JP2587329B2 - Processing method of rotary disc valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a rotary valve having a seat having a spherical or partial spherical surface.

[0002]

2. Description of the Related Art A seat of a valve body is formed into a spherical surface or a partial spherical surface .
As the formed valve, the concentric type (general ball valve) in which the ball center of the valve body coincides with the center line of the seat ring, and the ball center of the valve body is eccentric with respect to the center line of the seat ring There is an eccentric type. FIG. 6 shows a conventional example of a concentric rotary valve. This rotary valve 1 has a spherical valve body 4 having a through hole 5 in a flow path 3 of a valve body 2 and the valve body 4 is formed as described above. By rotating the valve 3 with a valve shaft 6 orthogonal to the center line of the valve body 2, the flow path 3 is opened, and the flow rate is controlled in accordance with the rotation angle. The outer peripheral surface of the valve element 4 is formed into a spherical surface whose spherical center coincides with the center line of the seat ring 7 provided on the upstream side of the flow path 3, and is closely contacted with the seating surface 8 of the seat ring 7. The portion 4A is formed. FIG. 7 shows a conventional example of an eccentric rotary valve. In this rotary valve 11, a valve plug 12 has a disc-shaped valve body 12A having an outer surface forming a spherical seating portion 13, and a valve plug 12 formed integrally with a back surface of the valve body 12A. A pair of upper and lower arms 12B and 12C protruding from the valve shaft 6, the upper arm 12B is fitted and fixed to the valve shaft 6, and the lower arm 12C protrudes into the valve body 2. obtained by rotatably supported by, by decentering the spherical center of the seat 13 from the rotation center of the plug, typically i.e. the seat ring spherical seat 13 of Oite <br/> valve 12A fully closed 7 Is closely contacted with the sheet portion 8 . In this state, when the valve body 12A is rotated by the valve shaft 6 , the spherical seating portion 13 separates from the seat portion 8 and opens .

[0003]

In the above-described concentric rotary valve 1, the spherical seating portion 4A is processed in such a manner that the spherical center of the seating portion 4A coincides with the axis of the valve body 4. A predetermined spherical surface can be easily obtained by rotating the cutting blade 4 around its central axis to cause the cutting blade to follow the model, or by reciprocating in an arc shape by numerical control. However, in the case of the concentric type, since the valve body 4 is always in sliding contact with the seat ring 7, there is a problem that the seat portion 4A and the seat portion 8 are severely worn and lack durability. On the other hand, in the case of the eccentric rotary valve 11, the seat ring 7 and the valve body 12A come into contact only when the valve is closed.
3 and the seat portion 8 are less worn and have excellent durability. However, the rotational center of the valve body 12A and the spherical center are eccentric,
Since it is, Oite the fabrication of the valve body 12A along with match the eccentricity of the eccentricity precisely valve body 2, it is necessary to ensure high spherical center accuracy, a problem that manufacture is troublesome there were.

[0004] Accordingly, the present invention has been made to solve the conventional problems described above, it is an object of the concentric type rotary valve, easily processed seat
To close the valve closing area with high precision
To provide a method for processing a valve body.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and comprises a spherical surface or a partial spherical surface.
It has a seat that has a seating part that opens and closes the opening of the seat ring.
The seat ring is closed when the seat is fully closed.
A valve closing area portion, and an eccentric curved valve which is provided continuously on the seat closing position side of the valve closing area portion and gradually moves away from the seat portion of the seat ring as the valve body rotates in the opening direction. A method for processing a valve body for a rotary valve configured with an open area portion, wherein a cutting blade provided eccentrically on a rotation axis orthogonal to an axis of the valve body is used, and the valve body is rotated about its axis. Processing the valve closing area of the seat portion into a spherical surface by the cutting blade by rotating the rotary shaft together with rotating the rotary shaft about the axis of the valve body and rotating the rotary shaft. Machining the valve opening area of the seating portion into an eccentric curved surface by the cutting blade by moving the cutting blade in the direction.

