KR20200079988A - Pneumatic actuator for valve opening and closeing - Google Patents

Abstract

The present invention relates to a pneumatic actuator for opening and closing a valve, which can open and close a valve by using pneumatic pressure. The pneumatic actuator for opening and closing a valve comprises: a cylinder body having a penetrated inner circumference to guide a straight-line motion; a piston rod inserted and installed into the inner circumference of the cylinder body to directly transfer energy to a transport object; a pair of covers installed on the left and right end surfaces of the cylinder body to have a port to supply or discharge compressed air; and a tie rod to fix the covers. According to the present invention, only one cylinder body is provided to improve an assembly property and reduce the possibility of leaking air to provide a pneumatic actuator with excellent quality. Moreover, a rack gear of a left and a right piston is connected to a pinion gear formed on a driveshaft to minimize backlash, thereby improving the response property of a valve.

Description

Pneumatic actuator for valve opening and closeing}

The present invention relates to a pneumatic actuator for opening and closing the valve, and more particularly to a pneumatic actuator for opening and closing the valve to open and close the valve using pneumatic.

Valves are widely used in industry, and various types of valves are known, and suitable ones are used depending on the purpose.

The valve for controlling the flow of fluid must be opened and closed, and can be classified into a manual, electronic, or pneumatic valve, and an actuator is provided for the electronic and pneumatic valves.

An actuator is an actuator, a mechanism used to move or control a system. In other words, it is a term that refers to a prime mover that uses electricity, hydraulic pressure, compressed air, etc., and operates as an energy source in the form of current, operating hydraulic pressure, and mechanical pressure, so that proportional control is achieved.

In addition, an actuator for opening and closing a valve using pneumatics is provided with a valve on one side of a pipe through which the fluid flows, and serves to open or block the flow of the fluid, and a valve disc for opening or blocking the fluid is formed inside the valve. And a valve drive shaft is formed on one side of the valve disc, and when the valve drive shaft is rotated, the valve disc integrally formed therewith is also rotated to open and close the fluid flow.

The actuator for opening and closing a valve using such pneumatics discloses a'butterfly valve opening and closing device using a pneumatic actuator' disclosed in Patent No. 10-0567602 to limit the rotation range of a yoke that rotates together with the valve shaft, but can adjust both open and closed. An open angle adjustment bolt and a closed angle adjustment bolt are provided to increase the precision of control.

In addition, in the'actuator for opening and closing the valve using pneumatic pressure' disclosed by Patent No. 10-1367066 by the present inventor, the left and right pistons of the cylinder are rotated using the left and right pistons, but the left and right pistons face each other. When the sliding member is attached and the left and right sliding surfaces formed on the outside of the sliding member are connected to the operation roller fixed to the front end of the eccentric operation piece of the valve drive shaft, even if the left and right sliding members repeat sliding from side to side, the valve drive shaft and the operation roll Was to maintain the same installation interval, so that the correct proportional control could be achieved by means of opening with the same nominal force.

However, in the conventional actuator for opening and closing a valve using pneumatic pressure including the above-described prior art, the valve is randomly changed in the operating state in the event of an abnormal condition due to a failure or power failure due to a failure or power failure of the electronic valve or the compressed air supply unit, which is a control means of the valve. In addition to the problem that the control state of the controller may become unstable, there is a problem in that the torque varies depending on the stroke distance of the piston, so that a uniform opening and closing action is not achieved.

As a proposed technique to solve this problem, Korean Patent Registration No. 10-1717042 "Actuator for opening and closing a valve using pneumatic pressure" has been proposed.

Actuator for opening and closing the valve using pneumatic according to the prior art, as shown in Figures 1 and 2, using the first and second pistons 25 and 26 of the first and second cylinders 21 and 22 In the actuator for opening and closing a valve using pneumatic pressure that is opened and closed by rotating the valve drive shaft (10), the first pneumatic chamber (30) primary side (31) of the first cylinder (21) is made of the second cylinder (22). 2 The pneumatic chamber 40 is provided as a pneumatic chamber having a larger volume than the primary side 41, and the primary side 31 of the first pneumatic chamber 30 is connected to the pneumatic supply unit 50 and the first pneumatic pipe 61 The first pneumatic pipe 61 is connected to the second pneumatic pipe 62 through a pneumatic detection valve 80 that senses the pressure of the electromagnetic valve 70 and the pneumatic supply unit 50, and the second pneumatic pipe 62 ) Is respectively connected to the secondary side 32 of the first pneumatic chamber 30 and the primary side 41 of the second pneumatic chamber 40, and the secondary side 42 of the second pneumatic chamber 40 is a through hole Characterized in that it consists of a structure that communicates with the atmosphere through (44).

