessary to remove moisture contained in the air supplied from the air supply source to make the air dry. Therefore, as in Patent Document 1, for example, the moisture contained in the air supplied from the air supply source is removed by a dehumidification unit. Therefore, the dry air supplying device is provided with a supply line having a dehumidification unit. Then, the dry air supplying device supplies the dry air from which moisture has been removed by the dehumidification unit to the pneumatic device via the supply line. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-87619 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a dry air supplying device, the dew point temperature of the dry air supplied to the pneumatic equipment varies with the variation in the flow rate of dry air consumed by the pneumatic equipment. For example, as the flow rate of dry air consumed by the pneumatic equipment increases, the dew point temperature of the dry air supplied to the pneumatic equipment increases. Here, in the dry air supplying device, the dew point temperature of the dry air supplied to the pneumatic equipment is adjusted so that it does not exceed a preset dew point temperature. Specifically, for example, the flow rate of the dry air flowing through the supply line is adjusted so that the flow rate of the dry air flowing through the supply line is such that the dew point temperature of the dry air does not exceed the set dew point temperature. In this way, it is possible to prevent dry air that exceeds the set dew point temperature from being supplied to the pneumatic equipment through the supply line.

[0005] On the other hand, as the flow rate of dry air consumed by the pneumatic equipment decreases, the dew point temperature of the dry air supplied to the pneumatic equipment decreases. In this case, in the conventional dry air supplying device, it is not possible to adjust the dew point temperature of the dry air supplied to the pneumatic equipment in accordance with the decrease in the flow rate of dry air consumed by the pneumatic equipment. If dry air with an excessively low dew point temperature is supplied to the pneumatic equipment, there is a risk that the lubricant used in the pneumatic equipment will dry out due to exposure to the dry air. If the lubricant in the pneumatic equipment dries out, there is a risk that the durability of the pneumatic equipment will deteriorate. Therefore, it is desired to improve the durability of the pneumatic equipment by appropriately adjusting the dew point temperature of the dry air supplied to the pneumatic equipment. [Means for solving the problem]

[0006] Various aspects for solving the above problems will be described below. [Aspect 1] A supply line having a dehumidifying unit for removing moisture contained in air supplied from an air supply source is provided, A dry air supply device that supplies dry air from which moisture has been removed by the dehumidification unit to a pneumatic device via the supply line, The supply line is A main flow path having the dehumidification unit; a branch flow path that branches off from a portion of the main flow path that is located closer to the air supply source than the dehumidifier, bypasses the dehumidifier, and merges with a portion of the main flow path that is closer to the pneumatic device than the dehumidifier; a junction flow path having a first end connected to a junction between the main flow path and the branch flow path and a second end connected to the pneumatic device, a first flow meter that detects a flow rate of dry air that has had moisture removed by the dehumidifier and flows through the main flow path; a first flow control valve that adjusts the flow rate of the dry air flowing through the main flow path so that the flow rate of the dry air detected by the first flow meter is a flow rate that does not cause the dew point temperature of the dry air to exceed a preset dew point temperature; a first dew point meter for detecting a dew point temperature of the dry air flowing through the main flow path; a second flow control valve that adjusts the flow rate of air flowing through the branch flow path; a second flow meter for detecting a flow rate of air flowing through the branch flow path; a second dew point meter for detecting a dew point temperature of the air flowing through the branch flow path, a dew point temperature of the dry air flowing through the junction flow path is adjusted to the set dew point temperature by adjusting an aperture of the second flow control valve so that the flow rate of the air detected by the second flow meter becomes a flow rate calculated based on the amount of saturated water vapor of the dry air derived from the dew point temperature detected by the first dew point meter, the amount of saturated water vapor of the air derived from the dew point temperature detected by the second dew point meter, the amount of saturated water vapor derived from the set dew point temperature, and the flow rate of the dry air detected by the first flow meter.

[0007] [Aspect 2] a first check valve is provided in the main flow path to prevent backflow of dry air from the junction flow path to the main flow path, The dry air supplying device according to [Aspect 1], wherein the branch flow path is provided with a second check valve for preventing backflow of dry air from the junction flow path to the branch flow path.

