JP2000274405A - Air cylinder control device and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform low speed operation at a constant speed without knocking, to perform constant speed operation even if a load changes to a piston and a rod, and to prevent sudden speed reduction by mesh-clogging by opening a passage on the outflow inlet side arranged in parallel to two air flow rate stabilizers, and providing passage closing two check valves on the directional control valve side. SOLUTION: A shape of a part for limiting a flow rate of air passing through air flow rate stabilizers is a structure capable of stably passing a fixed quantity of air, so that a speed of a piston is constant, and kocking is not caused. Since a distance capable of controlling a flow rate of the devices is long, side surface resistance is applied to the passing air, and a pressure change in the air is absorbed to stabilize a flow rate constant. Thus, a speed of the piston and a rod does not change. Since a shape of a ventilating part of the devices is not clearance between a surface and a surface, the devices are formed as a structure of hardly hitching chips, so that mesh-clogging by the chips is hardly caused, and sudden speed reduction is not caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention allows a piston and a rod inside a cylinder to be moved by air pressure, thereby enabling a low-speed operation at a constant speed. The present invention relates to an air cylinder control device and a control method that do not generate air.

[0002]

2. Description of the Related Art In a conventional air cylinder control device, a so-called inlet side control is performed in which an inflow side (air supply side) of an air cylinder is a control flow and an outflow side (exhaust side) is a free flow. Things are seen. Further, in the conventional air cylinder control device, a flow rate adjustment using a needle valve which is a kind of a throttle valve is seen (see FIG. 7).

However, conventionally, when low-speed operation at a stable and constant speed is required, an air cylinder is not used and an oil cylinder is usually used.

[0004]

The oil cylinder is expensive and has problems such as odor and oil leakage during use.

[0005] The conventional air cylinder control device described above has no problems of odor or oil leakage, but has the following three problems.

First, it is difficult to operate at a low speed while maintaining a constant speed, which causes knocking. Speed is not flat and there are waves.

Second, when a plus or minus load is applied to the movement direction of the piston and the lot, the operating speed is greatly changed under the influence of the load change. If a load is applied in the movement direction, the speed increases, and if a load is applied in the opposite direction, the speed decreases. Therefore, it is difficult to control the speed accurately.

Thirdly, the speed may suddenly decrease during operation and may not be restored.

[0009] The cause of the above-mentioned problems is in the control system and the valve. In the following, cause 1 of the problem of the control method,
The problems relating to the valve are defined as cause 2, cause 3, and cause 4, cause 1, cause 2, and cause 3 as the cause of the first problem, cause 1, cause 3, and cause 3 as the cause of the second problem. Cause 4 will be described as a cause of the problem.

The first cause is the pressure characteristic between the front and rear cylinder chambers partitioned by the piston of the air cylinder controlled on the inlet side. Since the flow path on the outlet side is open, the cylinder chamber on the outlet side is almost equal to the outside air pressure. Since the flow rate of the flow path on the inlet side is restricted by the valve, the cylinder chamber on the inlet side has a slightly higher air pressure than the cylinder chamber on the outlet side when the valve is open. The piston moves toward the outlet side under the pressure generated by the pressure difference. In the case of the first problem, even if the amount of air flowing into the cylinder chamber on the inlet side is constant, the pressure of the air pushing the piston increases and the speed of the piston pushed by the air increases, so that the frictional resistance of the piston increases. It is considered that this occurs because the pressure of the air pushing the piston decreases and the speed of the piston pushed by the air decreases to increase the frictional resistance of the piston alternately. In the case of the second problem, since the pressure of the air in the cylinder chamber on the inlet side is only slightly higher than the outside air, there is not enough room for the air pressure to be further compressed to a high pressure or to expand to a low pressure by changing the load of the piston. This is related to the fact that the pressure of the air in the cylinder chamber on the outlet side does not change even if the load of the piston changes. In other words, even if the amount of air flowing into the cylinder chamber on the inlet side is constant, if a load is applied in the movement direction of the piston and the rod, the pressure of the air in the cylinder chamber on the inlet side decreases and the air in the cylinder chamber on the outlet side is free. As the piston and rod speed change and rise because they are discharged by the flow, conversely, if a load is applied in the opposite direction to the movement direction of the piston and rod, the air pressure in the inlet-side cylinder chamber rises and the air in the outlet-side cylinder chamber rises. The velocity of the piston and rod is reduced because the free flow suppresses the discharge. Since the air pressure in the cylinder chamber is low as a whole and the air on the inflow side easily expands and contracts, the movement of the piston cannot be completely controlled.

