Flow controller and drive device

Abstract

The flow controller (10) and the drive device (40) include: a first flow path (12) connected between an action switching valve (38) and a cylinder (30) and supplying and discharging air to a cylinder chamber (24) of the cylinder (30); a first flow adjustment unit (16) provided in the first flow path (12); a second flow path (14) provided in parallel with the first flow path (12); a pilot check valve (20) provided in the middle of the second flow path (14); a second flow adjustment unit (18) connected in series with the pilot check valve (20) in the middle of the second flow path (14); a pilot air flow path (21) having one end connected to the action switching valve (38) and the other end connected to a pilot port (20c) of the pilot check valve (20); and a third flow adjustment unit (22) provided in the pilot air flow path (21).

Description

Technical Field

[0001] The invention relates to a flow controller and a driving device for adjusting the action speed of a cylinder. 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 describes a speed controller (flow 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, conventional flow controllers have problems such as a large number of parts and a complex device structure. Summary of the invention

[0005] An object of the present invention is to provide a flow controller and a drive device capable of alleviating the impact of a cylinder with a simple device structure.

[0006] One viewpoint of the present invention is that the flow controller comprises: a first flow path, which is connected between an action switching valve and a cylinder, and supplies and discharges air to a cylinder chamber of the cylinder; a first 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 pilot check valve, which is arranged in the middle of the second flow path, and has an inlet port, an outlet port and a pilot port, wherein the inlet port is connected to a first portion of the action switching valve side of the second flow path, and the outlet port is connected to a second portion of the cylinder side of the second flow path; a second flow regulating unit, which is arranged in the middle of the second flow path and is connected in series with the pilot check valve; a pilot air flow path, one end of which is connected to the action switching valve, and the other end is connected to the pilot port of the pilot check valve; and a third flow regulating unit, which is arranged in the pilot air flow path.

[0007] Another aspect of the present invention is a drive device, comprising an air supply source, which supplies high-pressure air to a cylinder; an exhaust port, which discharges exhaust air from the cylinder; an action switching valve, which switches and connects one of the high-pressure air supply source and the exhaust port to a port of the cylinder; and a flow controller, which is arranged between the action switching valve and the port of the cylinder, and the flow controller comprises: a first flow path, which is connected between the action switching valve and the cylinder, and supplies and discharges air to a cylinder chamber of the cylinder; a first flow regulating unit, which is arranged in the first flow path; and a second flow path, which is connected to the cylinder chamber of the cylinder. flow path is arranged in parallel with the first flow path; a pilot check valve, which is arranged in the middle of the second flow path and has an inlet port, an outlet port and a pilot port, the inlet port is connected to the first part of the action switching valve side of the second flow path, and the outlet port is connected to the second part of the cylinder side of the second flow path; a second flow adjustment unit, which is arranged in the middle of the second flow path and is connected in series with the pilot check valve; a pilot air flow path, one end of which is connected to the action switching valve, and the other end is connected to the pilot port of the pilot check valve; and a third flow adjustment unit, which is arranged in the pilot air flow path.

[0008] According to the flow controller and the driving device of the above-mentioned viewpoint, the impact of the cylinder can be alleviated with a simple device structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a fluid circuit diagram of a flow controller and a drive device for a cylinder according to an embodiment of the present invention.

[0010] Figure 2 is Figure 1 A fluid circuit diagram showing a state in which the flow controller on the rod side is switched to the second control flow during the working stroke among the flow controller and the drive device.

[0011] Figure 3 is Figure 1 A fluid circuit diagram showing the connection relationship between the flow controller and the drive device during the reset stroke. DETAILED DESCRIPTION

[0012] Hereinafter, preferred embodiments of the present invention will be listed and described in detail with reference to the drawings.

[0013] Figure 1The air cylinder 30 shown is a double-acting air cylinder used in an automatic equipment production line, etc., and is driven by a drive device 40 including a pair of flow controllers 10 and 10A, an operation switching valve 38 , a high-pressure air supply source 46 , and an exhaust port 48 .

