Pulse air generator

Abstract

To accurately adjust the frequency in a pulsed air generator. [Solution] The third communication passage is provided with a first control valve 81 that adjusts the flow rate of air discharged to the outside from the second pilot chamber 59 via the discharge port 26, and the discharge passage 77 is provided with a second control valve 95 that adjusts the flow rate of air discharged to the outside from the main valve pilot chamber 32 via the first output port 48 and the first discharge port 50. Since the first control valve 81 and the second control valve 95 do not adjust the flow rate of air supplied to the pilot chamber as in the prior art, the pressure inside the pilot chamber does not gradually increase from atmospheric pressure. Therefore, problems such as unstable operation of the pilot valve section 12 are avoided.

Description

Technical Field

[0001] The present invention relates to a pulse air generator.

Background Art

[0002] Conventionally, a pulse air generator that intermittently discharges air to the outside from a discharge port is known. The pulse air generator includes a main valve section and a pilot valve section. The main valve section has a suction port, a discharge port, a main valve pilot chamber, a main valve chamber, and a main valve body. The main valve body is housed in the main valve chamber. Then, the main valve section intermittently discharges the air sucked from the suction port to the outside from the discharge port by switching the main valve body. The pilot valve section moves the main valve body by supplying and discharging pilot air to and from the main valve pilot chamber.

[0003] In such a pulse air device, for example, as in Patent Document 1, there may be two variable throttle valves for adjusting the air flow rate. One variable throttle valve adjusts the air flow rate supplied to the pilot chamber of the pilot valve section. Thereby, adjustment of the cutoff time during which the discharge of air from the discharge port is blocked is performed. The other variable throttle valve adjusts the air flow rate discharged from the main valve pilot chamber of the main valve section. Thereby, adjustment of the discharge time during which air is discharged from the discharge port is performed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, as in Patent Document 1, when the flow rate of air supplied to the pilot chamber of the pilot valve is adjusted by one of the variable throttles, the pressure inside the pilot chamber is gradually increased from atmospheric pressure, which makes the operation of the pilot valve unstable. Therefore, there is a risk that the length of the cycle, which is the time from when air is discharged from the discharge port until the discharge of air from the discharge port is interrupted and then discharged again, cannot be adjusted with precision. As a result, there is a risk that the frequency cannot be adjusted with precision in the pulse air generator. [Means for solving the problem]

[0006] The following describes various methods for solving the above problems. [Aspect 1] A main valve unit having an intake port, a discharge port, a main valve pilot chamber, a main valve chamber, and a main valve body housed in the main valve chamber, which intermittently discharges air drawn in from the intake port to the outside through the discharge port when the main valve body is switched, A pulse air generator comprising a pilot valve section that moves the main valve body by supplying and discharging pilot air to the main valve pilot chamber, The pilot valve section is The body and A valve hole formed in the body, The body is formed and communicates with the valve holes, respectively, a supply port, a first output port, a second output port, a first discharge port, and a second discharge port, A first valve body and a second valve body are housed in the valve hole so as to be reciprocable, A first pilot chamber through which pilot air is supplied and discharged to move the first valve body, It has a second pilot chamber through which pilot air is supplied and discharged to move the second valve body, The first valve body switches to a first position where, when air is discharged from the first pilot chamber, it blocks the airflow between the supply port and the first output port and allows the airflow between the first output port and the first discharge port; and when air is supplied to the first pilot chamber, it switches to a second position where it allows the airflow between the supply port and the first output port and blocks the airflow between the first output port and the first discharge port. The second valve body switches to a third position when the first valve body switches to the first position, which allows airflow between the supply port and the second output port and blocks airflow between the second output port and the second discharge port, and switches to a fourth position when the first valve body switches to the second position, which blocks airflow between the supply port and the second output port and allows airflow between the second output port and the second discharge port. A supply channel connecting the intake port and the supply port, A first communication channel connecting the first output port and the main valve pilot chamber, A second communication channel connecting the second output port and the first pilot chamber, A third communication channel connecting the discharge port and the second pilot chamber, The device comprises a discharge channel that connects the first discharge port to the outside, The third communication channel is provided with a first control valve that adjusts the flow rate of air discharged from the second pilot chamber to the outside via the discharge port. A pulse air generator characterized in that the discharge channel is provided with a second control valve for adjusting the flow rate of air discharged to the outside from the main valve pilot chamber through the first output port and the first discharge port.

[0007] [Aspect 2] The main valve section has a first valve seat and a second valve seat which are arranged opposite to each other in the direction of movement of the main valve body within the main valve chamber. The pulse air generator according to [Aspect 1], characterized in that the main valve body is a poppet valve that, by seating on the first valve seat, allows communication between the intake port and the discharge port via the main valve chamber, and by seating on the second valve seat, blocks communication between the intake port and the discharge port via the main valve chamber.

[0008] [Aspect 3] The pulse air generator according to [Aspect 1] or [Aspect 2], characterized in that the first valve body and the second valve body are spool valves arranged adjacent to each other in the axial direction of the valve hole.

[0009] [Aspect 4] A pulse air generator according to any one of [Aspect 1] to [Aspect 3], characterized by comprising a maintenance unit that maintains a state in which the first valve body is switched to the second position and the second valve body is switched to the fourth position.