The cause 2 is that the needle valve is a throttle valve, and the gap 2 between the reverse taper member 21 and the taper member 22 which becomes a flow path.
3 is in the form of a ring that is expanded to one side. The flow rate of the air passing through the conical gap 23 slightly oscillates. This is not a structure that allows a fixed amount of air to pass smoothly, but the air expands and contracts when passing, so that the air passes as if it were a fan. This phenomenon is particularly remarkable when the flow rate is reduced. In the case of the first problem, since the flow rate of the air flowing into the cylinder chamber on the inflow side slightly oscillates and the pressure of the air delicately fluctuates, the speed of the cylinder slightly fluctuates and is not constant.

The third reason is that the needle valve is a throttle valve, the length of the gap 23 between the reverse taper member 21 and the taper member 22 is short, and the distance over which the flow rate can be controlled is short (for example, 1 to 2 mm). The time for the air to pass through the gap 23 is also short. When the air is squeezed at a short distance, the passing air expands and contracts. This is a phenomenon that occurs because the air flowing through the connecting pipe 11 is suddenly reduced in flow rate by a short gap 23 like a point and immediately flows out to the connecting pipe 11 again. In addition, the fact that a valve whose air flow rate can be controlled has a short distance can be said to be common. That is, since the side resistance applied to the air flow is small, the flow rate of the velocity air is greatly affected by the pressure change. As the pressure of the air increases, the flow rate increases greatly, and as the pressure decreases, the flow rate decreases. In the case of the first problem,
The air passing through the short gap 23 easily expands and contracts, which contributes to knocking. In the case of the second problem, first, a load change occurs in the piston and the rod, which in turn causes a pressure change in the inflow-side cylinder chamber, which in turn causes a change in the flow rate of the inflow-side needle valve. This in turn promotes a pressure change in the cylinder chamber on the inflow side, which in turn causes a speed change in the piston and rod.

The fourth cause is the flow characteristic of the needle valve which controls the flow by opening and closing the gap 23 between the tapered surface and the reverse tapered surface. Since this valve has a large gap area between the surfaces even if the gap 23 is slightly opened,
Unless the distance between the tapered surface and the reverse tapered surface is very small, low-speed operation cannot be performed (for example, a gap 2 of several microns).
3). Gap 2 between this narrow tapered surface and the reverse tapered surface
Reference numeral 3 denotes a structure in which fine dust is easily clogged, and once clogged, it cannot be easily removed. In the case of the third problem, fine debris such as moisture in the air, oil of valves and cylinders, and wear debris are floating inside the air cylinder, and these fine particles enter the gap 23 of the needle valve to prevent clogging. Cause an unscheduled speed drop.

An object of the present invention is to provide an air cylinder control device which solves the above-mentioned problems.

[0015]

According to a first aspect of the present invention, there is provided an air cylinder provided with outflow / inlet ports near both ends, a slidable piston for partitioning a cylinder chamber of the air cylinder, and an air cylinder mounted on the piston. A penetrating rod, a pump for supplying compressed air, a switching valve connected to the pump and capable of switching to one of the outflow ports at both ends, and air passing between the switching valve and the outflow ports at both ends. Two air flow stabilizing devices provided with an elongated through-hole having a small flow path area for restricting the flow rate of air and a length for stabilizing the flow rate by absorbing the pressure change of the passing air by the side resistance; An air cylinder having two check valves arranged in parallel to two air flow stabilizing devices, each having a flow path on the outflow / inlet side and opening the flow path on the switching valve side. The present invention relates to control apparatus.