[0008] [Aspect 3] The dry air supplying device according to [Aspect 1] or [Aspect 2], further comprising a control unit that automatically controls an aperture of the second flow control valve so that the flow rate of air detected by the second flow meter becomes a flow rate calculated based on the amount of saturated water vapor of the dry air derived from the dew point temperature detected by the first dew point meter, the amount of saturated water vapor of the air derived from the dew point temperature detected by the second dew point meter, the amount of saturated water vapor derived from the set dew point temperature, and the flow rate of dry air detected by the first flow meter.

[0009] [Aspect 4] The dry air supplying device according to any one of [Aspect 1] to [Aspect 3], further comprising a flow path unit in which the main flow path and the branch flow paths are integrated together. Effect of the Invention

[0010] According to the present invention, the durability of pneumatic equipment can be improved by appropriately adjusting the dew point temperature of the dry air supplied to the pneumatic equipment. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a circuit diagram for explaining a dry air supplying device according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, one embodiment of a dry air supplying device will be described with reference to FIG. <Outline of the dry air supply device> As shown in Fig. 1, the dry air supplying device 10 includes a first main line filter 11, a dryer 12, a second main line filter 13, and a first tank 14. The dry air supplying device 10 includes a first filter 15, a first oil mist filter 16, a first pressure reducing valve 17, and a first pressure gauge 18. The dry air supplying device 10 includes a dehumidifying section 19, a first flow control valve 20, a first flow meter 21, a first dew point meter 22, and a first check valve 23. The dry air supplying device 10 includes a second filter 24, a second oil mist filter 25, a second pressure reducing valve 26, a second pressure gauge 27, a second flow control valve 28, a second flow meter 29, a second dew point meter 30, and a second check valve 31. The dry air supplying device 10 includes a second tank 32, a third pressure gauge 33, a third dew point meter 34, and a third check valve 35. The dry air supplying device 10 includes a flow path unit 36. The flow path unit 36 ​​includes a housing 37. The housing 37 has a supply port 38 and a discharge port 39.

[0013] The dry air supplying device 10 includes a supply pipe 40. A first end of the supply pipe 40 is connected to an air supply source A1. The air supply source A1 is a compressor that compresses and discharges air. A second end of the supply pipe 40 is connected to a supply port 38 of a housing 37.

[0014] The supply pipe 40 is provided with a first main line filter 11, a dryer 12, a second main line filter 13, and a first tank 14. The first main line filter 11, the dryer 12, the second main line filter 13, and the first tank 14 are arranged in this order on the supply pipe 40 from the air supply source A1 toward the supply port 38 of the housing 37. The air discharged from the air supply source A1 to the supply pipe 40 flows through the first main line filter 11, the dryer 12, the second main line filter 13, and the first tank 14 in this order.

[0015] The first main line filter 11 is configured to be capable of removing impurities such as oil, water, and foreign matter contained in the air discharged from the air supply source A1 to the supply piping 40. The dryer 12 is configured to be capable of removing moisture contained in the air that has passed through the first main line filter 11. The second main line filter 13 is configured to be capable of removing impurities such as oil, water, and foreign matter contained in the air from which moisture has been removed by the dryer 12. The first tank 14 is configured to be capable of temporarily storing the air that has passed through the second main line filter 13. The air stored in the first tank 14 is supplied to the supply port 38 of the housing 37 via the supply piping 40.

[0016] The housing 37 has a first flow path 41. A first end of the first flow path 41 is connected to the supply port 38. A second end of the first flow path 41 is connected to the exhaust port 39. The first filter 15, the first oil mist filter 16, the first pressure reducing valve 17, the first pressure gauge 18, the dehumidification unit 19, the first flow control valve 20, the first flow meter 21, the first dew point meter 22, and the first check valve 23 are provided in the first flow path 41. The first filter 15, the first oil mist filter 16, the first pressure reducing valve 17, the first pressure gauge 18, the dehumidification unit 19, the first flow control valve 20, the first flow meter 21, the first dew point meter 22, and the first check valve 23 are arranged in this order in the first flow path 41 from the supply port 38 toward the exhaust port 39. The air flowing from the supply port 38 to the first flow path 41 flows in the following order: the first filter 15, the first oil mist filter 16, the first pressure reducing valve 17, the first pressure gauge 18, the dehumidification section 19, the first flow control valve 20, the first flow meter 21, the first dew point meter 22, and the first check valve 23.

