JPH0757597A - Set pressure variable device for pressure switch - Google Patents

Abstract

PURPOSE:To easily change the set pressure from the case of a pressure switch. CONSTITUTION:A fixed frame 3 is fitted to a stub provided with a coil Bourdon' s tube 2, a moving frame 4 is supported on the fixed frame 3 rockably by spring pressure, and they are stored in a prescribed case 11. The moving frame 4 is provided with a limit switch 7 and a rocking type switch operation piece 8 for operating the limit switch 7, and an operation piece 10 provided at the tip of the Bourdon's tube 2 is hooked on the switch operation piece 8. A variable bolt 14 is provided through the case 11, and the tip of the bolt 14 is brought into contact with the pressing piece of the moving frame 4. When the variable bolt 14 is rotated from the outside of the case 11, the limit switch 7 is moved in the separating direction from the switch operation piece 8 via the moving frame 4 kept under spring pressure, and the operating set pressure can be simply and surely changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a set pressure varying device in a pressure switch, which is capable of easily changing the set pressure from outside the casing of the pressure switch.

[0002]

2. Description of the Related Art A conventional pressure switch is operated at a set pressure by displacing the Bourdon tube by the fluid pressure applied to the Bourdon tube and operating a limit switch opposite to the Bourdon tube due to the deviation of the Bourdon tube. I am trying. Then, the set pressure is changed by a mechanism provided in the container.

[0003]

Therefore, when changing the set pressure, it is necessary to operate by removing the front part or part of the container from the main body. For this reason, there is a drawback that it takes time to change the set pressure.

An object of the present invention is to make it possible to easily change the set pressure from outside the pressure switch.

[0005]

The present invention has been made to achieve the above object, and a fixed frame is attached to a stock fixed to a container and equipped with a coiled Bourdon tube, and the movable frame is attached to the fixed frame. Is swingably supported under spring pressure, the movable frame is equipped with a limit switch and a swing-type switch operation piece for operating the limit switch, and the operation piece provided at the tip of the Bourdon tube is locked to the switch operation piece. At the same time, the tip of the variable bolt provided on the housing so as to penetrate the housing contacts the pressing piece of the movable frame, and the limit switch is moved through the movable frame by the rotation of the variable bolt from the outside of the housing. The gist is that the operating set pressure is changed accordingly.

[0006]

[Function] A fixed frame is attached to a stock equipped with a coiled Bourdon tube, and the movable frame is supported so as to be swingable under spring pressure. The movable frame is housed in a predetermined container and at the same time, the movable frame. Equipped with a limit switch and a swing-type switch operation piece for operating the limit switch,
The operation piece provided at the tip of the Bourdon tube is locked to the switch operation piece. Then, a variable bolt is provided in the casing so as to penetrate therethrough, and the tip of this bolt is brought into contact with the pressing piece of the movable frame. Therefore, by rotating the variable bolt from the outside of the container, the limit switch can be moved from the switch operation piece to the contact / separation direction via the movable frame under the spring pressure, and the operation setting pressure can be changed easily and reliably. .

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A set pressure varying device for a pressure switch of the present invention will be described below with reference to the illustrated embodiment. In the figure, reference numeral 1 is a base of a pressure switch. The base 1 is housed and fixed in a predetermined pressure switch case, and a stock connected to a pressure fluid source is integrally provided on the base. Then, the straight end of the coil-shaped Bourdon tube 2 formed by spirally winding a pipe material or a flat pipe material a plurality of times is fixed to the stock of this base, and the pressure applied to the stock is transmitted to this Bourdon tube. Do as you do.

The tip of the coiled Bourdon tube 2 is made straight like the fixed side end, the end is closed to make a free end, and the operation piece 10 is projectingly provided at the tip of the Bourdon tube. When the coil portion of the Bourdon tube 2 is displaced by the fluid pressure applied to the tube 2, the free end portion is allowed to freely swing.

A fixed frame 3 is attached to the stock, and a movable frame 4 positioned above the fixed frame is swingably supported via a shaft 5 established at one end of the fixed frame, and the fixed frame 3 and A kick spring 6 is interposed between the movable frame 4 and the movable frame so that the movable frame 4 is always held at a predetermined position. The movable frame 4 is provided with a pressing piece 4a.