According to a second aspect of the present invention, there is provided an air cylinder provided with outflow / inlet ports near both ends, a slidable piston for partitioning a cylinder chamber of the air cylinder, a rod mounted on the piston and penetrating the air cylinder, A pump for supplying air, a switching valve connected to the pump and capable of switching to one of the outlets at both ends, and a fine valve disposed between the switching valve and the outlet at both ends to restrict the flow rate of passing air. Two air flow stabilizing devices provided with a porous member having a length for stabilizing the flow by absorbing the pressure change of the air passing therethrough with the airflow resistance; And two check valves that open a flow path on the outflow / inlet side and close the flow path on the switching valve side.

According to a third aspect of the present invention, there is provided an air cylinder control method using the above-described air cylinder control device, wherein compressed air is supplied from a pump, and the compressed air is switched by a switching valve and supplied to one side. The check valve on the air side opens the flow path, sends air from the outlet on the air supply side to the cylinder chamber on the air supply side, and pushes and slides the piston with the pressure of the air in the cylinder chamber on the air supply side. Pressurizes the air in the exhaust-side cylinder chamber, exhausts the air in the exhaust-side cylinder chamber from the exhaust-side inlet / outlet, the exhaust-side check valve closes the flow path, and the exhaust-side air flow stabilizing device passes The air flow in the cylinder chamber on the air-supply side and the air in the cylinder chamber on the exhaust side are both pressurized to reduce the pressure balance while restricting the flow rate of the flowing air and absorbing the pressure change of the passing air to stabilize the flow rate and exhausting the air. Air flow on the exhaust side It relates the air cylinder control method characterized by sliding the piston while compensating the pressure of the pressure reduction amount from the device from the air side to the exhaust side.

The above-described present invention has the following operation.

One of the functions is the pressure characteristic between the front and rear cylinder chambers partitioned by the piston of the air cylinder controlled on the outlet side (see FIGS. 1, 3, 4, and 6). Since the flow rate on the outlet side (exhaust side) is controlled, the pressure in the cylinder chamber on the outlet side and the pressure in the cylinder chamber on the inlet side (air supply side) are both higher than the outside pressure and are balanced. The piston moves toward the exhaust side in a state where the reduced pressure exhausted from the air flow stabilizing device on the exhaust side is supplemented by the pressurization on the air supply side. Because the pressure balance between the front and rear cylinder chambers is always maintained,
The piston can slide with a stable and constant force. This is because the pressure of the air pushing the piston on the air supply side and the function of pulling the piston for the reduced pressure on the exhaust side work while maintaining the balance. Therefore, knocking does not occur. In addition, since the pressure in the cylinder chambers before and after the piston is already balanced when the pressure is higher than the outside air pressure, there is enough room for the air pressure to be further compressed and increased to a high pressure, or conversely expanded to a low pressure by changing the load on the piston. Since there is no air volume change, the volume change of the air due to the load change hardly occurs. Therefore, since the speed of the piston and the rod is hardly affected by the load change, the movement of the piston can be completely controlled.

The second effect is that the shape of the portion which restricts the flow rate of the air passing through the air flow stabilizing device has a function of stably passing a constant flow rate. In the case of the elongated through-hole, the air flows in from the inlet having a small flow area and flows out from the outlet having the same small flow area, so that the air does not expand and contract or the amplitude of the outflow does not occur (see FIG. 2). . In the case of the porous material, the air flows in through the fine holes and flows out of the fine holes, so that the air does not expand or contract and the outflow does not have an amplitude (see FIG. 5). Both have a structure in which a certain amount of air can pass stably, and the air passes and flows out with a smooth feeling. Therefore, the speed of the piston is constant and knocking does not occur.