[0017] The first filter 15 is configured to be capable of removing dust and water droplets contained in the air passing through the first filter 15. The first oil mist filter 16 is configured to be capable of removing oil particles contained in the air passing through the first oil mist filter 16. The first pressure reducing valve 17 is configured to be capable of reducing the pressure of the air passing through the first pressure reducing valve 17 so that the pressure downstream of the first pressure reducing valve 17 in the first flow path 41 becomes a predetermined constant pressure. The first pressure gauge 18 is configured to be capable of detecting the pressure of the air passing through the first pressure reducing valve 17.

[0018] The dehumidifying section 19 is configured to be capable of removing moisture contained in the air. Therefore, the dehumidifying section 19 removes moisture contained in the air supplied from the air supply source A1. Specifically, the dehumidifying section 19 is a heatless dryer that adsorbs moisture contained in the air with a moisture absorbent material to dehumidify the air. The heatless dryer is configured to repeatedly perform a dehumidification process in which the moisture contained in the air is adsorbed by the moisture absorbent material, and a regeneration process in which the moisture absorbent material is regenerated.

[0019] The first flow control valve 20 is configured to be capable of adjusting the flow rate of the dry air from which moisture has been removed in the dehumidifying section 19. The first flow meter 21 is configured to be capable of detecting the flow rate of the dry air passing through the first flow control valve 20. The first dew point meter 22 is configured to be capable of detecting the dew point temperature of the dry air from which moisture has been removed in the dehumidifying section 19. The first check valve 23 is configured to allow the flow of dry air from the upstream side of the first check valve 23 to the downstream side in the first flow path 41, and to block the flow of dry air from the downstream side of the first check valve 23 to the upstream side in the first flow path 41.

[0020] The housing 37 has a second flow path 42. A first end of the second flow path 42 is connected to a portion of the first flow path 41 between the supply port 38 and the first filter 15. Therefore, the second flow path 42 branches off from the first flow path 41. A part of the air flowing from the supply port 38 through the first flow path 41 branches off from the first flow path 41 to flow into the second flow path 42. A second end of the second flow path 42 is connected to a portion of the first flow path 41 between the first check valve 23 and the discharge port 39. Therefore, the second flow path 42 merges with the first flow path 41.

[0021] The second flow path 42 is provided with the second filter 24, the second oil mist filter 25, the second pressure reducing valve 26, the second pressure gauge 27, the second flow control valve 28, the second flow meter 29, the second dew point meter 30, and the second check valve 31. The second filter 24, the second oil mist filter 25, the second pressure reducing valve 26, the second pressure gauge 27, the second flow control valve 28, the second flow meter 29, the second dew point meter 30, and the second check valve 31 are arranged in this order from the first end to the second end of the second flow path 42. Air from the first end of the second flow path 42 flows through the second filter 24, the second oil mist filter 25, the second pressure reducing valve 26, the second pressure gauge 27, the second flow control valve 28, the second flow meter 29, the second dew point meter 30, and the second check valve 31 in this order.

[0022] The second filter 24 is configured to be capable of removing dust and water droplets contained in the air passing through the second filter 24. The second oil mist filter 25 is configured to be capable of removing oil particles contained in the air passing through the second oil mist filter 25. The second pressure reducing valve 26 is configured to be capable of reducing the pressure of the air passing through the second pressure reducing valve 26 so that the pressure downstream of the second pressure reducing valve 26 in the second flow path 42 becomes a predetermined constant pressure. The second pressure gauge 27 is configured to be capable of detecting the pressure of the air passing through the second pressure reducing valve 26.

[0023] The second flow control valve 28 is configured to be capable of adjusting the flow rate of air flowing through the second flow path 42. The second flow meter 29 is configured to be capable of detecting the flow rate of air flowing through the second flow path 42. The second dew point meter 30 is configured to be capable of detecting the dew point temperature of air flowing through the second flow path 42. The second check valve 31 is configured to allow air to flow from the upstream side of the second check valve 31 to the downstream side in the second flow path 42, and to block air from the downstream side of the second check valve 31 to the upstream side in the second flow path 42.

