Cylinder, top end cover and rod end cover

Abstract

A cylinder (10) is provided with a flow controller (24, 24A) built into a top end cover (14) and a rod end cover (16), wherein the flow controller (24, 24A) comprises a first flow adjustment section (28) connected between a port (14a, 16a) and a cylinder chamber (12c), a second flow adjustment section (32) arranged in parallel with the first flow adjustment section (28), and a pilot check valve (38) connected in series with the second flow adjustment section (32). The pilot check valve (38) is switched to a state of allowing exhaust air from the cylinder chamber (12c) to pass through and a state of preventing exhaust air from passing through by the pressure of pilot air.

Description

Technical Field

[0001] The invention relates to a cylinder, a top side end cover and a rod side end cover. Background Art

[0002] Conventionally, an impact mitigation mechanism is used, which is a cushioning material made of soft resin such as rubber or polyurethane, an oil damper, etc., installed at the end of the cylinder to mitigate the impact at the end of the stroke. However, the impact mitigation mechanism that mechanically mitigates the impact of the cylinder has a limit on the number of operations and requires regular maintenance.

[0003] In order to solve this inconvenience, Japanese Patent No. 5578502 discloses a speed controller (flow rate controller) that reduces the operating speed of the cylinder by throttling the exhaust gas from the cylinder near the end of the stroke.

[0004] However, the conventional flow controller is an external part connected to the port of the cylinder, which increases the number of parts of the cylinder drive device and complicates the device structure of the drive device. In addition, due to the complex structure, when the top end cover and the rod end cover of the cylinder are to be integrated, processing becomes difficult and productivity is reduced. Summary of the invention

[0005] An object of the present invention is to provide an air cylinder, a top end cover, and a rod end cover that can simplify the device structure of a drive device and have excellent productivity.

[0006] One viewpoint of the present invention is that the cylinder comprises: a cylinder barrel having a cylinder chamber formed therein; a top end cover, the top end cover closing one end of the cylinder barrel; a rod side end cover, the rod side end cover closing the other end of the cylinder barrel; a piston, the piston sliding in the cylinder chamber; a piston rod, one end of the piston rod being connected to the piston; a port, the port being respectively provided in the top end cover and the rod side end cover; and a flow controller, the flow controller being built into at least one of the top end cover and the rod side end cover, the flow controller comprising: a first flow path, the first flow path connecting the port and the cylinder chamber; a second A flow regulating unit, which is arranged in the first flow path; a second flow path, which is arranged in parallel with the first flow path; a second flow regulating unit, which is arranged in the second flow path; a pilot check valve, which is arranged in series with the second flow regulating unit in the second flow path; and a third flow regulating unit, which supplies and discharges pilot air to the pilot check valve, and the pilot check valve switches to a state of allowing exhaust air discharged from the cylinder chamber to pass through and a state of preventing the exhaust air from passing through according to the pressure of the pilot air.

[0007] Another aspect of the present invention is a top side end cover, which is a top side end cover of the cylinder, covering the end of the top side of the cylinder barrel, and comprising: a port; a first flow path, which is connected to the port and the cylinder chamber of the cylinder; a first flow adjustment unit, which is arranged in the first flow path; a second flow path, which is arranged in parallel with the first flow path; a second flow adjustment unit, which is arranged in the second flow path; a pilot check valve, which is arranged in the second flow path and connected in series with the second flow adjustment unit; and a third flow adjustment unit, which supplies and discharges pilot air to the pilot check valve, and the pilot check valve switches to a state of allowing exhaust air discharged from the cylinder chamber to pass through and a state of preventing the exhaust air from passing through according to the pressure of the pilot air.

[0008] Another aspect of the present invention is that the rod side end cover is the rod side end cover of the cylinder, which covers the end of the rod side of the cylinder tube and comprises: a port; a first flow path, which is connected to the port and the cylinder chamber of the cylinder; a first flow adjustment unit, which is arranged in the first flow path; a second flow path, which is arranged in parallel with the first flow path; a second flow adjustment unit, which is arranged in the second flow path; a pilot check valve, which is arranged in the second flow path and connected in series with the second flow adjustment unit; and a third flow adjustment unit, which supplies and discharges pilot air to the pilot check valve, and the pilot check valve switches to a state of allowing exhaust air discharged from the cylinder chamber to pass through and a state of preventing the exhaust air from passing through according to the pressure of the pilot air.

