Air cylinder fluid circuit

Abstract

To provide a fluid circuit of an air cylinder capable of sufficiently suppressing a temperature rise of the air cylinder even if the air cylinder supplying / discharging air through a throttle is used at high speed and high frequency.SOLUTION: In a fluid circuit of an air cylinder 10 connected to a switch valve 28 attached with exhaust ports 30A and 30B, a head side pressure chamber 22 is connected to the switch valve by first piping 26A, and a rod side pressure chamber 24 is connected to the switch valve by second piping 26B. A first throttle 32A is arranged near a connection place between the first piping and the switch valve or a first output port of the switch valve, and a second throttle 32B is arranged near a connection plate between the second piping and the switch valve or a second output port of the switch valve.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fluid circuit of an air cylinder including a throttle. [Background technology]

[0002] Conventionally, a technique has been known in which a fixed throttle (fixed orifice) is provided in the supply / discharge port of an air cylinder to limit the speed of the air cylinder, and a technique has also been known in which a variable throttle (variable orifice) is provided in the supply / discharge port of an air cylinder to enable the speed of the air cylinder to be adjusted to an optimum value.

[0003] For example, Patent Document 1 describes an air cylinder in which a first speed controller is provided at the opening of a cylinder port portion that supplies and exhausts compressed air to a first cylinder chamber of the air cylinder, and a second speed controller is provided at the opening of a cylinder port portion that supplies and exhausts compressed air to a second cylinder chamber of the air cylinder.

[0004] However, when an air cylinder with a throttled supply / discharge port is operated at high speed and frequency, a large amount of thermal energy accumulates in the cylinder chamber, causing a significant temperature rise in each part of the air cylinder.In this case, if the air cylinder does not have sufficient heat resistance, or if the operating speed or frequency of the air cylinder is higher than expected, the temperature rise in the air cylinder can have an adverse effect on the rubber components of the air cylinder, such as the packing and damper, and the durability of the air cylinder may be impaired. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-44952 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a fluid circuit for an air cylinder that can sufficiently suppress temperature rise in the air cylinder, even when the air cylinder, in which air is supplied and discharged via a throttle, is used at high speed and frequency. [Means for solving the problem]

[0007] The fluid circuit of the air cylinder according to the present invention is connected to a selector valve equipped with an exhaust port, and the air cylinder has a head-side pressure chamber and a rod-side pressure chamber partitioned by a piston, the head-side pressure chamber is connected to a first output port of the selector valve by a first pipe, and the rod-side pressure chamber is connected to a second output port of the selector valve by a second pipe, and the selector valve switches between supplying and discharging air to and from the head-side pressure chamber and the rod-side pressure chamber. A first throttle is disposed at a connection point between the first pipe and the selector valve or near the first output port of the selector valve, and a second throttle is disposed at a connection point between the second pipe and the selector valve or near the second output port of the selector valve.

[0008] According to the fluid circuit of the air cylinder described above, the volume of air in which the heat generated by the throttle accumulates includes the volume of the first pipe and the volume of the second pipe, so the temperature rise of the air is suppressed. In addition, the switching valve is cooled as air is exhausted from the exhaust port, so the temperature rise of the air cylinder is suppressed. [Effects of the Invention]

[0009] In the fluid circuit of the air cylinder according to the present invention, a first throttle is disposed at the connection point between the first pipe and the switching valve or near the first output port of the switching valve, and a second throttle is disposed at the connection point between the second pipe and the switching valve or near the second output port of the switching valve. This not only increases the heat capacity of the air, but also provides a cooling effect, thereby suppressing the temperature rise of the air cylinder. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram for explaining the basic concept of the present invention. [Figure 2] FIG. 1 is a conceptual diagram of Comparative Example 1. [Figure 3] FIG. 10 is a conceptual diagram of Comparative Example 2. [Figure 4] 1 is a table summarizing measurement data relating to the present invention and comparative examples. [Figure 5] 1 is an external view of a fluid circuit of an air cylinder according to a first embodiment of the present invention. FIG. [Figure 6] FIG. 6 is a cross-sectional view of a fluid circuit of the air cylinder of FIG. 5. [Figure 7] FIG. 6 is a cross-sectional view of a fluid circuit of an air cylinder according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] First, the basic concept of the present invention will be explained in comparison with Comparative Example 1 and Comparative Example 2. The present invention provides a restriction (orifice) at the connection point between the piping that supplies and exhausts air to and from the air cylinder and the switching valve or near the output port of the switching valve. The present invention will be explained, including the configuration common to Comparative Example 1 and Comparative Example 2.