The actuator for opening and closing the valve using pneumatics of the prior art as described above rotates the valve driving shaft using the first and second pistons of the first and second cylinders so that the valve is opened and closed while the electromagnetic valve or the pneumatic supply unit, which is the driving means of the valve, fails A pneumatic circuit that automatically shuts off the valve when an abnormal condition occurs due to power failure or power failure, so that the valve can maintain a stable operating condition, and the first side of the first pneumatic chamber of the first cylinder is the second pneumatic chamber of the second cylinder 1 It is equipped with a pneumatic chamber with a larger volume than the vehicle side, so that the air is not compressed on the primary side of the first pneumatic chamber, so that the valve can be opened and closed with a constant torque regardless of fluctuations in the piston stroke distance.

However, the above-described conventional technology has a problem in that it is difficult to manufacture because it is configured in a manner in which the left and right cylinders are divided and assembled, and there is a practical use difficulty in that high pressure air is likely to leak.

KR 10-1717042 B1

An object of the present invention to solve the problems derived from the preceding background, is to provide a pneumatic actuator for opening and closing the valve that has a relatively simple structure and has excellent response characteristics and minimizes occurrence of backlash.

Meanwhile, the object of the present invention is not limited to the above-mentioned object, and other objects not mentioned will be clearly understood from the following description.

The above object is, according to an embodiment of the present invention, a cylinder body having a pierced inner diameter to guide linear motion; A piston rod inserted into the inner diameter of the cylinder body to directly transfer energy to the conveyed object; A pair of covers installed on left and right ends of the cylinder body and having ports for supplying or exhausting compressed air; And a tie rod for fixing the cover; it can be achieved by a pneumatic actuator for opening and closing a valve.

Here, the cover is divided into a piston-side head cover and a rod-side rod cover, and is characterized in that gaskets or packings are inserted to maintain airtightness to prevent air leakage.

And when the compressed air is supplied through one of the cover ports of the pair of covers, the compressed air is discharged to the outside through the other cover port, and the piston rod moves toward the side where air is discharged to move the stroke.

According to the present invention according to the above-described embodiment, as the cylinder body is made of one, the assembly characteristics are good and it is possible to provide a pneumatic actuator of excellent quality by reducing the possibility of high-pressure air leakage.

In addition, since the rack gears of the left and right pistons are connected to the pinion gears formed on the drive shaft, the response characteristics of the valve can be improved as the occurrence of backlash can be minimized.

1 is a cross-sectional view showing the action when the valve is opened by providing the electromagnetic valve in the actuator for opening and closing the valve using pneumatic according to the prior art,
Figure 2 is a cross-sectional view showing the action when the valve is blocked by the electromagnetic valve in the actuator for opening and closing the valve using pneumatic according to the prior art,
3 is a conceptual diagram showing a pneumatic actuator for opening and closing a valve according to an embodiment of the present invention,
4 is a conceptual diagram showing an example that can be added in an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only the embodiments allow the disclosure of the present invention to be complete, and have ordinary knowledge in the art to which the present invention pertains. It is provided to completely inform the person of the scope of the invention. And the terminology used herein is for describing the embodiments, and is not intended to limit the present invention. In the present specification, the singular form includes the plural form unless otherwise specified in the phrase.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. On the other hand, the illustration and detailed description of the configuration and the action and effect thereof, which can be easily recognized by those having ordinary knowledge in the relevant technical field, will be briefly omitted or omitted, and the details related to the present invention will be described in detail.

The pneumatic actuator for opening and closing the valve according to an embodiment of the present invention, as shown in Figure 3, the cylinder body 100 having a pierced inner diameter to guide the linear motion, and the cylinder body 100 is inserted into the installation A pair of covers (320,340) having a piston rod (200) that directly transfers energy to the transported object and a port (322,342) for supplying or exhausting compressed air, installed on the left and right ends of the cylinder body (100) And a tie rod 400 for fixing the covers 320 and 340.