The third effect is that since the distance over which the flow rate of the air flow rate stabilizing device can be controlled is long, resistance is applied to the passing air to absorb a pressure change of the air and stabilize the flow rate.
In the case of an elongated through-hole, the flow rate of the passing air is restricted by the small flow passage area, and the flow rate is stabilized by absorbing the pressure change of the passing air by the side resistance by giving it a certain length (Fig. 2). In the case of a porous member, the flow rate of the passing air is restricted by the fine holes, and the flow rate is stabilized by absorbing the pressure change of the passing air by the flow resistance by providing a certain length (see FIG. 5). . Because the distance over which the air flow can be controlled is long, the pressure change wave before flowing into the air flow stabilizer also flattens as the air passes through the air flow stabilizer, and the air that flows out of the air flow stabilizer Is stabilized at a constant flow rate. Therefore, knocking does not occur. Further, the outflow amount of the air is not affected by the pressure change of the air. Therefore,
Even if a load change occurs in the piston and the rod, since the flow rate of the air flow stabilizing device on the exhaust side is constant and stable, the speed of the piston and the rod does not change.

In the fourth function, since the shape of the ventilation portion of the air flow stabilizing device is not a gap between the surfaces, the structure has a structure in which the debris is hardly caught, so that the debris is hardly clogged. In the case of an elongated through-hole, debris smaller than the entrance passed through without being caught on the way and were discharged, and debris larger than the entrance were temporarily stopped outside the entrance, and the air supply side and the exhaust side were reversed by the switching valve. Sometimes, even when the check valve opens the flow path, a small amount of air passes through the air flow stabilizer (see FIG. 2). In the case of a porous member, since many fine holes are formed on the surface into which air flows, even if dust enters one fine hole, there is no effect on the air permeability of the other many fine holes. Most of the debris is cleaned when the air supply side and the exhaust side are reversed by the valve (a small amount of air passes through the air flow stabilizer even when the check valve opens the flow path, see FIG. 5). In both cases, clogging is unlikely to occur and debris is easily removed. Therefore, a sudden speed drop does not occur.

By the above four operations, low-speed operation can be performed at a constant speed without knocking, and operation can be performed at a constant speed even if there is a change in load on the piston and the rod. No effect is achieved.

The above-mentioned air cylinder control device is economical because of its low production cost. In addition, there is no problem such as oil odor or oil leakage during use.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the accompanying drawings, but it is needless to say that the present invention is not limited to the following embodiments.

FIG. 2 shows an air flow stabilizing device 1 provided with an elongated through hole 8. The outer diameter of the air flow stabilizing device 1 is equal to or larger than the inner diameter of the connecting pipe 11, and the inner diameter (flow passage area) of the elongated through hole 8 is smaller than the inner diameter of the connecting pipe 11. The air flowing from the connecting pipe 11 into the elongated through hole 8 of the air flow stabilizing device 1 and flowing out of the connecting pipe 11 flows as indicated by an arrow in the drawing. The flow rate of the air passing through the elongated through hole 8 is restricted, the flow rate change is stabilized, and the pressure change is flattened. If necessary, a filter having a mesh smaller than the inner diameter of the elongated through hole 8 may be provided before and after the air flow stabilizing device 1.

