JP3738431B2 - Spring return type actuator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spring return type actuator, and more particularly to an actuator that does not require a receiver tank for a conventional air source connected to a cylinder chamber via a receiver tank.
[0002]
[Prior art]
A conventional spring return type actuator will be described with reference to FIG.
In FIG. 3, 1 is a cylinder chamber, which has a piston 2 and a piston rod 3 joined to the piston 2, and has a compressed air supply / exhaust port 4. A spring chamber 5 includes a spring 6 and a spring retainer 7. 8 is a conversion unit between linear motion and rotational motion, which comprises a pin 9 on the piston rod 3 and an arm 10 engaged with the pin 9, and rotates the output shaft 11 by the linear motion of the piston rod 3, A valve or the like engaged with the output shaft 11 is driven.
[0003]
In the cylinder chamber 1, an air source 12 is connected to a compressed air supply / exhaust port 4 via a check valve 18 and a receiver tank 19 and an electromagnetic valve 20. When compressed air is supplied to the cylinder chamber 1, the output shaft 11 is rotated by the pin 9 and the arm 10 from the piston 2 through the piston rod 3. When returning, the compressed air is extracted, and the piston 2 is returned to the original position by the pressure of the spring 6.
[0004]
[Problems to be solved by the invention]
When the air source 12 is cut off due to a power failure or the like with the above configuration, compressed air from the receiver tank 19 is used because compressed air from the air source 12 cannot be obtained. FIG. 3 shows a case where the receiver tank 19 is used. However, the provision of the receiver tank 19 has a problem in that the equipment cost increases and a place for installation is required.
[0005]
It is an object of the present invention to provide an actuator that does not require the receiver tank as described above.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is an actuator having a cylinder chamber and a spring chamber, in which compressed air is injected or discharged into the cylinder chamber to move the piston and the piston rod back and forth. In a spring return type actuator that rotates the output shaft by reciprocating the piston rod that compresses or extends the spring, an air source is connected to the spring chamber, and this spring chamber is connected to the cylinder chamber via an electromagnetic valve or a manual valve. It is a spring return type actuator that is connected and uses the spring chamber or the spring chamber and the body chamber as an air tank.
[0007]
(Function)
In the present invention, an air source is connected to the spring chamber, and this spring chamber is connected to the cylinder chamber via an electromagnetic valve or a manual valve, and the spring chamber or the spring chamber and the body chamber are used as an air tank. The receiver tank is unnecessary. The spring chamber is only a spring and a spring retainer, and can sufficiently hold compressed air. In addition to this spring chamber, if a body chamber including a piston rod or a linear motion / rotation motion converter is used, a considerable amount of compressed air can be retained. Since the piston and the piston rod are sealed by an O-ring, there is no leakage of compressed air.
[0008]
The required pressure can be set by the booster valve from the operating pressure of the actuator, the volume of the space, the number of operations, etc., and smooth operation can be performed.
Further, when the air source is cut off due to a power failure or the like, the air can be operated by the air retained in the spring chamber or the spring chamber and the body chamber.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The spring return type actuator of the present invention normally injects compressed air into the cylinder chamber and moves the piston and the piston rod forward, compresses the spring in the spring chamber via the spring retainer, and discharges the compressed air at the time of return. The piston rod is moved back by the spring force of the spring to drive the output shaft.
[0010]
【Example】
FIG. 1 is a side sectional view of a spring return type actuator of the present invention, and shows a case where a cylinder is returned by the spring force of a spring. FIG. 2 shows a state in which the piston is driven using compressed air in the spring chamber and the body chamber.
1 is a cylinder chamber, 2 is a piston. 3 is a piston rod, and 4 is an air supply / exhaust port. A spring chamber 5 is loaded with a spring 6. 7 is a spring retainer. 8 is a conversion unit between linear motion and rotational motion, which comprises a pin 9 on the piston rod 3 and an arm 10 engaged with the pin 9, and rotates the output shaft 11 by the linear motion of the piston rod 3, A valve or the like engaged with the output shaft 11 is driven. The linear motion / rotational motion conversion portion 8 is a body chamber between the cylinder chamber 1 and the spring chamber 5.
[0011]
12 is an air source, 13 is a pressure increasing valve, and 14 is a pressure reducing valve. The required pressure can be set from the operating pressure of the actuator, the volume of the space, the number of operations, and the like. In some cases, the pressure increasing valve 13 and the pressure reducing valve 14 are not used.
FIG. 2 shows a state in which compressed air is supplied to the cylinder chamber by the electromagnetic valve 15 or the manual valve 16 using the air in the spring chamber and the body chamber. Therefore, it can be driven even when there is no supply of compressed air from the air source during a power failure or the like. Reference numeral 17 denotes an O-ring that seals between the piston 2 and the piston rod 3, and complete sealing is possible even when compressed air is held in the spring chamber or the spring chamber and the body chamber.
[0012]
【The invention's effect】
In the present invention, the compressed air from the air source can be held in the spring chamber and the body chamber, and the necessary pressure can be adjusted and sent to the cylinder chamber from the operating pressure of the actuator, the volume of the space, the number of operations, etc. Smooth operation is possible. In addition, even if the air from the air source is cut off due to a power failure, etc., air can be supplied to the cylinder chamber via the solenoid valve or manual valve using the air stored in the spring chamber or body chamber. There was no need to install a receiver tank, the piping system was simplified, and a compact spring return type actuator could be provided.
[Brief description of the drawings]
FIG. 1 is a side sectional view and a path diagram of a spring return type actuator according to the present invention. FIG. 2 is a side sectional view showing driving of the actuator. FIG. 3 is a side sectional view and a path diagram showing a conventional actuator. Explanation of]
1 Cylinder chamber 2 Piston 3 Piston rod 4 Air supply / exhaust port 5 Spring chamber 6 Spring 7 Spring retainer 12 Air source 15 Solenoid valve 16 Manual valve

Claims (1)

A reciprocating motion of a piston rod which is an actuator having a cylinder chamber and a spring chamber, and compresses or extends a spring of the spring chamber in accordance with the forward and backward movement of the piston and the piston rod by injecting or discharging compressed air into the cylinder chamber In the spring return type actuator that rotates the output shaft by
A spring characterized by connecting an air source to a spring chamber and connecting the spring chamber to a cylinder chamber via a solenoid valve or a manual valve, and using the spring chamber or the spring chamber and the body chamber as an air tank. Resettable actuator.

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