[0009] According to the air cylinder, the top side cover, and the rod side cover of the above-described viewpoint, the device structure of the driving device can be simplified, and since the structure is simplified, the productivity is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a perspective view of a cylinder according to an embodiment of the present invention.

[0011] Figure 2 yes Figure 1 Fluid circuit diagram of the cylinder and its driving device.

[0012] Figure 3A yes Figure 1 A three-dimensional view of the rod side end cap, Figure 3B yes Figure 3A A side view of the cylinder barrel side of the rod side end cover.

[0013] Figure 4 yes Figure 3A Top view of the rod-side end cap.

[0014] Figure 5 It is along Figure 3B A cross-sectional view of line VV.

[0015] Figure 6 It is along Figure 3B The cross-sectional view of line VI-VI shows Figure 5 The pilot check valve is open due to the pilot pressure.

[0016] Figure 7 It is along Figure 4 A cross-sectional view taken along line VII-VII.

[0017] Figure 8 It is along Figure 4 A cross-sectional view taken along line VIII-VIII.

[0018] Fig. 9 It is along Figure 4 A cross-sectional view taken along line IX-IX.

[0019] Fig. 10A yes Figure 1 A three-dimensional view of the top end cover, Fig. 10B yes Fig. 10A A side view of the cylinder barrel side of the top end cover.

[0020] Fig.11 yes Fig. 10A A top view of the top end cover.

[0021] Fig.12 It is along Fig.11 A cross-sectional view taken along line XII-XII.

[0022] Fig.13 It means in Figure 1 A fluid circuit diagram showing the movement of a cylinder near the end of its stroke. DETAILED DESCRIPTION

[0023] Hereinafter, preferred embodiments of the present invention will be listed and described in detail with reference to the drawings.

[0024] like Figure 1 As shown, the cylinder 10 is a double-acting cylinder used in an automatic equipment production line, etc. The cylinder 10 includes: a cylindrical cylinder tube 12, a top end cover 14 that seals the top end of the cylinder tube 12, and a rod side end cover 16 that seals the rod side end of the cylinder tube 12. The cylinder tube 12, the top end cover 14, and the rod side end cover 16 are connected in the axial direction by a plurality of connecting rods 22.

[0025] like Figure 2As shown, a piston 18 that separates a cylinder chamber 12c and a piston rod 20 connected to the piston 18 are provided inside the cylinder tube 12. A flow controller 24 on the top side is connected to the top side pressure chamber 12a of the piston 18, and a flow controller 24A on the rod side is connected to the rod side pressure chamber 12b of the piston 18. The flow controller 24 is built into the top side end cover 14 and connected to the top side port 14a. The flow controller 24A is built into the rod side end cover 16 and connected to the rod side port 16a.

[0026] The top flow controller 24 includes a first flow path 26 connecting the top port 14a and the cylinder chamber 12c, and a second flow path 30 provided in parallel with the first flow path 26. A first flow adjustment unit 28 is provided in the first flow path 26. The first flow adjustment unit 28 is composed of a throttle valve that throttles to make the flow rate of air passing through the first flow path 26 variable, and suppresses the movement speed of the piston 18 near the stroke end by mainly throttling the flow rate of the exhaust air.

[0027] The second flow path 30 is provided with a second flow adjustment unit 32 and a pilot check valve 38. The second flow adjustment unit 32 is a throttle valve that can variably adjust the flow rate of air passing through the second flow path 30. The pilot check valve 38 is a check valve that switches whether the exhaust air can pass through using the pressure of the pilot air, and has an inlet 38a, an outlet 38b, and a pilot port 38c. The inlet 38a is connected to the top port 14a side of the second flow path 30, and the outlet 38b is connected to the cylinder chamber 12c side of the second flow path 30. When the pressure of the pilot air is lower than a specified value, the pilot check valve 38 acts as a check valve that allows air from the inlet 38a to the outlet 38b to pass through and blocks the reverse air. In addition, when the pressure of the pilot air is above the specified value, the pilot check valve 38 allows air to pass in two directions, the direction from the inlet 38a to the outlet 38b and the opposite direction.

[0028] The flow controller 24 further includes a third flow path 34 connecting the top port 14a to the cylinder chamber 12c and a pilot air flow path 40 connecting the top port 14a to the pilot port 38c of the pilot check valve 38. A check valve 36 is provided in the third flow path 34. The check valve 36 is connected to allow air flowing from the top port 14a toward the cylinder chamber 12c to pass through and to block the direction of air flowing in the reverse direction. The third flow path 34 and the check valve 36 allow high-pressure air toward the cylinder chamber 12c to flow freely. The third flow path 34 and the check valve 36 may not be independent components as shown in the figure, but may be integrated with the throttle valve of the first flow adjustment unit 28 or the throttle valve of the second flow adjustment unit 32 as a throttle valve with a check valve.

