JPS5965673A - Poppet valve or check valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in valve seats for poppet or check valves.

Most of the conventional poppet valve sizes and check valves are
It has a hemispherical head that mates with a seat formed within the valve chamber. In many cases, the valve seat is configured so that metal-to-metal contact occurs, and if it is incorrectly installed or wears out, a slight misalignment will occur between the valve body and the valve seat.
It was difficult to ensure that the valve seat was in proper contact with the valve seat.

This results in leakage in the valve. This creates constant maintenance problems, making such valves particularly unsuitable for use in high speed cycling operations.

In recent years, attempts have been made to overcome the above-mentioned problems by using valves using valve seat mechanisms incorporating O-rings. This type of valve is constructed with an O-ring attached to the valve member such that the O-ring seats on a shoulder formed in the valve chamber. However, such valves have not proven completely satisfactory for use in high speed operations. When compressive loads are repeatedly applied to the O-ring, the O-ring deforms beyond the elastic limit of the material from which it is made. This damage to the valve seat necessitates frequent replacement of the O-ring.

The object of the present invention is to eliminate the above-mentioned drawbacks of conventional valve seats, and to provide a valve seat that is simple and strong in construction, and that can be used for a very long period of time at high speed cycles without easily damaging the valve seat. This is to provide a valve that can be used. For the above purpose, the poppet valve or check valve of the present invention has (+)
(n) an annular valve seat; (lit) an O-ring retaining member movable within the valve chamber, having an O-ring retaining chamber and projecting towards the annular valve seat; and a Q-IJ song made of a resilient material which is located in the retaining member and forms a leakage barrier between the valve member and the annular valve seat when the valve is closed. B. The O-ring retaining member has: (v) a head portion remote from the valve member; (vl) a groove between the head portion and the valve member, the groove being (1) inwardly from the head portion; a first conical portion having a cone angle of not more than about 25°; (b) at least about (90” −
2γ) (where γ is the formula: (Here, R6 is the radius of the cross section of the Q-IJ song when the valve is open, and Xl is the radius of the cross section of the O-ring when the valve is closed. (c) The cone angle of the curved band is increasing (90" - 2γE) given by the formula.

(Here, R8 is the same as Itoman, and is the reduced length of the radius of the O-IJ song cross section at the conical part where the slope of the X-curved band increases.) The O-ring retaining member consists of a curved band layer between the two conical portions, which forms a smooth transition between the two conical portions, so that the O-ring retaining member is able to close the valve and prevent the O-ring from deforming during valve closing. There is no interference with the O-ring, that is, there is no pressure on the O-ring.

The present invention will now be described in detail with reference to the accompanying drawings, which illustrate embodiments of the invention.

Referring first to FIG. 1, a poppet or check valve according to the invention includes a housing 1 defining a valve chamber 2. As shown in FIG. A valve member 8 is movably arranged in the valve chamber 2, and in the present invention the valve member 5 is guided to reciprocate by a guide member 4 fixed in the valve chamber 2.

The valve box 1 includes an inlet 5 and an outlet 6. In order to support one end of the compression spring 8, a portion of the outlet 6 is widened in diameter at 7, and the other end of the compression spring 8 is a portion of the valve member 3 with a larger diameter corresponding to the portion 7. It is engaged with 9.

The inlet side of the valve chamber is closed by an annular insert 10, which is connected to the seat 1 of the mechanical seal.
1 and 7, and the elastomer of the valve member 3.
- Forms the seat 12 of the seal. As is clear from the figure, the seats 11 and 12 are spaced apart from each other.

Seats 11 and 12 are stepped inward,
The seat surfaces of both seats 11,12 extend at right angles to the direction of movement of the valve member 3. It can be easily understood from the figure that the diameter of the seat 11 is larger than the diameter of the seat 12. Seat 12 is made sufficiently wide to allow radial expansion of an O-ring 13 attached to valve member 3 forming part of an elastomeric seal.