A limit switch 7 is fixed to the movable frame 4, and a switch operating piece 8 is swingably provided on a support shaft 9 projecting close to the limit switch 7, and one end of the switch operating piece 8 is attached. The operation piece 10 is hooked on the operation piece 10, and the other end of the switch operation piece is brought into contact with and pressed against the switch piece of the limit switch 7, whereby the operation piece 10 is moved in the direction opposite to the limit switch due to the displacement of the Bourdon tube. Switch operation piece 8 to support shaft 9
Is swung around, and the switch piece of the limit switch is pressed by the other end of the switch operation piece 8.

In order to change the pressure setting when the switch operation piece 8 hooks the operation piece 10 to operate the limit switch due to the deviation of the Bourdon tube, the interval between the switch piece of the limit switch and the switch operation piece is changed. Then do. This can be done by swinging the movable frame around the support shaft. For this reason, in the present invention, the adjustment bolts of the variable device protruding outside the housing are rotated.

As shown in FIG. 1, the set pressure varying device is a container 1
The variable bolt 14 is provided so as to pass through the side wall of 1. The nut 1 is attached from the inner wall surface of the casing to the bolt mounting bracket 12 that extends along the outer wall surface of the casing and penetrates the inner wall surface of the casing.
3 is screwed to be fixed to the housing, the variable bolt is inserted so as to be screwed to the bolt mounting bracket, and the tip of the variable bolt is brought into contact with the pressing piece to press the pressing piece. .

As shown in the figure, a fixing nut is provided on the bolt mounting bracket so that the variable bolt does not rotate inadvertently. When the variable bolt is rotated, the fixing bolt is loosened to rotate the variable bolt, and after the necessary adjustment, the fixing bolt is tightened again. The pressing direction of the pressing piece by the variable bolt is set to be opposite to the spring action direction of the kick spring.

Therefore, when changing the set pressure in the device constructed as described above, if the fixing nut is loosened and the variable bolt is rotated, the pressing force of the pressing piece by this bolt becomes weak and the variable bolt is retracted. The movable frame swings about the support shaft by the kick spring. That is, the movable frame swings counterclockwise in FIG. 1, and the switch piece of the limit switch is separated from the switch operation piece. This is for high pressure because the limit switch does not operate unless the amount of deviation of the Bourdon tube increases.

On the contrary, when the variable bolt is tightened, the pressing piece is pushed by the tip of the bolt and swung clockwise against the elastic force of the kick spring, and the switch piece comes close to the switch operating piece side. A slight deviation of the Bourdon tube causes the limit switch to operate, and it will operate even at low pressure. Thus, the set pressure can be easily changed by rotating the variable bolt from the outside of the container.

After changing the set pressure, the fixing nut is tightened again to fix the variable bolt so that the variable bolt is not loosened unintentionally by vibration of the pressure gauge or the like.

[0017]

The set pressure varying device in the pressure switch of the present invention is fixed to the casing, and the fixed frame is attached to the stock equipped with the coiled Bourdon tube, and the movable frame can be oscillated under spring pressure. The movable frame is equipped with a limit switch and an oscillating switch operation piece for operating the limit switch.The operation piece provided at the tip of the Bourdon tube is locked to the switch operation piece and penetrates the container. Since the tip of the variable bolt provided on the housing is brought into contact with the pressing piece of the movable frame, the variable bolt can be rotated from the outside of the housing without removing the housing to limit the movement through the movable frame. There is an advantage that the operating set pressure can be easily changed by moving the switch.

[Brief description of drawings]

FIG. 1 is a plan view of essential parts showing an embodiment of a set pressure varying device in a pressure switch of the present invention.

FIG. 2 is a perspective view of the same appearance.

FIG. 3 is an external view of a pressure switch provided with a set pressure varying device of the present invention.

[Explanation of symbols]

 1 stock 2 coiled bourdon tube 3 fixed frame 4 movable frame 5 support shaft 6 kick spring 7 limit switch 8 switch operation piece 9 support shaft 10 operation piece 11 instrument housing 12 bolt mounting bracket 13 nut 14 variable bolt 15 fixed nut

Claims (1)

[Claims] 1. A fixed frame is attached to a stock fixed to a container and equipped with a coiled Bourdon tube, and a movable frame is swingably supported under spring pressure on the fixed frame,
The movable frame is equipped with a limit switch and a rocking type switch operation piece for operating the limit switch.The operation piece provided at the tip of the Bourdon tube is locked to the switch operation piece, and it also penetrates the case to make it a case. The tip of the provided variable bolt is brought into contact with the pressing piece of the movable frame, and the limit switch is moved through the movable frame by the rotation of the variable bolt from the outside of the container to change the operating set pressure. A variable set pressure device for a pressure switch.