[0029] The pilot air flow path 40 is provided with a third flow regulating unit 42, which can variably adjust the flow rate of the pilot air supplied and discharged to the pilot check valve 38. The third flow regulating unit 42 includes a throttle valve 42a and a check valve 42b connected in parallel with the throttle valve 42a. The check valve 42b is connected so as to allow the air flowing from the top side port 14a toward the pilot check valve 38 to pass through and block the direction of the reverse air, so as to quickly supply the pilot check valve 38 with the pilot air. The throttle valve 42a can variably adjust the flow rate of the pilot air discharged through the pilot air flow path 40, and determine the switching timing of the operation of the pilot check valve 38. The third flow regulating unit 42 can be configured as a throttle valve with a check valve in which the throttle valve 42a and the check valve 42b are integrated.

[0030] The top side flow controller 24 is configured as described above. On the other hand, the rod side flow controller 24A is substantially configured in the same manner as the top side flow controller 24, and therefore, the same components as those of the top side flow controller 24 are denoted by the same reference numerals and detailed descriptions are omitted. However, the components of the rod side flow controller 24A are denoted by A at the end of each reference numeral to distinguish them from the components of the top side flow controller 24.

[0031] Next, the specific structures of the top-side end cover 14 and the rod-side end cover 16 in which the flow controllers 24 and 24A are built-in will be described.

[0032] like Figure 3A As shown, the rod side end cover 16 has a main body 60A formed in a flat rectangular parallelepiped shape. An insertion member 61 for inserting the piston rod 20 is provided at the central portion of the outer end surface 60a of the main body 60A, and connecting holes 22a for fixing the connecting rod 22 are provided at the four corners of the outer end surface 60a of the main body 60A. The connecting hole 22a is penetrated by the main body 60A extending in the axial direction of the piston rod 20. On the upper surface 60b of the rod side end cover 16, a throttle valve constituting the first flow adjustment section 28A, the second flow adjustment section 32A and the third flow adjustment section 42A is provided together with the rod side port 16a.

[0033] like Figure 3B As shown, an annular cylinder mounting groove 64 for mounting the cylinder 12 is provided on the inner end surface 60c of the main body 60A of the rod side end cover 16, and the inner side of the cylinder mounting groove 64 is opposite to the inner side of the rod side pressure chamber 12b. In the center of the cylinder mounting groove 64, an insertion hole 20a for inserting the piston rod 20 is formed, and the first flow path 26A and the valve holes 59a and 59b are opened around the piston rod 20. The check valve 36A is installed in the valve hole 59a, and the pilot check valve 38A is installed in the valve hole 59b.

[0034] like Figure 4As shown, the first flow regulating portion 28A and the second flow regulating portion 32A are arranged on the cylinder tube 12 side of the rod side port 16a, and the third flow regulating portion 42A is arranged on the side of the rod side port 16a. In addition, a pilot check valve 38A is provided inside the main body 60A between the rod side port 16a and the third flow regulating portion 42A.

[0035] One end of the first flow path 26A, the second flow path 30A, the third flow path 34A, and the pilot air flow path 40A opens at the rod side port 16a. Figure 7 As shown, the first flow path 26A opens at the side of the rod side port 16a and extends toward the inlet 28a of the first flow adjustment unit 28A. The first flow adjustment unit 28A is a throttle valve provided in the valve hole 59c, and is provided with a needle 82, which variably blocks the flow path between the inlet 28a opened at the side of the valve hole 59c and the outlet 28b opened at the bottom. The needle 82 is fixed to the valve hole 59c by a threaded mechanism, and when the needle 82 is rotated so that the needle 82 protrudes toward the outlet 28b, the flow path is throttled. The outlet side portion of the first flow path 26A extends to the inner end surface 60c side and opens.