[0010] [Aspect 5] The pulse air generator according to [Aspect 4], characterized in that the maintenance unit is provided downstream of the second control valve in the discharge passage and is an on / off valve for opening and closing the discharge passage. [Effects of the Invention]

[0011] According to this invention, the frequency of a pulsed air generator can be adjusted with high precision. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a cross-sectional view showing a pulsed air generator in an embodiment. [Figure 2] Figure 2 is a cross-sectional view showing a pulsed air generator. [Figure 3] Figure 3 is a cross-sectional view showing a pulsed air generator. [Figure 4] Figure 4 is a cross-sectional view showing a pulsed air generator. [Figure 5]FIG. 5 is a cross-sectional view showing a pulse air generator. [Figure 6] FIG. 6 is a cross-sectional view showing a pulse air generator. [Figure 7] FIG. 7 is a cross-sectional view showing a pulse air generator.

MODE FOR CARRYING OUT THE INVENTION

[0013] Hereinafter, an embodiment in which the pulse air generator is embodied will be described with reference to FIGS. 1 to 7. <Pulse Air Generator> As shown in FIG. 1, the pulse air generator 10 includes a main valve portion 11 and a pilot valve portion 12.

[0014] <Main Valve Portion> The main valve portion 11 has a main body 13. The main body 13 has a main body main body 14, a first connection block 15, and a second connection block 16. The main body main body 14 is cylindrical. A cylindrical portion 17 projects from a first end face of the main body main body 14 located on one axial direction of the main body main body 14.

[0015] The first connection block 15 is connected to the first end face of the main body main body 14. The first connection block 15 has a first recess 18. The first recess 18 is formed on an end face of the first connection block 15 on the side of the main body main body 14. The first recess 18 is circular. The first connection block 15 is connected to the first end face of the main body main body 14 with the cylindrical portion 17 of the main body main body 14 inserted inside the first recess 18. The axis of the first recess 18 coincides with the axis of the cylindrical portion 17.

[0016] The second connecting block 16 is connected to the second end face of the main body 14, which is located on the other side of the main body 14 in the axial direction. The second connecting block 16 has a second recess 19. The second recess 19 is formed on the end face of the second connecting block 16 that is on the main body 14 side. The second recess 19 is circular. The second connecting block 16 is connected to the second end face of the main body 14 with the axis of the second recess 19 coinciding with the axis of the first recess 18.

[0017] The main body 14 has a first hole 20, a main valve chamber 21, and a second hole 22. Therefore, the main valve section 11 has a main valve chamber 21. The first hole 20 is circular. The second hole 22 is circular. The axes of the first hole 20 and the second hole 22 coincide with the axis of the main body 14. The first end of the first hole 20 communicates with the inside of the cylindrical section 17. The second end of the first hole 20 communicates with the main valve chamber 21. The first end of the second hole 22 communicates with the main valve chamber 21. The second end of the second hole 22 opens to the second end face of the main body 14. The second end of the second hole 22 communicates with the second recess 19. The axes of the first hole 20 and the second hole 22 coincide with each other.

[0018] The main valve section 11 has an intake port 23. The intake port 23 is formed in the main body 14. The first end of the intake port 23 opens to the outer surface of the main body 14. The first end of the intake port 23 is connected to the air supply source 25 via piping 24. The second end of the intake port 23 communicates with the first hole 20. The main valve section 11 also has a discharge port 26. The discharge port 26 is formed in the main body 14. The first end of the discharge port 26 communicates with the main valve chamber 21. The second end of the discharge port 26 opens to the outer surface of the main body 14.

[0019] The main valve section 11 has a plug 27. The plug 27 is cylindrical. The plug 27 is inserted into the inside of the second hole 22 from the second end of the second hole 22. The inside of the plug 27 is in communication with the main valve chamber 21. A portion of the plug 27 protrudes from the second hole 22 toward the second end face of the main body 14 and is inserted into the inside of the second recess 19.

[0020] The main valve section 11 has a valve stem 28. The valve stem 28 is cylindrical. The valve stem 28 passes through the first hole 20, the main valve chamber 21, and the second hole 22, with its axis aligned with the axis of the first hole 20 and the axis of the second hole 22. The valve stem 28 is inserted inside the plug 27. The valve stem 28 is reciprocating inside the main body 14 in the axial direction of the main body 14.

[0021] The valve stem 28 has a projection 29. The projection 29 protrudes annularly from the outer surface of the valve stem 28, specifically from a portion located within the main valve chamber 21. A main valve body 30 is attached to the projection 29. The main valve body 30 is made of rubber. The main valve body 30 is provided annularly around the projection 29, surrounding it. Therefore, the main valve section 11 has a main valve body 30. The main valve body 30 is housed in the main valve chamber 21. The main valve body 30 is movable within the main valve chamber 21 as the valve stem 28 moves.

[0022] The main valve section 11 has a main piston 31. The main piston 31 is provided at the first end of the valve stem 28. The main piston 31 is housed in a first recess 18. The main piston 31 can reciprocate integrally with the valve stem 28 within the first recess 18. The space within the first recess 18 located on the side of the valve stem 28 from the main piston 31 is partitioned by the first recess 18 and the main piston 31, forming a main valve pilot chamber 32. Therefore, the main valve section 11 has a main valve pilot chamber 32.

[0023] The main valve section 11 has a valve body spring 33. The valve body spring 33 is interposed between the second end of the valve stem 28 and the second recess 19. The valve body spring 33 biases the valve stem 28 toward the first recess 18.