[0012] 1, the air cylinder 10 includes a cylinder tube 12, a head cover 14, a rod cover 16, and a piston 18. A head-side pressure chamber 22 provided between the piston 18 and the head cover 14 is connected to a first output port 31A of a switching valve 28 by a first pipe 26A. A rod-side pressure chamber 24 provided between the piston 18 and the rod cover 16 is connected to a second output port 31B of the switching valve 28 by a second pipe 26B. The switching valve 28 is provided with a first exhaust port 30A and a second exhaust port 30B that are open to the atmosphere.

[0013] The switching valve 28 is configured to be switchable between a first position where air from the fluid supply source 38 is supplied to the head-side pressure chamber 22 via the first pipe 26A and the air in the rod-side pressure chamber 24 is released to the atmosphere via the second pipe 26B, and a second position where air from the fluid supply source 38 is supplied to the rod-side pressure chamber 24 via the second pipe 26B and the air in the head-side pressure chamber 22 is released to the atmosphere via the first pipe 26A. When the switching valve 28 is switched to the first position, the piston rod 20 is pushed out, and when the switching valve 28 is switched to the second position, the piston rod 20 is retracted.

[0014] The above is a summary of the commonalities between the present invention and Comparative Examples 1 and 2. In the present invention, a first throttle 32A is provided at the connection point between first pipe 26A and switching valve 28 or near first output port 31A of switching valve 28, and a second throttle 32B is provided at the connection point between second pipe 26B and switching valve 28 or near second output port 31B of switching valve 28.

[0015] In contrast, in Comparative Example 1, as shown in FIG. 2, a first orifice 34A is arranged at the location where the head side pressure chamber 22 is connected to the first pipe 26A (head side port), and a second orifice 34B is arranged at the location where the rod side pressure chamber 24 is connected to the second pipe 26B (rod side port).

[0016] 3, a first orifice 36A is provided midway through the first pipe 26A, and a second orifice 36B is provided midway through the second pipe 26B. In Comparative Example 2, the portion of the first pipe 26A from the first orifice 36A to the air cylinder 10 is referred to as the "downstream portion of the first pipe 26A," and the portion of the second pipe 26B from the second orifice 36B to the air cylinder 10 is referred to as the "downstream portion of the second pipe 26B."

[0017] Next, the generation and transfer of heat in Comparative Example 1 and the accompanying temperature rise in the air cylinder 10 will be described.

[0018] During the extrusion process of the piston rod 20, air passes through the first orifice 34A and fills the head-side pressure chamber 22. As the air passes through the first orifice 34A, part of the energy of the air is converted into thermal energy. This heat increases the temperature of the air and enters the head-side pressure chamber 22 together with the air. It is also transferred to the components of the air cylinder 10, such as the head cover 14, using the air as a medium, increasing their temperatures. Some of the heat is also transferred from the first orifice 34A to the components of the air cylinder 10 by thermal conduction. Heat is also generated when the air in the rod-side pressure chamber 24 passes through the second orifice 34B during the extrusion process of the piston rod 20, but this heat has little effect on the air cylinder 10.

[0019] During the retraction stroke of the piston rod 20, air passes through the second orifice 34B and fills the rod-side pressure chamber 24. As the air passes through the second orifice 34B, part of the energy of the air is converted into thermal energy. This heat enters the rod-side pressure chamber 24 together with the air, raising the temperature of the air, and is also transferred to the components of the air cylinder 10, such as the rod cover 16, using the air as a medium, raising their temperatures. Some of the heat is also transferred from the second orifice 34B to the components of the air cylinder 10 by thermal conduction. Heat is also generated when the air in the head-side pressure chamber 22 passes through the first orifice 34A during the retraction stroke of the piston rod 20, but this heat has little effect on the air cylinder 10.

[0020] Part of the heat that enters and accumulates in the head-side pressure chamber 22 during the extrusion stroke of the piston rod 20 is released together with air from the first orifice 34A toward the first piping 26A during the subsequent retraction stroke of the piston rod 20. Part of the heat that enters and accumulates in the rod-side pressure chamber 24 during the retraction stroke of the piston rod 20 is released together with air from the second orifice 34B toward the second piping 26B during the subsequent extrusion stroke of the piston rod 20.