[0024] The dry air supplying device 10 includes an exhaust pipe 43. A first end of the exhaust pipe 43 is connected to the exhaust port 39. A second end of the exhaust pipe 43 is connected to a pneumatic device A2. The pneumatic device A2 is composed of an air pressure valve A3 and an air pressure cylinder A4.

[0025] The discharge pipe 43 is provided with the second tank 32, the third pressure gauge 33, the third dew point gauge 34, and the third check valve 35. The second tank 32, the third pressure gauge 33, the third dew point gauge 34, and the third check valve 35 are arranged in this order from the first end to the second end of the discharge pipe 43. The dry air discharged from the discharge port 39 and flowing through the discharge pipe 43 flows through the second tank 32, the third pressure gauge 33, the third dew point gauge 34, and the third check valve 35 in this order.

[0026] The second tank 32 is configured to be able to temporarily store the dry air discharged from the discharge port 39 into the discharge pipe 43. The third pressure gauge 33 is configured to be able to detect the pressure of the dry air flowing through the discharge pipe 43. The third dew point meter 34 is configured to be able to detect the dew point temperature of the dry air flowing through the discharge pipe 43. The third check valve 35 is configured to allow the flow of dry air from the upstream side of the third check valve 35 to the downstream side in the discharge pipe 43, and to block the flow of dry air from the downstream side of the third check valve 35 to the upstream side in the discharge pipe 43.

[0027] <Supply line> The supply pipe 40, the supply port 38, the first flow path 41, the second flow path 42, the exhaust port 39, and the exhaust pipe 43 configure a supply line 50. Thus, the dry air supplying device 10 includes the supply line 50 having the dehumidifying section 19. The dry air supplying device 10 supplies dry air, from which moisture has been removed by the dehumidifying section 19, to the pneumatic device A2 via the supply line 50.

[0028] In the first flow path 41, a portion from a first end of the first flow path 41 to a junction with the second flow path 42 constitutes a main flow path 51 having a dehumidifier 19. Thus, the supply line 50 has the main flow path 51 having the dehumidifier 19. Then, the second flow path 42 constitutes a branch flow path 52 that branches off from a portion of the main flow path 51 that is closer to the air supply source A1 than the dehumidifier 19, bypasses the dehumidifier 19, and joins a portion of the main flow path 51 that is closer to the pneumatic device A2 than the dehumidifier 19. Thus, the supply line 50 has a branch flow path 52.

[0029] The main flow path 51 and the branch flow paths 52 are integrated by the flow path unit 36. Therefore, the dry air supplying device 10 includes the flow path unit 36 ​​in which the main flow path 51 and the branch flow paths 52 are integrated.

[0030] The portion of the first flow path 41 from the junction with the second flow path 42 to the discharge port 39, the discharge port 39, and the discharge piping 43 constitute a junction flow path 53 having a first end connected to the junction of the main flow path 51 and the branch flow path 52 and a second end connected to the pneumatic device A2. Thus, the supply line 50 has the junction flow path 53.

[0031] The first flow meter 21 detects the flow rate of the dry air flowing through the main flow path 51 after moisture has been removed by the dehumidifier 19. The first flow control valve 20 adjusts the flow rate of the dry air flowing through the main flow path 51. The first dew point meter 22 detects the dew point temperature of the dry air flowing through the main flow path 51. The second flow control valve 28 adjusts the flow rate of the air flowing through the branch flow path 52. The second flow meter 29 detects the flow rate of the air flowing through the branch flow path 52. The second dew point meter 30 detects the dew point temperature of the air flowing through the branch flow path 52.

[0032] The first check valve 23 prevents the backflow of dry air from the junction flow path 53 to the main flow path 51. Therefore, the main flow path 51 is provided with the first check valve 23 for preventing the backflow of dry air from the junction flow path 53 to the main flow path 51. The second check valve 31 prevents the backflow of dry air from the junction flow path 53 to the branch flow path 52. Therefore, the branch flow path 52 is provided with the second check valve 31 for preventing the backflow of dry air from the junction flow path 53 to the branch flow path 52.