[0024] The main valve section 11 has a first valve seat 34 and a second valve seat 35. The first valve seat 34 protrudes annularly into the main valve chamber 21 from the end face of the plug 27 on the main valve chamber 21 side. The second valve seat 35 protrudes annularly into the main valve chamber 21 from around the opening on the main valve chamber 21 side at the second end of the first hole 20. The first valve seat 34 and the second valve seat 35 face each other in the axial direction of the main body 14. Therefore, the first valve seat 34 and the second valve seat 35 are arranged facing each other in the direction of movement of the main valve body 30 within the main valve chamber 21.

[0025] The main valve body 30, by seating on the first valve seat 34, allows communication between the intake port 23 and the discharge port 26 via the main valve chamber 21. Conversely, the main valve body 30, by seating on the second valve seat 35, blocks communication between the intake port 23 and the discharge port 26 via the main valve chamber 21. Thus, the main valve body 30 is a poppet valve. The main valve section 11 intermittently discharges air drawn in from the intake port 23 to the outside through the discharge port 26 when the main valve body 30 is switched.

[0026] <Pilot valve section> The pilot valve section 12 has a body 40. The body 40 has a valve casing 41 and a flow path forming block 42. The valve casing 41 is connected to the main body 13. The valve casing 41 is connected to the end face of the first connecting block 15 opposite to the main body body 14. The valve casing 41 has a casing body 43, a first piston block 44 and a second piston block 45.

[0027] The casing body 43 is cylindrical. The pilot valve section 12 has a valve hole 46. The valve hole 46 is formed in the casing body 43. Therefore, the valve hole 46 is formed in the body 40. The valve hole 46 is circular. The valve hole 46 extends in the longitudinal direction of the casing body 43. The first end of the valve hole 46 opens to a first end face located on one side of the casing body 43 in the axial direction. The second end of the valve hole 46 opens to a second end face located on the other side of the casing body 43 in the axial direction. Therefore, the valve hole 46 penetrates the casing body 43 in the axial direction.

[0028] The pilot valve section 12 has a supply port 47, a first output port 48, a second output port 49, a first discharge port 50, and a second discharge port 51. The supply port 47, the first output port 48, the second output port 49, the first discharge port 50, and the second discharge port 51 are formed in the casing body 43. Therefore, the supply port 47, the first output port 48, the second output port 49, the first discharge port 50, and the second discharge port 51 are formed in the body 40. The supply port 47, the first output port 48, the second output port 49, the first discharge port 50, and the second discharge port 51 are each in communication with a valve hole 46. The first discharge port 50, the first output port 48, the supply port 47, the second output port 49, and the second discharge port 51 are formed in the casing body 43 in this order as you move from the first end to the second end in the axial direction of the casing body 43. The supply port 47, the first output port 48, the second output port 49, the first discharge port 50, and the second discharge port 51 open to the end face of the casing body 43 on the side of the main valve 11. The first output port 48 and the second output port 49 also open to the end face of the casing body 43 on the side opposite to the main valve 11. The first discharge port 50 and the second discharge port 51 are in communication with the outside.

[0029] The first piston block 44 is connected to the first end face of the casing body 43. The first piston block 44 has a first piston housing recess 52. The first piston housing recess 52 opens to the end face of the first piston block 44 that is located on the casing body 43 side.

[0030] The second piston block 45 is connected to the second end face of the casing body 43. The second piston block 45 has a second piston housing recess 53. The second piston housing recess 53 opens to the end face of the second piston block 45 that is located on the casing body 43 side.

[0031] The pilot valve section 12 has a first valve body 54 and a second valve body 55. The first valve body 54 and the second valve body 55 are spool valves. The first valve body 54 and the second valve body 55 are reciprocally housed in the valve bore 46. The first valve body 54 and the second valve body 55 are arranged adjacent to each other in the axial direction of the valve bore 46. The first valve body 54 and the second valve body 55 are housed in the valve bore 46 with the axis of the first valve body 54 and the axis of the second valve body 55 coinciding with each other.

[0032] The pilot valve section 12 includes a first piston 56 and a second piston 57. The first piston 56 is disc-shaped. The first piston 56 is connected to the end of the first valve body 54 opposite to the second valve body 55. Therefore, the first piston 56 is located at the end of the first valve body 54. The first piston 56 moves integrally with the first valve body 54.

[0033] The second piston 57 is disc-shaped. The second piston 57 is connected to the end of the second valve body 55 opposite to the first valve body 54. Therefore, the second piston 57 is located at the end of the second valve body 55. The second piston 57 moves integrally with the second valve body 55. The outer diameter of the first piston 56 and the outer diameter of the second piston 57 are the same.

[0034] The end of the first valve body 54 opposite to the second valve body 55 can move in and out of the valve hole 46 into the first piston housing recess 52. The first piston 56 is housed in the first piston housing recess 52. The first piston 56 is capable of reciprocating within the first piston housing recess 52. The first piston 56 partitions the first pilot chamber 58 within the first piston housing recess 52. Thus, the pilot valve section 12 has the first pilot chamber 58. The first pilot chamber 58 is a space located closer to the bottom wall of the first piston housing recess 52 than the first piston 56 within the first piston housing recess 52. In the first pilot chamber 58, the first piston 56 reciprocates. This causes the first valve body 54 to move. Pilot air is supplied to and discharged from the first pilot chamber 58 to move the first valve body 54. The first piston 56 contacts the bottom wall of the first piston housing recess 52 when the first valve body 54 is fully retracted into the first piston housing recess 52 from the valve hole 46.