[0021] In this way, heat generated during the extension and retraction of the piston rod 20 accumulates to a certain extent in the air cylinder 10. As the piston 18 repeats reciprocating motion, the temperature of the air cylinder 10 rises until the amount of heat dissipated by the air cylinder 10, which is mainly due to natural heat dissipation, balances with the amount of heat received by the air cylinder 10. In Comparative Example 1, the air cylinder 10 can become extremely hot.

[0022] Next, the generation and transfer of heat and the accompanying temperature rise of the air cylinder 10 in Comparative Example 2 will be described.

[0023] During the extrusion process of the piston rod 20, air passes through the first orifice 36A and fills the downstream portion of the first pipe 26A and the head-side pressure chamber 22. As the air passes through the first orifice 36A, part of the energy of the air is converted into thermal energy. This heat increases the temperature of the air and is carried along with the air to the downstream portion of the first pipe 26A and the head-side pressure chamber 22. It is also transferred via the air to components of the air cylinder 10, such as the head cover 14, thereby increasing their temperatures. Some of the heat is also transferred from the first orifice 36A to the first pipe 26A by thermal conduction, and then from the first pipe 26A to the components of the air cylinder 10.

[0024] During the retraction stroke of the piston rod 20, air passes through the second orifice 36B and fills the downstream portion of the second piping 26B and the rod-side pressure chamber 24. As the air passes through the second orifice 36B, part of the energy of the air is converted into thermal energy. This heat increases the temperature of the air and is carried along with the air to the downstream portion of the second piping 26B and the rod-side pressure chamber 24. It is also transferred via the air to components of the air cylinder 10, such as the rod cover 16, thereby increasing their temperatures. In addition, part of the heat is transferred from the second orifice 36B to the second piping 26B by thermal conduction, and then from the second piping 26B to the components of the air cylinder 10.

[0025] In this way, the heat generated during the pushing and retracting processes of the piston rod 20 is not only accumulated in the air cylinder 10, but is also accumulated in a share in the downstream portion of the first pipe 26A and the downstream portion of the second pipe 26B.

[0026] As the piston 18 repeats reciprocating motion, the temperature of the air cylinder 10 rises until the amount of heat dissipated by the air cylinder 10, which is mainly due to natural heat dissipation, balances with the amount of heat received by the air cylinder 10. In this case, the volume of the air that absorbs the generated heat is the sum of the volume of the head-side pressure chamber 22 and the volume of the rod-side pressure chamber 24, as well as the volume of the downstream portion of the first piping 26A and the volume of the downstream portion of the second piping 26B. Therefore, compared to Comparative Example 1, the heat capacity of the air is greater, so the air does not become as hot as in Comparative Example 1, and the air cylinder 10 does not become as hot as in Comparative Example 1.

[0027] Next, the generation, transfer and radiation (cooling) of heat in the present invention and the accompanying temperature rise of the air cylinder 10 will be described.

[0028] During the extrusion process of the piston rod 20, air passes through the first orifice 32A and fills the entire first pipe 26A and the head-side pressure chamber 22. As the air passes through the first orifice 32A, part of the energy of the air is converted into thermal energy. This heat increases the temperature of the air and is carried along with the air to the first pipe 26A and the head-side pressure chamber 22. It is also transferred via the air to the components of the air cylinder 10, such as the head cover 14, thereby increasing their temperatures. Some of the heat is also transferred from the first orifice 32A to the first pipe 26A by thermal conduction, and then from the first pipe 26A to the components of the air cylinder 10.

[0029] During the extrusion process of the piston rod 20, the air that had filled the second pipe 26B and the rod-side pressure chamber 24 passes through the second orifice 32B and is discharged into the atmosphere from the second exhaust port 30B attached to the switching valve 28. When the air is discharged from the second exhaust port 30B, it rapidly expands in an adiabatic state and its temperature drops. This cools the switching valve 28, and also the first orifice 32A and the second orifice 32B. This has the effect of cooling the first pipe 26A, the second pipe 26B, and the air therein. Note that, during the extrusion process of the piston rod 20, heat is generated when the air that had filled the second pipe 26B and the rod-side pressure chamber 24 passes through the second orifice 32B, but this heat does not affect the air cylinder 10.

[0030] During the retraction stroke of the piston rod 20, air passes through the second orifice 32B and fills the entire second pipe 26B and the rod-side pressure chamber 24. As the air passes through the second orifice 32B, some of the energy of the air is converted into thermal energy. This heat increases the temperature of the air and is carried along with the air to the second pipe 26B and the rod-side pressure chamber 24. It is also transferred via the air to the components of the air cylinder 10, such as the rod cover 16, thereby increasing their temperatures. Some of the heat is transferred from the second orifice 32B to the second pipe 26B by thermal conduction, and then from the second pipe 26B to the components of the air cylinder 10.