[0033] <Control Unit> The dry air supplying device 10 includes a control unit 60. The control unit 60 includes a central processing unit (CPU). The control unit 60 also includes a memory including a read-only memory (ROM) in which various programs and maps are stored in advance, and a random access memory (RAM) for temporarily storing the results of CPU calculations, etc. The control unit 60 also includes a timer counter, an input interface, an output interface, etc.

[0034] Here, the dew point temperature of the dry air supplied from the dry air supplying device 10 to the pneumatic device A2 via the supply line 50 is preset according to the pneumatic device A2. The control unit 60 pre-stores the dew point temperature that is preset according to the pneumatic device A2 as a "set dew point temperature." The control unit 60 also pre-stores a map that correlates the dew point temperature with the saturated water vapor amount of the dry air. The control unit 60 is then able to derive the saturated water vapor amount of the dry air from the set dew point temperature using the map.

[0035] The control unit 60 is electrically connected to the first pressure reducing valve 17. The control unit 60 controls the operation of the first pressure reducing valve 17. The control unit 60 is electrically connected to the first pressure gauge 18. The control unit 60 receives information related to the air pressure detected by the first pressure gauge 18. The control unit 60 pre-stores a program for controlling the operation of the first pressure reducing valve 17 so that the air pressure detected by the first pressure gauge 18 becomes a predetermined constant pressure.

[0036] The control unit 60 is electrically connected to the dehumidifier 19. The control unit 60 controls the driving of the dehumidifier 19. Specifically, the control unit 60 controls the driving of the dehumidifier 19 so that the dehumidifier 19 repeats a dehumidification process and a regeneration process.

[0037] The control unit 60 is electrically connected to the first flow control valve 20. The control unit 60 controls the operation of the first flow control valve 20. The control unit 60 is electrically connected to the first flow meter 21. The control unit 60 receives information on the flow rate of dry air detected by the first flow meter 21. The control unit 60 prestores a program for controlling the operation of the first flow control valve 20 so that the flow rate of dry air detected by the first flow meter 21 is a flow rate at which the dew point temperature of the dry air does not exceed a preset dew point temperature. Therefore, the first flow control valve 20 adjusts the flow rate of dry air flowing through the main flow path 51 so that the flow rate of dry air detected by the first flow meter 21 is a flow rate at which the dew point temperature of the dry air does not exceed a preset dew point temperature.

[0038] The control unit 60 is electrically connected to the first dew point meter 22. The control unit 60 receives information related to the dew point temperature of the dry air detected by the first dew point meter 22. The control unit 60 stores in advance a map in which the dew point temperature of the dry air detected by the first dew point meter 22 and the amount of saturated water vapor in the dry air are associated with each other. The control unit 60 is then able to derive the amount of saturated water vapor in the dry air from the dew point temperature of the dry air detected by the first dew point meter 22 using the map.

[0039] The control unit 60 is electrically connected to the second pressure reducing valve 26. The control unit 60 controls the operation of the second pressure reducing valve 26. The control unit 60 is electrically connected to the second pressure gauge 27. The control unit 60 receives information related to the air pressure detected by the second pressure gauge 27. The control unit 60 pre-stores a program for controlling the operation of the second pressure reducing valve 26 so that the air pressure detected by the second pressure gauge 27 becomes a predetermined constant pressure.

[0040] The control unit 60 is electrically connected to the second flow control valve 28. The control unit 60 controls the operation of the second flow control valve 28. The control unit 60 is electrically connected to the second flow meter 29. The control unit 60 receives information related to the air flow rate detected by the second flow meter 29. The control unit 60 is electrically connected to the second dew point meter 30. The control unit 60 receives information related to the air dew point temperature detected by the second dew point meter 30. The control unit 60 stores in advance a map in which the air dew point temperature detected by the second dew point meter 30 is associated with the amount of saturated water vapor in the air. The control unit 60 is then able to derive the amount of saturated water vapor in the air from the air dew point temperature detected by the second dew point meter 30 using the map.

[0041] The control unit 60 is electrically connected to the third pressure gauge 33. The control unit 60 receives information related to the pressure of the dry air detected by the third pressure gauge 33. The control unit 60 is electrically connected to the third dew point meter 34. The control unit 60 receives information related to the dew point temperature of the dry air detected by the third dew point meter 34.