[0014] The air cylinder 30 includes a piston 26 that partitions a cylinder chamber 24 and a piston rod 28 connected to the piston 26. The cylinder chamber 24 is partitioned into a top pressure chamber 24a and a rod pressure chamber 24b by the piston 26. A top port 32 is provided in the top pressure chamber 24a, and a rod port 32A is provided in the rod pressure chamber 24b.

[0015] The top side port 32 is connected to the top side first flow path 12 and the top side second flow path 14, and the rod side port 32A is connected to the rod side first flow path 12A and the rod side second flow path 14A. The operation switching valve 38 that switchably connects the high-pressure air supply source 46 and the exhaust port 48 is connected to these flow paths. Then, the high-pressure air is supplied to the cylinder 30 and the exhaust air is discharged from the cylinder 30 through the first flow path 12, 12A and the second flow path 14, 14A.

[0016] The top flow controller 10 includes a top first flow path 12 and a top second flow path 14. The first flow path 12 is connected in parallel with the second flow path 14. As shown in the example, one end of the first flow path 12 and the second flow path 14 is connected to the top port 32 by converging at the pipe 34, and the other end of the first flow path 12 and the second flow path 14 is connected to the action switching valve 38 by converging at the pipe 36.

[0017] The first flow path 12 is provided with a first flow rate regulator 16. The first flow rate regulator 16 is a throttle valve and can variably regulate the flow rate of air passing through the first flow path 12. On the other hand, the second flow path 14 is provided with a pilot check valve 20 and a second flow rate regulator 18.

[0018] The pilot check valve 20 has an inlet port 20a, an outlet port 20b, and a pilot port 20c. The inlet port 20a is connected to the first portion 14a on the side of the action switching valve 38 of the second flow path 14, the outlet port 20b is connected to the second portion 14b on the side of the cylinder 30 of the second flow path 14, and the pilot port 20c is connected to the pilot air flow path 21 described later. When the pressure of the pilot air is less than a specified value, the pilot check valve 20 allows the air flowing from the inlet port 20a toward the outlet port 20b to pass and blocks the air flowing in the reverse direction. In addition, when the pressure of the pilot air is greater than a specified value, the pilot check valve 20 allows the air flowing from the inlet port 20a toward the outlet port 20b and the air flowing in the reverse direction to pass.

[0019] The second flow regulating unit 18 is connected in series with the pilot check valve 20. In the illustrated example, it is connected to the first portion 14a of the second flow path 14 (the action switching valve 38 side of the pilot check valve 20), but it is not limited to this, and it can also be connected to the second portion 14b of the second flow path 14 (the cylinder 30 side of the pilot check valve 20). The second flow regulating unit 18 includes a second throttle valve 18a and a check valve 18b arranged in parallel with the second throttle valve 18a. The check valve 18b is connected to allow the air flowing toward the cylinder 30 side to pass through and block the direction of the reverse air. The air flowing toward the action switching valve 38 can be variably adjusted by the second throttle valve 18a. In addition, the second flow regulating unit 18 can also be composed of a throttle valve with a check valve that integrates the second throttle valve 18a and the check valve 18b.

[0020] In addition, the flow controller 10 on the top side is also provided with a pilot air flow path 21 and a third flow adjustment unit 22, and the pilot air flow path 21 supplies and discharges the pilot air of the pilot check valve 20. One end of the pilot air flow path 21 is connected to the action switching valve 38, and the other end is connected to the pilot port 20c of the pilot check valve 20. The third flow adjustment unit 22 is provided in the middle of the pilot air flow path 21, and is provided with a third throttle valve 22a and a check valve 22b provided in parallel with the third throttle valve 22a. The check valve 22b is connected so as to allow the air flowing toward the pilot check valve 20 to pass through and block the direction of the reverse air. The third throttle valve 22a can variably adjust the flow rate of the pilot air discharged from the pilot check valve 20. In addition, the third flow adjustment unit 22 can also be composed of a throttle valve with a check valve that integrates the third throttle valve 22a and the check valve 22b.