The pneumatic actuator for opening and closing the valve converts compressed air energy into mechanical linear kinetic energy or rotary kinetic energy, and the structure is simple and easy to implement a linear motion mechanism. Although there is no significant difference in structure or operation principle from hydraulic pressure, air has a compressibility and a small viscosity compared to hydraulic pressure, so there is a big difference from hydraulic oil and there is a detailed structural difference.

Here, the cover is divided into a piston-side head cover 320 and a rod-side rod cover 340, and gaskets or packings are inserted to maintain airtightness to prevent air leakage.

In addition, it may be composed of a cushion valve 620 that absorbs shock, a cushion packing 610 and a cushion ring 220, and a tie rod 400 and a nut 332 that secure the tube 500 and the covers 320 and 340. have.

The present invention is to obtain the driving output required by supplying compressed air therein, and supplying compressed air through one of the cover ports of the pair of covers (320,340) through the other cover port. By discharging compressed air to the outside, the piston rod 200 moves to the side where air is discharged, thereby completing the stroke movement.

Conversely, when the air supply side is exhausted and the compressed air is supplied to the exhaust side, the piston rod 200 moves in the opposite direction to complete the stroke movement, which is called reciprocating motion of the cylinder and the piston rod 200 covers the rod. The movement moving toward (340) is called forward and the movement moving toward the head covers (320,340) is called backward. Therefore, kinetic energy is generated due to the weight and speed of the load when the forward and reverse operations are performed. Since this kinetic energy causes an impact at the end of the stroke and damages the device, various cushion parts are attached.

Hereinafter, with reference to Figure 4 will be described with respect to the cushion action when the cylinder is retracted.

4 is a conceptual diagram showing an example that can be added in an embodiment of the present invention.

Referring to FIG. 4, air is exhausted through the head side cover and the port, but from the point when the cushion ring at the end of the piston rod contacts the cushion packing, the pressure in the pressure action chamber cannot be directly exhausted to the exhaust port and the cushion needle side hole is opened. Since it is exhausted only through, the exhaust flow rate is rapidly reduced.

For this reason, the amount of shock absorption can be adjusted as a needle valve, but if excessive impact is applied, the cushion packing may be damaged or other parts may be damaged.

According to the present invention described so far, as the cylinder body is made of one, there is an effect that it is possible to provide an excellent quality pneumatic actuator by reducing the possibility of leakage of high pressure air having good assembly characteristics.

In addition, since the rack gears of the left and right pistons are connected to the pinion gears formed on the drive shaft, the response characteristics of the valve can be improved as the occurrence of backlash can be minimized.

The foregoing has outlined rather broadly the features and technical advantages of the present invention in order to better understand the claims of the invention that follows. Those of ordinary skill in the art to which the present invention pertains will appreciate that the present invention may be implemented in other specific forms without changing its technical spirit or essential features. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the following claims rather than the above detailed description, and it should be interpreted that all changes or modifications derived from the claims and equivalent concepts are included in the scope of the present invention.

100: cylinder body
200: piston rod
210: piston packing
220: cushion ring
230: rod packing
240: wiper
260: bush
320: head cover
340: road cover
322, 342: port
332: nut
400: tie rod
500: tube
610: cushion packing
620: cushion valve

Claims (3)

In the pneumatic actuator for opening and closing the valve,
A cylinder body having a pierced inner diameter that guides linear motion;
A piston rod inserted into the inner diameter of the cylinder body to directly transfer energy to the conveyed object;
A pair of covers installed on left and right ends of the cylinder body and having ports for supplying or exhausting compressed air; And
A tie rod fixing the cover;
Pneumatic actuator for opening and closing the valve, characterized in that it comprises a. According to claim 1,
The cover is divided into a piston-side head cover and a rod-side rod cover,
A pneumatic actuator for valve opening and closing, characterized in that gaskets or packings are inserted to prevent air leakage to maintain airtightness. According to claim 1,
When the compressed air is supplied through one cover port of the pair of covers, the compressed air is discharged to the outside through the other cover port, and the piston rod moves to the side where the air is discharged, thereby opening and closing the valve. For pneumatic actuators.

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