[0035] The end of the second valve body 55 opposite to the first valve body 54 can move in and out of the valve hole 46 into the second piston housing recess 53. The second piston 57 is housed in the second piston housing recess 53. The second piston 57 is capable of reciprocating within the second piston housing recess 53. The second piston 57 partitions the second pilot chamber 59 within the second piston housing recess 53. Thus, the pilot valve section 12 has a second pilot chamber 59. The second pilot chamber 59 is a space located closer to the bottom wall of the second piston housing recess 53 than the second piston 57 within the second piston housing recess 53. In the second pilot chamber 59, the second piston 57 reciprocates. This causes the second valve body 55 to move. Pilot air is supplied to and discharged from the second pilot chamber 59 to move the second valve body 55. The second piston 57 contacts the bottom wall of the second piston housing recess 53 when the second valve body 55 is fully retracted into the second piston housing recess 53 from the valve hole 46.

[0036] <Flow channel formation block> As shown in Figures 2 and 3, the flow path forming block 42 has a first block portion 60 and a second block portion 61. The first block portion 60 is rectangular in shape. The first block portion 60 is installed alongside the valve casing 41 and is connected to the end face of the first connecting block 15 opposite to the main body 14. The second block portion 61 is rectangular in shape. The second block portion 61 protrudes from the end of the first block portion 60 on the side surface opposite to the first connecting block 15. The second block portion 61 is connected to the end face of the valve casing 41 opposite to the main body 13.

[0037] As shown in Figure 2, the flow path forming block 42 has a first valve mounting recess 62. The first valve mounting recess 62 is formed in the first block portion 60. The first valve mounting recess 62 opens on the end face of the first block portion 60 opposite to the first connecting block 15.

[0038] As shown in Figure 3, the flow path forming block 42 has a second valve mounting recess 63. The second valve mounting recess 63 is formed in the first block portion 60. The second valve mounting recess 63 opens on the end face of the first block portion 60 opposite to the first connecting block 15.

[0039] <Supply channel> As shown in Figure 1, the pulsed air generator 10 is equipped with a supply channel 64. The supply channel 64 has a first channel 65 and a second channel 66. The first channel 65 is formed in the main body 14. The first end of the first channel 65 communicates with the intake port 23. The second end of the first channel 65 opens to the first end face of the main body 14. The second channel 66 is formed in the first connecting block 15. The first end of the second channel 66 opens to the end face of the first connecting block 15 on the main body 14 side and communicates with the second end of the first channel 65. The second end of the second channel 66 opens to the end face of the first connecting block 15 opposite to the main body 14 and communicates with the supply port 47. In this way, the supply channel 64 connects the intake port 23 and the supply port 47.

[0040] <First connecting channel> The pulse air generator 10 is equipped with a first communication channel 67. The first communication channel 67 is formed in the first connecting block 15. The first end of the first communication channel 67 opens on the end face of the first connecting block 15 opposite to the main body 14 and communicates with the first output port 48. The second end of the first communication channel 67 communicates with the main valve pilot chamber 32. In this way, the first communication channel 67 connects the first output port 48 and the main valve pilot chamber 32.

[0041] <Second connecting channel> The pulse air generator 10 is equipped with a second communication channel 68. The second communication channel 68 has a third channel 69 and a fourth channel 70. The third channel 69 is formed in the second block portion 61 of the channel forming block 42. The first end of the third channel 69 opens to the end face of the second block portion 61 on the valve casing 41 side and communicates with the second output port 49. The second end of the third channel 69 opens to the end face of the second block portion 61 on the valve casing 41 side and to a portion facing the first piston block 44. The fourth channel 70 is formed in the first piston block 44. The first end of the fourth channel 70 opens to the end face of the first piston block 44 on the second block portion 61 side and communicates with the second end of the third channel 69. The second end of the fourth channel 70 communicates with the first pilot chamber 58. Thus, the second communication channel 68 connects the second output port 49 and the first pilot chamber 58.

[0042] <Third connecting channel> As shown in Figure 2, the pulse air generator 10 is equipped with a third communication channel 71. The third communication channel 71 has a fifth channel 72, a sixth channel 73, a seventh channel 74, an eighth channel 75, and a ninth channel 76. The fifth channel 72 is formed in the main body 14. The first end of the fifth channel 72 communicates with the discharge port 26. The second end of the fifth channel 72 opens to the first end face of the main body 14. The sixth channel 73 is formed in the first connecting block 15. The first end of the sixth channel 73 opens to the end face of the first connecting block 15 on the main body 14 side and communicates with the second end of the fifth channel 72. The second end of the sixth channel 73 opens to the end face of the first connecting block 15 opposite to the main body 14.

[0043] The seventh passage 74 is formed in the first block portion 60 of the passage forming block 42. The first end of the seventh passage 74 opens to the end face of the first block portion 60 on the first connecting block 15 side and communicates with the second end of the sixth passage 73. The second end of the seventh passage 74 communicates with the portion of the first valve mounting recess 62 closer to the opening. The eighth passage 75 is formed in the first block portion 60 and the second block portion 61 of the passage forming block 42. The first end of the eighth passage 75 communicates with the portion of the first valve mounting recess 62 closer to the bottom. The second end of the eighth passage 75 opens to the end face of the second block portion 61 on the valve casing 41 side and in a portion facing the second piston block 45. The first valve mounting recess 62 forms part of the third communication passage 71.