[0042] Here, the saturated water vapor amount of the dry air derived from the dew point temperature of the dry air detected by the first dew point meter 22 is defined as "a1". The saturated water vapor amount of the air derived from the dew point temperature of the air detected by the second dew point meter 30 is defined as "a2". The saturated water vapor amount of the dry air derived from the set dew point temperature is defined as "ax". The flow rate of the dry air detected by the first flow meter 21 is defined as "R1". In this case, if the flow rate of the air flowing through the branch flow path 52 is defined as "R2", the following formula (1) is established.

[0043]

number

[0044] The control unit 60 automatically controls the opening degree of the second flow control valve 28 so that the air flow rate detected by the second flow meter 29 becomes a flow rate calculated based on the amount of saturated water vapor in the dry air derived from the dew point temperature detected by the first dew point meter 22, the amount of saturated water vapor in the air derived from the dew point temperature detected by the second dew point meter 30, the amount of saturated water vapor derived from the set dew point temperature, and the dry air flow rate detected by the first flow meter 21.

[0045] [Operation of the embodiment] Next, the operation of this embodiment will be described. The air from the air supply source A1 becomes dry air by removing moisture in the dehumidifier 19. The dry air from which moisture has been removed in the dehumidifier 19 is then supplied to the pneumatic device A2 via the supply line 50.

[0046] The first flow control valve 20 adjusts the flow rate of the dry air flowing through the main flow path 51 so that the flow rate of the dry air detected by the first flow meter 21 is a flow rate at which the dew point temperature of the dry air does not exceed a preset dew point temperature. This prevents the dry air, whose temperature exceeds the preset dew point temperature, from being supplied to the pneumatic device A2 through the supply line 50. The control unit 60 adjusts the opening of the second flow control valve 28 so that the flow rate of the air detected by the second flow meter 29 is a flow rate calculated from the formula (1). Then, the air that bypasses the dehumidifier 19 and flows through the branch flow path 52 merges with the main flow path 51 by the amount of the air flow rate adjusted by the second flow control valve 28. The merged flow path 53 is filled with dry air at a flow rate that is the sum of the flow rate of the dry air flowing through the main flow path 51 and the flow rate of the air flowing through the branch flow path 52. In this way, the dew point temperature of the dry air flowing through the merged flow path 53 is adjusted to the set dew point temperature.

[0047] [Effects of the embodiment] The above embodiment can provide the following effects. (1) The first flow control valve 20 adjusts the flow rate of dry air flowing through the main flow path 51 so that the flow rate of dry air detected by the first flow meter 21 is a flow rate at which the dew point temperature of the dry air does not exceed a preset set dew point temperature. This prevents dry air whose temperature exceeds the set dew point temperature from being supplied to the pneumatic device A2 through the supply line 50. In the dry air supplying device 10, the opening of the second flow control valve 28 is adjusted so that the flow rate of air detected by the second flow meter 29 is a flow rate calculated based on the saturated water vapor amount of the dry air derived from the dew point temperature detected by the first dew point meter 22, the saturated water vapor amount of the air derived from the dew point temperature detected by the second dew point meter 30, the saturated water vapor amount derived from the set dew point temperature, and the flow rate of dry air detected by the first flow meter 21, thereby adjusting the dew point temperature of the dry air flowing through the junction flow path 53 to the set dew point temperature. This makes it possible to avoid a problem in that dry air with an excessively low dew point temperature is supplied to the pneumatic device A2 even if the flow rate of dry air consumed by the pneumatic device A2 is reduced. Therefore, it is possible to prevent the lubricant used in the pneumatic device A2 from drying out due to exposure to dry air. As a result, it is possible to improve the durability of the pneumatic device A2. In this way, by appropriately adjusting the dew point temperature of the dry air supplied to the pneumatic device A2, it is possible to improve the durability of the pneumatic device A2.

[0048] (2) The main flow path 51 is provided with a first check valve 23 for preventing backflow of dry air from the junction flow path 53 to the main flow path 51. The branch flow path 52 is provided with a second check valve 31 for preventing backflow of dry air from the junction flow path 53 to the branch flow path 52. This makes it possible to more appropriately adjust the dew point temperature of the dry air supplied to the pneumatic device A2.