The valve member 3 has a disc-shaped surface 14 which cooperates with the seat 11 to form a mechanical seal under the action of the compression spring 8. elastomer
- A button-shaped projection or O-ring retaining member 15 with a circumferential groove 16 into which a Q-+7 ring 13 forming a seal is inserted extends from said disc-shaped surface 14 to the annular insert 1.
It extends into 0.

In the rest position, the valve member 3 is held with its disc-shaped surface 14 against the seat 11 of the insert 10 under the action of a keel 8 . Before this abutting engagement, the O-ring 13 is already in contact with the seat 12 of the insert 10, so that when the disc-shaped surface 14 comes into contact with the seat 11, the O-II ring 13 is slightly Preferably, it is deformed.

A mechanical seal and an elastomeric seal are thus formed. The spacing between seats 11 and 12 is selected such that, when the valve is closed, the deformation of the O-ring does not exceed its elastic limit and therefore the elastomer seal does not deteriorate prematurely.

In the embodiment shown in FIG. 1, the valve member 3 is provided with a cross-hole 17 communicating with the valve outlet 6, but as long as the valve member cooperates with the two seats in the valve chamber, it is not possible to allow fluid to flow therethrough. If possible, other structures may be used. 1. From FIG. It can be seen that the angle (B) between and is 90°.

The cross section of the 0-ring is initially circular with radius R6 p)
At the end of the valve closing cycle, the cross section is 2 of a semicircle with radius R,
It consists of two end parts and a central rectangular part with a width of 2Y and a height of H.

Since the compression of the 0-ring in the X direction is Xl, the following formula holds true; Since it is designed to never be compressed, the cross-sectional area of the O-+7 ring is constant and therefore: πRo2=πR, ” + H-
2yl, i.e. πR02−π(ROXI)2+ 2
(RO-Xl) 2yl, that is, when expressed in general terms using X and y, πRo2-+r(R1-x)2+4(R6-x)y
”' ”’ ”’ ”’ ”’ 17th, 4(A)
RO-x)y=πR♂-π(Rox)2, that is, Totoru.

Equation (B) shows that the radius varies from the initial value Ro to the final value R7.
This is the equation of the y-coordinate of the continuous radius center when changing to .

As can be seen from FIG. 2, the button-shaped protrusion 15 is
8, first taper part 19, curved band 20° second taper part 21
And it transforms and the 90-ring enters! f, large base 22
has. The cone angle of the first tapered portion 19 is (90°−2r
o) (see an1 on the right side of FIG. 2), and the conical angle of the second tapered portion 21 can be expressed as (90°-2γE) (see the left side of FIG. 2).

The curved zone 20 is a smooth transition between the tapered parts 19 and 21, and the increase in angle γ where the slope of the curved zone becomes large can be found from the following formula: 1l-Cotγ-dy/dx...・・・・・・・・・
(C) This is because the button-shaped protrusion is in contact with the O-ring at the point where the inclination becomes large (see Fig. 3).

Combining equations (B) and (C), we obtain the following relation:
This is an equation regarding the shape of the curved band 20.

When X-16, that is, the O-ring is not deformed, the following formula holds: Co t 7o-4+ 21o = 65" This means that the slope r0 of the tapered portion 19 is independent of the O-IJ song size. Therefore, the cone angle of the tapered portion is 25 pa or less.

Angle 2γ! depends on the size of the O-ring, but the second
As you can see from the table, the width of the numerical value is 0.177 in the radius of the cross section.
8x (0,070 inch) to 06985cR (0,2
Not large for a commonly available range of 0-rings (75 inches). In the table, -12= and R6-xl is the radius of the cross section of the O-ring when it is compressed to the maximum, and γ! is obtained from the above equation.

In commercially implementing the invention in this manner, the manufacturer uses conventional tools to form the outer conical surface 19 and an inner surface sized to the curvature 20 and the O-ring. All that is required is a tool to form the conical surface 21.