[0044] The ninth passage 76 is formed in the second piston block 45. The first end of the ninth passage 76 opens to the end face of the second piston block 45 on the second block portion 61 side and communicates with the second end of the eighth passage 75. The second end of the eighth passage 75 communicates with the second pilot chamber 59. In this way, the third communication passage 71 connects the discharge port 26 and the second pilot chamber 59.

[0045] <Discharge channel> As shown in Figure 3, the pulse air generator 10 is equipped with a discharge channel 77. The discharge channel 77 has a 10th channel 78, an 11th channel 79, and a 12th channel 80. The 10th channel 78 is formed in the first connecting block 15. The first end of the 10th channel 78 opens on the end face of the first connecting block 15 opposite to the main body 14 and communicates with the first discharge port 50. The second end of the 10th channel 78 opens on the end face of the first connecting block 15 opposite to the main body 14 and in a portion facing the first block portion 60 of the channel forming block 42.

[0046] The 11th flow path 79 is formed in the first block section 60. The first end of the 11th flow path 79 opens to the end face of the first block section 60 on the first connecting block 15 side and communicates with the second end of the 10th flow path 78. The second end of the 11th flow path 79 communicates with the bottom of the second valve mounting recess 63. The 12th flow path 80 is formed in the first block section 60. The first end of the 12th flow path 80 communicates with the opening portion of the second valve mounting recess 63. The second end of the 12th flow path 80 communicates with the outside. The second valve mounting recess 63 forms part of the discharge flow path 77. In this way, the discharge flow path 77 communicates the first discharge port 50 with the outside.

[0047] <First Adjustment Valve> As shown in Figure 2, a first control valve 81 is provided in the third communication passage 71. The first control valve 81 is a needle valve. The first control valve 81 is mounted in the first valve mounting recess 62. The first control valve 81 adjusts the flow rate of air discharged from the second pilot chamber 59 to the outside via the third communication passage 71 and the discharge port 26.

[0048] The first regulating valve 81 has a valve housing 82. The valve housing 82 is cylindrical. The valve housing 82 has a valve body insertion hole 83, a regulating valve hole 84, and a communication hole 85. The axes of the valve body insertion hole 83, the regulating valve hole 84, and the communication hole 85 coincide with the axis of the valve housing 82. The valve body insertion hole 83 opens to one axial end face of the valve housing 82. The communication hole 85 opens to the other axial end face of the valve housing 82. The regulating valve hole 84 connects the valve body insertion hole 83 and the communication hole 85. The diameter of the regulating valve hole 84 is smaller than the diameter of the valve body insertion hole 83 and the diameter of the communication hole 85. A nut 86 is press-fitted into the valve body insertion hole 83. The nut 86 is press-fitted into the valve body insertion hole 83 with its axis aligned with the axis of the valve body insertion hole 83.

[0049] The valve housing 82 has a first diameter hole 87 and a second diameter hole 88. The first diameter hole 87 penetrates the valve housing 82 radially. The first diameter hole 87 communicates with the end of the valve body insertion hole 83 on the adjustment valve hole 84 side. The first diameter hole 87 communicates the inside of the valve body insertion hole 83 with the outside of the valve housing 82. The second diameter hole 88 penetrates the valve housing 82 radially. The second diameter hole 88 communicates with the end of the communication hole 85 on the adjustment valve hole 84 side. The second diameter hole 88 communicates the inside of the communication hole 85 with the outside of the valve housing 82.

[0050] The first regulating valve 81 is equipped with a needle valve body 89. The needle valve body 89 is columnar in shape. The needle valve body 89 has an insertion portion 90 and a valve portion 91. The insertion portion 90 is columnar in shape. A part of the insertion portion 90 is a male threaded portion 92. The male threaded portion 92 can be screwed onto a nut 86. The valve portion 91 protrudes from one end face of the insertion portion 90 located in the axial direction. The valve portion 91 is tapered in shape. The tip of the valve portion 91 is inserted into the regulating valve hole 84. The first regulating valve 81 adjusts the amount of insertion of the valve portion 91 into the regulating valve hole 84 by adjusting the screwing position of the male threaded portion 92 with respect to the nut 86. This adjusts the flow rate of air passing through the regulating valve hole 84.

[0051] An operating knob 93 is provided at the end of the insertion portion 90 opposite to the valve portion 91. For example, when the operating knob 93 is rotated in the forward direction, the male threaded portion 92 screws forward against the nut 86. This increases the amount the valve portion 91 is inserted into the adjustment valve hole 84, and the flow rate of air passing through the adjustment valve hole 84 decreases. On the other hand, when the operating knob 93 is rotated in the opposite direction to the forward direction, the male threaded portion 92 screws backward against the nut 86. This decreases the amount the valve portion 91 is inserted into the adjustment valve hole 84, and the flow rate of air passing through the adjustment valve hole 84 increases. The first adjustment valve 81 adjusts the flow rate of air passing through the adjustment valve hole 84 from the second pilot chamber 59 through the ninth passage 76, the eighth passage 75, the inside of the first valve mounting recess 62, and the communication hole 85.

[0052] A lip seal 94 is fitted to the outer circumferential surface of the valve housing 82. The lip seal 94 has a V-shaped cross-section. The lip seal 94 is fitted to the outer circumferential surface of the valve housing 82 in the area between the first diameter hole 87 and the second diameter hole 88.

