JPS5940073A - Device for attenuating acting force of valve rod for speed regulating valve - Google Patents

Abstract

PURPOSE:To reduce a force required by a governor and unnecessitate regulation or the like of a spring by a method wherein a pressure in the valve box of the speed regulating valve is applied to a link mechanism through a cylinder communicating with the valve box and the force of the speed regulating valve rod, applied to the link mechanism and caused by the pressure in the valve box, is cancelled by the effect of the cylinder. CONSTITUTION:The governor 11 is connected pivotably to the link mechanism 13 at a connecting point 12a through a speed regulating output shaft 12. The link mechanism 13 is provided on a fixed supporting body 14 pivotably about a supporting point 15. The valve rod 16 is attached at an intermediate part between the connecting point of siad link mechanism 13 and the output shaft 12 and the supporting point 15 pivotably about a connecting part 16a while a distance between the supporting point and the connecting part is adjusted so as to balance to the force acting on the valve rod 16 and a piston 23, thereby unnecessitating the regulation of the spring.

Description

DETAILED DESCRIPTION OF THE INVENTION In a steam turbine or the like, a speed governor operates a speed governor valve via a link mechanism or the like to fully adjust the steam meter that sends steam to the turbine, thereby fully controlling the turbine rotational speed.

The general speed governing mechanism of steam turbines that has been used since the Congregation of Song Dynasty is explained with reference to Figure 1.
Set the T5ze's turbine rotation losing streak and governor output shaft! moves in and out to move the link mechanism 3. The link mechanism 3 is rotatably attached to the support body G at a fulcrum S, and the link mechanism 3 has a connecting point S for the output shaft. A valve stem A is connected between the valve stem A and the fulcrum S, and the sliding valve 7, which is fixed to the valve stem A, is inserted into the valve body via the link mechanism 3 and the valve stem A by the output shaft of the governor/. move. Depending on the position of the slide valve 7, high-pressure steam is sent from the steam source to the turbine along the routes shown by arrows A1, A2, and A3.

At this time, a pressure corresponding to the cross-sectional area of the valve stem B at the fixed part with the sliding valve 7 and the steam pressure inside the valve box is applied to the valve stem 6, and the link 4fJ, t'fη3 is being pressed.

Conventionally, the .theta. spring/.theta.'t is generally connected to a mechanical mechanism, and the force of the spring is used to counteract the pressure inside the valve body acting on the valve stem 4.

However, the force generated in the spring /θ changes depending on the opening degree of 1 sho, that is, the position 14 on the left and right of the valve stem B, and the pressure inside the valve box 2 changes depending on the operating conditions of the steam turbine. It is impossible to always cancel out the force acting on the valve stem B with the force generated in the spring /θ. For this reason, the speed governor must be able to counteract the above-mentioned uncancelled force by simply operating the valve stem B and the link mechanism in its entirety.

In particular, when operating a steam turbine at normal pressure at low quality A::j, the pressure inside the valve box 7 is low and the high 1f11
1. Due to the fast spring force, it is necessary to resist.

In order to adjust the spring weight, it is necessary to adjust the spring while the turbine is rotating, while pressure is still present in g+57 inside the valve box.
There is a danger of being left behind.

Other than the above (l, spring/θ, omitted, governor/
There are also valves that use force to counteract the force acting on the valve stem. In this case, it is necessary to use a powerful, ie large and expensive governor. In the case of a powerful speed governor, the amount of energy consumed by the speed governor is large, and therefore the energy loss is also large.

An object of the present invention is to overcome the above-mentioned problems, to apply pressure inside the valve box of the regulating valve to the link mechanism through a linkage formed by communicating with the valve box, and to apply pressure to the regulating valve stem of the link mechanism VC. The force due to the pressure 11'C in the box is offset by the effect VC of the cylinder, reducing the force required by the governor, thereby reducing the need for spring adjustment and/or reducing the effect force. An object of the present invention is to provide a governor valve rod acting force reduction device that can use a small governor.

The present invention includes a link mechanism rotatably supported on a fulcrum, a speed governor connected to the link mechanism via an output shaft, a valve box, and a valve that adjusts the amount of steam in the valve box. A governor valve provided with the valve, a valve stem having one end fixed to the valve and the other end joined to the link mechanism, communicate with the valve box so that the steam pressure inside the valve box is bent inward. 71. And, the slide 1 is self-installed in the printer and the link mechanism 71. The diameter of each of the valve stem and the piston, and the link surface 1 of the valve stem.
The distance between the fulcrum and the respective positions of the joint part with the piston and the link mechanism with the valve stem ε
The purpose of the notation can be achieved by means of a device for reducing the force acting on the governor valve rod of a steam turbine, which is selected so that the pressure inside the valve box acting on the valve body is offset by the piston. can.

1. In FIG. 3, the speed governor // is connected to a rotatable VC link at the junction point /, 2a via the speed governor output shaft /. Machine 19/J
join to. The link mechanism 7.3 is rotatably mounted on a fixed support (fixed to the valve body /g in the figure) at a fulcrum /S. The valve stem /6 is connected to the joint between the link mechanism 73 and the output shaft /, 2 at the junction /, and the intermediate part between 2a and the fulcrum /j.
At 4a, it is rotatable for a few seconds.

