KR101324802B1 - A limit switch for valve - Google Patents

Abstract

The present invention relates to a limit switch for a valve, comprising: an operating shaft installed to penetrate inside a case installed on an upper portion of an actuator for operating a stem connected to a valve of the valve; and an operating shaft protruding upward of the case. In the limit switch for valves comprising an indicator for visually confirming the opening and closing state of the valve, the operating shaft located in the case and the operating unit installed inside the case to apply the opening and closing of the valve to the controller as an electrical signal. ;
The operation unit is installed in the intermediate position of the operating shaft in contact with the open terminal and the closing terminal of the switch installed on one side of the case to install the opening rod and the closing rod to apply an electrical signal to the controller of the control room to open and close the valve, The opening rod and the closing rod are screwed into the opening hole and the closing hole to be formed through the opening in a direction perpendicular to the axial center of the operating shaft, and the ends of the opening and closing rod in contact with the opening and closing terminals A tip is provided, and an adjustment head is formed at the rear end of the opening and closing rods to close and move the opening and closing rods in the direction of the opening and closing terminals, so that the opening and closing state of the valve can be accurately applied to the indicator and the controller. Of course, it has a feature that can simplify the structure of the limit switch.

Description

Limit switch for valves {A LIMIT SWITCH FOR VALVE}

The present invention relates to a limit switch for a valve, and more particularly, an improved limit applied to a valve to visually inform a state of opening or closing of a valve while applying an electrical signal to a controller to check and process the improved limit. The provision of a switch.

Valves used for controlling the flow of fluid have been developed and used in a variety of types, such as the valve is the flow of fluid by the forward and reverse rotation operation of the stem connected to the disk coupled to the flow path formed in the valve body This configuration is to control.

The stem applied to the valve is mechanically controlled using an actuator for accurate control and smooth operation. The actuator is equipped with a limit switch to open and close the valve in the control room while visually checking the open / closed state of the valve in the field. Open / close information is applied to the controller to recognize the state.

Looking at the technical configuration of the limit switch as described above with reference to FIG.

The conventional valve limit switch 1 is installed to penetrate the operating shaft 3 connected to the stem of the actuator or the valve inside the case 2 installed on the upper part of the actuator.

The operating shaft 3 protruding upward of the case 2 is provided with an indicator 4 for visually confirming the opening and closing state of the valve, and the operating shaft 3 and the case (located inside the case 2). 2) Inside the operating unit 5 for applying the opening and closing of the valve to the controller as an electrical signal is installed.

The actuating part 5 is located at an intermediate position of the actuating shaft 3 so that the actuating part 5 can be operated in contact with the opening terminal 7 and the closing terminal 8 of the switch 6 installed at one inner side of the case 2. When the disc of the valve is in the open position by combining the open cam 9 and the close cam 10 at the same position as the open and close terminals 7 and 8, the open cam 9 is in contact with the open terminal 7. When the disc is in the closed position, the closing cam 10 contacts the closing terminal 8 to apply an electrical signal to the controller.

The opening and closing cams 9 and 10 are fixed to the operating shaft 3 on which the adjustment cam 12 having the fine concavo-convex protrusions 11 formed on the outer surface thereof, and the opening and closing cams 9 and 10. In the inner diameter surface of the) uneven protrusions 12 are formed to be engaged with each other.

A spring 13 is installed between the open and closed cams 9 and 10 to keep the open and closed cams 9 and 10 in the engaged position at all times, and the open and close cams 9 and 10 are adjusted. After moving to the up and down direction to move out of the adjustment rim 12, determine the direction and then re-engage, and the stopper so as not to leave the adjustment rim 12 by the spring 13 to the open and closed cams (9,10). It is formed by forming.

In the prior art as described above, since the uneven protrusions formed on the adjustment rim fixed to the working shaft and the uneven protrusions formed on the opening and closing cams are formed in a size of about 4 °, they are applied to a valve having a diameter of about 200 mm. When the uneven projection is a form having a gap of about 6mm.

Therefore, no matter how precisely the error is adjusted, the indicator shows that the valve is normally open and closed, and even though the controller receives an electric signal through the switch, the actual valve disk is formed on the valve body. It becomes a form which keeps a state which has a flow path hole and a predetermined gap.

Of course, even when the valve is open, even if it is slightly less open, the flow of fluid does not matter, but in the closed state, the limit switch mounted on the valve visually displays the closed state and the controller Even if it is applied as, it is in a state that it is not completely closed by the tolerance which the uneven protrusion has.