The life of the O-ring can be extended by pre-stressing the O-1 ring to prevent it from being damaged by the valve seat. FIG. 4 shows the Q-ring in its unforced and compressed states. In the figure, D is the diameter between the centers of the 0-11 rings at which force is applied. d is the diameter of the cross section of the O-1j ring.

A is the width of the compressed 0-ring. H is the height of the compressed Q-ring. I is the deviation of the center of the cross section between the state in which no force is applied and the state in which it is compressed.

To avoid damage, the stretch in the outer fiber should be
The compression in the 11 fibers must be equal and opposite. Stretching and compression are related to the initial length change, and the following equation is derived from FIG. 4: δ+A-d D+d δA4d-d As a result, no damage occurs in the following cases.

That is, (D-d)(δ+A-d)=(n+d)(-δ+
A-d) That is, δD+AD-dD-dδ+dA-1-d
"=-δD+AD-dD-dδ+Ad-d" That is, 2δD= 2Ad-2d2 That is, δD -a(A-d) That is, δ=8(A-d)
E) With respect to Figure 2, the center-to-center diameter is stretched by the preload dimension δ determined from equation (E) for each particular 0-ring when the 0-ring is placed on the button-like projection. Damage can be avoided if the button-like protrusions are sized to allow for damage.

Poppet and check valves constructed in accordance with the present invention have been tested and proven to be very reliable and capable of being used repeatedly at high speed cycles without failure.

The above description is only related to one preferred embodiment of the present invention, and it goes without saying that the present invention may be modified as appropriate as long as it does not depart from the spirit and scope of the present invention.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a poppet valve according to one embodiment of the present invention. FIG. 2 is an enlarged view of the O-ring and O-ring retaining member. FIG. 3 is a diagrammatic view of the main parts of the O-ring in two positions engaging the Q-IJ ring retention member. Figure 4 shows the O-ring with no force applied and the compressed O-ring.
-1,1 is a sectional view of the ring. 1... Valve box, 2... Valve chamber, 6.
... Valve member, 11.12° - Seat, 1
3...0-ring, 14...disk-shaped surface, 15°°°°° button-shaped projection (0-ring holding member), 19...first taper Department,
20... Curved band, 21... Second tapered portion = 16- Fig. 1

Claims (1)

[Claims] 1 (+) valve chamber, (11) annular valve seat, (II+) movable within the valve chamber, having a 0 to ring holding chamber, towards the annular valve seat; a valve member having an O-ring retaining member projecting toward the valve; the resulting O-ring, the O-ring retaining member having (v) a head portion remote from the valve member, (vl) a groove between the head portion and the valve member, the groove having: , (a) a first conical portion extending inward from the head portion and having a cone angle of approximately 25° or less; (b) at least approximately (90°−2rf) (herein) separated from the first conical portion inwardly; where γ is the radius of the cross-section of the 0-ring when the valve is open!D%Xl is the reduced length of the radius of the cross-section of the Q-ring when the valve is closed. (c) the increasing value of the cone angle (90° - 2γ, ) of the curved band is given by the formula: (where Ro is as above) In the same sense, x is the reduced length of the cross-sectional radius of the O-ring at the conical part where the slope of the curved zone increases. The curved band forms a smooth transition area, and as a result, the O-ring retaining member does not get in the way of the O-ring even if the O-ring is deformed when the valve is closed.
In other words, when there is a poppet that is characterized by not compressing the O-ring, the length δ obtained by the following formula is
Poppet valve or check valve according to claim 1, characterized in that the diameter of the center is subtracted from the center of the O-II ring by: C-(A-d) (where d is the applied force) D is the diameter of the cross-section of the long O-ring, D is the diameter between the centers of the O-ring with no force applied, and A is the compressed Q-IJ song width). 3. The valve member and the valve seat form a mechanical seal of an annular profile therebetween, the diameter of the ring being larger than the diameter of the sealing ring made of elastic material. Poppet valve or check valve.