[0021] With respect to the flow controller 10 on the top side constructed as described above, the flow controller 10A on the rod side is arranged on the pipeline between the rod side port 32A and the action switching valve 38. Since the flow controller 10A on the rod side is substantially the same as the flow controller 10 on the top side, the same symbols are given to the same components as those of the flow controller 10 on the top side, and their detailed description is omitted. However, with respect to the first flow path 12, the second flow path 14, and the pilot air flow path 21 of the flow controller 10 on the top side, A is marked at the end of each reference symbol on the flow controller 10A side on the rod side for distinction.

[0022] Next, the action switching valve 38 connected to the flow controllers 10 and 10A on the top side and the rod side is described. The action switching valve 38 is a five-port valve that electrically switches the flow path of high-pressure air, and has a first port 41 to a fifth port 45. The first port 41 is connected to the first flow path 12 and the second flow path 14 of the flow controller 10 on the top side. The second port 42 is connected to the first flow path 12A and the second flow path 14A of the flow controller 10A on the rod side. The third port 43 and the fifth port 45 are connected to the exhaust port 48. The fourth port 44 is connected to the high-pressure air supply source 46 that supplies high-pressure air.

[0023] The action switching valve 38 is Figure 1 and Figure 2 The first position shown connects the first port 41 with the fourth port 44, and connects the second port 42 with the fifth port 45. That is, the operation switching valve 38 connects the high-pressure air supply source 46 with the flow controller 10 on the top side, and connects the exhaust port 48 with the flow controller 10A on the rod side in the first position, so that the cylinder 30 performs the working stroke.

[0024] In addition, the actuation switching valve 38 is Figure 3 The second position shown connects the first port 41 with the third port 43, and connects the second port 42 with the fourth port 44. That is, the action switching valve 38 connects the flow controller 10 on the top side with the exhaust port 48 and connects the flow controller 10A on the rod side with the high-pressure air supply source 46 in the second position, so that the cylinder 30 performs the return stroke.

[0025] The flow controllers 10 and 10A and the driving device 40 of the present embodiment are configured as described above, and their operations will be described below.

[0026] like Figure 1 As shown in FIG. 1 , in the working stroke, the fourth port 44 of the action switching valve 38 is connected to the first port 41, and the high-pressure air of the high-pressure air supply source 46 is supplied to the top side flow controller 10. The high-pressure air flows toward the cylinder 30 in the pipe 36 as shown by the arrow A. Then, the high-pressure air is branched into the high-pressure air A1 flowing in the first flow path 12 and the high-pressure air A2 flowing in the second flow path 14.

[0027] The high-pressure air A1 in the first flow path 12 flows at a predetermined flow rate throttled by the first flow rate adjustment unit 16. On the other hand, the high-pressure air A2 in the second flow path 14 flows to the second flow rate adjustment unit 18. The check valve 18b of the second flow rate adjustment unit 18 is connected in a direction to allow the high-pressure air A2 to pass through, so the high-pressure air A2 mainly flows to the pilot check valve 20 through the check valve 18b. The pilot check valve 20 is connected in a direction to allow the high-pressure air A2 to pass through, so the high-pressure air A2 flows toward the cylinder 30 through the pilot check valve 20. In this way, the high-pressure air A2 flows in the second flow path 14 as a free flow that is not throttled by the throttle valve.

[0028] Then, the high-pressure air A1 from the first flow path 12 and the high-pressure air A2 from the second flow path 14 flow into the top-side pressure chamber 24 a of the cylinder 30 , driving the piston 26 toward the rod side.

[0029] In addition, during the working stroke, a part of the high-pressure air flows as pilot air into the pilot air flow path 21 as indicated by arrow A3. The check valve 22b of the third flow rate adjustment unit 22 allows the pilot air flowing toward the pilot check valve 20 to pass quickly and be supplied to the pilot check valve 20. As a result, the pressure of the pilot air of the pilot check valve 20 becomes a high value.

[0030] On the other hand, the exhaust air is exhausted from the rod side pressure chamber 24b of the cylinder 30 through the rod side port 32A. The exhaust air flows in the pipe 34A as shown by the arrow B, and flows into the flow controller 10A on the rod side. In the flow controller 10A, the exhaust air flows into the first flow path 12A and the second flow path 14A. The exhaust air B1 after flowing into the first flow path 12A flows at a predetermined flow rate throttled by the first flow adjustment unit 16.