Therefore, not only can the fluid leak during the process of recognizing the closed state and perform maintenance work on the valve or the valve peripherals, but in case of toxic or high temperature fluids, it may cause a safety accident that causes physical injury to the operator. It becomes the cause.

In addition, since the leakage or supply of the fluid is continuously made even in the closed state, many problems arise in use, and when the fluid needs to be precisely controlled, it is effectively removed at the desired pressure or amount even when the valve is opened or closed. It becomes impossible to do.

In addition, the operation shaft is not firmly fixed to the case, and there are severe clearances due to dimensional error, etc., and the opening and closing of the valve by the clearance and dimensional error of the control rim, the opening cam and the closing cam fixed or coupled to the operation shaft. Even if the closed position is adjusted, the contact between the open terminal and the closed terminal of the switch is repeated. It is displayed through the indicator installed on the upper part of the case, but the electric contact is not made by the controller. There are many problems, such as the inability to properly control the overall work in the control room.

Therefore, the present invention is invented to solve the above problems, the operating shaft is installed to penetrate the inside of the case installed on the upper portion of the actuator for operating the stem connected to the disk of the valve, and protrudes upward of the case The valve is composed of an indicator installed on the operating shaft to visually check the opening and closing state of the valve, and an operating shaft located inside the case and an operating part installed inside the case to apply the opening and closing of the valve to the controller as an electrical signal. In a limit switch for;

The operation unit is installed in the intermediate position of the operating shaft in contact with the open terminal and the closing terminal of the switch installed on one side of the case to install the opening rod and the closing rod to apply an electrical signal to the controller of the control room to open and close the valve, The opening rod and the closing rod is screwed with the opening hole and the closing hole formed to penetrate in the direction perpendicular to the axial center of the operating shaft, the tip of the opening and closing rod to be in contact with the opening and closing terminals By having the rear end of the opening and closing rods by forming a control head configured to close and move the opening and closing rods in the direction of the opening and closing terminal,

The opening and closing rods can be opened and closed in the direction perpendicular to the axial direction of the operating shaft to adjust them to the disc position of the valve. Therefore, the valve opening and closing state can be precisely applied to the indicator and controller, and the limit switch structure can be simplified. It is possible to achieve the purpose that production and assembly can be simplified.

The present invention is to improve the quality and durability of the limit switch by providing the ease of operation and the ease of production and assembly by simplifying the structure while being configured to easily adjust the opening and closing cam in contact with the terminal of the switch Of course, it is an invention having various effects, such as reducing the valve opening and closing error in the field and the control room where the valve is located to perform accurate judgment and efficient work.

1 is a perspective view of an exploded state showing a limit switch for a valve to which the technique of the present invention is applied.
Figure 2 is a longitudinal cross-sectional view of a coupled state showing a limit switch for a valve to which the technique of the present invention is applied.
Figure 3 is a cross-sectional view of the coupling state showing a limit switch for a valve to which the technique of the present invention is applied.
Figure 4 is an exemplary view showing a state applied to the valve the limit switch for the valve to which the technique of the present invention is applied.
Figure 5 is a block diagram showing a limit switch for a valve to which the prior art is applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of an exploded state showing a limit switch for a valve to which the technique of the present invention is applied, FIG. 2 is a longitudinal cross-sectional view of a coupled state showing a limit switch for a valve to which the technique of the present invention is applied, and FIG. Coupling state cross-sectional view showing the limit switch for the valve applied, Figure 4 is described together with an exemplary view showing a state applied to the valve limit switch for the technique of the present invention is applied.

Conventional valve limit switch 100, the operating shaft is connected to the actuator or the stem of the valve in the interior of the case 103 is installed on top of the actuator 102 for operating the stem connected to the disk of the valve 101 Install 104 through.

The operating shaft 104 protruding upward of the case 103 is provided with an indicator 105 for visually confirming the opening and closing state of the valve, and the operating shaft 104 and the case (located inside the case 103). 103, there is provided an operating unit 110 for applying the opening and closing of the valve to the controller as an electrical signal.

In the present invention, by improving the operation unit 110 to provide the ease of production and assembly of the limit switch while minimizing the adjustment and operation error, it is characterized in that it is possible to grasp the open and close situation of the valve in the field and control room.