[0036] like Figure 6 As shown, the second flow path 30A is connected to the inlet 38a of the pilot check valve 38A via the second flow adjustment unit 32A. Fig. 9 As shown, the second flow regulating part 32A opens at the upper surface 60b, and the second flow regulating part 32A includes a valve body 94 provided in a valve hole 59d communicating with the second flow path 30A. The valve body 94 is mounted in the valve hole 59d via a threaded mechanism 94a, and the flow rate of the second flow path 30A can be variably adjusted by rotating the valve body 94 so that the valve body 94 protrudes toward the second flow path 30A or the valve body 94 retreats from the second flow path 30A.

[0037] like Figure 7 and Figure 8As shown in FIG. 1 , the third flow path 34A opens at the lower end of the rod-side port 16a, and the third flow path 34A extends toward the inner end surface 60c of the main body 60A and is connected to the check valve 36A. The check valve 36A is inserted into the valve hole 59a opened at the inner end surface 60c, and the check valve 36A includes a valve core 90, a support body 86 fitted in the valve hole 59a and supporting the valve core 90, and a spring 88 connecting the valve core 90 and the support body 86. An inlet 90a formed by reducing the diameter is formed on the inner side of the valve hole 59a, and the valve core 90 is configured to block the inlet 90a. The spring 88 is arranged between the valve core 90 and the support body 86, and applies force to the valve core 90 toward the inlet 90a side. The air flowing in from the inlet 90a side presses the valve core 90 toward the support body 86 side by overcoming the force of the spring 88, and flows into the valve hole 59a, and flows to the rod-side pressure chamber 12b through the opening 86a. When the pressure on the rod-side pressure chamber 12 b side is high, the valve element 90 is pressed against the inlet 90 a , so that the check valve 36A blocks the exhaust air from the rod-side pressure chamber 12 b from passing through.

[0038] like Figure 8 As shown, the pilot air flow path 40A extends from the rod side port 16a toward the inlet 43a of the third flow adjustment part 42A, passes through the third flow adjustment part 42A and is connected to the pilot port 38c. The third flow adjustment part 42A is provided in a valve hole 59e which opens on the upper surface 60b and is connected to the pilot air flow path 40A. The third flow adjustment part 42A is a throttle valve with a one-way valve, and is provided with a flow path component 95a constituting an inner flow path and an outer flow path, a needle 95b capable of variably adjusting the cross-sectional area of ​​the inner flow path, and a sealing component 95c provided on the outer flow path. The sealing component 95c is an elastic component with a substantially V-shaped cross section with a recessed portion toward the outlet 43b side, and the sealing component 95c prevents the passage of air that flows back from the outlet 43b to the inlet 43a in the outer flow path.

[0039] like Figure 5 As shown, one end of the pilot air flow path 40A is connected to the pilot port 38c of the pilot check valve 38A. The pilot check valve 38A is provided in a valve hole 59b having a circular cross section formed by axially penetrating the main body 60A. The valve hole 59b has a piston chamber 65 formed on the outer end face 60a side, a check valve receiving portion 67 formed on the inner end face 60c side, and an intermediate portion 66 formed between the piston chamber 65 and the check valve receiving portion 67. The end of the piston chamber 65 on the outer end face 60a side is sealed by a cover 80. As a pilot port 38c, the pilot air flow path 40A opens in the piston chamber 65 near the cover 80. The air discharge hole 62 opens near the end of the piston chamber 65 on the inner end face 60c side. The air discharge hole 62 opens in the upper surface 60b of the main body 60A.

[0040] The middle portion 66 is formed to have an inner diameter smaller than the piston chamber 65 and the one-way valve housing portion 67, and has a reduced diameter portion 66a formed by reducing the diameter of the middle portion 66 at the boundary portion between the middle portion 66 and the one-way valve housing portion 67. A pilot piston 76 is disposed between the piston chamber 65 and the middle portion 66. The pilot piston 76 has a piston portion 76a that slides inside the piston chamber 65. The piston portion 76a divides the piston chamber 65 into a portion connected to the pilot air flow path 40A and a portion connected to the air exhaust hole 62, and receives the pressure of the pilot air from the pilot air flow path 40A, generating a driving force in the right direction of the figure. As shown in FIG. Figure 6 As shown, the pilot piston 76 protrudes toward the inner end surface 60 c when the pressure of the pilot air increases.

[0041] like Figure 5 As shown in FIG. 1 , a guide portion 76b is formed to protrude from the piston portion 76a toward the middle portion 66. The guide portion 76b is formed to have a diameter slightly smaller than the inner diameter of the middle portion 66 and slides along the middle portion 66. A gasket 76d is provided on the outer periphery of the guide portion 76b to prevent air leakage. The rod portion 76c extends from the end of the guide portion 76b on the side of the check valve accommodating portion 67. The rod portion 76c is formed to have a diameter smaller than the reduced diameter portion 66a of the middle portion 66 and is separated from the inner periphery of the middle portion 66 and the reduced diameter portion 66a.