[0031] In addition, the exhaust air B2 that has flowed into the second flow path 14A flows into the pilot check valve 20. In the pilot check valve 20, the pilot air stored in the last reset stroke remains, and the pressure of the pilot air of the pilot check valve 20 is maintained at a value higher than the specified value until the middle of the working stroke. Therefore, the pilot check valve 20 allows the exhaust air B2 to pass through until the middle of the working stroke. The exhaust air B2 that has passed through the pilot check valve 20 flows in the second flow path 14A at a specified flow rate throttled by the second throttle valve 18a of the second flow adjustment unit 18. In this way, the flow controller 10A on the rod side allows the exhaust air B1+B2 to pass through at a flow rate equivalent to the sum of the flow rate of the exhaust air B1 that has passed through the first flow adjustment unit 16 and the flow rate of the exhaust air B2 that has passed through the second flow adjustment unit 18.

[0032] The exhaust air of the cylinder 30 is discharged at a first control flow obtained by summing the flow rates of the first flow rate regulator 16 and the second flow rate regulator 18 , and the piston 26 moves toward the rod side at a speed limited by the first control flow.

[0033] During the working stroke, the pilot air of the pilot check valve 20 is exhausted through the pilot air flow path 21A of the rod-side flow controller 10A. The pilot air is exhausted gradually through the third throttle valve 22a of the third flow rate adjustment unit 22, and the pressure of the pilot air decreases.

[0034] like Figure 2 As shown, when the piston 26 of the cylinder 30 reaches near the end of the stroke, the pressure of the pilot air of the rod-side pilot check valve 20 is lower than a specified value, and the rod-side pilot check valve 20 closes the second flow path 14A to prevent the exhaust air B2 from passing.

[0035] As the pilot check valve 20 closes the second flow path 14A, only the exhaust air B1 flowing through the first flow adjustment unit 16 is discharged from the cylinder 30. The exhaust air of the cylinder 30 is switched to the second control flow throttled by the first flow adjustment unit 16. The second control flow is throttled more strongly than the first control flow, so the movement speed of the piston 26 of the cylinder 30 is reduced. As a result, the speed of the piston 26 is reduced, and the impact near the stroke end of the piston 26 is alleviated.

[0036] Afterwards, if Figure 3 As shown, the action switching valve 38 is switched to the second position, the flow controller 10 on the top side is connected to the exhaust port 48, and the flow controller 10A on the rod side is connected to the high-pressure air supply source 46. Then, the high-pressure air is introduced into the rod-side pressure chamber 24b of the cylinder 30 through the flow controller 10A, and the exhaust air of the top-side pressure chamber 24a is exhausted through the top-side flow controller 10. Thus, the reset stroke of the piston 26 moving to the top side begins.

[0037] In addition, the action of the flow controller 10 on the top side in the reset stroke is the same as the flow controller 10A on the rod side in the working stroke, and the action of the flow controller 10A on the rod side in the reset stroke is the same as the action of the flow controller 10 on the top side in the working stroke, so the detailed description of these actions is omitted. In the reset stroke, in the flow controller 10 on the top side, the exhaust air is switched from the first control flow passing through the first flow regulator 16 and the second flow regulator 18 to the second control flow flowing only through the first flow regulator 16, and the impact at the stroke end of the piston 26 is alleviated.

[0038] The flow controllers 10 and 10A and the driving device 40 of the present embodiment provide the following effects.

[0039] The flow controller 10, 10A of the present embodiment comprises: a first flow path 12, 12A, which is connected between the action switching valve 38 and the cylinder 30 to supply and discharge air to the cylinder chamber 24 of the cylinder 30; a first flow adjustment unit 16, which is arranged in the first flow path 12, 12A; a second flow path 14, 14A, which is arranged in parallel with the first flow path 12, 12A; a pilot check valve 20, which is arranged in the middle of the second flow path 14, 14A and has an inlet port 20a, an outlet port 20b and a pilot port 20c, and the inlet port 20 a is connected to the first part 14a on the side of the action switching valve 38 of the second flow path 14, 14A, and the outlet port 20b is connected to the second part 14b on the side of the cylinder 30 of the second flow path 14, 14A; a second flow adjustment unit 18, which is arranged in the middle of the second flow path 14, 14A and is connected in series with the pilot check valve 20; a pilot air flow path 21, 21A, one end of which is connected to the action switching valve 38, and the other end is connected to the pilot port 20c of the pilot check valve 20; and a third flow adjustment unit 22, which is arranged in the pilot air flow path 21, 21A.