FIG. 1 shows an embodiment of an air cylinder controller using an air flow stabilizing device 1 provided with an elongated through hole 8. The air cylinder 3 includes an air cylinder 3 provided with outflow / inlet ports 2 near both ends, a slidable piston 5 for partitioning a cylinder chamber 4 of the air cylinder 3, and a rod mounted on the piston 5 and penetrating the air cylinder 3. 6. Compressed air is supplied from a pump (not shown) to a switching valve 7 connected to the pump. Switching valve 7
Is connected to one outlet and the outlet 2 at one end. The other outlet of the switching valve 7 is connected to the outlet 2 at the other end. The switching valve 7 switches the supply of air to the outlet 2 at both ends. The connection pipe 11 on the opposite side of the air supply from the switching valve 7 is released to the outside air. Two air flow stabilizing devices 1 each having an elongated through hole 8 are arranged in the middle of a connecting pipe 11 connecting the switching valve 7 and the outflow / inlet ports 2 at both ends. The elongated through-hole 8 has a small flow passage area for limiting the flow rate of the passing air, and a length for stabilizing the flow rate by absorbing a pressure change of the passing air by the side resistance. A check pipe 9 that connects the front and rear of each of the two air flow stabilizing devices 1 with a connecting pipe 11 and opens a flow path on the outflow inlet 2 side and closes the flow path on the switching valve 7 side in parallel with the air flow stabilizing apparatus 1. Is arranged. FIG. 1A shows a state in which the rod 6 starts to extend,
1B shows a state immediately before the rod 6 is fully extended, FIG. 1C shows a state where the rod 6 starts to contract, and FIG. 1D shows a state immediately before the rod 6 is completely contracted. With the outlet side control, the piston 5
Are filled with the same pressure of compressed air (short arrow), and the reduced pressure discharged from the air flow stabilizing device 1 on the outflow side is reduced by the supply of compressed air from the inflow side. The piston 5 is moved to the outflow side while supplementing.

FIG. 3 shows an embodiment of an air cylinder control device using the air flow stabilizing device 1 provided with the elongated through holes 8. Although the basic structure is the same as that of the air cylinder control device of FIG. 1 described above, a throttle valve 12 with a check valve 9 is provided in the middle of a connecting pipe 11 connecting the switching valve 7 and the air flow stabilizing device 1. And a solenoid valve 13 in the middle of a connecting pipe 11 connecting the air flow stabilizing device 1 on the head side and the outlet 2 side.
And an exhaust pipe 15 provided with a relief valve 14 is different. The throttle valve 12 can restrict the exhaust to a flow rate of the air flow stabilizing device 1 or less. The exhaust pipe 15 is for increasing the speed of the piston 5 moving to the head side to be equal to the speed of the piston 5 moving to the rod side. Piston area x pressure = torque, but piston area on the rod side = piston area-rod area.
Since the pushing force to the head side is weak, the pressure is compensated by the reduced pressure due to the exhaust from the exhaust pipe 15.

FIG. 5 shows an air flow stabilizing device 1 provided with a porous body 10. The inside of the pipe-shaped air flow stabilizing device 1 is occupied by a porous material 10 having air permeability. From the connecting pipe 11 to the porous material 1 of the air flow stabilizing device 1
The air flowing into the connection pipe 11 and flowing out of the connection pipe 11 flows as indicated by arrows in the drawing. The flow rate of the air passing through the porous member 10 is restricted, the flow rate change is stabilized, and the pressure change is flattened. If necessary, a filter having a mesh smaller than the fine holes of the porous body 10 may be provided before and after the air flow stabilizing device 1.

