JPH0158392B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a low-noise valve with a noise prevention function.

[Prior art]

Conventionally, this type of low-noise valve has been disclosed as Japanese Patent Publication No. 54-28973 and Japanese Patent Publication No. 48-25333.
The former is a method in which a large number of porous cylinders are stacked and fitted together, and the latter is a method in which a large number of labyrinth-like passages are formed on each surface of laminated disks, or a uniquely shaped hole is provided in each disk.

However, in the low-noise valve configured in this way, the shape of the flow path is unnecessarily complicated.
For this reason, the fluid flow draws unpredictable streamlines,
Moreover, this streamline changes depending on the flow rate according to the valve opening degree. As a result, not only the controllability deteriorates, but also
It has the disadvantage of reducing the valve capacity (C _v value) and reducing the outflow efficiency.

[Summary of the invention]

The present invention was developed in view of the above circumstances, and has an extremely simple structure in which a large number of annular disks having smooth flow path surfaces are stacked at slight intervals and arranged on the outside of the peripheral wall of the cage. The present invention provides a low-noise valve that not only prevents cavitation noise but also has good controllability and improves outflow efficiency.
Hereinafter, the configuration and the like will be explained in detail by referring to embodiments shown in the drawings.

〔Example〕

FIG. 1 is a cross-sectional view showing an embodiment of the low-noise valve according to the present invention, FIG. 2 is a cross-sectional view showing the main parts of the low-noise valve, and FIG. 3 is a cross-sectional view showing the annular disk of the low-noise valve. The perspective view, FIGS. 4a and 4b, are a sectional view and a plan view showing the ribs on the annular disk. In these figures, the reference numeral 1 is the valve body, and there is a valve chamber 2 inside.
is formed, and this valve chamber 2 has an inlet 3 and an outlet 4.
It opens downward and to the sides of the valve body 1. Reference numeral 5 denotes a cylindrical cage, which is disposed within the valve chamber 2, and has valve seats 6, 7 and a plurality of fluid passage windows 8 provided on its peripheral wall. Reference numeral 9 denotes an annular holding plate, which is fixed to the outside of the peripheral wall of the cage 5 above and below the fluid passage window 8 by welding the entire circumference. Reference numeral 10 denotes an annular disk having a flat flow path surface 10a, and a large number of ribs 11 are radially provided on the upper surface by beads formed during press working or welding. The body 12 of the cage 5 is formed by arranging a large number of annular disks 10 in the axial direction at slight intervals between the presser plates 9, that is, at intervals equal to the height of the ribs 11. . That is,
A large number of annular disks 10 are stacked in the axial direction at slight intervals, and are arranged on the outside of the circumferential wall of the cage 5. In this case, it is desirable that adjacent annular disks 10 be positioned so that their respective ribs 11 do not overlap with each other.
Note that the stacking interval of the annular disks 10 is determined based on the surface roughness, material, etc. of the plates, in addition to taking into account the type and flow rate of the fluid. In other words, each annular disk 10 may overlap in a boundary layer formed in the flow path. In addition, the annular disk 10 is
If the inner periphery and the outer periphery are formed with a sufficient width so that the lengths are significantly different, it is more effective in sinking the energy of the fluid. 13 is a piston type plug having seating portions 14 and 15 that can be brought into close contact with both the valve seats 6 and 7;
It is disposed inside the cage 5 including the body 12 so as to be movable up and down. The valve chamber 2 is also opened upward so that the cage 5 can be inserted and removed.
Two upper and lower lid members 16 and 17 cover the valve body 1 and the lid member 16, respectively, to cover this opening.
Of these cover members 16 and 17, the upper cover member 17 supports the valve shaft 18 in a slidable manner.

Therefore, when the piston-type plug 13 is raised by actuation of an actuator (not shown),
As shown by the arrow in the figure, the fluid flowing into the cage 5 from the inlet 3 passes through the fluid passage window 8, passes radially between the annular discs 10, and flows out to the outlet 4.

In this case, the flow path area formed between the annular disks 10 is wider on the outlet side than on the inlet side because the lengths of the inner and outer circumferences of the annular disks 10 are different. The passing fluid obtains a pressure recovery effect as a bench lily effect, and its outflow amount increases. At this time, the fluid has an annular disk 1
Since the viscous frictional force generated between the flow path surface 10a and the flow path surface 10a is added, and the flow path area gradually increases, the fluid energy can be effectively dissipated and the pressure recovery effect can be gradually obtained. Therefore, generation of strong turbulent vortices and shock waves on the downstream side of the flow path can be prevented.

Note that in this embodiment, a large number of annular disks 1
0 is simply disposed on the outer side of the circumferential wall of the cage 5, but the present invention provides an arrangement in which each annular disk 1 is simply disposed on the outer side of the circumferential wall of the cage 5.
By inserting the rod 20 for preventing disc positional displacement through the disk 0, positional displacement can be prevented.

In addition, in the embodiment, the annular disk 10 has a flat flow path surface 10 because it can be manufactured economically.
Although the present invention is not limited to this, it may have a curved flow path surface 10b as shown in FIG. 6. In short, as long as it is an annular disk having a smooth flow path surface, it can be implemented in the same manner as in the embodiment.

Further, in this embodiment, an example in which the ribs 11 are provided on the upper surface of the annular disk 10 is shown, but the present invention provides bosses 2 on the upper surface of the annular disk 21 as shown in FIG.
There is no problem even if 2 is provided. In this case, the boss 22 can be formed by welding sputtering or pressing, as shown in FIGS. 8a and 8b.

〔Effect of the invention〕

As explained above, according to the present invention, a large number of annular disks having smooth flow path surfaces are stacked in the axial direction at slight intervals and are arranged on the outside of the peripheral wall of the cage, so the structure is extremely simple. Moreover, the fluid energy is destroyed by the viscous friction caused by the flow path surface of the annular disk, and the generation of cavitation noise can be reliably prevented. Furthermore, since there is no zigzag portion in the fluid flow path, there is no collision of fluids and no turbulence occurs. Therefore,
The flow becomes relatively smooth and the outflow efficiency can be improved. Furthermore, since the monotonous flow of fluid flowing between the annular discs does not change depending on the flow rate, there is also the effect that controllability is improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the low-noise valve according to the present invention, FIG. 2 is a cross-sectional view showing the main parts of the low-noise valve, and FIG. 3 is a cross-sectional view showing the annular disk of the low-noise valve. 4a and 4b are cross-sectional views and plan views showing ribs on the annular disk, FIG. 5 is a perspective view showing an example of holding the annular disk, and FIG. FIG. 7 is a sectional view showing one embodiment, and FIG.
A perspective view showing the embodiment, and FIGS. 8a and 8b are cross-sectional views showing the boss on the annular disk. 5... Cage, 10... Annular disc, 10a...
Channel surface, 12...body, 13...piston type plug.

Claims (1)

[Claims] 1. A large number of annular disks having smooth flow passage surfaces are stacked in the axial direction at slight intervals, and are arranged on the outside of the peripheral wall of a cage having fluid passage windows, and a piston type is installed on the inside of the peripheral wall of this cage. A low-noise valve characterized by a plug that can be moved up and down.