The operation unit 110 is in contact with the open terminal 112 and the closing terminal 113 of the switch 111 installed on the inner side of the case 103 in the intermediate position of the operating shaft 104, the opening and closing state of the valve Install an opening rod 115 and a closing rod 116 to apply an electrical signal to the indicator 105 and the controller of the control room.

The opening rod 115 and the closing rod 116 are formed to penetrate the opening hole 117 and the closing hole 118 in a direction perpendicular to the axis center P of the operating shaft 104, and the opening hole. A screw 119 is formed in the 117 and the closing hole 118 to be coupled to the screw 119 formed on the shaft portion 120 of the opening and closing rods 115 and 116.

The tip of the opening and closing rods 115 and 116 is integrally or separately attached to the tip of the switch 111 so as to be in contact with the opening and closing terminals 112 and 113 of the switch 111, and the opening and closing rods 115 and 116. At the rear end of the), an adjusting head 122 is formed to allow the opening and closing rods 115 and 116 to approach and separate in the direction of the opening and closing terminals 112 and 113.

The middle of the opening and closing rods 115 and 116 is coupled to the opening and closing holes 117 and 118 formed in the operating shaft 104 so that the controlled opening and closing rods 115 and 116 may be controlled so as not to move in the adjusted state. Locking means 123 having a configuration such as a nut or a butterfly nut.

Looking at the state of use of the limit switch 100 for a valve applied to the technology of the present invention as described above are as follows.

The opening rod 115 and the closing rod constituting the operation unit 110 of the limit switch 100 in a state in which the disc of the valve 100 is operated to the maximum open position or in a state of operating the disc to the fully closed position. 116 checks whether the electrical connection is made through normal contact with the open terminal 112 or the closed terminal 113 of the switch 111.

Of course, in this process by releasing the locking means 123 located in the shaft portion of the opening rod 115 and the closing rod 116 to rotate in the forward and reverse directions using the adjustment head 122 in the free movement state of the operating shaft ( Access is made along the opening hole 117 and the closing hole 118 formed in 104.

Then, the screw 119 is formed in the opening hole 117 and the closing hole 118 and the shaft portion 120 of the opening and closing rods 115 and 116, so that it can be adjusted to a minute position. After the contact tip 121 is moved and adjusted to normally contact the opening terminal 112 and the closing terminal 113, the opening and closing rods 115 and 116 may be prevented from moving by using the locking means 123.

In addition, when the contact tip 121 is in contact with the open terminal 112 and the closing terminal 113, the operating shaft 104 is closed with the open terminal 112 in the operation process in consideration of the play of the operating shaft 104. It is natural to consider that the contact tip 121 may be in contact with the open terminal 112 and the close terminal 113 to generate an electrical signal even when the terminal 113 is spaced as far as possible.

The present invention can be adjusted according to the disc position of the valve by opening and closing the opening rod and the closing rod in a direction perpendicular to the axial direction of the operating shaft, it is possible to accurately apply the open and close state of the valve to the indicator and controller, as well as of the limit switch The simple structure has the advantage that the production and assembly can be made simple.

100; Limit switch 101 for valve; valve
102; Actuator 104; Working shaft
105; Indicator 110; Operating part
111; Switch 112; Open terminal
113; Closing terminal 115; Open rod
116; Closing rod 117; Opening Hall
118; Closing hole 121; Contact tip
122; Adjusting head 122; Locking means

Claims (2)

An actuating shaft installed through the case installed on an upper portion of the actuator for operating the stem connected to the disk of the valve;
An indicator installed on an operation shaft protruding upward of the case to visually check an open / closed state of the valve;
An actuating shaft disposed inside the case and an actuating part installed inside the case to apply opening / closing of the valve to the controller as an electrical signal;
The operation unit, the valve for installing the opening rod and the closing rod in contact with the open terminal and the closing terminal of the switch installed on one side of the case in the intermediate position of the operating shaft to apply an electrical signal to the controller of the control room to open and close the valve In a limit switch for;
The opening and closing rod is provided with a contact tip to contact the opening and closing terminal at the front end, and at the rear end of the operating shaft by forming an adjustment head to close and disengage the opening and closing rod in the direction of the opening and closing terminal. Screwing the opening hole and the closing hole so as to pass through in a direction perpendicular to the axis center;
The limit switch for the valve, characterized in that the middle of the opening and closing rod further comprises a locking means coupled to the opening and closing hole to regulate the opening and closing rod is not moved in the adjusted state. delete

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