FIG. 4 shows an embodiment of an air cylinder control device using the air flow stabilizing device 1 provided with the porous material 10. The air cylinder 3 includes an air cylinder 3 provided with outflow / inlet ports 2 near both ends, and a slidable piston 5 partitioning a cylinder chamber 4 of the air cylinder 3.
And a rod 6 attached to the piston 5 and penetrating through the air cylinder 3. Compressed air is supplied from a pump (not shown) to a switching valve 7 connected to the pump. One outlet of the switching valve 7 is connected to the outlet 2 at one end. The other outlet of the switching valve 7 is connected to the outlet 2 at the other end. The switching valve 7 switches the supply of air to the outlet 2 at both ends. The connection pipe 11 on the opposite side of the air supply from the switching valve 7 is released to the outside air. In the middle of a connecting pipe 11 connecting the switching valve 7 and the outflow / inlet 2 at both ends, a porous 10 is provided.
Two air flow stabilizers 1 are provided. Porous 10
Has a fine hole for limiting the flow rate of passing air and a length for stabilizing the flow rate by absorbing a pressure change of the passing air by a ventilation resistance. A check pipe 9 that connects the front and rear of each of the two air flow stabilizing devices 1 with a connecting pipe 11 and opens a flow path on the outflow inlet 2 side and closes the flow path on the switching valve 7 side in parallel with the air flow stabilizing apparatus 1. Is arranged. FIG.
4A shows a state in which the rod 6 starts to expand, FIG. 4B shows a state just before the rod 6 extends, FIG. 4C shows a state in which the rod 6 starts to contract, and FIG. 4D shows a state in which the rod 6 contracts. It is on the verge. In the outlet side control, the cylinder chambers 4 on both sides partitioned by the piston 5 are filled with compressed air of the same pressure (short arrow), and the reduced pressure discharged from the air flow stabilizing device 1 on the outlet side is reduced from the inlet side. The piston 5 is moved to the outflow side while supplementing with the compressed air supply.

FIG. 6 shows an embodiment of an air cylinder control device using the air flow stabilizing device 1 provided with the porous material 10. The basic structure is the same as that of the air cylinder control device of FIG. 4 described above, except that a throttle valve 12 with a check valve 9 is provided in the middle of a connecting pipe 11 connecting the switching valve 7 and the air flow stabilizing device 1. The difference is that an exhaust pipe 15 provided with a solenoid valve 13 and a relief valve 14 is disposed in the middle of a connecting pipe 11 connecting the air flow stabilizing device 1 on the head side and the outflow / inlet 2 side. The throttle valve 12 can restrict the exhaust to a flow rate of the air flow stabilizing device 1 or less. The exhaust pipe 15 is for increasing the speed of the piston 5 moving to the head side to be equal to the speed of the piston 5 moving to the rod side. Piston area x pressure = torque, but piston area on the rod side = piston area-rod area.
Since the pushing force to the head side is weak, the pressure is compensated by the reduced pressure due to the exhaust from the exhaust pipe 15.

In each of the above embodiments, when the inner diameter of the tube of the air cylinder 3 is 40 mm, the inner diameter of the elongated through hole 8 is 0.5 mm and the length is 10 mm, and the fine hole of the porous 10 is several microns and the length is 10 mm. Was used. When the apparatus was operated at a low speed, no knocking occurred. A load change of -15% to + 100% was applied during the process from the start of the extension of the rod 6 to the end of the extension of the rod 6, but no change in speed and no knocking occurred.

[0033]

According to the air cylinder control device according to the present invention described above, the following effects can be obtained.

Since the flow rate on the outlet side (exhaust side) is controlled, the pressures in the cylinder chamber on the outlet side and the cylinder chamber on the inlet side (air supply side) are both higher than the outside pressure and are balanced. The piston moves toward the exhaust side in a state where the reduced pressure exhausted from the air flow stabilizing device on the exhaust side is supplemented by the pressurization on the air supply side. Since the pressure balance between the front and rear cylinder chambers is always maintained, the piston can be slid with a stable and constant force. This is because the pressure of the air pushing the piston on the air supply side and the function of pulling the piston for the reduced pressure on the exhaust side work while maintaining the balance. Therefore,
No knocking occurs. In addition, since the pressure in the cylinder chambers before and after the piston is already balanced when the pressure is higher than the outside air pressure, there is enough room for the air pressure to be further compressed and increased to a high pressure, or conversely expanded to a low pressure by changing the load on the piston. Since there is no air volume change, the volume change of the air due to the load change hardly occurs. Therefore, since the speed of the piston and rod is hardly affected by the load change,
The movement of the piston can be completely controlled.