[0006]

When the valve body and the cutting blade are rotated about axes orthogonal to each other in processing the seating portion, the valve closing area can be processed into a spherical surface. Further, when cutting is performed while feeding the cutting blade in the direction of the valve body, a valve opening region portion formed of an eccentric spherical surface that is not in contact with the seat portion of the seat ring can be formed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. 1A and 1B show a fully closed state and a fully opened state of a rotary valve according to the present invention, and FIG. 2 is a sectional view of the rotary valve. In these figures, the valve device 20
A valve plug 21 is provided at the inner end of the valve shaft 6 and disposed in the valve body 2. The valve plug 21 has a valve body 2 having a spherical surface or a partially spherical surface with a hollow inside.
2 and cylindrical bearings 23 and 24 integrally protruding from the upper and lower surfaces of the valve element 22, respectively, and a belt-like spherical seat that is long on the outer peripheral surface of the valve element 22 in the rotation direction of the valve shaft 6. The part 25 is formed so as to be raised one step, and the opening 26 forming the equal percent characteristic part is formed in the spherical seat part 2.
5 is formed so as to overlap with one end. The width D of the spherical seat portion 25 is set slightly larger than the inner diameter A of the seat portion 8 of the seat ring 7 (D> A). The valve closing region I of the spherical seating portion 25 which is seated on the seat portion 8 when the seat ring 8 is fully closed and closes the seat ring 7 is formed as a spherical surface having a spherical center coincident with the rotation center O of the valve plug 21. The valve opening area II provided with 26 has a radius of curvature such that it is farther from the seat portion 8 of the seat ring 7 from a point P passing the seat closing position in a manner substantially in proportion to the rotation angle θ of the valve body 22. The spherical center is smaller than the closed region I and the spherical center is eccentric from the rotation center O of the valve plug 21. Therefore, after passing the seat closing position P, the contact surface pressure with the seat ring 7 decreases, and the wear of the spherical seating portion 25 can be reduced.

The inner end of the valve shaft 6 is fitted to the upper bearing portion 23 and integrally joined by welding or the like, and the lower bearing portion 24 is provided with a stud 14 projecting from the inner surface of the valve body 2. It is rotatably supported by. And the valve shaft 6
Of the lid 2 that closes the upper opening 27 of the valve body 2
8 penetrates through a center hole 29 via a packing 30 and protrudes to the outside.

FIG. 3 is a view for explaining a method of processing the valve body 21. In processing the spherical seating portion 25 of the valve plug 21, first, a plug material manufactured by casting or the like is prepared. At this time, the outer diameter and length of the bearing portions 23 and 24 are processed to predetermined dimensions,
The opening 26 is formed in a predetermined shape, and the valve shaft 6 is attached to the bearing 23. The plug material made of the semi-finished product is attached to a machine tool together with the valve shaft 6 and is rotated at a constant speed about the axis 32 of the valve shaft 6. This rotation speed is 2r. p. m. The cutting blade 35 for cutting the spherical seating portion 25 is provided on the arm 3 of the rotating shaft 36.
7, it is eccentric with respect to the rotation shaft 36. The rotation shaft 36 is disposed such that its axis 38 intersects the axis 32 of the valve shaft 6 substantially perpendicularly,
500-800r. p. rotated by m.

In this case, the radius of rotation of the cutting blade 35, that is, the distance r to the center of the rotating shaft 36 (for example, 18 mm)
And the width D of the spherical seating portion 25 and the inner diameter A of the seat ring 7 (FIG. 2) are set so as to satisfy the relationship of A <D <2r. When cutting the valve closing area I of the spherical seat 25, the valve plug 2
1 is rotated around the axis 32 of the valve shaft 6 at a low speed, and is advanced by a predetermined amount while rotating the rotation shaft 36 around the axis 38. When the cutting blade 35 cuts the valve closing region I, the spherical center is A predetermined spherical surface coinciding with the axis 32 of the valve body 22 is obtained. The size of the spherical surface is determined by the amount of forward movement of the cutting blade 35. When the amount of movement is small, the distance from the rotation center of the valve plug 21 to the cutting blade 35 is large, so that the spherical surface has a large radius, and when the amount of movement is large. Since the cutting blade 35 approaches the valve plug 21, the cutting blade 35 has a spherical surface with a small radius. At the time of cutting the valve open area II, since the spherical center of the valve open area II is eccentric from the axis 32 as described above,
From the point past the valve closing position P of the spherical seat 25,
The cutting blade 3 is substantially proportional to the rotation about the axis 32.
5 is moved in the direction of the valve body 21 to synchronize the rotation of the valve body 21 with the feed of the rotating shaft 36.

