JPH08200206A - Spring type actuator - Google Patents

Abstract

PURPOSE: To prevent a spring used for a spring type actuator from contacting with a spring protection cylinder by its tare weight and thereby causing abrasion and damage to the spring and the spring protection cylinder. CONSTITUTION: A spring type actuator is composed by having a protection means guide shaft 11 provided on the extension line of a coaxial rod 3 and a holding means 12 provided inside an actuator spring protection cylinder 10 connected together inside the spring protection cylinder 10 and equipped with two springs 14 having one of its ends fitted to a spring bearing 4 provided on the end of the rod 3 and the other end fitted to the end part 13 of the spring protection cylinder 10 and also with a bearing 15 provided on the inner circumference of the holding means 12, while the bearing 15 is supportingly arranged slidably on the holding means guide shaft 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring type actuator which requires axial rotation such as opening and closing of a valve.

[0002]

2. Description of the Related Art A conventional spring type actuator will be described with reference to FIG. FIG. 4 is a sectional view showing the entire actuator. Reference numeral 19 is a cylinder chamber, and 20 is a piston. 21 is a rod, one end of which is fixed to the piston 20,
The other end is fixed to the spring tray 22 and is supported by the rod bearing 23. 24 is a pin, which is provided on the rod 21. Reference numeral 25 is an output shaft for opening and closing the valve, which is an arm 2
6, the sliding groove 27 of the arm 26 is engaged with the pin 24 to convert the reciprocating motion of the piston 20 into the rotary motion of the output shaft 25.

Reference numeral 28 is a spring protection cylinder. 29 is a spring,
One end is attached to a spring tray provided at the end of the rod 21, and the other end is attached to the end of the spring protection cylinder. In the conventional spring type actuator having these configurations, the spring 29
When a long one is used, the spring sags due to the weight of the spring itself and the middle part of the spring goes down, and the spring and the spring protection cylinder may come into contact with each other near the point indicated by C in the figure.

Further, a spring having a certain length or longer could not be manufactured due to the limitation of the material size and the limitation of the heat treatment equipment. Therefore, the spring was divided into a plurality of pieces and the springs were joined together.
Also in this case, similarly to the above, the spring may sag due to the weight of the spring itself, and the intermediate portion of the spring may descend, causing the spring and the spring protection cylinder to come into contact with each other.

[0005]

Therefore, since the spring sags and deforms into an arc, the repulsive force of the spring is not perpendicular to the rod, and the repulsive force of the spring cannot be effectively used. . Further, since the spring comes into contact with the spring protection cylinder, the spring and the spring protection cylinder are worn and damaged each time the actuator is operated to open or close the valve.

Further, in order to prevent the sound from being generated by the contact of the spring with the spring protection cylinder, increasing the size of the spring protection cylinder and increasing the gap between the spring and the spring protection cylinder increases the cost and is uneconomical. There was a problem that it was a target. Therefore, according to the present invention, a guide shaft for a holder is provided at the tip of the rod of the actuator, the spring is connected by the spring holder, and the sliding resistance is reduced by the bearing, so that the spring and the spring protection cylinder are not worn and are safe and secure. It is intended to provide a pneumatic actuator.

[0007]

In order to achieve the above object, the present invention provides a holder guide shaft provided on an extension line coaxial with a rod in a spring protection cylinder of an actuator, and in the spring protection cylinder. Bearings provided on the inner circumference of the holder, the two springs being connected by a holder, one end of which is attached to a spring tray provided at the end of the rod and the other end of which is attached to the end of the spring protection cylinder. A spring-type actuator in which the bearing is slidably disposed and supported on the holder guide shaft.

[0008]

With the holder provided in the spring protection cylinder, the springs are connected, one end of the spring is mounted on the spring tray provided on the end of the rod, and the other end is mounted on the end of the spring protection cylinder, and the holding is performed. Since the bearing provided on the inner circumference of the tool can slide on the holder guide shaft, the movement of the spring can be smoothed and the spring can be supported horizontally by the holder, so that the repulsive force of the spring can be reduced. You can make good use of it.

[0009]

1 is a side sectional view showing a spring type actuator of the present invention. FIG. 2 is an enlarged cross-sectional view of the holder of the spring type actuator of the present invention. In FIG. 1, 1 is a cylinder chamber and 2 is a piston. 3 is a rod, one end of which is fixed to the piston 2 and the other end of which is a spring tray 4
And is supported by a rod bearing 5. 6
Is a pin attached to the rod 3. Reference numeral 7 is an output shaft for rotating the shaft such as opening and closing the valve, and has an arm 8.
The sliding groove 9 is engaged with the pin 6 and converts the reciprocating movement of the piston 2 into the rotational movement of the output shaft 7.

Reference numeral 10 is a spring protection cylinder. A guide shaft 11 for a holder is attached to the tip of the rod 3. A holding tool 12 holds and connects a spring. 13 is the end of the spring protection tube. Reference numeral 14 is a spring, which is connected by a holder 12 and has one end attached to a spring tray 4 provided at the end of the rod and the other end attached to an end 13 of a spring protection cylinder. This spring 14 serves to push the piston 2 back.

As shown in FIG. 2, the spring 14 has points A and B.
The points are connected via a holder 12. Reference numeral 15 denotes a bearing, which is provided on the inner circumference of the holder 12 and is provided with the holder guide shaft 1.
It has a low resistance and can slide smoothly. Therefore, the holder 12 is held in a balanced state by the lengths of the two springs 14 connected by the holder 12.

Further, since the bearing 15 can slide on the holder guide shaft 11 with a small resistance, the spring 14 does not sag and come into contact with the spring protection cylinder.
Since the repulsive force of can be effectively transmitted to the rod 3,
It is effective for pushing back the piston 2. FIG. 3 shows another embodiment of the present invention. Reference numeral 16 is a holder guide shaft, 17 is a holder, and 18 is a bearing.

In the actuator shown in the other embodiment, the holder guide shaft is thinner than that shown in the embodiment of the present invention. The operation and action are similar to those of the actuator shown in the embodiment of the present invention.

[0014]

In the spring type actuator, since the bearing is provided on the inner circumference of the spring holder, the holder can be smoothly slid on the holder guide shaft and the flexure due to the weight of the spring can be eliminated. You can now effectively use the repulsive force of. Moreover, since the holder guide shaft is fixed to the rod, an accurate and reliable actuator can be provided.

[Brief description of drawings]

FIG. 1 is a side sectional view of an actuator showing an embodiment of the present invention.

FIG. 2 is a partially enlarged side sectional view of a spring holding portion according to an embodiment of the present invention.

FIG. 3 is a side sectional view of an actuator showing another embodiment of the present invention.

FIG. 4 is a side sectional view of an actuator according to a conventional invention.

[Explanation of symbols]

 3 Rod 4 Spring Dish 10 Spring Protective Cylinder 11, 16 Holder Guide Shaft 12, 17 Clamp 13 End of Spring Protective Cylinder 14 Spring 15, 18 Bearing

Claims (1)

[Claims] 1. A holder protection shaft provided on an extension line coaxial with a rod in a spring protection cylinder of an actuator is connected to a holder provided in the spring protection cylinder, and one end thereof is connected to an end portion of the rod. And a bearing provided on the inner circumference of the holder, the bearing being on the holder guide shaft. A spring-type actuator characterized in that it is slidably disposed and supported by.