The shape of the part that restricts the flow rate of the air passing through the air flow stabilizing device has a function of stably passing a constant flow rate. In the case of the elongated through-hole, the air flows in from the inlet having a small flow area and flows out from the outlet having the same small flow area, so that the air does not expand or contract and the outflow amount does not have an amplitude. In the case of using a porous material, the air flows in through the fine holes and flows out of the fine holes, so that the air does not expand or contract and the outflow does not have an amplitude. Both have a structure in which a certain amount of air can pass stably, and the air passes and flows out with a smooth feeling. Therefore, the speed of the piston is constant and knocking does not occur.

Since the distance over which the flow rate of the air flow rate stabilizing device can be controlled is long, side resistance is applied to the passing air to absorb a pressure change of the air and stabilize the flow rate. In the case where the elongated through-hole is provided, the flow rate of the passing air is restricted by a small flow passage area, and the flow rate is stabilized by absorbing the pressure change of the passing air by the side resistance by having a certain length. In the case of a porous member, the flow rate of the passing air is restricted by the fine holes, and the flow rate is stabilized by absorbing the pressure change of the passing air by the ventilation resistance by having a certain length. Because the distance over which the air flow can be controlled is long, the pressure change wave before flowing into the air flow stabilizer also flattens as the air passes through the air flow stabilizer, and the air that flows out of the air flow stabilizer Is stabilized at a constant flow rate. Therefore, knocking does not occur. Further, the outflow amount of the air is not affected by the pressure change of the air. Therefore, even if a load change occurs in the piston and the rod, the flow rate of the air flow stabilizing device on the exhaust side is constant and stable, so that the speed of the piston and the rod does not change.

Since the shape of the ventilation portion of the air flow stabilizing device is not a gap between the surfaces, the structure is such that the dust is not easily caught, so that clogging with the dust is less likely to occur. In the case of an elongated through-hole, debris smaller than the entrance passed through without being caught on the way and were discharged, and debris larger than the entrance were temporarily stopped outside the entrance, and the air supply side and the exhaust side were reversed by the switching valve. Sometimes cleaned. In the case of a porous member, since many fine holes are formed on the surface into which air flows, even if dust enters one fine hole, there is no effect on the air permeability of the other many fine holes. Most debris is cleaned when the inlet and exhaust sides are reversed by the valve. In both cases, clogging is unlikely to occur and debris is easily removed. Therefore, a sudden speed drop does not occur.

As described above, low-speed operation can be performed at a constant speed without knocking, and operation can be performed at a constant speed even when there is a load change on the piston and the rod.
There are three effects that the speed does not suddenly decrease due to clogging.

The air cylinder control device is economical because of low production cost. In addition, there is no problem such as oil odor or oil leakage during use.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of an air cylinder control device, in which (A) shows a state in which a rod starts to extend,
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 2 is a sectional view of an air flow stabilizing device provided with an elongated through hole.

FIG. 3 is an explanatory diagram showing an embodiment of an air cylinder control device.

4A and 4B are explanatory views showing an embodiment of an air cylinder control device, in which FIG.
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 5 is a sectional view of an air flow stabilizing device provided with a porous body.

FIG. 6 is an explanatory diagram showing an embodiment of an air cylinder control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air flow stabilizer 2 Outflow inlet 3 Air cylinder 4 Cylinder chamber 5 Piston 6 Rod 7 Switching valve 8 Slender through hole 9 Check valve 10 Porous

[Procedure amendment]

[Submission date] June 3, 1999 (1999.6.3)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of an air cylinder control device, in which (A) shows a state in which a rod starts to extend,
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 2 is a sectional view of an air flow stabilizing device provided with an elongated through hole.

FIG. 3 is an explanatory diagram showing an embodiment of an air cylinder control device.

4A and 4B are explanatory views showing an embodiment of an air cylinder control device, in which FIG.
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 5 is a sectional view of an air flow stabilizing device provided with a porous body.

FIG. 6 is an explanatory diagram showing an embodiment of an air cylinder control device.