When cutting the spherical seating portion 25, a machining machine such as an NC lathe is used, and a pulse motor or a servomotor is used to move and position the valve plug 21 and the cutting blade 35. Further, the positions of the valve plug 21 and the cutting blade 35 are determined by a signal sent from the sequence controller according to the processing procedure. The rotational position of the valve plug 21 and the axial position (θ, x) of the cutting blade 35 maintain the relationship shown in FIG.
Changes over time. That is, the rotation of the valve plug 21, the rotation of the cutting blade 35, and the movement of the cutting blade 35 are synchronized.

FIG. 5 is a view showing cutting marks formed on the surface of the spherical seat 25. As shown in FIG. The cutting marks 40 are formed on the valve plug 2
When the axis 32 of the first shaft 32 and the axis 38 of the rotating shaft 36 intersect with each other, the cutting blade 35 cuts the valve closing area I evenly. (Cross hatch). Therefore, it is possible to determine whether or not an accurate spherical surface has been obtained only by visually inspecting this pattern, and it is not necessary to inspect a special sphericity. Furthermore, the axis 3 of the axis 32 in the valve plug 21 rotates shaft 36
8 is not necessarily perpendicular to the surface because it is spherical cutting, and may be inclined in the left-right or front-rear direction, but substantially intersect with each other in order to obtain a true spherical valve closing region I. Is necessary. In the cutting of the valve closing region I, the cutting portion of the cutting edge of the cutting blade 35 merely rotates, unlike the conventional circular reciprocating movement. Will not change. Therefore, it is not necessary to perform special correction control to obtain a true spherical surface. On the other hand, in the cutting of the valve opening area II, the amount of eccentricity of the valve opening area II becomes irrelevant (because it separates from the seat portion 8 of the seat ring 7). Gone, high
No processing accuracy is required.

[0013]

The rotary valve according to the present invention as described above
According to the processing method of use valve body, it a spherical or partially spherical
It has a seat that has a seating part that opens and closes the opening of the seat ring.
The seat ring is closed when the seat is fully closed.
Valve closing area and the seat closing position of the valve closing area
When the valve body is provided continuously to the
Gradually release from the seat of the seat ring
Rotary valve with eccentric curved valve opening area
A method of processing a body, comprising: a rotation orthogonal to an axis of the valve body.
Using a cutting blade provided eccentrically to the axis, the valve body is moved along its axis.
And the rotation axis is rotated.
This allows the valve closing area of the seat to be
And processing the valve body around its axis.
While rotating the rotary shaft and rotating the rotary shaft
Seated by the cutting blade by moving in the body direction
Machining the valve opening area of the part into an eccentric curved surface.
Therefore, the valve closing region of the spherical seating portion can be formed with high sphericity.

[Brief description of the drawings]

FIGS. 1A and 1B are views showing a fully closed state and a fully opened state of a rotary valve according to the present invention.

FIG. 2 is a sectional view of the rotary valve.

FIG. 3 is a view for explaining a method of processing a valve element.

FIG. 4 is a diagram illustrating a rotational position of a valve plug and an axial position of a cutting blade.

FIG. 5 is a diagram showing cutting marks formed on the surface of the spherical seating portion.

FIG. 6 is a sectional view showing a conventional example of a concentric rotary valve.

FIG. 7 is a sectional view showing a conventional example of an eccentric rotary valve.

[Explanation of Signs] 6 ... valve shaft, 21 ... valve plug, 22 ... valve body, 23, 2
4 ... bearing part, 25 ... spherical seat part, 26 ... opening, 32 ... valve
Axis of shaft, 35: Cutting blade, 36: Rotating axis, 38: Rotating axis
Axis.

Claims (1)

(57) [Claims] 1. A seat comprising a spherical surface or a partial spherical surface.
A valve body for opening and closing the opening of the seat ring.
The valve is closed to close the seat ring when the seat is fully closed.
Area and the valve closed area side to the seat closed position side
Before the valve element rotates in the opening direction.
Eccentric songs that gradually move away from the seat of the seat ring
How to process a valve body for a rotary valve composed of a planar valve opening area
Eccentric to a rotation axis orthogonal to the axis of the valve body.
Using the cutting blade provided in the above, the valve body is centered on its axis.
By rotating the rotating shaft while rotating
The valve closing area of the seat is made spherical by the cutting blade.
Machining and rotating the valve body about its axis
While rotating the rotating shaft in the direction of the valve body.
The valve of the seat is opened by the cutting blade
Machining the region into an eccentric curved surface.
A method of processing a valve element for a rotary valve.