[0053] The lip seal 94 of the first control valve 81 allows air to flow from the seventh passage 74 into the first valve mounting recess 62 and toward the second diameter hole 88 via the space between the outer circumferential surface of the valve housing 82 and the inner circumferential surface of the first valve mounting recess 62. The lip seal 94 of the first control valve 81 blocks air flow from the eighth passage 75 into the first valve mounting recess 62, passing through the communication hole 85 and the second diameter hole 88 toward the seventh passage 74 via the space between the outer circumferential surface of the valve housing 82 and the inner circumferential surface of the first valve mounting recess 62.

[0054] <Second Adjustment Valve> As shown in Figure 3, a second control valve 95 is provided in the discharge passage 77. The second control valve 95 adjusts the flow rate of air discharged from the main valve pilot chamber 32 to the outside via the first output port 48 and the first discharge port 50. Since the specific configuration of the second control valve 95 is the same as that of the first control valve 81, a detailed explanation of the configuration of the second control valve 95 is omitted, by assigning the same reference numerals as the components of the first control valve 81.

[0055] The second control valve 95 adjusts the flow rate of air passing from the main valve pilot chamber 32 through the first communication passage 67, the first output port 48, the valve hole 46, the first discharge port 50, the tenth passage 78, the eleventh passage 79, the inside of the second valve mounting recess 63, and through the communication hole 85 into the control valve hole 84.

[0056] The lip seal 94 of the second control valve 95 allows air to flow from the 12th passage 80 into the second valve mounting recess 63 and toward the second diameter hole 88 via the space between the outer circumferential surface of the valve housing 82 and the inner circumferential surface of the second valve mounting recess 63. The lip seal 94 of the second control valve 95 blocks air flow from the 11th passage 79 into the second valve mounting recess 63, passing through the communication hole 85 and the second diameter hole 88 toward the 12th passage 80 via the space between the outer circumferential surface of the valve housing 82 and the inner circumferential surface of the second valve mounting recess 63.

[0057] <First and second positions of the first valve body> As shown in Figure 1, the first valve body 54 switches to the first position when air is discharged from the first pilot chamber 58. When the first valve body 54 switches to the first position, it blocks the airflow between the supply port 47 and the first output port 48, and allows the airflow between the first output port 48 and the first discharge port 50.

[0058] As shown in Figure 4, the first valve body 54 switches to the second position when air is supplied to the first pilot chamber 58. When the second valve body 55 switches to the second position, it allows airflow between the supply port 47 and the first output port 48, and blocks airflow between the first output port 48 and the first discharge port 50.

[0059] <Third and fourth positions of the second valve body> As shown in Figure 1, the second valve body 55 switches to the third position when the first valve body 54 switches to the first position. When the second valve body 55 switches to the third position, it allows airflow between the supply port 47 and the second output port 49, and blocks airflow between the second output port 49 and the second discharge port 51.

[0060] As shown in Figure 5, the second valve body 55 switches to the fourth position when the first valve body 54 switches to the second position. When the second valve body 55 switches to the fourth position, it blocks the airflow between the supply port 47 and the second output port 49, and allows the airflow between the second output port 49 and the second discharge port 51.

[0061] <Maintenance Department> As shown in Figure 3, the pulse air generator 10 is equipped with a maintenance unit 96. The maintenance unit 96 is located downstream of the second control valve 95 in the discharge passage 77 and is an on-off valve that opens and closes the discharge passage 77. The maintenance unit 96 is capable of being in a closed state when the first valve body 54 is switched to the second position and the second valve body 55 is switched to the fourth position. When the maintenance unit 96 is in a closed state with the first valve body 54 switched to the second position and the second valve body 55 switched to the fourth position, the state in which the first valve body 54 is switched to the second position and the second valve body 55 is switched to the fourth position is maintained. Therefore, the maintenance unit 96 maintains the state in which the first valve body 54 is switched to the second position and the second valve body 55 is switched to the fourth position. Note that the switching of the maintenance unit 96 from the open state to the closed state is performed by an operator. Unless the operator switches the maintenance unit 96 from the open state to the closed state, the maintenance unit 96 remains in the open state at all times.

[0062] [Effect of the Embodiment] Next, the operation of the embodiment will be described. As shown in Figure 1, in the pulse air generator 10, the first valve body 54 is switched to the first position and the second valve body 55 is switched to the third position. When air is drawn in from the air supply source 25 to the intake port 23, a portion of the air drawn into the intake port 23 is supplied to the supply port 47 via the supply passage 64. The air supplied to the supply port 47 is supplied as pilot air to the first pilot chamber 58 via the valve hole 46, the second output port 49, and the second communication passage 68.

[0063] As shown in Figure 4, when pilot air is supplied to the first pilot chamber 58, the first piston 56 moves toward the second pilot chamber 59. This switches the first valve body 54 from the first position to the second position. When the first valve body 54 is switched to the second position, a portion of the air supplied to the supply port 47 is supplied as pilot air to the main valve pilot chamber 32 via the valve hole 46, the first output port 48, and the first communication passage 67.

[0064] When pilot air is supplied to the main valve pilot chamber 32, the main piston 31 moves toward the second recess 19 against the biasing force of the valve body spring 33. As a result, the main valve body 30 moves from the second valve seat 35 toward the first valve seat 34 and seats toward the first valve seat 34. Once the main valve body 30 is seated toward the first valve seat 34, communication between the intake port 23 and the discharge port 26 via the main valve chamber 21 is permitted, and air is discharged to the outside from the discharge port 26.