[0042] The one-way valve housing portion 67 is provided with a valve core 70, a support body 72 supporting the valve core 70, and a return spring 74 urging the valve core 70. The support body 72 is fitted into the end portion of the inner end surface 60c side of the one-way valve housing portion 67. A cylindrical shaft hole 72a is provided at the center of the support body 72, and the shaft portion 70a of the valve core 70 is inserted into the shaft hole 72a. In addition, an opening portion 72b is provided at the outer peripheral portion of the support body 72, and the inside of the one-way valve housing portion 67 and the rod-side pressure chamber 12b can be communicated through the opening portion 72b. The valve core 70 has a closing portion 70b whose diameter is expanded into a disc shape at a portion facing the reduced diameter portion 66a, and the shaft portion 70a extends from the closing portion 70b to the support body 72 side. The closing portion 70b is urged toward the reduced diameter portion 66a side by the return spring 74, and the closing portion 70b covers and closes the reduced diameter portion 66a.

[0043] In the state where the pressure of the pilot air does not work, as shown in the figure, in the pilot check valve 38A, the elastic force of the return spring 74 is used to apply force to the pilot piston 76 toward the cover 80 side. In this state, when high-pressure air flows in from the intermediate portion 66, the closing portion 70b of the valve core 70 is pressed by the high-pressure air and leaves from the reduced diameter portion 66a. Then, the air flowing toward the rod side pressure chamber 12b through the second flow path 30A is passed. On the other hand, when the pressure of the exhaust air of the rod side pressure chamber 12b increases, the valve core 70 prevents the exhaust air from passing because the closing portion 70b applies force to the reduced diameter portion 66a side.

[0044] In addition, if Figure 6 As shown in FIG. 1 , when the pressure of the pilot air is greater than a predetermined value, the pilot piston 76 is displaced toward the one-way valve housing portion 67. In this state, the rod portion 76c of the pilot piston 76 protrudes toward the one-way valve housing portion 67, thereby maintaining the state in which the closing portion 70b of the valve core 70 is separated from the reduced diameter portion 66a. Therefore, the pilot one-way valve 38A allows not only air from the inlet 38a toward the outlet 38b to pass, but also air in the reverse direction to pass.

[0045] The rod side end cover 16 is constructed as described above, and the top side end cover 14 will be described below. Fig. 10A As shown, the top end cover 14 includes a main body 60 that is flat in the axial direction and has a rectangular parallelepiped shape. The connecting hole 22a opens at the outer end surface 60a of the main body 60. In addition, the top port 14a, the first flow rate adjustment portion 28, the second flow rate adjustment portion 32, and the third flow rate adjustment portion 42 are exposed at the upper surface 60b of the main body 60, and the air discharge hole 62 opens at the upper surface 60b of the main body 60.

[0046] like Fig. 10B As shown, a cylinder mounting groove 64 is formed on the inner end surface 60 c of the main body 60 , and the check valve 36 , the pilot check valve 38 , and the opening of the first flow path 26 are provided inside the cylinder mounting groove 64 .

[0047] like Fig.11 As shown in FIG. 1 , in the top end cover 14, as the pilot check valve 38 is arranged close to the center of the main body 60 of the top end cover 14, the third flow adjustment portion 42 is configured to overlap with the upper surface 60b side of the pilot check valve 38. As a result, the path of the pilot air flow path 40 becomes a simpler structure. In addition, the cross-sectional shape of the first flow path 26, the third flow path 34, the first flow adjustment portion 28, and the check valve 36 along the XB-XB line is similar to Figure 7 The first flow path 26A, the third flow path 34A, the first flow adjustment unit 28A, and the check valve 36A on the rod-side end cap 16 side shown in FIG. Fig.11 The cross-sectional shape of the second flow path 30 and the second flow adjustment unit 32 on the XA-XA line is Fig. 9 The cross-sections are the same.

[0048] like Fig.12 As shown in FIG. 1 , in the top cover 14, the pilot air flow path 40 opens at the upper end of the piston chamber 65 and the second flow path 30 opens at the upper end of the intermediate portion 66, which is different from the layout of the rod side cover 16. The other structures of the pilot check valve 38 formed in the top cover 14 are the same as those in FIG. Figure 5 The pilot check valve 38A shown is the same, and therefore the same reference numerals are given to the same structures, and detailed description thereof will be omitted.