[0031] During the retraction of the piston rod 20, the air that filled the first pipe 26A and the head-side pressure chamber 22 passes through the first orifice 32A and is discharged into the atmosphere from the first exhaust port 30A attached to the switching valve 28. When the air is discharged from the first exhaust port 30A, it rapidly expands in an adiabatic state and its temperature drops. This cools the switching valve 28, and also the first orifice 32A and the second orifice 32B. This has the effect of cooling the first pipe 26A, the second pipe 26B, and the air therein. Note that, during the retraction of the piston rod 20, heat is generated when the air that filled the first pipe 26A and the head-side pressure chamber 22 passes through the first orifice 32A, but this heat does not affect the air cylinder 10.

[0032] In this way, the heat generated in association with the pushing-out and retracting strokes of the piston rod 20 is accumulated not only in the air cylinder 10, but also in the entire first pipe 26A and the entire second pipe 26B. In addition, the switching valve 28 is cooled in association with the pushing-out and retracting strokes of the piston rod 20, which has the effect of cooling the first pipe 26A, the second pipe 26B, and the air therein.

[0033] As the piston 18 repeatedly reciprocates, the temperature of the air cylinder 10 rises until the amount of heat dissipated by the air cylinder 10 is balanced with the amount of heat received by the air cylinder 10. In the present invention, the volume of the air that absorbs the generated heat is the sum of the volume of the head-side pressure chamber 22 and the volume of the rod-side pressure chamber 24, as well as the volume of the entire first pipe 26A and the entire second pipe 26B, resulting in a greater heat capacity of the air than in Comparative Example 2. In addition, because the first and second orifices 32A and 32B are directly connected to the switching valve 28, the first and second pipes 26A and 26B and the air therein are cooled. Therefore, the air is less likely to become hot, and the temperature rise in the air cylinder 10 is sufficiently suppressed.

[0034] For the fluid circuits of the air cylinders 10 of the present invention, Comparative Example 1, and Comparative Example 2, an experiment was conducted to determine the temperature of each part of the cylinder tube 12, head cover 14, rod cover 16, switching valve 28, first orifices 32A, 34A, 36A, and second orifices 32B, 34B, 36B when the piston 18 was caused to reciprocate (vibrate) at a predetermined period.

[0035] The air cylinder 10 used had a cylinder tube 12 with an inner diameter of 10 mm and a piston 18 stroke of 45 mm, and the first and second pipes 26A, 26B had inner diameters of 4 mm and lengths of 500 mm. The orifice diameters of the first orifices 32A, 34A, and 36A were 1.1 mm, and the orifice diameters of the second orifices 32B, 34B, and 36B were 1.8 mm. The tactile time of the switching valve 28 was 35 ms, from the first position to the second position and from the second position to the first position.

[0036] In the present invention, the distance from the air cylinder 10 to the first orifice and the distance from the air cylinder 10 to the second orifice are 500 mm, which is the same as the lengths of the first pipe 26A and the second pipe 26B, and are zero in the case of Comparative Example 1. In Comparative Example 2, the first orifice 36A is disposed exactly in the center of the first pipe 26A, and the second orifice 36B is disposed exactly in the center of the second pipe 26B, so that the distance is 250 mm.

[0037] The temperature (maximum temperature) of each part was measured when the air cylinder 10 was operated for 5 minutes at room temperature of 25° C. A table summarizing the measurement results is shown in FIG.

[0038] In Comparative Example 1, the cylinder tube 12 rose to 100°C, the head cover 14 rose to 111°C, and the rod cover 16 rose to 63°C. In Comparative Example 2, the cylinder tube 12 rose to 64°C, the head cover 14 rose to 50°C, and the rod cover 16 rose to 46°C.

[0039] In contrast, in the present invention, the temperature of the cylinder tube 12 rose only to 56°C, and the temperatures of the head cover 14 and rod cover 16 rose only to 39°C. It can be seen that the present invention sufficiently suppresses the temperature rise of the components of the air cylinder 10.

[0040] In Comparative Example 1, the temperature of the switching valve 28 was 17°C, which is lower than room temperature, and it is understood that the switching valve 28 was cooled to a considerable extent. Also, in Comparative Example 1, the temperature of the head cover 14 was significantly higher than the temperature of the rod cover 16, which indicates that the influence of the heat generated in the first orifice 34A, which has a smaller orifice diameter than the second orifice 34B, was significant.