On the other hand, the JAi floor valve V is a steam population
1, inside/9 of valve box/g has an annular sheet dθ
is inserted, and a steam vent 2θa is bored in this.

Annular/-1-, Jθ ((Cup-shaped sliding valve/7 is slidably inserted fL, through hole/7 is at the bottom of the sliding valve/7
When a is bored, a valve stem/O is fixed to the bottom of the sliding valve/7, and the valve stem/O protrudes from the end of the valve box/g, and at the tip/O, a link mechanism 73 Combine with.

A pipe, 2/, which communicates with the inside of the box, is connected to the 7F box/, and the pipe, , l/, is fixed to and communicates with the cylinder 22.

A piston 13 is slidably attached to the cylinder 12, and the tip of the piston 23 is rotatably connected to a link mechanism 73 at a joint 23aVCk. . The joint part 6a of the valve stem/B and the joint part 23a of the piston 33 are the fulcrum/
Located on opposite sides of S.

When operating a steam turbine using the above device, the speed governor sets the rotational speed of the turbine according to conditions such as steam temperature and pressure. The speed governor// is set by hydraulic pressure, electricity, etc. (depending on the speed governor output shaft/, l fully enters and exits 1,
This output) 7.2 movement causes the link mechanism 73 to rotate around the fulcrum/Sf, and this rotation causes the slide valve/7 to rotate the valve stem/B and rotate the ring: Y Nto! Fully slide within θ. Due to this sliding, the opening degree of the steam passage, lOa, is decreased, and the amount of steam flowing from the steam source to the turbine is adjusted along the paths shown by arrows S1, S2, and S3, and the turbine is rotated at a predetermined speed.

Here, the force pushing the valve stem/B (from right to left in the figure) is, for example, the pressure inside the valve box/9 P f j 3 kg7cm2
G, assuming that the diameter of the valve stem/B is f73cm, -X A3-2) 15-B/S is 7, G One cylinder, 2. The pressure inside the valve box/'7' is communicated inside the cylinder, The piston 23 is pushing the link mechanism 73 against the pushing force of Ibori/Otsu.

Now, the distance fX+ between the fulcrum/S and the joint/Ot a, the fulcrum 7.
5 and piston, : 13 joint, total distance from No. 3a x2
, the diameter of the valve stem is dl, the diameter of the piston 33 is ff1
When d2, dl, d2, X
To select L and Xl, - valve stem/O and piston, 2
3 can be balanced by tracing the entire link mechanism 73.

Therefore, the force acting on the output shaft of the governor, which adjusts the entire rotational speed of the turbine by moving the valve stem, is independent of the pressure inside the governor valve box. , But, Benbo/Otsu,
The link mechanism 7.3 only needs to overcome the inertial force and frictional force of the moving parts.

In the above V ((ν), each joint in the link mechanism /3 is shown from the top of the drawing υ: governor-like output shaft joint /, 2a, valve stem joint / Oa, fulcrum /S, cylinder joint. , ] 3a, but the order of this arrangement can be changed if necessary.Also, sliding valves/7 valves, traps, and other valves of the above type can also be used. be.

According to the present invention, the force generated on the output shaft of the speed governor can be reduced, and therefore, it is possible to use all small items with a larger weight than the speed governor used in the conventional device. . In addition, the conventional spring is used, and the advantage of the device d is that there is no need to adjust the spring. /The fear of redundant changes in all stem characteristics is also eliminated.

Note that the present invention is applicable not only to steam turbines but also to cast turbine hydraulic turbines V (Oguchi IJ c'J'M'ii).

[Brief explanation of the drawing]

Figure 1 shows a part of a conventional turbine A speed 1 configuration. The figure is a partial diagram of the present invention.1°//...Governor/! Output shaft/3 ・Link mechanism /G ・Support 7.5-...
Fulcrum /6 ・Valve stem /7...Sliding valve
/ to Valve box/2・Inside the valve box, 2.2・Nlinda,,! ! 3
・Piston patent applicant Chiyoguchi 1-Ni Construction Co., Ltd. No. 1
figure

Claims (1)

[Claims] a 7” link mechanism rotatably supported at a fulcrum;
A speed governor is connected to the link mechanism via an output shaft, a speed governor is provided with a valve box and an fP that adjusts the amount of steam in the valve box, and one end is fixed to the valve and the other end is connected to the valve box. a valve stem joined to the link mechanism; a cylinder communicating with the valve box to allow steam pressure inside the valve box to flow therein; and a cylinder slidably disposed within the cylinder and having one end joined to the link mechanism. between the diameter of the valve stem and the piston valley, the position of the joint of the valve stem with the link mechanism and the joint of the piston with the link mechanism, and the fulcrum. is selected such that the pressure inside the valve box acting on the valve stem is offset by the piston.