[0049] The cylinder 10 , the top end cover 14 , and the rod end cover 16 of the present embodiment are configured as described above, and their functions and operations will be described below.

[0050] like Figure 2 As shown, when the air cylinder 10 is in use, it is connected to a drive device 50, which has a high-pressure air supply source 52, an exhaust port 54, and an action switching valve 56 that switchably connects the high-pressure air supply source 52 and the exhaust port 54 to the top side port 14a and the rod side port 16a. The action switching valve 56 is an electrically switched five-port valve, having a first port 56a to a fifth port 56e. The first port 56a is connected to the top side port 14a, and the second port 56b is connected to the rod side port 16a. In addition, the third port 56c and the fifth port 56e are connected to the exhaust port 54, and the fourth port 56d is connected to the high-pressure air supply source 52. Figure 2 In the first position shown, the first port 56a of the action switching valve 56 is connected to the fourth port 56d, and the second port 56b is connected to the fifth port 56e, thereby connecting the high-pressure air supply source 52 to the top side port 14a, and the exhaust port 54 to the rod side port 16a, and the piston 18 performs a working stroke.

[0051] As shown by arrow A, high-pressure air from the high-pressure air supply source 52 flows from the top port 14a through the top flow controller 24. In the top flow controller 24, the high-pressure air flows to the top pressure chamber 12a through the first flow path 26, the second flow path 30, and the third flow path 34. In this case, the high-pressure air is supplied to the top pressure chamber 12a in a free-flow manner through the third flow path 34 without a throttle valve and the check valve 36 as shown by arrow A.

[0052] In addition, the pilot air is supplied from the pilot port 38c of the pilot check valve 38 through the pilot air flow path 40 and the check valve 42b of the third flow rate adjustment unit 42. Figure 6 As shown, in the pilot check valve 38 on the top side, the rod portion 76 c of the pilot piston 76 protrudes toward the check valve housing portion 67 , and is open to flows in both directions.

[0053] As the piston 18 works, the exhaust air from the rod-side pressure chamber 12b is exhausted through the rod-side flow controller 24A as indicated by arrow B. Since the one-way valve 36A does not allow the exhaust air to pass, the exhaust air is exhausted through the first flow path 26A as indicated by arrow B1 and through the second flow path 30A as indicated by arrow B2. Until the middle of the working stroke, the pilot one-way valve 38A of the second flow path 30A retains the pressure of the pilot air stored in the piston chamber 65 during the last reset stroke. Therefore, as shown in FIG. Figure 6As shown, the pilot piston 76 causes the valve core 70 to continue to move away from the reduced diameter portion 66a, so the pilot check valve 38A allows the exhaust air to pass. Figure 2 In the embodiment, as shown by arrows B1+B2, the exhaust air is discharged at a predetermined flow rate (first control flow) through the first flow path 26A and the second flow path 30A. The movement speed of the piston 18 is limited by the flow rate of the exhaust air.

[0054] In the working stroke, as shown by arrow C2, the pilot air of the pilot check valve 38A gradually flows out through the pilot air flow path 40A and the third flow rate adjustment unit 42A. As the pilot air flows out, the pressure of the pilot air of the pilot check valve 38A gradually decreases.

[0055] Then, at a predetermined time when the piston 18 approaches the end of its stroke, Figure 5 As shown in FIG. 1 , the pilot piston 76 of the pilot check valve 38A is reset to the initial position, and the reduced diameter portion 66a is closed by the valve core 70. Fig.13 As shown by the arrow B1, the exhaust air is switched to the second control flow flowing through the first flow path 26A. In the second control flow, the exhaust air flow is further throttled by the first flow adjustment unit 28A compared to the first control flow, so the movement speed of the piston 18 is suppressed. As a result, the impact of the piston 18 at the end of the stroke can be suppressed.

[0056] After that, the action switching valve 56 is switched from the first position to the second position, the high pressure air supply source 52 is connected to the rod side port 16a, the exhaust port 54 is connected to the top side port 14a, and the reset stroke begins. The action of the reset stroke is just to replace the action of the top side flow controller 24 and the action of the rod side flow controller 24A during the working stroke, which are substantially the same, so the description of the action is omitted.

[0057] The cylinder 10 , the top-side end cover 14 , and the rod-side end cover 16 of the present embodiment provide the following effects.