[0049] (3) The dry air supplying device 10 is provided with a control unit 60 that automatically controls the aperture of the second flow control valve 28 so that the flow rate of air detected by the second flow meter 29 becomes a flow rate calculated based on the amount of saturated water vapor in the dry air derived from the dew point temperature detected by the first dew point meter 22, the amount of saturated water vapor in the air derived from the dew point temperature detected by the second dew point meter 30, the amount of saturated water vapor derived from the set dew point temperature, and the flow rate of dry air detected by the first flow meter 21. This eliminates the need for an operator to manually adjust the aperture of the second flow control valve 28, making it possible to easily adjust the dew point temperature of the dry air supplied to the pneumatic device A2.

[0050] (4) The dry air supplying device 10 includes the flow passage unit 36 ​​in which the main flow passage 51 and the branch flow passage 52 are integrated together. This allows the dry air supplying device 10 to have a compact configuration.

[0051] [Example of change] The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0052] In the embodiment, the opening degree of the second flow control valve 28 may be adjusted manually. In the embodiment, the dry air supplying device 10 does not need to include the passage unit 36, and the main passage 51 and the branch passages 52 may not be integrated. [Explanation of symbols]

[0053] 10...dry air supply device, 19...dehumidification section, 20...first flow control valve, 21...first flow meter, 22...first dew point meter, 23...first check valve, 28...second flow control valve, 29...second flow meter, 30...second dew point meter, 31...second check valve, 36...flow path unit, 50...supply line, 51...main flow path, 52...branch flow path, 53...junction flow path, 60...control section, A1...air supply source, A2...pneumatic equipment.

Claims

1. A supply line having a dehumidifying unit for removing moisture contained in air supplied from an air supply source is provided, A dry air supply device that supplies dry air from which moisture has been removed by the dehumidification unit to a pneumatic device via the supply line, The supply line is A main flow path having the dehumidification unit; a branch flow path that branches off from a portion of the main flow path that is located closer to the air supply source than the dehumidifier, bypasses the dehumidifier, and merges with a portion of the main flow path that is closer to the pneumatic device than the dehumidifier; a junction flow path having a first end connected to a junction of the main flow path and the branch flow path and a second end connected to the pneumatic device, a first flow meter that detects a flow rate of dry air that has had moisture removed by the dehumidifier and flows through the main flow path; a first flow control valve that adjusts the flow rate of the dry air flowing through the main flow path so that the flow rate of the dry air detected by the first flow meter is a flow rate that does not cause the dew point temperature of the dry air to exceed a preset dew point temperature; a first dew point meter for detecting a dew point temperature of the dry air flowing through the main flow path; a second flow control valve that adjusts the flow rate of air flowing through the branch flow path; a second flow meter for detecting a flow rate of air flowing through the branch flow path; a second dew point meter that detects a dew point temperature of the air flowing through the branch flow path, a dew point temperature of the dry air flowing through the junction flow path being adjusted to the set dew point temperature by adjusting an opening of the second flow control valve so that the flow rate of the air detected by the second flow meter becomes a flow rate calculated based on the amount of saturated water vapor of the dry air derived from the dew point temperature detected by the first dew point meter, the amount of saturated water vapor of the air derived from the dew point temperature detected by the second dew point meter, the amount of saturated water vapor derived from the set dew point temperature, and the flow rate of the dry air detected by the first flow meter.

2. a first check valve is provided in the main flow path to prevent backflow of dry air from the junction flow path to the main flow path, 2. The dry air supply device according to claim 1, wherein the branch passage is provided with a second check valve for preventing a backflow of dry air from the junction passage to the branch passage.

3. 3. The dry air supply device according to claim 1 or 2, further comprising a control unit that automatically controls an opening degree of the second flow control valve so that the flow rate of the air detected by the second flow meter becomes a flow rate calculated based on the amount of saturated water vapor of the dry air derived from the dew-point temperature detected by the first dew point meter, the amount of saturated water vapor of the air derived from the dew-point temperature detected by the second dew point meter, the amount of saturated water vapor derived from the set dew-point temperature, and the flow rate of the dry air detected by the first flow meter.

4. 2. The dry air supplying device according to claim 1, further comprising a flow path unit in which the main flow path and the branch flow paths are integrated together.

Images