[0041] Next, a fluid circuit of an air cylinder according to the present invention will be described with reference to several specific embodiments with reference to the accompanying drawings.

[0042] (First embodiment) The fluid circuit 40 of the air cylinder according to the first embodiment of the present invention will be described with reference to Figures 5 and 6. The fluid circuit 40 of the air cylinder includes an air cylinder 42, a first pipe 58, a second pipe 60, a first speed controller 62 (first throttle), a second speed controller 64 (second throttle), and a switching valve 66.

[0043] The switching valve 66 has a spool valve element 70 slidably mounted in a valve hole 68a formed inside a body 68. The body 68 is provided with a first exhaust port 72 and a second exhaust port 74 each equipped with a silencer. The body 68 also has a supply port 68b connected to a fluid supply source (not shown), a first output port 68c connected to the first speed controller 62, and a second output port 68d connected to the second speed controller 64.

[0044] The first speed controller 62, which is a variable throttle, is composed of a valve body 62a having an air passage 62c therein, and a needle valve element 62b inserted into the air passage 62c. A knob 62d is provided at the end of the needle valve element 62b extending outward from the valve body 62a, and the area of ​​the air passage 62c can be changed by rotating the knob 62d. The valve body 62a is L-shaped, with one end connected to a first output port 68c of the switching valve 66 and the other end connected to the first piping 58.

[0045] The second speed controller 64, which is a variable throttle, is also composed of a valve body 64a and a needle valve body 64b, similar to the first speed controller 62, and one end of the valve body 64a is connected to the second output port 68d of the switching valve 66, and the other end of the valve body 64a is connected to the second piping 60.

[0046] The air cylinder 42 includes a cylinder tube 44, a head cover 46, a rod cover 48, a piston 50, and a piston rod 52. A head-side pressure chamber 54 provided between the piston 50 and the head cover 46 is connected to a first pipe 58, and a rod-side pressure chamber 56 provided between the piston 50 and the rod cover 48 is connected to a second pipe 60.

[0047] The switching valve 66 is configured to be switchable between a first position where the piston rod 52 is pushed out and a second position where the piston rod 52 is retracted, depending on the sliding position of the spool valve element 70. The switching valve 66 shown in Figure 6 is in a state where it is switched to the first position.

[0048] When the switching valve 66 is in the first position, the air passage 62c of the first speed controller 62 communicates with the supply port 68b, and the air passage 64c of the second speed controller 64 communicates with the second exhaust port 74. At this time, air from the fluid supply source passes through the first speed controller 62 and is supplied to the first pipe 58 and the head-side pressure chamber 54, and air from the second pipe 60 and the rod-side pressure chamber 56 passes through the second speed controller 64 and is exhausted from the second exhaust port 74 to the atmosphere.

[0049] When the switching valve 66 is in the second position, the air passage 64c of the second speed controller 64 communicates with the supply port 68b, and the air passage 62c of the first speed controller 62 communicates with the first exhaust port 72. At this time, air from the fluid supply source passes through the second speed controller 64 and is supplied to the second piping 60 and the rod-side pressure chamber 56, and air in the first piping 58 and the head-side pressure chamber 54 passes through the first speed controller 62 and is exhausted from the first exhaust port 72 to the atmosphere.

[0050] Heat generated when air passes through the first speed controller 62 during the extension stroke of the piston rod 52 is carried along with the air to the first pipe 58 and the head-side pressure chamber 54, and heat generated when air passes through the second speed controller 64 during the retraction stroke of the piston rod 52 is carried along with the air to the second pipe 60 and the rod-side pressure chamber 56. In other words, the volume of the air that receives the generated heat is not only the volume of the head-side pressure chamber 54 and the volume of the rod-side pressure chamber 56, but also the volume of the entire first pipe 58 and the entire second pipe 60, and the heat capacity of the air is large. Therefore, the air does not easily become hot, and a temperature rise in the air cylinder 42 is suppressed.

[0051] Furthermore, when air is discharged from the second exhaust port 74 during the pushing stroke of the piston rod 52, the temperature of the air drops due to adiabatic expansion, and when air is discharged from the first exhaust port 72 during the retracting stroke of the piston rod 52, the temperature of the air also drops due to adiabatic expansion. This cools the switching valve 66, and also cools the first speed controller 62 and the second speed controller 64. This has the effect of cooling the first pipe 58, the second pipe 60, and the air therein. Therefore, the temperature rise of the air cylinder 42 is suppressed.