[0065] As shown in Figure 2, a portion of the air flowing through the discharge port 26 is supplied as pilot air to the second pilot chamber 59 via the third communication passage 71. As shown in Figure 5, when pilot air is supplied to the second pilot chamber 59, the second piston 57 moves toward the first pilot chamber 58. This switches the second valve body 55 from the third position to the fourth position. When the second valve body 55 is switched to the fourth position, the pilot air in the first pilot chamber 58 is discharged to the outside via the second communication passage 68, the second output port 49, the valve hole 46, and the second discharge port 51.

[0066] As shown in Figure 6, when the pilot air in the first pilot chamber 58 is discharged, the first piston 56 moves until it contacts the bottom wall of the first piston housing recess 52. This switches the first valve body 54 from the second position to the first position.

[0067] As shown in Figure 3, when the first valve body 54 is switched to the first position, pilot air in the main valve pilot chamber 32 is discharged to the outside through the first communication passage 67, the first output port 48, the valve hole 46, the first discharge port 50, and the discharge passage 77. When the pilot air in the main valve pilot chamber 32 is discharged, the biasing force of the valve body spring 33 causes the main piston 31 to move toward the bottom of the first recess 18. As a result, the main valve body 30 moves from the first valve seat 34 toward the second valve seat 35 and seats toward the second valve seat 35. When the main valve body 30 seats toward the second valve seat 35, communication between the intake port 23 and the discharge port 26 via the main valve chamber 21 is blocked, and the discharge of air from the discharge port 26 to the outside is blocked.

[0068] Here, the second control valve 95 adjusts the flow rate of air discharged from the main valve pilot chamber 32 to the outside via the first output port 48 and the first discharge port 50, thereby adjusting the time it takes for air to be discharged from the main valve pilot chamber 32. This adjusts the discharge time during which air is discharged to the outside from the discharge port 26.

[0069] As shown in Figure 7, when the communication between the intake port 23 and the discharge port 26 via the main valve chamber 21 is blocked, the pilot air in the second pilot chamber 59 is discharged to the outside via the third communication passage 71 and the discharge port 26. Here, the first control valve 81 adjusts the flow rate of air discharged from the second pilot chamber 59 to the outside via the third communication passage 71 and the discharge port 26, thereby adjusting the time until air is discharged from the second pilot chamber 59. This adjusts the time during which the discharge of air from the discharge port 26 is blocked.

[0070] In this way, the pilot valve section 12 moves the main valve body 30 by supplying and discharging pilot air to and from the main valve pilot chamber 32. As a result, the pulse air generator 10 intermittently discharges air from the discharge port 26.

[0071] In the following explanation, the discharge time during which air is discharged to the outside from the discharge port 26 may be simply referred to as "discharge time." Similarly, the shut-off time during which air discharge from the discharge port 26 is blocked may also be simply referred to as "shut-off time." Furthermore, the on-duty ratio, which is the ratio of the discharge time during which air is discharged to the outside from the discharge port 26 to the shut-off time during which air discharge from the discharge port 26 is blocked, may also be simply referred to as "on-duty ratio."

[0072] The more the first control valve 81 reduces the flow rate of air discharged from the second pilot chamber 59 to the outside via the third communication passage 71 and the discharge port 26, the longer the shut-off time during which air discharge from the discharge port 26 is blocked. The longer the shut-off time, the smaller the on-duty ratio becomes. The time from when air is discharged from the discharge port 26 until the discharge of air from the discharge port 26 is blocked and then discharged again, excluding the shut-off time, becomes the discharge time during which air is discharged from the discharge port 26. As a result, the on-duty ratio, which is the ratio of the discharge time during which air is discharged to the outside from the discharge port 26 to the shut-off time during which air discharge from the discharge port 26 is blocked, is adjustable.

[0073] Furthermore, the second control valve 95 controls the flow rate of air discharged from the main valve pilot chamber 32 to the outside via the first output port 48 and the first discharge port 50. The lower the flow rate of air, the longer the discharge time during which air is discharged from the discharge port 26. The longer the discharge time, the longer the cycle length, which is the time from when air is discharged from the discharge port 26 until the discharge of air from the discharge port 26 is interrupted and then resumed. In this way, by adjusting the flow rate of air discharged from the main valve pilot chamber 32 to the outside via the first output port 48 and the first discharge port 50 using the second control valve 95, it is possible to set the cycle length to a desired length. As a result, it is possible to adjust the frequency in the pulse air generator 10.

[0074] Furthermore, with the first valve body 54 switched to the second position and the second valve body 55 switched to the fourth position, the maintenance unit 96 is closed. This maintains the state in which the first valve body 54 is switched to the second position and the second valve body 55 is switched to the fourth position. As a result, the pulse air generator 10 maintains the state in which air is discharged to the outside from the discharge port 26.

[0075] [Effects of the Embodiment] The above embodiment can be achieved to obtain the following effects. (1) The first control valve 81 and the second control valve 95 do not adjust the flow rate of air supplied to the pilot chamber, as in the prior art, so the pressure inside the pilot chamber does not gradually increase from atmospheric pressure. Therefore, problems such as unstable operation of the pilot valve section 12 can be avoided. Thus, the length of the cycle, which is the time from when air is discharged from the discharge port 26 until the discharge of air from the discharge port 26 is shut off and then the discharge of air from the discharge port 26 is restarted, can be adjusted with precision. As a result, the pulse air generator 10 can adjust the frequency with precision.

[0076] (2) The main valve body 30 is a poppet valve. This makes it possible to extend the lifespan due to grease depletion compared to, for example, when the main valve body 30 is a spool valve. As a result, the durability of the pulse air generator 10 can be improved.