[0040] According to the above-described configuration, the flow controller 10 , 10A capable of alleviating the impact near the stroke end can be realized with a simple device configuration without using a shuttle valve or a slide valve having a complicated structure.

[0041] In the above-mentioned flow controllers 10, 10A, the pilot check valve 20 may also be constructed to prevent air from flowing from the outlet port 20b toward the inlet port 20a when the pressure of the pilot air is less than a specified value, and to allow air to flow from the outlet port 20b toward the inlet port 20a when the pressure of the pilot air is greater than a specified value.

[0042] In the above-mentioned flow controller 10, 10A, the third flow adjustment unit 22 may include a third throttle valve 22a and a check valve 22b, and the check valve 22b is arranged in parallel with the third throttle valve 22a to allow the air flowing toward the pilot port 20c to pass through and block the air flowing in the reverse direction. The check valve 22b can quickly supply the pilot air to the pilot check valve 20 when the high-pressure air is supplied. In addition, the discharge speed of the pilot air can be variably adjusted by the third throttle valve 22a, so that the timing of switching the flow controller 10, 10A from the first control flow to the second control flow can be easily adjusted.

[0043] In the above-mentioned flow controller 10, 10A, the second flow adjustment unit 18 may include a second throttle valve 18a and a check valve 18b, and the check valve 18b is arranged in parallel with the second throttle valve 18a to allow the air flowing toward the cylinder 30 to pass through and block the air flowing in the reverse direction. When configured as described above, the flow rate of the first control flow can be variably adjusted by the second throttle valve 18a. In addition, the check valve 18b can make the high-pressure air be supplied to the cylinder 30 in a free-flowing manner, and therefore, it is also suitable for the high-speed operation of the corresponding cylinder 30.

[0044] The drive device 40 of the present embodiment comprises: a high-pressure air supply source 46, which supplies high-pressure air to the cylinder 30; an exhaust port 48, which exhausts the exhaust air from the cylinder 30; an action switching valve 38, which switches and connects one of the high-pressure air supply source 46 and the exhaust port 48 to the port of the cylinder 30; and a flow controller 10, 10A, which is arranged between the action switching valve 38 and the port of the cylinder 30, and the flow controller 10, 10A comprises: a first flow path 12, 12A, which is connected between the action switching valve 38 and the cylinder 30 and supplies and discharges air to the cylinder chamber 24 of the cylinder 30; a first flow regulating unit 16, which is arranged in the first flow path 12, 12A; a second flow path 14, 14A, which is connected to the first flow path 14, 14A The flow paths 12 and 12A are arranged in parallel; the pilot check valve 20 is arranged in the middle of the second flow path 14 and 14A, and has an inlet port 20a, an outlet port 20b and a pilot port 20c. The inlet port 20a of the pilot check valve 20 is connected to the first part 14a on the side of the action switching valve 38 of the second flow path 14 and 14A, and the outlet port 20b is connected to the second part 14b on the side of the cylinder 30 of the second flow path 14 and 14A. a second flow regulating unit 18, which is arranged in the middle of the second flow path 14, 14A and is connected in series with the pilot check valve 20; a pilot air flow path 21, 21A, one end of which is connected to the action switching valve 38, and the other end is connected to the pilot port 20c of the pilot check valve 20; and a third flow regulating unit 22, which is arranged in the pilot air flow path 21, 21A.

[0045] According to the above configuration, it is possible to realize the drive device 40 that can mitigate the impact near the stroke end with a simple device structure.