[0058] The cylinder 10 of this embodiment includes: a cylinder barrel 12, which has a cylinder chamber 12c formed therein; a top end cover 14, which closes one end of the cylinder barrel 12; a rod side end cover 16, which closes the other end of the cylinder barrel 12; a piston 18, which slides in the cylinder chamber 12c; a piston rod 20, one end of which is connected to the piston 18; ports 14a, 16a, which are respectively provided in the top end cover 14 and the rod side end cover 16; and a flow controller 24, which is built into at least one of the top end cover 14 and the rod side end cover 16, and the flow controller 24 includes: a first flow path 26, 26A, which connects the ports 14a, 16a with the cylinder chamber 12c; a first flow adjustment unit 28, 28A, which The flow adjustment parts 28 and 28A are arranged in the first flow path 26 and 26A; the second flow path 30 and 30A are arranged in parallel with the first flow path 26 and 26A; the second flow adjustment parts 32 and 32A are arranged in the second flow path 30 and 30A; the pilot check valve 38 and 38A are arranged in series with the second flow adjustment parts 32 and 32A in the second flow path 30 and 30A; and the third flow adjustment parts 42 and 42A, which supply and discharge pilot air to the pilot check valve 38 and 38A, and the pilot check valve 38 and 38A switches to a state of allowing exhaust air discharged from the cylinder chamber 12c to pass through and a state of preventing exhaust air from passing through according to the pressure of the pilot air.

[0059] According to the above structure, the pilot check valves 38 and 38A with simple structures are used to switch the control flow of the exhaust air, so it is not necessary to use a switching valve such as a shuttle valve or a three-way valve, and the internal structure is simplified. In addition, since there is no need for components requiring precision such as a bushing and a slide column constituting the shuttle valve or the three-way valve, grinding and surface treatment requiring production man-hours are not required, and the manufacturing can be inexpensive.

[0060] In the above-mentioned cylinder 10, it is also possible to further include a one-way valve 36, 36A, which is arranged in parallel with the first flow adjustment unit 28, 28A and allows the air flowing from the port 14a, 16a toward the cylinder chamber 12c to pass through. According to this structure, high-pressure air can be supplied to the cylinder chamber 12c in a free-flowing manner, and the cylinder 10 can be operated at a high speed.

[0061] In the above-described cylinder 10 , the third flow rate adjustment unit 42 , 42A may include a throttle valve 42 a and a check valve 42 b provided in parallel with the throttle valve 42 a and allowing the air flowing toward the pilot port 38 c to pass therethrough.

[0062] The top end cover 14 of the present embodiment is the top end cover 14 of the cylinder 10, and the top end cover 14 covers the top end of the cylinder tube 12, and has: a top port 14a; a first flow path 26, the first flow path 26 is connected to the top port 14a and the cylinder chamber 12c of the cylinder 10; a first flow regulating unit 28, the first flow regulating unit 28 is provided in the first flow path 26; a second flow path 30, the second flow path 30 is provided in parallel with the first flow path 26; and a second flow regulating unit 3 2, the second flow regulating unit 32 is arranged in the second flow path 30; the pilot check valve 38 is arranged in the second flow path 30 and is connected in series with the second flow regulating unit 32; and the third flow regulating unit 4, the third flow regulating unit 4 supplies and discharges the pilot check valve 38, and the pilot check valve 38 is switched to a state of allowing the exhaust air discharged from the cylinder chamber 12c to pass through and a state of preventing the exhaust air from passing through according to the pressure of the pilot air.

[0063] The rod side end cover 16 of the present embodiment is the rod side end cover 16 of the cylinder 10, and the rod side end cover 16 covers the end of the rod side of the cylinder tube 12, and has: a rod side port 16a; a first flow path 26A, which is connected to the rod side port 16a and the cylinder chamber 12c of the cylinder 10; a first flow adjustment unit 28A, which is arranged in the first flow path 26A; a second flow path 30A, which is arranged in parallel with the first flow path 26A; a second flow adjustment unit 32A, The second flow adjustment part 32A is arranged in the second flow path 30A; the pilot check valve 38A, which is arranged in the second flow path 30A and is connected in series with the second flow adjustment part 32A; and the third flow adjustment part 42A, which supplies and discharges pilot air to the pilot check valve 38A, and the pilot check valve 38A switches to a state of allowing exhaust air discharged from the cylinder chamber 12c to pass through and a state of preventing exhaust air from passing through according to the pressure of the pilot air.