FIG. 7 is a cross-sectional view of a needle valve used in a conventional air cylinder control device. ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 6, 1999 (1999.8.6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an embodiment of an air cylinder control device, in which (A) shows a state in which a rod starts to extend,
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 2 is a sectional view of an air flow stabilizing device provided with an elongated through hole.

FIG. 3 is an explanatory diagram showing an embodiment of an air cylinder control device.

4A and 4B are explanatory views showing an embodiment of an air cylinder control device, in which FIG.
(B) shows a state just before the rod is fully extended, (C) shows a state where the rod starts to contract, and (D) shows a state just before the rod is completely contracted.

FIG. 5 is a sectional view of an air flow stabilizing device provided with a porous body.

FIG. 6 is an explanatory diagram showing an embodiment of an air cylinder control device.

FIG. 7 is a cross-sectional view of a needle valve used in a conventional air cylinder control device.

[Description of Signs] 1 Air flow stabilizer 2 Outflow / inlet 3 Air cylinder 4 Cylinder chamber 5 Piston 6 Rod 7 Switching valve 8 Slender through hole 9 Check valve 10 Porous

Claims (3)

[Claims] An air cylinder (3) provided with an outflow / inlet (2) near each end, a slidable piston (5) partitioning a cylinder chamber (4) of the air cylinder (3), and a piston (5). ), A rod (6) penetrating the air cylinder (3), a pump for supplying compressed air, and a switching valve connected to the pump and capable of switching to one side of the outlet ports (2) at both ends. 7), a small flow passage area which is disposed between the switching valve (7) and the outlet port (2) at both ends and restricts the flow rate of the passing air, and the pressure change of the passing air is absorbed by the side resistance and the flow rate is reduced. Air flow stabilizing devices (1) provided with elongated through holes (8) having a length for stabilizing the air flow, and outflow and inlet ports respectively arranged in parallel with the two air flow stabilizing devices (1) (2)
An air cylinder control device comprising two check valves (9) that open a flow path on the side and close the flow path on the switching valve (7) side. 2. An air cylinder (3) having an outflow port (2) near each end, a slidable piston (5) partitioning a cylinder chamber (4) of the air cylinder (3), and a piston (5). ), A rod (6) penetrating the air cylinder (3), a pump for supplying compressed air, and a switching valve connected to the pump and capable of switching to one side of the outlet ports (2) at both ends. 7), a fine hole arranged between the switching valve (7) and the outlet port (2) at both ends for limiting the flow rate of the passing air, and the pressure change of the passing air is absorbed by the ventilation resistance to stabilize the flow rate. Two air flow stabilizers (1) provided with a porous material (10) having a length to be changed, and an outlet (2) arranged in parallel with each of the two air flow stabilizers (1) Open the flow path on the side and the flow path on the switching valve (7) side An air cylinder control device, comprising: two check valves (9) for closing the valve. 3. An air cylinder control method using an air cylinder control device according to claim 1, wherein compressed air is supplied from a pump, and the compressed air is switched by a switching valve (7) to one side. The air supply side check valve (9) opens the flow path, and supplies air from the air supply side outlet port (2) to the air supply side cylinder chamber (4). The piston (5) is pressed and slid by the pressure of the air in the cylinder chamber (4) of the cylinder chamber (4).
And the air in the cylinder chamber (4) on the exhaust side is exhausted from the outlet (2) on the exhaust side, and the check valve (9) on the exhaust side closes the flow path, stabilizing the air flow rate on the exhaust side. Equipment (1)
Restricts the flow rate of the air passing therethrough, absorbs the pressure change of the passing air, stabilizes the flow rate, and exhausts the air. The cylinder chamber (4) on the air supply side and the cylinder chamber (4) on the exhaust side
The piston (5) is slid to the exhaust side while the pressure from the air supply side is supplemented by the reduced pressure from the air flow stabilizing device (1) on the exhaust side in a state where the air is pressurized together and the pressure is balanced. An air cylinder control method characterized by the above-mentioned.