[0046] Although the preferred embodiments of the present invention have been described above, 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 flow controller (10, 10A), characterized in that: have: a first flow path (12, 12A) connected between the action switching valve (38) and the cylinder (30) for supplying and discharging air to a cylinder chamber (24) of the cylinder; a first flow regulating unit (16), the first flow regulating unit being arranged in the first flow path; a second flow path (14, 14A), the second flow path being arranged in parallel with the first flow path; a pilot check valve (20) disposed in the middle of the second flow path, comprising an inlet port (20a), an outlet port (20b) and a pilot port (20c), wherein the inlet port is connected to a first portion (14a) on the action switching valve side of the second flow path, and the outlet port is connected to a second portion (14b) on the cylinder side of the second flow path; a second flow rate regulating unit (18), which is disposed in the middle of the second flow path and is connected in series with the pilot check valve; a pilot air flow path (21, 21A), one end of which is connected to the first flow path between the first flow regulating unit and the action switching valve, and is connected to the second flow path between the second flow regulating unit and the action switching valve, and the other end of which is connected to the pilot port of the pilot check valve; as well as A third flow rate adjustment unit (22), the third flow rate adjustment unit being arranged in the pilot air flow path, When air is supplied to the cylinder, a portion of the air is supplied to the pilot check valve as pilot air. When exhaust air is discharged from the cylinder, the exhaust air is discharged with a first control flow via the first flow regulating part and the second flow regulating part. During the first control flow, the pilot air is discharged from the pilot check valve through the pilot air flow path. When the pressure of the pilot air becomes lower than a specified value, the pilot check valve closes the second flow path, so that the exhaust air is discharged with a second control flow through the first flow regulating part instead of the second flow regulating part.

2. The flow controller according to claim 1, characterized in that: When the pressure of the pilot air is less than a specified value, the pilot check valve blocks the air from flowing from the outlet port toward the inlet port. The pilot check valve allows the air to flow from the outlet port toward the inlet port when the pressure of the pilot air is equal to or greater than a predetermined value.

3. The flow controller according to claim 1, characterized in that: The third flow rate adjustment unit comprises: A third throttle valve (22a); and A one-way valve (22b) is arranged in parallel with the third throttle valve to allow the air flowing toward the pilot port to pass through and prevent the air from flowing in the reverse direction.

4. The flow controller according to any one of claims 1 to 3, characterized in that: The second flow rate adjustment unit comprises: A second throttle valve (18a); and A one-way valve (18b) is arranged in parallel with the second throttle valve to allow the air flowing toward the cylinder to pass through and prevent the air from flowing in the reverse direction.

5. A driving device (40), comprising: a high-pressure air supply source (46) which supplies high-pressure air to the cylinder; an exhaust port (48) for discharging exhaust air from the cylinder; an action switching valve (38) for switchingly connecting one of the high-pressure air supply source and the exhaust port to a port of the cylinder; as well as a flow controller, the flow controller being arranged between the action switching valve and the port of the cylinder, The driving device is characterized in that The flow controller has: a first flow path connected between the action switching valve and the cylinder to supply and discharge air to 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 pilot check valve disposed midway in the second flow path, having an inlet port, an outlet port, and a pilot port, wherein the inlet port is connected to a first portion of the second flow path on the action switching valve side, and the outlet port is connected to a second portion of the second flow path on the cylinder side; a second flow rate regulating unit disposed in the middle of the second flow path and connected in series with the pilot check valve; a pilot air flow path, one end of which is connected to the first flow path between the first flow regulating part and the action switching valve, and is connected to the second flow path between the second flow regulating part and the action switching valve, and the other end of which is connected to the pilot port of the pilot check valve; as well as a third flow rate adjustment unit, the third flow rate adjustment unit being provided in the pilot air flow path, When air is supplied to the cylinder, a portion of the air is supplied to the pilot check valve as pilot air. When exhaust air is discharged from the cylinder, the exhaust air is discharged with a first control flow via the first flow regulating part and the second flow regulating part. During the first control flow, the pilot air is discharged from the pilot check valve through the pilot air flow path. When the pressure of the pilot air becomes lower than a specified value, the pilot check valve closes the second flow path, so that the exhaust air is discharged with a second control flow through the first flow regulating part instead of the second flow regulating part.

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