[0077] (3) The first valve body 54 and the second valve body 55 are spool valves. Thus, the configuration in which the first valve body 54 and the second valve body 55 are spool valves is suitable for the pilot valve section 12.

[0078] (4) The pulse air generator 10 is equipped with a maintenance unit 96. With this, the maintenance unit 96 can maintain the state in which the first valve body 54 is switched to the second position and the second valve body 55 is switched to the fourth position. As a result, the pulse air generator 10 can maintain the state in which air is discharged to the outside from the discharge port 26.

[0079] (5) The maintenance unit 96 is located downstream of the second control valve 95 in the discharge passage 77 and is an on-off valve that opens and closes the discharge passage 77. Thus, the configuration in which the maintenance unit 96 is an on-off valve is suitable for the maintenance unit 96.

[0080] (6) Since the main valve body 30 is a poppet valve, the main valve section 11 can be made smaller compared to, for example, when the main valve body 30 is a spool valve. As a result, the pulse air generator 10 can be made smaller.

[0081] [Example of changes] The above embodiment can be implemented with the following modifications. The above embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0082] In this embodiment, the maintenance unit 96 may be provided with a support member that supports the first piston 56 from the bottom of the first piston housing recess 52 so as to maintain the state in which the first valve body 54 is switched to the second position.

[0083] In this embodiment, the maintenance unit 96 may be provided with a support member that supports the second piston 57 from the bottom of the second piston housing recess 53 so as to maintain the state in which the second valve body 55 is switched to the fourth position.

[0084] In this embodiment, the pulse air generator 10 may be configured without a maintenance unit 96. In this embodiment, the first valve body 54 and the second valve body 55 may be poppet valves.

[0085] In this embodiment, the main valve body 30 may be a spool valve. [Explanation of Symbols]

[0086] 10...Pulse air generator, 11...Main valve section, 12...Pilot valve section, 21...Main valve chamber, 23...Intake port, 26...Discharge port, 30...Main valve body, 32...Main valve pilot chamber, 34...First valve seat, 35...Second valve seat, 40...Body, 46...Valve hole, 47...Supply port, 48...First output port, 49...Second output port, 50...First discharge port, 51...Second discharge port, 54...First valve body, 55...Second valve body, 58...First pilot chamber, 59...Second pilot chamber, 64...Supply passage, 67...First communication passage, 68...Second communication passage, 71...Third communication passage, 77...Discharge passage, 81...First control valve, 95...Second control valve, 96...Maintenance section.

Claims

1. A main valve unit having an intake port, a discharge port, a main valve pilot chamber, a main valve chamber, and a main valve body housed in the main valve chamber, which intermittently discharges air drawn in from the intake port to the outside through the discharge port when the main valve body is switched, A pulse air generator comprising a pilot valve section that moves the main valve body by supplying and discharging pilot air to the main valve pilot chamber, The pilot valve section is The body and A valve hole formed in the body, The body is formed and communicates with the valve holes, respectively, a supply port, a first output port, a second output port, a first discharge port, and a second discharge port, A first valve body and a second valve body are housed in the valve hole so as to be reciprocable, A first pilot chamber through which pilot air is supplied and discharged to move the first valve body, It has a second pilot chamber through which pilot air is supplied and discharged to move the second valve body, The first valve body switches to a first position where, when air is discharged from the first pilot chamber, it blocks the airflow between the supply port and the first output port and allows the airflow between the first output port and the first discharge port; and when air is supplied to the first pilot chamber, it switches to a second position where it allows the airflow between the supply port and the first output port and blocks the airflow between the first output port and the first discharge port. The second valve body switches to a third position when the first valve body switches to the first position, which allows airflow between the supply port and the second output port and blocks airflow between the second output port and the second discharge port, and switches to a fourth position when the first valve body switches to the second position, which blocks airflow between the supply port and the second output port and allows airflow between the second output port and the second discharge port. A supply channel connecting the intake port and the supply port, A first communication channel connecting the first output port and the main valve pilot chamber, A second communication channel connecting the second output port and the first pilot chamber, A third communication channel connecting the discharge port and the second pilot chamber, The device comprises a discharge channel that connects the first discharge port to the outside, The third communication channel is provided with a first control valve for adjusting the flow rate of air discharged from the second pilot chamber to the outside via the discharge port. A pulse air generator characterized in that the discharge channel is provided with a second control valve for adjusting the flow rate of air discharged to the outside from the main valve pilot chamber through the first output port and the first discharge port.

2. The main valve section has a first valve seat and a second valve seat arranged opposite to each other in the direction of movement of the main valve body within the main valve chamber, The pulse air generator according to claim 1, characterized in that the main valve body is a poppet valve that, by seating on the first valve seat, allows communication between the intake port and the discharge port via the main valve chamber, and by seating on the second valve seat, blocks communication between the intake port and the discharge port via the main valve chamber.

3. The pulse air generator according to claim 1 or 2, characterized in that the first valve body and the second valve body are spool valves arranged adjacent to each other in the axial direction of the valve hole.

4. The pulse air generator according to claim 1 or 2, further comprising a maintenance unit that maintains the state in which the first valve body is switched to the second position and the second valve body is switched to the fourth position.

5. The pulse air generator according to claim 4, characterized in that the maintenance unit is provided downstream of the second control valve in the discharge passage and is an on / off valve for opening and closing the discharge passage.

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