[0064] According to the top side end cover 14 and the rod side end cover 16, a simple pilot check valve 38, 38A is used to switch the control flow of the exhaust air, so there is no need to use a switching valve such as a shuttle valve or a three-way valve, the internal structure is simplified, and it can be manufactured inexpensively.

[0065] Although the present invention has been described above by way of preferred embodiments, the present invention is not limited to the embodiments, and various modifications can be made without departing from the gist of the present invention.

Claims

1. A cylinder (10), characterized in that: have: A cylinder barrel (12) having a cylinder chamber (12c) formed therein; A top end cover (14) which closes one end of the cylinder; A rod side end cover (16) which closes the other end of the cylinder; a piston (18) which slides in the cylinder chamber; A piston rod (20), one end of which is connected to the piston and is inserted through the rod-side end cover; Ports (14a, 16a), which are respectively arranged on the top side end cover and the rod side end cover; as well as a flow controller (24) built into at least one of the top end cover and the rod end cover, The flow controller has: a first flow path (26, 26A) connecting the port and the cylinder chamber; a first flow regulating unit (28, 28A), the first flow regulating unit being arranged in the first flow path; a second flow path (30, 30A), the second flow path being arranged in parallel with the first flow path; a second flow rate adjustment unit (32, 32A), the second flow rate adjustment unit being arranged in the second flow path; a pilot check valve (38, 38A) which is arranged in series with the second flow regulating unit in the second flow path and is driven by pilot air supplied to the pilot port (38c); a pilot air flow path (40, 40A) which connects the port with the pilot port and supplies and discharges the pilot air to the pilot check valve; as well as a third flow rate adjustment unit (42, 42A) provided in the pilot air flow path and adjusting the flow rate of the pilot air, The pilot check valve switches between a state allowing exhaust air exhausted from the cylinder chamber to pass therethrough and a state preventing the exhaust air from passing therethrough according to the pressure of the pilot air.

2. The cylinder according to claim 1, characterized in that A one-way valve (36, 36A) is also provided, which is arranged in parallel with the first flow rate adjustment unit and allows the air flowing from the port toward the cylinder chamber to pass therethrough.

3. The cylinder according to claim 1 or 2, characterized in that: The third flow rate adjustment unit includes a throttle valve (42a) and a check valve (42b) which is provided in parallel with the throttle valve and allows the air flowing toward the pilot check valve to pass therethrough.

4. A top end cover is a top end cover of a cylinder, the top end cover covers the end of the top side of the cylinder barrel, characterized in that: have: port; a first flow path communicating with the port and a cylinder chamber of the cylinder; a first flow rate adjustment unit, the first flow rate adjustment unit being disposed in the first flow path; a second flow path, the second flow path being arranged in parallel with the first flow path; a second flow rate adjustment unit, the second flow rate adjustment unit being disposed in the second flow path; a pilot check valve, which is provided in series with the second flow regulating portion in the second flow path and is driven by the pilot air supplied to the pilot port; a pilot air flow path that connects the port with the pilot port and supplies and discharges the pilot air to the pilot check valve; as well as a third flow rate adjustment unit, which is provided in the pilot air flow path and adjusts the flow rate of the pilot air, The pilot check valve switches between a state allowing exhaust air exhausted from the cylinder chamber to pass therethrough and a state preventing the exhaust air from passing therethrough according to the pressure of the pilot air.

5. A rod side end cover, which is a rod side end cover of a cylinder, covers the end of the rod side of the cylinder tube and allows the piston rod to be inserted, characterized in that: have: port; a first flow path communicating with the port and a cylinder chamber of the cylinder; a first flow rate adjustment unit, the first flow rate adjustment unit being disposed in the first flow path; a second flow path, the second flow path being arranged in parallel with the first flow path; a second flow rate adjustment unit, the second flow rate adjustment unit being disposed in the second flow path; a pilot check valve, which is provided in series with the second flow regulating portion in the second flow path and is driven by the pilot air supplied to the pilot port; a pilot air flow path that connects the port with the pilot port and supplies and discharges the pilot air to the pilot check valve; as well as a third flow rate adjustment unit, which is provided in the pilot air flow path and adjusts the flow rate of the pilot air, The pilot check valve switches between a state allowing exhaust air exhausted from the cylinder chamber to pass therethrough and a state preventing the exhaust air from passing therethrough according to the pressure of the pilot air.

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