[0052] According to the present embodiment, the volume of the air in which heat generated in the first speed controller 62 and the second speed controller 64 accumulates includes the volume of the first piping 58 and the volume of the second piping 60, so a temperature rise in the air is suppressed, and a temperature rise in the air cylinder 42 is suppressed. In addition, the switching valve 66 is cooled as air is exhausted from the first exhaust port 72 and the second exhaust port 74, so a temperature rise in the air cylinder 42 is suppressed.

[0053] In this embodiment, the first and second throttles are variable throttles, but they may also be fixed throttles. Furthermore, the first and second throttles may be of a type that throttles the air flowing into the air cylinder but does not throttle the air being discharged from the air cylinder, i.e., meter-in throttles. Furthermore, although two exhaust ports are provided on the switching valve 66, they may be combined into a single exhaust port.

[0054] (Second embodiment) Next, a fluid circuit 80 of an air cylinder according to a second embodiment of the present invention will be described with reference to Fig. 7. Note that components that are the same as or equivalent to those in the fluid circuit 40 of the air cylinder described above will be given the same reference numerals, and detailed description thereof will be omitted.

[0055] The fluid circuit 80 of the air cylinder includes the air cylinder 42, the first pipe 58, the second pipe 60, the first joint 86, the second joint 88, and the switching valve 66. The first joint 86 is an L-shaped joint provided to connect the first output port 68c of the switching valve 66 to the first pipe 58, and the second joint 88 is an L-shaped joint provided to connect the second output port 68d of the switching valve 66 to the second pipe 60.

[0056] The first and second throttles 82 and 84, which are fixed throttles, are built into the switching valve 66. Specifically, the first throttle 82 is provided near the first output port 68c of the switching valve 66, between a predetermined portion of the valve hole 68a of the body 68 and the first output port 68c. The second throttle 84 is provided near the second output port 68d of the switching valve 66, between a predetermined portion of the valve hole 68a of the body 68 and the second output port 68d.

[0057] According to the present embodiment, the volume of the air in which heat generated in the first orifice 82 and the second orifice 84 accumulates includes the volume of the first piping 58 and the volume of the second piping 60, so a temperature rise in the air is suppressed, and a temperature rise in the air cylinder 42 is suppressed. In addition, the switching valve 66 incorporating the first orifice 82 and the second orifice 84 is cooled as air is exhausted from the first exhaust port 72 and the second exhaust port 74, so a temperature rise in the air cylinder 42 is suppressed.

[0058] The present invention defines the first and second throttles as the portions of the flow path from the air cylinder to the switching valve that have the smallest flow area and the greatest throttling effect, and also includes cases where another throttle with a larger flow area than the first and second throttles is provided in the flow path from the air cylinder to the switching valve.

[0059] The fluid circuit of the air cylinder according to the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted within the scope of the gist of the present invention. [Explanation of symbols]

[0060] 10, 42...Air cylinder 18, 50...Piston 22, 54...Head side pressure chamber 24, 56...Rod side pressure chamber 26A, 58...First pipe 26B, 60...Second pipe 28, 66...Switching valve 30A, 72...First exhaust port (exhaust port) 30B, 74...Second exhaust port (exhaust port) 31A, 68c...First output port 31B, 68d...Second output port 32A...First aperture 32B... Second throttle 40, 80... Air cylinder fluid circuit 62...1st speed controller (1st aperture) 64...Second speed controller (second aperture) 82...First aperture 84...Second aperture

Claims

1. A fluid circuit of an air cylinder connected to a switching valve having an exhaust port, the air cylinder includes a head side pressure chamber and a rod side pressure chamber partitioned by a piston, the head side pressure chamber is connected to a first output port of the switching valve by a first pipe, the rod side pressure chamber is connected to a second output port of the switching valve by a second pipe, and the switching valve switches between supplying and discharging air to and from the head side pressure chamber and the rod side pressure chamber, A fluid circuit of an air cylinder, wherein a first throttle is disposed between the valve hole of the switching valve and the first output port, and a second throttle is disposed between the valve hole and the second output port.

2. 2. The fluid circuit of claim 1, A fluid circuit of an air cylinder, wherein the first throttle and the second throttle are fixed throttles.

3. 2. The fluid circuit of claim 1, The first and second throttles are meter-in throttles in the fluid circuit of an air cylinder.

Images